Pancreatic Schwannomas:a Comprehensive Review Of The Literature

Aims:Pancreatic schwannoma is one type of extremely rare neurogenic tumor, rarely reported by domestic and foreign paper. Accurate diagnosis is very difficult to be obtained before surgery. In order to improve the understanding of this disease, we try to conduct a comprehensive review of the Chinese and English literature.Materials and Methods:The study included patients diagnosed as primary pancreatic schwannoma by pathological examination of surgical specimens at the First Affiliated Hospital, Zhejiang University College of Medicine, between January 1,2006 and December 31,2015. We collected these patients’clinical data for statistical analysis. We also retrieved the Chinese pancreatic schwannoma literature in China National Knowledge Infrastructure (CNKI) and Wan fang database, as well as the English literature in Pubmed and Web of science database. The clinical data of these relevant cases were then collected and analyzed.Results:General information:Five patients were pathologically diagnosed as pancreatic schwannoma. Two were males (40%) and three females (60%), with the age between 25-62 years old, whose average age was 52 years. Clinical manifestations:Two patients (40%) showed repeating abdomen pain. The rest three patients (60%) were asymptomatic and found by physical examination. Diagnostic methods:All five patients accepted not less than two kinds of preoperative imaging examinations such as ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI), while accurate diagnosis was not obtained. All five patients were finally diagnosed by histopathological and immunohistochemical examination. Treatment and Prognosis:All the patients were performed surgery. One underwent spleen preserving resection of pancreatic body and tail (20%). One underwent pancreaticoduodenectomy (PD) and pancreatic peripheral nerve excision (20%). One underwent segmental resection of pancreas (20%). The rest two patients accepted enucleation (40%). One patient was lost to follow-up, and four patients had satisfying prognosis during the follow-up period. Only 64 and 11 cases were reported in the English and Chinese literature, respectively.Conclusions:Pancreatic schwannomas are extremely rare. As well as we know, only 80 cases have been found in our hospital, the English and Chinese literature. The age span of the patient is large. Incidence of the disease is similar between male and female. The disease was found usually because of abdomen pain or by physical examination. It is hard to obtain accurate diagnosis by preoperative imaging examinations. Surgery methods are various according to the location, size and nature of the tumor. Most cases are benign and have satisfying prognosis.