Abstract:

Objective To investigate the clinical characteristics and factors of prognosis for peripheral primitive neuroectodermal tumors (pPNET). Methods The clinical data of 9 patients in clinics and medical records of 117 patients with pPNET reported by literatures were collected. The data of imaging, histopathology, immunohistochemistry, clinical features and treatment of patients with pPNET were analysed. Kaplan-Meier method was employed to calculate the 1-year, 3-year and 5-year survival rates of patients, and the factors of prognosis were analysed. Log-rank tests were used for univariate analysis, and Cox proportional hazards was adopted for multivariate analysis. Results There were 65 males and 61 females, with the average age of (29.90±16.06) years. There were 35 cases (27.8%) with stage I, and the percentages of stageⅡ, Ⅲ, and Ⅳ were 42.1%, 8.7% and 21.4%, respectively. One hundred and ten patients received surgical treatment, radical surgery was performed in 88 patients, and 12 patients underwent surgery after neoadjuvant chemotherapy. Thirty-two patients (25.4%) received adjuvant radiotherapy, and 61 patients (48.4%) underwent adjuvant chemotherapy. Forty-seven patients received first-line chemotherapy, among whom 37 received second-line or more than second-line salvage therapy. The mean follow-up duration was 19.0 months. Relapse occurred in 52 patients, and there were 38 cases of death. The 1-year, 3-year and 5-year survival rates were 54.8%, 15.9% and 3.2%, respectively. Univariate analysis revealed that tumor size, lymph node status, distant metastasis and stage were significant prognostic factors, and multivariate analysis indicated that complete surgery was an independent prognostic factor. Conclusion Comprehensive therapy is the main treatment for pPNET, and complete surgery is an important prognosis factor.

Key words: peripheral primitive neuroectodermal tumors, treatment, prognostic