Excisional biopsy of a solitary 1 cm diameter pigmented lesion from the upper back on your 38 year old female patient shows a malignant melanoma that is 2 mm in thickness, with margins clear. These findings most strongly suggests that:
A She will not have to worry further about this lesion
B The lesion has occurred in a non sun-exposed area
C There is a genetic basis for the occurrence of this lesion
D Human papillomavirus infection was present
E There may be metastases within 5 years
(E) CORRECT. This is very thick and suggests that there is a much poorer prognosis than a melanoma only 0.75 mm thick (which has a 98% 5 year disease free interval.
M.D., PGY-3 Internal Medicine