Sebaceous Carcinoma Associated with Seborrheic Keratosis

作者：Tsai Tsung Ming; Wu Yu Hung; Yang Kuo Chia; Yang Chia Yi; Tsai Tsung Hua^*; Chan Jung Yi

来源：Journal of Cutaneous Medicine and Surgery, 2010, 14(5): 240-244.

DOI：10.2310/7750.2010.09059

Background: The association of a seborrheic keratosis with other common cutaneous neoplasms such as basal cell carcinoma and Bowen disease has been reported, but the association between a seborrheic keratotis and a malignant neoplasm with sebaceous differentiation is very unusual.
Objective: We present a case of two contiguous neoplasms, a seborrheic keratosis and a sebaceous carcinoma, and discuss the possibility of malignant change in a seborrheic keratosis as an explanation for the findings.
Methods and Results: A 57-year-old man presented with an asymptomatic tumor on the skin of his abdomen that was composed of two separate but contiguous lesions. The central lesion, about 0 9 cm in diameter, was nodular, irregular, and reddish and was surrounded by a blackish lesion about 3 cm in greatest dimension. Histopathologic examination revealed that the plaque was composed of two different adjacent tumors, including a central portion showing findings consistent with a sebaceous carcinoma and a peripheral part showing a seborrheic keratosis
Conclusion: Although the association is likely to be a coincidence and probably represents a collision tumor, the possibility that the sebaceous carcinoma represents malignant degeneration of the seborrheic keratosis cannot be entirely excluded.

• 出版日期2010-10