Perianal and Perineal Rhabdomyosarcomas - A Retrospective Multicenter Study of 35 Cases

Abstract

Purpose: Perianal/perineal rhabdomyosarcoma (PRMS) is rare, easy to be misdiagnosed and has poor prognosis. This study was designed to analyze the clinical, diagnostic, pathological and prognostic features of PRMS, and to explore its therapeutic modality.Methods: Clinical data of PRMS patients in the Sixth Affiliated Hospital and the Cancer Center of Sun Yat-sen University and related Chinese literatures published between 1987 and 2018 were described and analyzed. Chi-square test was used to test the differences between groups. The Kaplan-Meier methods were used to estimate and compare survival rates.Results: 35 patients, 20 identified in the Chinese literatures and 15 of our center from 1997 to 2019, were included in this study. 34 cases presented as perianal mass and one presented as inguinal mass. 20 patients complained about pain and 16 cases were misdiagnosed as perianal abscess, in which pain was found related to misdiagnosis (p＜0.05). The average time from symptoms to pathological diagnosis was 3.1 months. 13 cases were categorized into IRS group III/IV and 20 cases into stages 3/4. 14 Cases were diagnosed as embryonal rhabdomyosarcoma pathologically and 9 as alveolar rhabdomyosarcoma. Five patients survived for more than two years, three of them survived for more than five years. The overall survival rates of two years and five years were 32% and 24% respectively, in which misdiagnosis contributes to poor prognosis (p＜0.05). MRI showed that PRMS was closely related to external anal sphincter in 10 cases. Conclusion: PRMS is easy to be misdiagnosed, which could lead to worse outcome. Patients with painful perianal mass should be evaluated to exclude PRMS. MRI shows PRMS is closely related to external anal sphincter. Comprehensive therapy including radical operation and chemotherapy is recommended.

Perianal rhabdomyosarcoma in an adult: A case report and review of the literature

“…Previous studies documented that for patients with limited lesions and little or no involvement of external anal sphincter, local radical resection with anal preservation can be performed. [17] The studies advocate the combination treatment of PRMS, involving surgical excision, radiotherapy, chemotherapy, tumor-targeted therapy, and immune therapy. [18] The patient received molecular targeted therapy, chemotherapy, radiotherapy, immunotherapy, and surgery.…”