Cutaneous lymphoma, like all lymphomas, attacks either the B- or T-cell lymphocytes, white blood cells that help regulate the immune system. However, unlike most instances of lymphoma which occur first in the lymph nodes, cutaneous lymphoma forms in the skin. Comprising no more than five percent of all lymphoma diagnoses, cutaneous lymphoma therefore has some distinctive features that make cutaneous lymphoma prognosis a slightly more complicated question than it may first appear.
Of the cutaneous lymphomas, mycosis fungoides (also called granuloma fungoides or Alibert-Bazin sydrome) is the most common T-cell variety. Men are more prone to this cancer than women, and the average age of onset in between 50 and 60 years. It appears as a scaly, itchy red lesion. It can eventually protrude slightly from the skin. Prognosis is generally good when the tumor is detected early, and can be treated with topical chemotherapy or phototherapy.
If mycosis fungoides is left untreated, the patches will spread over the skin and the cancer will spread to the lymph nodes. This is Sezary Syndrome, and appears to be a very itchy, red sunburn. There is no cure for Sezary Syndrome, and prognosis is poor. It spreads quickly, but can be slowed with phototherapy.
Primary Cutaneous Follicle Center
For B-cell variant lymphoma, this is the most common. A tumor will typically appear on the head, neck, or trunk and will proceed to grow very slowly, sometimes taking months or years to develop. This tumor can usually be removed surgically and prognosis is good. Occasionally, chemotherapy and/or radiotherapy might be necessary.
Primary Cutaneous Marginal Zone B-cell
Another slow-growing cancer, this is the second most frequent type of B-cell cutaneous lymphoma. The nodules appear pink and may appear anywhere, though typically present on the arms or trunk. Otherwise it is very similar to primary cutaneous follicle center lymphoma. Prognosis is good, and this cancer can be left untreated until problems begin to develop.
Primary Cutaneous Diffuse Large B-cell Lymphoma
Affecting mostly older women, this is the most aggressive of all cutaneous lymphomas. It spreads quickly, over weeks, not years. Initially appearing as reddish or bluish lesions on the lower leg, these tumors will eventually penetrate deep into the fatty layers of the leg, and become open sores. The standard treatment is chemotherapy, but prognosis is usually very poor.
High magnification micrograph of cutaneous T-cell lymphoma by Nephron