Clinical Characteristics and Prognosis of Osteoclast-like Giant Cell Tumors of the Pancreas Compared with Pancreatic Adenocarcinomas: A Population-Based Study.

BACKGROUND The incidence of osteoclast-like giant cell tumor of the pancreas (OGTP) is very low, and relatively little OGTP clinical data is available. The present study, therefore, sought to conduct a more comprehensive analysis of the clinical characteristics and prognosis of OGTP. MATERIAL AND METHODS A large population-based cohort analysis was conducted using the Surveillance, Epidemiology and End Results (SEER) registry. We conducted a systematic assessment of the demographic and clinical characteristics of these patients, in addition to assessing available prognostic and therapeutic data corresponding to their disease. We further compared overall survival (OS) in these OGTP and pancreatic adenocarcinoma (PA) patient cohorts, adjusting for sex, grade, stage, and surgical treatment by propensity score matching (PSM). RESULTS We included a total of 47 OGTP patients and 73 150 PA patients in the present analysis. The mean ages of PA and OGTP diagnosis were 68.0 and 62.8 years, respectively. Compared with PA patients, OGTP patients were more likely to be female (70.2% versus 48.7%, P<0.01), to have early-stage disease, to have lower rates of lymph node metastasis (17.0% versus 28.8%, P<0.01) and distant metastasis (17.0% versus 45.1%, P<0.01), and to have higher rates of tumor resection (70.2% versus 15.4%, P<0.01). OGTP patients also had a significantly longer median OS than did PA patients (13 months versus 6 months; hazard ratio [HR] 0.55, 95% confidence interval [CI] 0.37-0.57, P<0.0001). No significant differences in tumor site preferences were detected. Our findings also suggested that being female, having early-stage disease, and undergoing surgical resection may be associated with a more favorable prognosis in patients with OGTP. CONCLUSIONS OGTP patients had distinctive clinical characteristics and a better prognosis compared with PA patients. Understanding these differences will help clinicians accurately recognize these diseases. Radical resection was beneficial to the survival of OGTP patients.