Radio-induced malignancies of the scalp in adult after depilatory radiotherapy for tinea capitis in childhood: 137 cases

Abstract Introduction: Radiation-induced malignancies are the most feared complications of radiotherapy. Depilatory radiotherapy for ringworm of the scalp in childhood was the cause of an increase in the incidence of skin tumours of the scalp in adults. The aim of our study was to describe the epidemiological, clinical and therapeutic characteristics of radiation-induced skin tumours of the scalp in order to highlight the characteristics of these tumours compared to non-radiation-induced tumours. Methods: This is a bi-centric retrospective study, extending over a period of 41 years, which collected 137 patients with 200 tumours of the scalp. These patients were selected after noting a history of depilatory radiotherapy for ringworm in childhood in the clinical records of all patients with scalp tumours. We studied the epidemiological, clinical, therapeutic and evolving characteristics of this population. Results: The average age of consultation was 56·6 years. The sex ratio M/F was 3. Radiation dermatitis was found in 33% of cases. The average latency between depilatory radiotherapy and the appearance of radiation-induced tumours was 42·6 years. Multiple carcinomas (>2 tumours) were observed in 23·3% of cases. In 73% of cases, ulceration was the most frequent macroscopic aspect. The predominant histological type was basal cell carcinoma in 82% of cases. Radiation therapy has been the main treatment modality in 77·3% of cases, followed by surgery in 43% of cases. The appearance of new tumours on the scalp was observed in six patients. Conclusion: Radiation-induced tumours of the scalp are comparable in epidemiological and clinical characteristics to non-radiation-induced tumours. However, they may represent a challenge in therapeutic care and require regular monitoring.