Merkel Cell Carcinoma (MCC) is a very rare and aggressive skin cancer that usually develops when a person is in his or her 70s. It is deadlier than melanoma, is known to metastasize quickly, has a high recurrence rate, and affects men more than women.
MCC is most prevalent in areas of the skin exposed to the sun. In fact the head and neck are the most commonly reported areas. Although it can develop a number of ways, the most common manner is by way of a polyomavirus. It doesn’t much matter though the origin of the tumor, this is a highly malignant and aggressive cancer.
The reader might be wondering if MCC is considered a cutaneous lymphoma of T-cell origin or even B-cell origin; after all, this is a lymphoma site. MCC is not a lymphoma. But it does have a strange association with blood cancers.
Specifically, while the average age for most people to develop MCC is 72, the age is much lower in people who are immunocompromised. People who are organ transplant recipients are at a 10-fold higher risk of developing MCC; people who have been diagnosed with HIV/AIDS are at a 13-fold higher risk, and finally, those patients with chronic lymphocytic leukemia (CLL) are at a 30-fold increased risk. To wit, these people tend to develop MCC about 20 years sooner than the general population.
It is not known precisely what the connection or association is. However, one possible link might be found in the fact that both CLL and MCC have been closely associated with so-called P53 genetic mutations. Since s
o many cases are caused by the Merkel cell polyomavirus, it’s possible that it is merely an opportunistic infection.
Whatever the case, the fact of the matter is that a diagnosis of MCC is a very serious matter, whether or not the patient has CLL or SLL. The disease lacks clinical symptoms meaning that it is often not found until it has spread to distant parts of the body.
Most recommendations include surgical excision of the skin tumor, along with radiotherapy and maybe chemotherapy. However, survival rates are currently rather low and people with CLL/SLL should have any suspicious skin sores or lesions seen by their physician as soon as possible.
[The accompanying photo, from Wikipedia, shows Merkel cell carcinoma on the individual's left arm.]
Hasan S et al. The role of postoperative radiation and chemoradiation in Merkel cell carcinoma Front. Oncol. 14 Nov 2013.