Frequently Asked Questions
General
Vaccines
Q: Worldwide, what is the most common cancer that kills women?
A: According to WHO statistics, the most common type of cancer that kills women worldwide is breast cancer.
The five most common cancers that kill women are, in order of frequency, breast cancer, lung cancer, stomach cancer, colorectal cancer, and cervical cancer. In some developing countries cervical cancer is the most common cancer found in women.
-Courtesy Of MedicineNet.com, A Very Informative Website
Q: What are the warning signals of cancer?
A: A sore or ulcer that does not heal within 3 weeks with antibiotics especially in mouth. Pearly white patches in the mouth.
Inability to hold salty food in mouth.
Unusual bleeding or discharge from any orifice.
Thickening or lump in breast or elsewhere in the body.
Repeated abdominal cramps, indigestion. Difficulty in swallowing which lasts more than 3 weeks. Changes in bowel habits [Diarrhoea & Consumption] lasting for more than 3 weeks.
Hoarseness of voice, nagging cough; persisting even after treatment for 3 weeks.
Difficulty in urination, blood in urine, especially if you are above 45 years of age.
Change in wart or mole.
Listlessness, anaemia, intermittent fever which are not controlled by conversational medication.
Impairment in vision, white patches the eye, often shining at night.
These signs need not always be due to Cancer. But consult a specialist doctor if you have any of the above symptoms
-Courtesy Of Regional Cancer Centre, A Very Informative Website
Q: What are the side effects of radiation and chemotherapy?
A: First it has to be understood that all the side effects are temporary and will vanish in course of time. Depending on the site of radiation treatment, the symptoms will vary. Diarrhea, dryness of mouth, mouth soreness, difficulty in swallowing, loss of appetite and taste and abdominal cramps are some of the side effects due to radiation.
Chemotherapeutic drugs also can cause severe discomfort. Loss of hair, nausea, vomiting, diarrhea, and anaemia are some of the severe complaints. As in the case of sickness caused by radiotherapy, the sickness caused by chemotherapy also vanishes 2 to 3 weeks after completion of treatment.
-Courtesy Of Regional Cancer Centre, A Very Informative Website
Q: What is the best method by which cancer is treated?
A: The best treatment method for cancer depends on several factors, of which the most important are the site of cancer, type of cancer, spread of the disease when diagnosed, general health of the patient etc.
Some cancers are best removed by operation and are cured by this method. For some other types the best treatment is radiation: given externally, [Teletherapy] which is administered with Cobalt or Linear accelerator units or by inserting radioactive needles [radium, caesium. Cobalt etc.] into the body [Brachy therapy] or by combining both external and brachy therapy methods. Certain cancers are treated by drugs [chemotherapy] only.
Very often some cancers need all the three methods of treatment. The treating doctor choses the best method considering several of the above factors. In some cases surgery will remove a portion of the tumor, then treatment is continued by radiation. Radiation is given also to shrink the tumor so that a removal of the tumor by surgery can be done later.
-Courtesy Of Regional Cancer Centre, A Very Informative Website
Q: Is radiation a cause for cancer?
A: Radiation is widely used to diagnose many diseases. Radiation is also a very successful method to treat cancer. These are absolutely proper and safe uses. However Radiation is extremely dangerous and can cause cancer when not properly handled. Over exposure to X-rays, or byproducts of atomic radiation can contribute to the development of cancer especially Leukemia.
-Courtesy Of Regional Cancer Centre, A Very Informative Website
Q: Do viruses cause cancer?
A: There is good evidence to suspect that viruses may cause cancer in humans – Leukemia, nasopharyngeal cancer, liver and cervix cancer are considered now as being caused by viruses.
-Courtesy Of Regional Cancer Centre, A Very Informative Website
Q: Is cancer hereditary?
A: Certain cancers are seen to occur in families. This does not mean that the disease has been transmitted from parent to children through genetic material. The same life style usually run in families and this could as well be the reason.Scientists believe that if there is a hereditary component, its effect is indeed very little.
-Courtesy Of Regional Cancer Centre, A Very Informative Website
Q: What is cancer?
A: Cancer is a common name for a group of diseases characterized by uncontrolled proliferation of abnormal cells. Cell division is the mainstay of human life. Human body is made up of several organs like brain, lung, liver, stomach etc. and each organ is made up of cells. Organs and tissues are constituted by cells characteristic of that organ. Cells divide for growth of an organ, for repairing tissue damage and to maintain functions of the organ.
The divided cells are the exact replica of the parent cell. Sometimes due to some faulty mechanism or due to factors which are unknown yet, the divided cells are abnormal i.e., their structure is not the same as that of its parent cells. They cannot discharge the functions like the normal cells but requires the same food as the normal cells. These cells start dividing and a large number of abnormal cells are produced. As a result of the proliferation of abnormal cells the body organs do not function normally and the persons nutrition is impaired rapidly.
These cells cluster to form lumps, swellings, and sometimes produce ulcers in the respective organs. However in the case of blood cancer — Leukemia – the abnormal cells start circulating throughout the blood streams so, no visible lump or swellings are observed. (Cancer is known by its different types like sarcoma, lymphoma, Leukemia, myeloma, carcinoma etc.). The most important characteristic of cancer is that the cancer cells breakaway from the tissue or organ of origin and starts spreading to other parts of the body through lymphatic channels or cavities or blood vessels.
They then deposit themselves in other parts of the body where it grows again. This is known as the metastasis. Because of this unique characteristic it becomes difficult to cure or to control cancer when it has spread.
-Courtesy Of Regional Cancer Centre, A Very Informative Website
Q: What is ductal carcinoma in situ (DCIS)?
A: Ductal carcinoma in situ (DCIS) is a pre-invasive form of breast cancer—often considered stage zero—that hasn’t spread beyond the breast. A recent study in the Journal of American Medical Association Internal Medicine found that when DCIS was described using the word cancer, women were more likely to choose more invasive surgical treatments. However, another recent paper in the Journal of American Medical Association calls for a narrowing of the definition of cancer, which may affect how DCIS is diagnosed and treated in the future.
-Courtesy Of Women’s Health, A Very Informative Website
Q: What does breast density have to do with breast cancer?
A: Breast density has to do with the tissue in your breasts and how that shows up on a mammogram. But while you can’t feel this out on your own, you might find out about it at your next screening: Many states have adopted breast density notification laws, which require physicians to inform a patient if they have dense breasts, according to a new report in the journal Radiology.
So why should you care about how dense your set is? There are two main reasons, says Debra Ikeda, M.D., professor of radiology at Stanford School of Medicine. “There’s an association between dense breast tissue and a slightly higher risk of having breast cancer,” says Ikeda. It’s worth noting, though, that this association is much smaller than any genetic risk factor. “The second problem is that of masking,” says Ikeda. This is what happens when dense breast tissue shows up as white on a mammogram, making it harder to spot cancer (which also shows up white). However, studies have shown that this is less of an issue in digital mammograms as opposed to film screen mammograms.
But don’t freak out if you see this new language on your mammography report. While researchers seem pretty divided on the issue, having dense breast tissue doesn’t necessarily mean you need additional tests—especially since roughly half of all women have dense breasts. It’s simply something to keep in mind and to discuss with your doctor—along with any other risk factors you may have, says Ikeda. -Courtesy Of Women’s Health, A Very Informative Website
Q: Do most women die of breast cancer?
A: Women fear breast cancer more than any other disease. And many people believe that most women die of breast cancer. But that’s not the case. In the U.S., breast cancer is the fifth-leading cause of death for women. Heart disease is first.
Five leading causes of death for American women in 2004:
Heart Disease-27.2 percent (of all deaths)
Cancer-22 percent
Stroke-7.5 percent
Chronic Lower Respiratory Disease-5.2 percent
Alzheimer’s Disease-3.9 percent
The American Cancer Society estimates that in 2010, 207,000 women will be diagnosed with invasive breast cancer and that 40,000 will die of the disease.
-Courtesy Of Women’s Health, A Very Informative Website
Q: Is it true that 1 in 8 women will get breast cancer?
A: Not exactly. The one-in-eight statistic doesn’t accurately reflect the average woman’s breast cancer risk. Age is the most important risk factor for breast cancer. That means the older a woman is, the greater her risk of developing the disease. Statistics from the U.S. National Cancer Institute show that a woman’s chance of being diagnosed with breast cancer by age is:
From age 20 to age 30 . . . 1 in 2,000
From age 30 to age 39 . . . 1 in 229
From age 40 to age 49 . . . 1 in 68
From age 50 to age 59 . . . 1 in 37
From age 60 to age 69 . . . 1 in 26
Ever . . . . . . . . . . . . . . . . . . . .1 in 8
“Ever” is lifetime risk. This means a woman has a one-in-eight chance of getting breast cancer after the age of 70.
-Courtesy Of Women’s Health, A Very Informative Website
Q: How long until considered "cancer free"?
A: According to the National Cancer Institute, the five-year survival rate for non-metastatic breast cancer (breast cancer that has not spread beyond the breast) is 80%. Newspapers and television usually translate that to, “If you’ve survived for five years, you’re cancer-free.”
This is a bit misleading. It’s true that during the first five years, the risk of recurrence is highest. But breast cancer can recur even after five years. The important point to know is that the more time passes, the lower the risk of recurrence becomes.
The chance of surviving breast cancer depends on MANY different factors taken together. Lymph node involvement has a strong influence on prognosis. The more lymph nodes involved, the more serious the cancer. Some of the other factors that affect outcome are your general health, the size of the cancer, hormone receptor status, growth rate, tumor grade, and HER2/neu status.
Even with the best information, no one can predict the future. Each of us is unique, and how each woman’s body and mind handle breast cancer and treatment is truly a mystery. Many women have beat the odds, while other women “sure to do well” somehow didn’t. You just have to do the best you can, with the best team of doctors and nurses that you can assemble, together with your support network. Then focus on the power of your mind, and you can experience the momentum you need to move through treatment and beyond.
The good news is that more and more women are living longer than five years past breast cancer as a result of early detection, more effective breast cancer therapy, and better overall medical care.
-Courtesy Of Breastcancer.org, A Very Informative Website
Q: What can you tell me about sentinel node biopsy?
A: Sentinel node biopsy, also known as sentinel lymph node dissection, is an alternative to axillary lymph node dissection.
Lymph nodes are filters that trap cancer cells (and other unwanted cells) and eliminate them from the body. Pathologists check lymph nodes for cancer cells that have left the tumor and are trying to spread.
The presence (“node-positive”) or absence (“node-negative”) of cancer in the lymph nodes is one of the most important factors your doctor will consider when determining how aggressive your treatment needs to be. Read more about what lymph node involvement means.
In both types of lymph node dissection, lymph nodes are removed from the underarm area next to the breast. A pathologist checks to see if they have cancer cells in them. In sentinel node biopsy, fewer lymph nodes are removed.
Doctors once thought that removing as many lymph nodes as possible would reduce the risk of cancer ever spreading. Doctors also wanted to remove as many lymph nodes as possible to get a better idea of how many lymph nodes were affected by cancer. Sentinel node biopsy has changed the way doctors think about this issue.
In sentinel node dissection, the surgeon looks for the sentinel node or nodes, which is the first lymph node or first few nodes that filter fluid draining away from the breast. If cancer cells are traveling in the lymph system, the sentinel node is more likely than the others to contain them. So, rather than remove 10 or more nodes, surgeons remove only the one node, or a cluster of two or three, which is most likely to have cancer. If the sentinel node is clean, chances are the other nodes are clean, too.
But it’s important to remember that sentinel node biopsy is not appropriate for everyone. In 2014, the American Society of Clinical Oncology released guidelines on sentinel lymph node biopsy.
The guidelines say sentinel lymph node biopsy SHOULD be offered under these circumstances:
Breast cancer in which there is more than one tumor, all of which have formed separately from one another (doctors call these multicentric tumors); these types of breast cancers are rare
DCIS treated with mastectomy
Women who have previously had breast cancer surgery or axillary lymph node surgery
Women who have been treated before with chemotherapy or another systemic treatment (treatment before surgery is called neoadjuvant treatment)
Sentinel node biopsy SHOULD NOT be offered under these circumstances:
The cancer is 5 cm or larger or locally advanced (the cancer has spread extensively in the breast or to the nearby lymph nodes)
The cancer is inflammatory breast cancer
DCIS treated with lumpectomy
The woman is pregnant
The guidelines also say:
Women with negative sentinel node biopsies shouldn’t have axillary node surgery.
Women with one or two positive sentinel nodes who plan to have lumpectomy plus radiation also don’t need axillary node surgery.
Women who have one or more positive sentinel nodes and plan to have mastectomy with no radiation should be offered axillary node surgery.
-Courtesy Of Breastcancer.org, A Very Informative Website
Q: What are margins in relation to breast cancer?
A: Margins, also known as “margins of resection,” refer to the distance between a tumor and the edge of the surrounding tissue that’s removed along with it.
When a tumor is removed, some tissue surrounding it is also removed. The tumor with surrounding tissue is rolled in a special ink so that the outer edges, or margins, are clearly visible under a microscope. A pathologist checks the tissue under a microscope to see if the margins are free of cancer cells.
Depending upon what the pathologist sees, the margins of a tumor are described as:
Positive margins: Cancer cells extend out to the edge of the tissue, where the ink is.
Negative margins: No cancer cells are found in the ink.
Close margins: Any situation that falls between positive and negative is considered “close.”
Knowing how close cancer cells are to the edge of the removed tissue helps in making the right treatment decisions. This is especially important in deciding whether additional surgery is needed. If the margins are positive, more surgery is needed. If the margins are close, you may or may not need more surgery. If the margins are negative, you probably don’t need more surgery.
The definition of “negative margins” varies from one hospital to another. You may want to ask your doctor whether your margins were positive, negative, or close, and how “negative” is defined by your medical team.
To help standardize this definition, the American Society for Radiation Oncology and the Society of Surgical Oncology issued new guidelines in February 2014 saying that clear margins, no matter how small as long as there was no ink on the cancer tumor, should be the standard for lumpectomy surgery.
-Courtesy Of Breastcancer.org, A Very Informative Website
Q: Risks for Herceptin Therapy?
A: Herceptin (chemical name: trastuzumab) is a medicine that is currently given to women with advanced breast cancer who have an overactive HER2/neu gene, found in about 25% of breast cancers. In clinical trials, Herceptin is also offered to women with positive lymph nodes and an abnormal HER2/neu gene.
Herceptin is considered an immune therapy because it imitates the way the body’s own immune system fights cancer. It works like an antibody, a specialized protein that targets the misbehaving HER2/neu gene.
Early clinical trials found that some women had congestive heart failure after they took Herceptin together with a type of chemotherapy called Adriamycin (chemical name: doxorubicin). In congestive heart failure, the heart muscle weakens and is less able to effectively pump blood throughout the body. When Herceptin is given without Adriamycin, heart failure is rare, mild, and usually treated successfully. Herceptin is commonly given with other types of chemotherapy, without an added significant risk of heart problems. In addition, many women take Herceptin alone with a very low risk to the heart.
Bear in mind that breast cancer with abnormal HER2/neu genes tends to be aggressive. So, for women in this situation, the benefits of Herceptin may far outweigh the risks.
-Courtesy Of Breastcancer.org, A Very Informative Website
Q: Can benign cysts become cancerous?
A: Cysts are very common and rarely turn into cancers. But it’s extremely important to find out whether what you have is just a cyst or something else.
If you feel a lump in your breast and you don’t know what it is, have your doctor check it. Some women get what are called cyclical lumps—cysts that appear sometime before the start of the menstrual cycle, and later shrink or disappear. These are generally harmless. But, again, if you have them, you should be monitored by a doctor with breast expertise.
Even if you’ve had cysts in the past, if you find a new lump in your breast, don’t assume it’s a cyst. If the lump doesn’t go away or gets larger, it’s important to check it out further.
Ultrasound is the easiest way to see if a lump is a cyst or not. Your doctor may insert a needle into a lump to see if it’s a cyst. In a simple cyst, the needle will drain off the fluid. A pathologist will check the fluid to make sure there are no cancer cells in it. If the lump is made up of breast cells, a tissue sample can be taken out with the needle and checked by a pathologist under the microscope.
In some women, the examination under the microscope may reveal epithelial hyperplasia, which is just a harmless overgrowth of normal breast cells. Another finding, atypical hyperplasia, is an increase in breast cells that have started to look different from normal cells. The atypical form is associated with a slightly increased risk of developing breast cancer later on.
Routine mammograms are important for all women, regardless of your history of cysts or other biopsy results.
-Courtesy Of Breastcancer.org, A Very Informative Website
Q: Worried about lump in breast?
A: Eight out of 10 lumps that women may feel in their breasts are benign (not cancerous). A benign lump can be a collection of normal or hyperactive breast gland cells, or it may be a water-filled sac (cyst).
In any event, if you feel a lump and you’re worried about it, DON’T HESITATE TO SEE A DOCTOR. By getting a doctor to check the lump you’ll ease your fears. And if it’s something serious, you can start getting treatment right away.
One way to make lumps less frightening is to get to know what your breasts normally feel like. There’s no better way to find out than by doing your monthly breast self-exam. The upper, outer area—near your armpit—tends to have the most prominent lumps and bumps. The lower half of your breast can feel like a sandy or pebbly beach. The area under the nipple can feel like a collection of large grains. Another part might feel like a lumpy bowl of oatmeal.
If you notice any changes in your breasts that last over a full month’s cycle or that seem to get worse or more obvious over time, tell your doctor. Knowing how your breasts usually look and feel may also help you avoid needless biopsies.
If you’re worried about getting breast cancer, read about breast cancer risk factors to find out what your risk is.
-Courtesy Of Breastcancer.org, A Very Informative Website
Q: What are the signs of breast cancer?
A: Often there are no outward signs of breast cancer that you can see or feel. If there are outward signs, the more common ones include a lump, an area of thickening, or a dimple in the breast. Less common signs include breast swelling and redness or an enlarged underarm lymph node.
But even if you have one or more of these signs, it still doesn’t mean you have breast cancer. Remember that most breast lumps turn out to be benign (not cancerous).
Still, it’s extremely important that you SEE YOUR DOCTOR RIGHT AWAY if you’re worried that you might have breast cancer. Having your doctor take a look will ease your worry, and if anything is found, you’ll be able to take care of it quickly.
Physical examination of the breast is one way to find breast cancer. You can read about other screening methods for detecting breast cancer in our Screening & Testing section.
-Courtesy Of Breastcancer.org, A Very Informative Website
Q: How often should I do a breast self exam (BSE)?
A: Give yourself a breast self-exam once a month. Look for any changes in breast tissue, such as changes in size, feeling a palpable lump, dimpling or puckering of the breast, inversion of the nipple, redness or scaliness of the breast skin, redness or scaliness of the nipple/areola area, or discharge of secretions from the nipple.
If you discover a persistent lump in your breast or any changes, it is very important that you see a physician immediately. Though 8 out of 10 lumps are benign, all require evaluation to confirm that they are not cancerous.
Women should perform their breast self exam 7-10 days after their menstrual period starts which is also when their breasts are the least tender and lumpy. If they are no longer menstruating, then she should select the same day of the month (first of the month for example) and mark it on the calendar to remind herself when to perform this self exam. What to look for is a change from last month’s exam to this month’s exam. It is not unusual to have lumpy or bumpy breasts.
All women should know the geography of their own breasts. If having trouble remembering, draw a diagram of where the lumps, bumps, grooves, and other findings are felt so that this can be used as a reminder from month to month. There is no added value in doing breast self exams more often than monthly. Also the findings may be different as well, in relationship to where a woman is in her menstrual cycle. -Courtesy Of National Breast Cancer Foundation,Inc – A Very Informative Website
Q: Is there a link between oral contraceptives and breast cancer?
A: There is an increased risk of breast cancer for women who have been using birth control pills for more than five years. However due to the low amount of hormones in birth control pills today, the risk is relatively small. But if a young woman has a significant family history of breast cancer, her gynecologist may recommend taking a break for a year from the pill at the 5-year time frame then resuming again for another 5 years. Although evidence-based research data does not offer strong support for this standard of care, it has nevertheless become an increasingly common practice. -Courtesy Of National Breast Cancer Foundation,Inc – A Very Informative Website
Q: Can cancer treatment vaccines be combined with other types of cancer therapy?
A: Yes. In many of the clinical trials of cancer treatment vaccines that are now under way, vaccines are being given with other forms of cancer therapy. Therapies that have been combined with cancer treatment vaccines include surgery, chemotherapy, radiation therapy, and some forms of targeted therapy, including therapies that are intended to boost immune system responses against cancer.
Several studies have suggested that cancer treatment vaccines may be most effective when given in combination with other forms of cancer therapy . In addition, in some clinical trials, cancer treatment vaccines have appeared to increase the effectiveness of other cancer therapies .
Additional evidence suggests that surgical removal of large tumors may enhance the effectiveness of cancer treatment vaccines. In patients with extensive disease, the immune system may be overwhelmed by the cancer. Surgical removal of the tumor may make it easier for the body to develop an effective immune response.
Researchers are also designing clinical trials to answer questions such as whether a specific cancer treatment vaccine works best when it is administered before chemotherapy, after chemotherapy, or at the same time as chemotherapy. Answers to such questions may not only provide information about how best to use a specific cancer treatment vaccine but also reveal additional basic principles to guide the future development of combination therapies involving vaccines.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: Do cancer vaccines have side effects?
A: Vaccines intended to prevent or treat cancer appear to have safety profiles comparable to those of traditional vaccines . However, the side effects of cancer vaccines can vary among vaccine formulations and from one person to another.
The most commonly reported side effect of cancer vaccines is inflammation at the site of injection, including redness, pain, swelling, warming of the skin, itchiness, and occasionally a rash.
People sometimes experience flu-like symptoms after receiving a cancer vaccine, including fever, chills, weakness, dizziness, nausea or vomiting, muscle ache, fatigue, headache, and occasional breathing difficulties. Blood pressure may also be affected.
Other, more serious health problems have been reported in smaller numbers of people after receiving a cancer vaccine. These problems may or may not have been caused by the vaccine. The reported problems have included asthma, appendicitis, pelvic inflammatory disease, and certain autoimmune diseases, including arthritis and systemic lupus erythematosus.
Vaccines, like any other medication affecting the immune system, can cause adverse effects that may prove life threatening. For example, severe hypersensitivity (allergic) reactions to specific vaccine ingredients have occurred following vaccination. However, such severe reactions are quite rare.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: Can researchers add ingredients to cancer vaccines to make them work better?
A: Antigens and other substances are often not strong enough inducers of the immune response to make effective cancer treatment vaccines. Researchers often add extra ingredients, known as adjuvants, to treatment vaccines. These substances serve to boost immune responses that have been set in motion by exposure to antigens or other means. Patients undergoing experimental treatment with a cancer vaccine sometimes receive adjuvants separately from the vaccine itself .
Adjuvants used for cancer vaccines come from many different sources. Some microbes, such as the bacterium Bacillus Calmette-Guérin (BCG) originally used as a vaccine against tuberculosis, can serve as adjuvants. Substances produced by bacteria, such as Detox B, are also frequently used. Biological products derived from nonmicrobial organisms can be used as adjuvants, too. One example is keyhole limpet hemocyanin (KLH), which is a large protein produced by a sea animal. Attaching antigens to KLH has been shown to increase their ability to stimulate immune responses. Even some nonbiological substances, such as an emulsified oil known as montanide ISA–51, can be used as adjuvants.
Natural or synthetic cytokines can also be used as adjuvants. Cytokines are substances that are naturally produced by white blood cells to regulate and fine-tune immune responses. Some cytokines increase the activity of B cells and killer T cells, whereas other cytokines suppress the activities of these cells. Cytokines frequently used in cancer treatment vaccines or given together with them include interleukin 2 (IL2, also known as aldesleukin), interferon alpha (INF–a), and GM–CSF, also known as sargramostim.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: What types of vaccines are being studied in clinical trials?
A: Vaccines to prevent HPV infection and to treat several types of cancer are being studied in clinical trials.
The list below shows the types of cancer that are being targeted in active cancer prevention or treatment clinical trials using vaccines. If you are accessing this fact sheet online, the cancer names are links to search results from NCI’s clinical trials database.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: Has the FDA approved any cancer treatment vaccines?
A: In April 2010, the FDA approved the first cancer treatment vaccine. This vaccine, sipuleucel-T (Provenge®, manufactured by Dendreon), is approved for use in some men with metastatic prostate cancer. It is designed to stimulate an immune response to prostatic acid phosphatase (PAP), an antigen that is found on most prostate cancer cells. In a clinical trial, sipuleucel-T increased the survival of men with a certain type of metastatic prostate cancer by about 4 months (19).
Unlike some other cancer treatment vaccines under development, sipuleucel-T is customized to each patient. The vaccine is created by isolating immune system cells called antigen-presenting cells (APCs) from a patient’s blood through a procedure called leukapheresis. The APCs are sent to Dendreon, where they are cultured with a protein called PAP-GM-CSF. This protein consists of PAP linked to another protein called granulocyte-macrophage colony-stimulating factor (GM-CSF). The latter protein stimulates the immune system and enhances antigen presentation.
APC cells cultured with PAP-GM-CSF constitute the active component of sipuleucel-T. Each patient’s cells are returned to the patient’s treating physician and infused into the patient. Patients receive three treatments, usually 2 weeks apart, with each round of treatment requiring the same manufacturing process. Although the precise mechanism of action of sipuleucel-T is not known, it appears that the APCs that have taken up PAP-GM-CSF stimulate T cells of the immune system to kill tumor cells that express PAP.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: How are cancer treatment vaccines designed to work?
A: Cancer treatment vaccines are designed to treat cancers that have already developed. They are intended to delay or stop cancer cell growth; to cause tumor shrinkage; to prevent cancer from coming back; or to eliminate cancer cells that have not been killed by other forms of treatment.
Developing effective cancer treatment vaccines requires a detailed understanding of how immune system cells and cancer cells interact. The immune system often does not “see” cancer cells as dangerous or foreign, as it generally does with microbes. Therefore, the immune system does not mount a strong attack against the cancer cells.
Several factors may make it difficult for the immune system to target growing cancers for destruction. Most important, cancer cells carry normal self antigens in addition to specific cancer-associated antigens. Furthermore, cancer cells sometimes undergo genetic changes that may lead to the loss of cancer-associated antigens. Finally, cancer cells can produce chemical messages that suppress anticancer immune responses by killer T cells. As a result, even when the immune system recognizes a growing cancer as a threat, the cancer may still escape a strong attack by the immune system .
Producing effective treatment vaccines has proven much more difficult and challenging than developing cancer preventive vaccines . To be effective, cancer treatment vaccines must achieve two goals. First, like traditional vaccines and cancer preventive vaccines, cancer treatment vaccines must stimulate specific immune responses against the correct target. Second, the immune responses must be powerful enough to overcome the barriers that cancer cells use to protect themselves from attack by B cells and killer T cells. Recent advances in understanding how cancer cells escape recognition and attack by the immune system are now giving researchers the knowledge required to design cancer treatment vaccines that can accomplish both goals.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: What cancer preventative vaccines are approved in the United States?
A: The U.S. Food and Drug Administration (FDA) has approved two vaccines, Gardasil® and Cervarix®, that protect against infection by the two types of HPV—types 16 and 18—that cause approximately 70 percent of all cases of cervical cancer worldwide. At least 17 other types of HPV are responsible for the remaining 30 percent of cervical cancer cases . HPV types 16 and/or 18 also cause some vaginal, vulvar, anal, penile, and oropharyngeal cancers.
In addition, Gardasil protects against infection by two additional HPV types, 6 and 11, which are responsible for about 90 percent of all cases of genital warts in males and females but do not cause cervical cancer.
Gardasil, manufactured by Merck & Company, is based on HPV antigens that are proteins. These proteins are used in the laboratory to make four different types of “virus-like particles,” or VLPs, that correspond to HPV types 6, 11, 16, and 18. The four types of VLPs are then combined to make the vaccine. Because Gardasil targets four HPV types, it is called a quadrivalent vaccine. In contrast with traditional vaccines, which are often composed of weakened whole microbes, VLPs are not infectious. However, the VLPs in Gardasil are still able to stimulate the production of antibodies against HPV types 6, 11, 16, and 18.
Cervarix, manufactured by GlaxoSmithKline, is a bivalent vaccine. It is composed of VLPs made with proteins from HPV types 16 and 18. In addition, there is some initial evidence that Cervarix provides partial protection against a few additional HPV types that can cause cancer. However, more studies will be needed to understand the magnitude and impact of this effect.
Gardasil is approved for use in females to prevent cervical cancer and some vulvar and vaginal cancers caused by HPV types 16 and 18, and for use in males and females to prevent anal cancer and precancerous anal lesions caused by these HPV types. Gardasil is also approved for use in males and females to prevent genital warts caused by HPV types 6 and 11. The vaccine is approved for these uses in females and males ages 9 to 26. Cervarix is approved for use in females ages 9 to 25 to prevent cervical cancer caused by HPV types 16 and 18.
The FDA has also approved a cancer preventive vaccine that protects against HBV infection. Chronic HBV infection can lead to liver cancer. The original HBV vaccine was approved in 1981, making it the first cancer preventive vaccine to be successfully developed and marketed. Today, most children in the United States are vaccinated against HBV shortly after birth.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: How do cancer preventative vaccines work?
A: Cancer preventive vaccines target infectious agents that cause or contribute to the development of cancer . They are similar to traditional vaccines, which help prevent infectious diseases, such as measles or polio, by protecting the body against infection. Both cancer preventive vaccines and traditional vaccines are based on antigens that are carried by infectious agents and that are relatively easy for the immune system to recognize as foreign.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: What are cancer vaccines?
A: Cancer vaccines are medicines that belong to a class of substances known as biological response modifiers. Biological response modifiers work by stimulating or restoring the immune system’s ability to fight infections and disease. There are two broad types of cancer vaccines:
Preventive (or prophylactic) vaccines, which are intended to prevent cancer from developing in healthy people; and
Treatment (or therapeutic) vaccines, which are intended to treat an existing cancer by strengthening the body’s natural defenses against the cancer.
Two types of cancer preventive vaccines are available in the United States, and one cancer treatment vaccine has recently become available.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: How do vaccines stimulate the immune system?
A: White blood cells, or leukocytes, play the main role in immune responses. These cells carry out the many tasks required to protect the body against disease-causing microbes and abnormal cells.
Some types of leukocytes patrol the circulation, seeking foreign invaders and diseased, damaged, or dead cells. These white blood cells provide a general—or nonspecific—level of immune protection.
Other types of leukocytes, known as lymphocytes, provide targeted protection against specific threats, whether from a specific microbe or a diseased or abnormal cell. The most important groups of lymphocytes responsible for carrying out immune responses against such threats are B cells and cytotoxic (cell-killing) T cells.
B cells make antibodies, which are large secreted proteins that bind to, inactivate, and help destroy foreign invaders or abnormal cells. Most preventive vaccines, including those aimed at hepatitis B virus (HBV) and human papillomavirus (HPV), stimulate the production of antibodies that bind to specific, targeted microbes and block their ability to cause infection. Cytotoxic T cells, which are also known as killer T cells, kill infected or abnormal cells by releasing toxic chemicals or by prompting the cells to self-destruct (a process known as apoptosis).
Other types of lymphocytes and leukocytes play supporting roles to ensure that B cells and killer T cells do their jobs effectively. These supporting cells include helper T cells and dendritic cells, which help activate killer T cells and enable them to recognize specific threats.
Cancer treatment vaccines are designed to work by activating B cells and killer T cells and directing them to recognize and act against specific types of cancer. They do this by introducing one or more molecules known as antigens into the body, usually by injection. An antigen is a substance that stimulates a specific immune response. An antigen can be a protein or another type of molecule found on the surface of or inside a cell.
Microbes are recognized by the immune system as a potential threat that should be destroyed because they carry foreign or “non-self” antigens. In contrast, normal cells in the body have antigens that identify them as “self.” Self antigens tell the immune system that normal cells are not a threat and should be ignored .
Cancer cells can carry both self antigens and cancer-associated antigens. The cancer-associated antigens mark the cancer cells as abnormal, or foreign, and can cause B cells and killer T cells to mount an attack against them.
Cancer cells may also make much larger amounts of certain self antigens than normal cells. Because of their high abundance, these self antigens may be viewed by the immune system as being foreign and, therefore, may trigger an immune response against the cancer cells.
-Courtesy Of National Cancer Institute, A Very Informative Website
Q: What are vaccines?
A: Vaccines are medicines that boost the immune system’s natural ability to protect the body against “foreign invaders,” mainly infectious agents, that may cause disease.
The immune system is a complex network of organs, tissues, and specialized cells that act collectively to defend the body. When an infectious microbe invades the body, the immune system recognizes it as foreign, destroys it, and “remembers” it to prevent another infection should the microbe invade the body again in the future. Vaccines take advantage of this response.
Traditional vaccines usually contain harmless versions of microbes—killed or weakened microbes, or parts of microbes—that do not cause disease but are able to stimulate animmune response against the microbes. When the immune system encounters these substances through vaccination, it responds to them, eliminates them from the body, and develops a memory of them. This vaccine-induced memory enables the immune system to act quickly to protect the body if it becomes infected by the same microbes in the future.
The immune system’s role in defending against disease-causing microbes has long been recognized. Scientists have also discovered that the immune system can protect the body against threats posed by certain damaged, diseased, or abnormal cells, including cancer cells.
-Courtesy Of National Cancer Institute, A Very Informative Website