The effect of radiation therapy on microcystic adnexal carcinoma: A case report

BACKGROUND: Microcystic adnexal carcinoma (MAC) is a rare, locally aggressive tumor. Treatment for this neoplasm typically requires extensive local excision leading to morbidity. Therefore, the temptation to use alternative treatment options remains high. METHODS: We report one case of a nasal dorsum MAC treated with external beam radiation secondary to the patient's poor health status and preference. RESULTS: After initial dramatic clinical resolution, the tumor recurred in a clinically more extensive and histologically more aggressive form. CONCLUSION: On the basis of this case and several detailed in the literature, we therefore hypothesize that radiation therapy is not only an ineffective treatment for MAC, but evidence exists that this modality may induce conversion to a histologically and clinically less favorable neoplasm.