Pilonidal Sinus Carcinoma: Review of Literature and Own Data

Abstract

Aim: to analyse and estimate the incidence of pilonidal cyst cancer from 2023 to 2024. Key points. In 2023, M. F. Safadi et al. published a review of the incidence of pilonidal cyst cancer, including 140 cases from 1900 to 2022. From 2023 to 2024, 14 observations of patients with malignant pilonidal cyst appeared in the literature. One case of malignant pilonidal transformation was reported in our practice. Patients’ age varied from 19 to 86 years (54.5 ± 11.9 years). Among the patients, males predominated — 88.9 % (137/154), the male: female ratio was 8.1 : 1. The time from the first diagnosis of a pilonidal cyst to the development of cancer in the cyst ranged from 1 month to 62 years. The mean interval from detection of pilonidal cyst to malignancy was 21.1 ± 13.6 years (median — 20.0 years). One of the reasons for malignant degeneration of pilonidal cysts may be the presence of concomitant hidradenitis suppurativa, which is included in follicular occlusion syndrome. However, the direct association of follicular occlusion syndrome with pilonidal cyst malignancy has not been definitively confirmed. Conclusion. Malignancy of pilonidal cysts is a rare complication of a long-term inflammatory process in the sacrococcygeal region. The authors concluded that it is necessary to emphasise the presence of a concomitant follicular occlusion syndrome in patients, which may alter the usual management tactics of pilonidal disease.

Keywords

• pilonidal cyst
• malignant transformation
• follicular occlusion syndrome
• epithelial coccygeal tract