Rare Case of Basal Cell Carcinoma Plus Sebaceous Carcinoma After Mohs Surgery
Posted: Wednesday, December 8, 2021
A case study presented in Cureus examined a rare collision of basal cell carcinoma and sebaceous carcinoma, emphasizing the need to verify biopsy pathology during Mohs surgery when a frozen-section tissue evaluation shows disparate findings from the originally biopsied tumor. In addition, Joshua Spanogle, MD, of the Kansas City University Graduate Medical Education Consortium, and colleagues emphasized the importance of follow-up with permanent sections and immunohistochemistry when necessary.
“We advise caution to detect mimickers of basal cell carcinoma that warrant greater clinical workup,” the authors concluded. “Given the frequent periocular location of sebaceous carcinoma and the superior cure rate, we recommend Mohs micrographic surgery for sebaceous carcinoma.”
The authors described the case of a 76-year-old man with a history of basal cell carcinoma and sebaceous carcinoma. He first had Mohs micrographic surgery to extirpate a biopsy-proven basal cell carcinoma. Next, physicians performed Mohs surgery with frozen-section tissue; afterward, the first stage revealed atypical basaloid cells surrounding atypical foamy cells with scalloped nuclei at the deep margin. These atypical cells were cleared in the second stage.
Though a diagnosis of sebaceous carcinoma was favored based on the equivocal pathology on the frozen sections, these samples were sent to dermatopathology to confirm the tumor. A dermatopathologist then re-examined the initial biopsy slide and confirmed that nodular basal cell carcinoma was present. The first Mohs stage was then re-embedded for permanent sectioning and immunohistochemical staining. Sebaceous carcinoma at the deep margin was confirmed, and the presence of a particular focus of basal cell carcinoma extended into the superficial dermis.
The dermatopathologist concluded that the tumors were a collision lesion rather than a contiguous basal cell carcinoma with sebaceous differentiation.
Disclosure: The authors reported no conflicts of interest.