Dear Dr. Roach: I am a 70-year-old woman who has led a healthy, active life. There is a history of cancer on both sides of my family. I’ve been seeing my dermatologist for seborrheic keratoses for many years. The “seb Ks” that have been biopsied were all been benign. In the past several months, they have grown to be very large or small warts that cover my arms and back. They itch terribly.
A (different) dermatologist I was seeing for a clinical trial for the seb Ks told me about the Leser-Trelat sign and recommended that I see my primary care physician for a clear diagnosis. My physician did blood work, and all came back normal. The dermatologist said that there’s more testing to do and recommended I have a CT scan of my upper body/pelvis to accurately diagnose the condition.
What are your thoughts, and what is the course of action you recommend?
Anon.
The skin can often give clues to medical illnesses inside the body. One unusual case is the sign of Leser-Trelat, which is the explosive onset of multiple seb Ks. These are common, benign skin growths that are usually light brown, but can be dark brown or black with a bumpy, wart-like surface and a stuck-on appearance.
Many people get these, but the sudden appearance of many of them, particularly when they itch and the underlying skin is inflamed, can herald an internal cancer — especially gastrointestinal cancers. However, some people get this abundance of seb Ks in the absence of any illness, with benign tumors, or with pregnancy.
I have only seen this sign once in my career, and in that case, it was also associated with another skin condition called acanthosis nigricans. This is another benign condition consisting of a dark, velvety change of the skin of the neck, underarm and groin. This is usually associated with diabetes, but when it occurs with seb Ks, it is a more concerning sign for cancer. I had a discussion with the patient, who did want to have the CT scan done. The CT scan is a lot of radiation — the equivalent of over 2,000 X-rays, or the amount you would get from the environment in seven years. It is still low-risk, but not zero. (The patient never had cancer.)
There is not a right answer for everyone. Since it sounds like your seb Ks didn’t suddenly arrive but have suddenly changed, the CT scan is worth careful consideration, especially considering your family history. You should certainly have a colonoscopy if you aren’t up to date.
Dear Dr. Roach: Could you please recommend the best treatment for colon cancer after surgery, when only 1 out of 39 lymph nodes had cancerous cells?
H.L.
Surgery remains the primary way to cure colon cancer, which is why screening is so important. The sooner the cancer is found, the better.
When a lymph node is present, chemotherapy is recommended to eradicate any cancer cells that may have spread but are too small to see. Chemotherapy after surgery increases the cure rate in people with even a single cancerous lymph node. The benefit is not huge — somewhere between 3% and 8% of people will be cured by chemotherapy who would not have been cured without it.
Your oncologist will recommend a chemotherapy regimen, which should ideally begin within eight weeks after the surgery (as long as the person has recovered enough from the surgery to tolerate it).
Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to [email protected]
