Abstract
BACKGROUND: Data on clinical characteristics, treatment outcomes, and prognosis of pancreatic primitive neuroectodermal tumors (PNETs) are limited. AIM: To analyze the clinical data of 30 patients with pancreatic PNETs to identify their clinical characteristics and factors associated with prognosis. METHODS: We used the keywords "primary neuroectodermal tumor," "digestive tract," "pancreas," "pancreatic," and "gastrointestinal," individually or in combination, to collect data from a global database for all patients with pancreatic PNET to date. Univariate and Cox regression analyses were performed to identify prognostic factors for patient survival. RESULTS: A total of 30 cases of pancreatic PNET were included in this study: 15 males and 15 females with a mean age of 24 years. The main symptom was abdominal pain (73.3%), and the median tumor size was 7.85 cm. Twenty-four patients (80.0%) underwent surgery and nineteen patients received adjuvant therapy. Local metastasis was observed in 13 patients (43.3%), lymph node metastasis in 10 patients (33.3%), and distant metastasis in 6 patients (20.0%). Local recurrence was observed in 13 patients (43.3%). The median survival time of all patients was 29.4 months, and the overall estimated 1-year and 3-year survival rates were approximately 66.0% and 36.4%, respectively. Univariate analysis showed that chemotherapy (P = 0.036), local metastasis (P = 0.041), lymph node metastasis (P = 0.003), distant metastasis (P = 0.049), and surgical margins (P = 0.048) were the prognostic factors affecting survival. Multivariate analysis revealed only lymph node metastasis (P = 0.012) as a prognostic factor. CONCLUSION: Pancreatic PNET is extremely rare, occurs in young adults, has no apparent sex predisposition, has a high rate of metastasis and early recurrence, and has a very poor prognosis. The diagnosis of pancreatic PNET requires a combination of clinical symptoms, pathologic features, immunohistochemistry, and cytogenetic analysis. Univariate analysis suggested that chemotherapy, metastasis, and surgical margins were prognostic factors affecting survival, and multivariate analysis suggested that lymph node metastasis is an important prognostic factor. Therefore, early diagnosis, early and extensive resection, and adjuvant chemoradiotherapy may help improve prognosis.