Considering Age-Related Issues With Cancer

February 19, 2019

Regardless of when patients receive their cancer diagnosis, their age affects the next step.

Younger Patients and Fertility

Every patient faces unique issues during and after treatment. In the past, oncologists focused primarily on treating the cancer, overlooking some issues related to the patient’s age. But now, doctors are increasingly concerned about the effect of treatment on a person’s future, including treatment-related long-term effects.Younger patients often have to contend with unique challenges, such as coping skills, social concerns, behavioral issues, employment matters and treatment-related infertility. Doctors should discuss these issues, particularly fertility preservation options with all fertile patients—male or female—and, in the case of children, with their parents or guardians.

A single cancer treatment can affect fertility, so it is essential that a patient’s doctor develop a fertility preservation plan before treatment begins. This might mean delaying treatment to accommodate fertility preservation methods, such as banking sperm or freezing fertilized eggs.

For example, prostate and testicular cancer therapies can affect sperm production, resulting in low sperm count or infertility. Banking sperm is a successful technique for men wanting to preserve fertility. If sperm count is low, a process called intracytoplasmic sperm injection requires only one sperm to fertilize an egg. Another technique is testicular sperm aspiration, in which sperm is taken directly from the testicle or from resected testicular tissue. It is used in men with low sperm count.

Kids and Adults: What’s the Difference?

The difference between childhood and adult cancers rarely comes down to simply age. Most tumors in children differ biologically from those in their adult counterparts and are typically due to the type of cell from which the cancer originates.

In the weeks after fertilization, the embryo develops into layers: ectoderm, mesoderm and endoderm. These layers lay the foundation for the development and maturation of tissues and organs in the body.

Adult cancers, such as lung, breast and colorectal, typically develop from epithelial tissue (adenocarcinomas), which come from the ectoderm or endoderm. Epithelial cells make up the skin and lining of the internal organs and glands. Alternatively, childhood cancers, including sarcomas (cancers of the bone or muscle) and leukemias (blood cancers), most often develop from the mesoderm.

Many childhood cancers form from primitive or embryonic cells found in developing fetuses and often manifest deep in the body. These cancers develop either because of genetics or an event in early fetal development, whereas adult cancers typically result from an accumulation of mutations caused by external sources, such as smoking or sun overexposure.

Researchers believe biological differences could point to why childhood cancers are often more responsive to chemotherapy, which is designed to target rapidly dividing cells. Epithelial cells are normally resilient because they are exposed to environmental influences, making them more resistant to treatment if they become cancerous. Vulnerable childhood cancer cells, however, are ideal targets for chemotherapy. Indeed, childhood cancer survivors are less likely to have a recurrence than adults. The five-year survival rate for all childhood cancers is higher (more than 80 percent compared with 68 percent).

For women, certain chemotherapy drugs and hormone treatments, as well as radiation to the pelvic area, can damage the ovaries and other reproductive organs and cause early menopause. Because women are born with a limited number of eggs, or oocytes, damaging them during cancer treatment can leave a woman infertile.

If treatment calls for radiation to the pelvis, the ovaries can be surgically moved away from the radiation field, called oophoropexy, which reduces the risk of damage by 50 percent. Treatments that temporarily shut down ovarian function during chemotherapy are also being studied as a means to prevent damage to eggs.

With in vitro fertilization (IVF), an egg is fertilized in the lab and frozen, or cryopreserved, and later thawed and inserted into the uterus. Egg retrieval must be done before treatment and could require several weeks to obtain viable eggs. Hormone injections might be given to promote egg development, but natural methods are also available. IVF can be performed with donor sperm and embryos.

While freezing unfertilized eggs is possible, the success rate is lower than it is for freezing embryos. Once thawed, the egg is fertilized by intracytoplasmic sperm injection and inserted into the uterus, and better freezing and fertilization techniques are improving success rates. Researchers are also exploring ways to freeze testicular and ovarian tissue to be transplanted back into the patient after therapy.

Older Patients and Comorbidities

Insurance coverage of fertility procedures varies, and the cost can be high. Depending on insurance coverage, some treatments might be provided, especially if they are part of a necessary medical procedure being performed anyway.Cancer is primarily a disease of aging. For many common cancers, the development of a tumor takes considerable time, dependent on a series of often unrelated events at the cellular level. Over the course of years, genetic and environmental toxins, such as tobacco, can cause DNA-damaging effects on cells. Meanwhile, the body’s ability to repair damaged cells appears to decline with advancing age. At the same time, the aging tissue around those damaged cells appears to play a role, creating a more conducive environment in which malignancies can grow. As cells age and stop dividing, it’s speculated that they develop a microenvironment that fosters cancer’s development. Another potential contributory factor, researchers say, is the declining immunity that naturally occurs with advancing age.

To complicate matters, many older people who receive a cancer diagnosis already suffer from at least one other illness, or comorbidity, such as heart disease, diabetes, hypertension or arthritis — some of which could be life-threatening.

Comorbid illness affects all aspects of cancer care, from early diagnosis to treatment options and prognosis. In fact, as cancer patients are living longer, comorbid illnesses have an even greater effect on long-term health.

Research has shown that patients with pre-existing illnesses were less likely to survive their cancer and at greater risk for recurrence.

To get appropriate and effective cancer treatment, patients should be evaluated, not only in terms of the physical effects of the cancer, but also for any other health issues they might have. Cancer drugs often have side effects that aggravate other medical conditions, and drug contraindications can create additional problems.

For example, one proteasome inhibitor is effective at treating multiple myeloma and mantle cell lymphoma, but can cause pain and numbness in the hands and feet—a condition known as neuropathy — that could be worse in people with diabetes, who are prone to nerve damage.

Hormone therapy, such as aromatase inhibitors for breast cancer, blocks the production of estrogen. Because estrogen helps maintain healthy bones, blocking it can lead to a higher risk of developing osteoporosis and cause problems if a patient already has osteoporosis.

Other cancer drugs, including monoclonal antibodies for HER2-positive breast cancer and anthracyclines for leukemia and some solid tumors, could worsen heart conditions, which are more common among older people. These drugs can injure the heart muscle, so patients must be monitored closely, and the dose of the drug might be limited according to heart function.

Side effects do not mean certain cancer drugs cannot be given if patients have another illness. Instead, doctors might adjust the dosage of medication — both for the cancer and other illnesses — so patients can receive the most effective cancer therapy. Older cancer patients should not automatically receive less aggressive therapy than younger patients. Age no longer matters as much as general fitness when it comes to eligibility for cancer treatment. Despite the prevalence of other common illnesses and the perception that older people are less likely to benefit from and cope with the stress of treatment, they typically fare equally well in overall survival and quality of life as their younger counterparts.


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