Pilonidal sinus disease carcinoma: Survival and recurrence analysis

Background The study aims to determine the survival and recurrence rates of pilonidal sinus disease (PSD) carcinoma. Methods The data were collected retrospectively by searching the worldwide literature for all reports of carcinoma developing on the background of PSD. The results were presented using Kaplan–Meier curves. Results Between 1900 and 2022, 140 cases of PSD carcinoma were published in 103 papers, with follow‐up data available in 111 cases. Squamous cell carcinoma constituted 94.6% of the cases ( n = 105). The disease‐specific survival rate was 61.7% for 3 years, 59.8% for 5 years, and 53.2% for 10 years. There was a significant survival difference between stages: 80.0% in stages I and II, 70.8% in stage III, and 47.8% in stage IV ( p = 0.01). The 5‐year survival in G1‐tumors was better than G2 and G3‐tumors at 70.5% and 32.0%, respectively ( p = 0.002). Recurrence occurred in 46.6% of the patients. The time‐to‐recurrence in patients treated with curative intention averaged 15.1 months (1–132 months). Local, regional, and distant recurrence was observed in 75.6%, 33.3%, and 28.9% of the recurrent tumors, respectively. Conclusions Pilonidal sinus carcinoma has a worse prognosis than primary cutaneous squamous cell carcinoma. Poor prognostic factors include advanced‐stage disease and poor differentiation.