Cancer

Can you address some of the most common myths about skin care?

DEAR DOCTOR K: I hear and read so much advice about skin care, and I don't know what's true and what's not. Can you address some common myths about skin care?

DEAR READER: You're right to be skeptical. My patients often tell me that they've heard about a way to keep their skin clear and healthy, and often it is simply not true. I'll debunk some of the most common myths I hear.

How does chemotherapy fight cancer?

DEAR DOCTOR K: My mother was diagnosed with cancer and will soon begin chemotherapy. I'd like to understand how chemotherapy is given, and how it fights cancer.

DEAR READER: Chemotherapy uses drugs that kill cancerous cells, but only injure healthy cells. To understand chemotherapy, you need to understand what cancer is and what is different about cancer cells.

Should I get a prostate cancer screening test?

DEAR DOCTOR K: I've heard so many conflicting opinions about whether or not to get screened for prostate cancer. Are there official guidelines? What do they recommend?

DEAR READER: To say that prostate cancer screening has been controversial is an understatement. I spoke to my colleague Dr. Marc Garnick, clinical professor of medicine at Harvard Medical School, to hear his thoughts.

I have dense breasts. Does that increase my risk of breast cancer?

DEAR DOCTOR K: My doctor says I have dense breasts, and a friend says that means I have an increased risk of breast cancer. I'm hoping you'll tell me that's not so.

DEAR READER: I wish I could fully reassure you, but I can't. A woman who has dense breasts does have a slightly increased risk of breast cancer, although not clearly an increased risk of fatal breast cancer.

Can you discuss hormonal therapy to treat prostate cancer?

DEAR DOCTOR K: My doctor has proposed androgen deprivation therapy to treat my prostate cancer. Can you tell me about this treatment?

DEAR READER: Androgens are the family of male sex hormones that includes testosterone. When prostate cancer develops, testosterone contributes to the growth and spread of the tumor. Androgen deprivation therapy deprives cancer cells of this stimulation. Also known as hormonal therapy, it can be a powerful weapon in the fight against prostate cancer.

Did cancer treatment increase my heart disease risk?

DEAR DOCTOR K: I survived cancer, only to be told that the treatments that saved my life may have increased my risk for cardiovascular disease. What are the risks? And can I minimize them?

DEAR READER: As more people are living longer after a cancer diagnosis, more people are coping with the long-term effects of cancer treatment. Many cancer-suppressing treatments can have undesirable effects, for example, on the heart and blood vessels.

What can elephants teach us about cancer?

DEAR DOCTOR K: I heard on the radio about a new research finding that elephants don't get cancer. If we could figure out why, could we protect ourselves against cancer?

DEAR READER: A recent study found that elephants (and many animals) do, in fact, get cancer, but have lower rates of death from it than humans do. The study also found one possible explanation that, as you suggest, might someday help us deal with cancer.

Does my son need to get the HPV vaccine?

DEAR DOCTOR K: A friend says that my young son should get the vaccine that protects girls against cervical cancer. That doesn't seem to make sense. Can you explain?

DEAR READER: Your friend is right, and here's why. The vaccine is against a virus called human papilloma virus (HPV). There are more than 100 strains of HPV; about 40 of these strains can be transmitted by sexual contact. So-called low-risk strains cause genital warts. High-risk strains can cause cancers of the cervix, anus, penis and throat. I'll call these the HPV-related cancers. Not all of these cancers are caused only by HPV, but the virus is an important cause of each. Most cases of cervical cancer in women in the United States are caused by HPV.

How does sun exposure damage our skin?

DEAR DOCTOR K: You've said many times that the sun can harm our skin and increase the risk for skin cancer. How does it do that?

DEAR READER: As you age, the single biggest cause of damage to skin is sun exposure. This damage is called "photoaging." Over the years, sun exposure causes fine and coarse wrinkles; baggy skin with a yellow, leathery appearance; and dry, scaly skin. It also reduces collagen, a natural chemical that gives strength to tissues and that supports a network of blood vessels in the skin. As a result, the skin bruises more easily.