Successful Radiotherapy in Management of Inoperable Trichoblastic Carcinoma: A Case Report.

BACKGROUND Trichoblastic carcinoma (TC) is a rare adnexal tumor that usually occurs on the scalp and the face. Clinical presentation is nonspecific and can simulate basal cell carcinoma (BCC). Optimal treatment and outcomes remain unclear. Surgery remains the main treatment but can be difficult or impossible in locally-advanced situations. Thus, conservative options must be developed as TC affects elder populations, and radiotherapy may be a good conservative option but its use in TC is poorly documented. CASE REPORT We report a case of an 86-year-old man with an asymptomatic 5-cm tumor of the nose, extending to the right cheek and inner canthus. He was immunodeficient on kidney transplant and was treated by prednisone and tacrolimus. Biopsy confirmed the TC diagnosis. Surgery and brachytherapy were not possible due to clinical extension, advanced age, and comorbidities. External beam radiation with intensity modulated radiotherapy on tomotherapy was attempted. Seventy Gy was delivered in 35 fractions over 2 months 5/7 days. A bolus with ball (Seemed®) was used each treatment day to deliver an adequate dose of radiotherapy to the skin. Clinical examination at 1 month did not reveal any residual lesion and the patient remains in complete remission after 9 months of follow-up. Tolerance was characterized by grade 2 (NCI CTC AE V4) radiodermatitis, mucositis, and conjunctivitis, managed by local medications. CONCLUSIONS We report a rare case of locally-advanced TC, successfully treated by external beam radiation, which may be an acceptable alternative treatment for unresectable tumors.