Infections with certain viruses, bacteria, and parasites have been identified as strong risk factors for specific cancers. To examine the link between infections and cancer, researchers performed a systematic analysis of the proportion of cancer cases attributable to infection in 2008. They used data on cancer incidence from the GLOBOCAN project along with epidemiological data regarding the causal effects of infection on cancer. The data included information on 27 types of cancer from 182 countries.

They found that of the 12.7 million new cancer cases that occurred worldwide in 2008, 16 percent—or roughly two million—were attributable to infections. The rate of infection-related cancer was about three times higher in developing countries. For example, 3.3 percent of cancers in Australia and New Zealand were infection related, whereas 32.7 percent of cancers in sub-Saharan Africa were attributable to infections. The four main infections associated with cancer were human papillomavirus, hepatitis C, hepatitis B, and Helicobacter pylori. These infections were responsible for approximately 1.9 million cancer cases in 2008, mainly gastric, liver, and cervical cancers.

Cervical cancer accounted for about half of the infection-related cancers in women. Liver and gastric cancers accounted for more than 80 percent of the infection-related cancers in men.  About 30 percent of infection-related cancers occurred in people younger than 50 years. It’s important to note that it takes decades of chronic infection before an infection progresses to cancer.

Based on the statistics, the researchers noted that approximately two million cancer cases each year might be preventable with better public health methods for preventing infection. In an accompanying editorial, Dr. Goodarz Danaei, an assistant professor of global health at Harvard School of Public Medicine in Boston, noted that vaccines for HPV and hepatitis B are effective and that increasing their availability should be a priority for higher risk countries.[2] He suggests that increasing vaccine coverage could reduce the global burden of cancer.

References:

The thyroid is a gland in the throat that produces hormones mostly related to metabolic processes in the body. Overall, thyroid cancer is considered to be a highly curable cancer, with 97% of individuals alive at least five years following diagnosis. Standard treatment for well-differentiated thyroid cancer involves surgical removal of the thyroid. After surgery, some patients benefit from additional treatment with radioactive iodine. The iodine destroys any remaining cancer cells as well as the remaining healthy thyroid gland tissue.

Improvements in surgery mean that more of the thyroid gland is removed, which leaves fewer potential remaining cells to be treated with the iodine—meaning lower radiation doses are likely effective. This is important because higher doses of radiation carry added risks, including long-term complications such as secondary cancers. What’s more—patients treated with low-dose radiation can be treated as outpatients and experience fewer side effects.

The HiLo trial included 438 patients at 29 hospitals across the United Kingdom who were randomized to receive low-dose or high-dose radioiodine, each in combination with either thyrotropin alfa or thyroid hormone withdrawal before ablation.[1] The results indicated that patients who received a much lower dose of radioiodine taken in a single oral capsule had similar treatment success to those who had the high dose—but with a much lower rate of side effects. Success rates were 85.0% in the group receiving low-dose radioiodine versus 88.9% in the group receiving the high dose and 87.1% in the thyrotropin alfa group versus 86.7% in the group undergoing thyroid hormone withdrawal. The researchers concluded that the low-dose radioiodine was equally effective and that this will change the approach to treating thyroid cancer—making it more safe and reducing the risk of secondary cancers later in life.

Another randomized, phase 3 trial compared two thyrotropin-stimulation methods (thyroid hormone withdrawal and use of recombinant human thyrotropin) and two radioiodine (¹³¹I) doses in a 2-by-2 design.[2] The trial included 684 patients enrolled between 2007 and 2010. Success rates were similar between the two radiation doses and the two thyrotropin-stimulation methods, leading the researchers to conclude that the use of human thyrotropin and low-dose radioiodine may be sufficient for managing low-risk thyroid cancer.

The results of both these studies could change standard thyroid treatment—resulting in lower doses of radiation for most patients.

References:

How does cancer treatment affect fertility in men?

Chemotherapy: Chemotherapy can temporarily—and in some cases, permanently—stop sperm production by the testes.[1] The extent to which chemotherapy affects sperm production depends on several factors, including the type and dose of chemotherapy.

Radiation: Radiation to the abdomen or pelvis can also reduce or eliminate sperm production by the testes.

Surgery: Surgery that involves the removal of both testicles (an option for some men with prostate cancer) eliminates sperm production, but other types of surgery can also affect a man’s fertility. Some types of pelvic surgery, for example, can change or eliminate ejaculation.

Options for preserving fertility in men

Although many men are able to conceive naturally after cancer treatment, others are not.

If possible, men should talk with their doctor about their future fertility before beginning cancer treatment. Some options for preserving fertility require that steps be taken before cancer treatment begins.

Sperm banking is the most well-established method of preserving fertility in men.[2] It involves the collection and storage of sperm, ideally before cancer treatment begins. The samples are kept frozen at a lab or sperm bank until they are needed. Sperm can be stored in this way for many years. After being thawed, the sperm can be used for intrauterine insemination (IUI) or in vitro fertilization (IVF). During IUI, sperm are placed directly into a woman’s uterus. During IVF, mature eggs are removed from a woman’s ovary and mixed with the sperm in the lab. Embryos that result from IVF can then be placed in a woman’s uterus or frozen for later use.

If a sample contains very few viable sperm (or if a man has already undergone cancer treatment and has a low sperm count), another approach may be used to fertilize an egg. Intracytoplasmic sperm injection (ICSI) requires only a small number of healthy sperm, along with mature eggs that have been collected from a woman’s ovary. A single sperm is injected directly into each egg. The embryos that develop can then be placed in a woman’s uterus or frozen for later use.

If it is not possible to collect sperm from ejaculate, it may in some cases be possible to collect sperm directly from the testicles. This approach is still investigational.

Finally, it may also be possible to modify some cancer treatments to minimize their effects on subsequent fertility. During radiation therapy, for example, it may be possible to shield the testes in order to preserve sperm production.

Pregnancy after cancer

In the event that your fertility is not affected by cancer treatment (or recovers quickly or unexpectedly), you and your partner should use birth control if you do not wish to have a child. If you are trying to conceive a child naturally, your doctor may advise you to wait for several months after treatment; this allows for the elimination of sperm that may have been damaged during treatment.

In general, the risk of birth defects in children born to cancer survivors appears to be similar to the risk in the general population.[3] If your cancer was due to a hereditary cancer syndrome, such as Lynch syndrome (hereditary nonpolyposis colorectal cancer), your children may inherit the gene mutation responsible for your family’s increased risk of cancer. Talking with a genetic counselor may be helpful.

Other options for parenthood

Not all men have the luxury of being able to explore their reproductive options before beginning cancer treatment, and not all men will find a fertility preservation option that meets their needs. But there are still ways to become a parent. Discussion of other routes to parenthood may be a painful topic for men who want to father a child but cannot. But as cancer survivors consider how best to build their families, methods such as adoption are important options.

Adoption: Couples and individuals who wish to adopt have a range of options, including different types of domestic and international adoptions. You may wish to start by learning about the adoption laws in your state and by talking with other adoptive parents about the professionals and agencies they worked with. Before selecting an adoption agency, you may wish to talk with them about their attitudes toward placing a child with a cancer survivor. Many agencies will be receptive toward this, but it’s important to know before making a final decision.

Donor Sperm: Donor sperm is readily available from sperm banks and can be used for either intrauterine insemination or in vitro fertilization.

Individual decisions within a larger community

The decisions that you make about building a family (or about coming to terms with not building a family) will be intensely personal, but know that you are part of a larger community of patients and healthcare providers who are grappling with these issues.  To think about future parenthood is to think about life after cancer. For many people with cancer, planning for the future may provide the motivation needed to get through treatment.

More information?

Discuss with others…. http://cancerconnect.com/groups/young-adults/topics/fertility-after-cancer-treatment

Fertile Hope (www.fertilehope.org) provides a range of fertility resources for people with cancer.

References:

How does cancer treatment affect fertility in women?

Chemotherapy: Many chemotherapy drugs are toxic to the egg cells (oocytes) in the ovaries. If the number of remaining oocytes in the ovaries reaches a critically low point during treatment, women experience “acute ovarian failure.” This means that the ovaries stop functioning during or shortly after cancer treatment. If oocytes are lost during treatment but do not reach this critically low point, women are at risk for early menopause but may still be able to get pregnant for some time after treatment.

Radiation: Radiation to the pelvis can also destroy oocytes. Radiation to the pelvis can also affect uterine growth and blood flow, particularly if received before puberty.[1] A poorly developed uterus may make a woman more likely to have a miscarriage, or more likely to have a preterm or low-birthweight infant.

Surgery: Some cancers require surgical removal of the uterus, the ovaries, or both.

The effects of cancer treatment on fertility can vary substantially by age. Younger women, who have a larger pool of oocytes when they start cancer treatment, are more likely than older women to be able to get pregnant after treatment.[2]

Options for preserving fertility in women

If possible, women should talk with their doctor about their future fertility before beginning cancer treatment. Some options for preserving fertility require that steps be taken before cancer treatment begins.

One of the most established approaches for preserving fertility among female cancer patients is embryo freezing.[3] Before starting cancer treatment, a woman would be given hormones to stimulate the development of eggs in her ovaries. Mature eggs would be removed and fertilized with the sperm of her husband, partner or a sperm donor. The embryos that result from these fertilized eggs would be frozen for later use.

Although embryo freezing is an established approach to helping women become pregnant after cancer, there are downsides. A woman may not currently have a male partner and may be unwilling to use an anonymous sperm donor. It’s also important to be aware that embryo freezing takes approximately two weeks after the start of a woman’s period. If a woman needs to begin cancer treatment immediately, she may not be able to go through this process. Finally, this approach is only an option for women of childbearing age; stimulating the ovaries to produce mature eggs is not an option for girls who develop cancer during childhood.

Several other options are still in the experimental phase. One approach being explored is the freezing of unfertilized eggs.3 Once again, the ovaries would be stimulated to produce mature eggs before cancer treatment begins. The eggs would then be frozen without being fertilized by sperm. Currently, freezing unfertilized eggs is less likely to result in pregnancy than freezing embryos, largely because unfertilized eggs are less likely than embryos to survive the process of freezing and thawing. Nevertheless, it may be an option for women who do not have a male partner at the time of their cancer diagnosis, and it avoids the difficult issue of what to do with unused embryos.

Another promising but still experimental approach is to freeze all or a part of an ovary before cancer treatment.[4] After treatment, the ovarian tissue is implanted either back in the woman’s pelvis or in another location (such as under her skin). If this process is successful, the ovarian tissue will begin producing eggs. A safety concern with this approach is the possibility of reintroducing cancer cells along with the ovarian tissue, and the tissue will need to be carefully screened for cancer before it is transplanted.4

Finally, it may also be possible to modify some cancer treatments to minimize their effects on subsequent fertility. For example, shielding the ovaries during radiation, or moving the ovaries out of the radiation field, may protect them from the effects of radiation. Scientists are also exploring whether using drugs to suppress the activity of the ovaries during chemotherapy will make the ovaries less susceptible to damage by chemotherapy.[5] For women with certain types of cervical or ovarian cancer, fertility-preserving surgery may also be an option.[6] It’s important to understand that only specific subsets of patients will be candidates for these approaches, and that some of the methods are still in the early stages of evaluation.

Pregnancy after cancer

In addition to having concerns about their ability to get pregnant, women may have concerns about whether pregnancy after cancer treatment will be safe for themselves and their children. While there is a limited amount of information about these topics, the news is generally good.

The risk of cancer recurrence during or after pregnancy has been most studied in women with breast cancer, and these studies generally have reported that pregnancy does not increase the risk of breast cancer recurrence. [7] Many doctors, however, suggest waiting for a period of time after treatment before becoming pregnant. [8]

If chemotherapy or radiation therapy has damaged her heart or lungs, a woman may also have concerns about the strain that pregnancy will put on her body. Studies of breast cancer survivors suggest that long-term heart problems are uncommon after chemotherapy or radiation therapy, [9] but a woman may wish to talk with her doctor about her current health status and the likely effects of pregnancy.

Children born after their mother’s cancer treatment do not appear to be more likely than other children to have birth defects or cancer.[10] If a woman’s cancer was due to a hereditary cancer syndrome, such as Lynch syndrome (hereditary nonpolyposis colorectal cancer), her child may inherit the gene mutation responsible for her family’s increased risk of cancer. Talking with a genetic counselor may help clarify the child’s risk.

When planning for pregnancy, be aware that some cancer treatments may cause you to have an early menopause even if your periods resume after treatment. Also be aware that you may be capable of conceiving even if your periods do not resume; continue to use birth control if you do not wish to become pregnant.

Other Options for Parenthood

Not all women have the luxury of being able to explore their reproductive options before beginning cancer treatment, and not all women will find a fertility preservation option that meets their needs. But there are still ways to become a parent. Discussion of other routes to parenthood may be a painful topic for women who want to become pregnant and cannot. But as cancer survivors consider how best to build their families, methods such as adoption are important options.

Adoption: Couples and individuals who wish to adopt have a range of options, including different types of domestic and international adoptions. You may wish to start by learning about the adoption laws in your state and by talking with other adoptive parents about the professionals and agencies they worked with. Before selecting an adoption agency, women may wish to talk with them about their attitudes toward placing a child with a cancer survivor. Many agencies will be receptive toward this, but it’s important to know before making a final decision.

Egg Donation: Women who still have a uterus may be able to become pregnant using an egg donated by another woman. Through in vitro fertilization, the donated egg would be fertilized by the cancer survivor’s male partner or a sperm donor, and implanted in her uterus. Alternatively, another couple may donate a frozen embryo that could be implanted in her uterus.

Gestational Carrier or Surrogate: Women who do not have a uterus, or who are otherwise unable to sustain a pregnancy, may be able to have another woman carry a pregnancy for them. If the cancer survivor has functioning ovaries, her own egg can be fertilized by her male partner’s sperm and transferred to the uterus of another woman. In this case, the woman who carries the pregnancy is known as a gestational carrier. If the cancer survivor does not have functioning ovaries, another woman can both donate an egg and carry the pregnancy. This is the arrangement traditionally known as surrogacy.

Individual Decisions Within a Larger Community

The decisions that you make about building a family (or about coming to terms with not building a family) will be intensely personal, but know that you are part of a larger community of patients and healthcare providers who are grappling with these issues.

To think about future parenthood is to think about life after cancer. For many people with cancer, planning for the future may provide the motivation needed to get through treatment.

More Information?

Discuss with others….. http://cancerconnect.com/groups/young-adults/topics/fertility-after-cancer-treatment

Fertile Hope (www.fertilehope.org) provides a range of fertility resources for people with cancer.

References:

A growing body of evidence suggests that aspirin may reduce the risk of several types of cancer, with particularly strong evidence for colorectal cancer. Not all studies have found a benefit, however, and any potential benefits of aspirin must be weighed against risks such as bleeding.

To further explore the relationships between daily aspirin and cancer, researchers conducted a combined analysis of 51 previous randomized trials.[1] The trials were originally designed to evaluate the effect of daily aspirin on outcomes such as heart disease, but information about cancer was also available.

• Daily aspirin reduced cancer deaths. After five years, aspirin users had a 37 percent reduction in risk of cancer death.
• Aspirin also reduced the likelihood of developing cancer. From three years onward, aspirin users had a 24 percent reduction in the risk of being diagnosed with cancer.
• As expected, aspirin carried a risk of major bleeding, but this risk appeared to diminish over time.

Another study published in the same issue of The Lancet evaluated the effect of daily aspirin on cancer metastasis (the spread of cancer from its original site to other parts of the body). The study focused on 987 people who were diagnosed with cancer while participating in one of five trials of aspirin use. Those who were taking aspirin were less likely to have metastatic cancer than those who were not taking aspirin.[2]

These results suggest that regular aspirin use may reduce cancer incidence and mortality, but concerns remain about the risks of regular aspirin use in healthy individuals. People who are considering using aspirin on a regular basis are advised to discuss the risks and benefits with their physician.

References:

Dr. Cassileth is a world-renowned authority in integrative medicine. She is a researcher, educator, and planner who has worked in complementary (integrative) medicine and the psychosocial aspects of cancer care for more than 25 years.  She has just released a new book, The Complete Guide to Complementary Therapies in Cancer Care. MSKCC’s Integrative Medicine Service’s Web site, www.MSKCC.org, offers evidence-based information about herbs, vitamins, and unproved cancer treatments at no charge to professionals and the public.

Integrative medicine combines modern scientific treatment with complementary therapies that can transform the physical, emotional, and spiritual lives of people living with chronic or life-threatening illness. Complementary therapies such as touch therapies, mind-body therapies, acupuncture, nutrition, and physical activity are not substitutes for mainstream medical care. But when used in concert with medical treatment, they alleviate stress; reduce pain, anxiety, and other physical and emotional symptoms; and enhance quality of life.

On Thursday, November 17, 2011 at 6:00 PM EST you’ll have the opportunity to hear a brief presentation and to ask the expert, Dr. Barrie Cassileth, about helpful, evidence-based complementary therapies. You’ll learn how to recognize bogus “treatments” you will want to avoid.

Click here to submit a question for the Q&A portion of the Web Chat or to register for the Web Chat. Please note, Dr. Cassileth will address as many questions as possible during the 30-minute live Q&A portion of the Web Chat. Thank you for your participation.

Medullary thyroid cancers account for approximately 2-3% of all thyroid cancers. These cancers tend to have a somewhat worse prognosis than more common types of thyroid cancer, and up to 25% of cases are thought to be hereditary. When possible, treatment involves surgery to remove the thyroid gland. Conventional chemotherapy has limited effectiveness against medullary thyroid cancer, and there is growing interest in newer, targeted drugs.

Cabozantinib targets specific biological pathways (the MET and VEGFR2 pathways) that contribute to the growth of several types of cancer.

To evaluate cabozantinib for the treatment of medullary thyroid cancer, researchers conducted an international Phase III clinical trial known as EXAM. The study enrolled patients with worsening, advanced medullary thyroid cancer that could not be surgically removed. Study participants were treated with either cabozantinib or a placebo.

Cabozantinib delayed the progression (worsening) of the cancer. Survival without cancer progression was 11.2 months in the cabozantinib group and 4.0 months in the placebo group. The effect of cabozantinib on overall survival is also of interest, but longer follow-up will be necessary before overall survival can be assessed.

More complete results are expected to be presented at an upcoming medical conference.

Reference: Exelixis press release. Exelixis’ cabozantinib meets primary endpoint in phase III clinical trial for medullary thyroid cancer. October 24, 2011.

To start with the more familiar term, genetics is the study of single genes and their effects.[1] For example, certain inherited mutations in the BRCA1 or BRCA2 genes greatly increase a woman’s risk of breast and ovarian cancer. Mutations in these genes can be passed down through either the mother’s or the father’s side of the family. If a woman tests positive for a BRCA mutation, there are steps that she can take to reduce her cancer risk or to detect cancer at an early stage.

Genomics generally refers to the study of the study of the entire genome (all of the DNA in an organism). Genomics can consider multiple genes and how they interact with each other and the environment to affect health. Examples of genomic tests are the Oncotype DX breast and colon cancer tests. The tests evaluate the activity of several genes in a sample of tumor tissue in order to assess the likelihood of cancer recurrence. Information about recurrence risk can affect treatment decisions.

Similarly, research that combines genomics with pharmacology (pharmacogenomics) is studying how genetic variation affects an individual’s response to particular medications. Variability in genes involved with drug metabolism can have a substantial effect on drug response and drug side effects. Progress in this area is likely to contribute to more individualized, more effective, and less toxic drug treatments.

In short, research in genomics is expanding at a rapid rate and will have a profound effect on many aspects of disease prevention, diagnosis, and treatment. Diseases such as cancer are remarkably complex; genomics provides researchers and physicians with tools to explore and address these complexities.

Reference:

Since relatively few women are diagnosed with cancer during pregnancy, data regarding the effects of chemotherapy during pregnancy are limited. Determining whether women can safely receive chemotherapy during pregnancy is important because postponing chemotherapy until after delivery may worsen outcomes for the mother.

To evaluate the health and development of children born to women who received chemotherapy while pregnant, researchers conducted a study among 70 children. The age of the children ranged from 18 months to 18 years. The average follow-up time at this point is two years, although some children have been followed for much longer.

The most common type of cancer among the mothers was breast cancer. Other types of cancer were leukemias and lymphomas, ovarian cancer, cervical cancer, brain cancer, skin cancer, colorectal cancer, nasopharyngeal cancer, and Ewing’s sarcoma.

The children were born at an average of 35.7 weeks of gestation. Seven children were born very early (28-32 weeks), nine were born early (32-34 weeks), 31 were preterm (34-37 weeks), and 23 were term (37 weeks or more).

• The frequency and types of birth defects were similar to what is seen in the general population. No heart abnormalities were detected.
• Growth and general health and development were similar to what is seen in the general population.
• The cognitive development of most children was in the normal range. Those who fell below the normal range tended to be children who were born early.

These results suggest that children who were exposed to chemotherapy before birth tend to do as well as children in the general population. Chemotherapy did not appear to adversely affect the heart or mental processes. Women are advised to talk with their doctor, however, about the possible side effects of any drug or supplement taken during pregnancy.

Given the effect that early delivery had on cognitive development, the researchers note that it’s important to avoid preterm birth if possible.

The researchers will continue to follow the children enrolled in this study in order to assess the long-term consequences (if any) of in-utero exposure to chemotherapy.

Reference: Amant F, Van Calsteren K, Halaska M et al. Cognitive and cardiac outcome after prenatal exposure to chemotherapy in children 18 months or older. Presented at the 2011 European Multidisciplinary Cancer Conference. Stockholm, Sweden. September 23-27, 2011. Abstract LBA12.