ABSTRACT
Objective To investigate the impact of prior non-pancreatic cancer on the survival outcomes of patients with localized pancreatic neuroendocrine tumors (PanNETs). Methods We reviewed the Surveillance, Epidemiology, and End Results database and selected patients with localized PanNETs diagnosed between 1973 and 2015. We divided the patients into two groups according to the presence or absence of prior non-pancreatic malignancy. Before and after propensity score matching, we compared the clinicopathological characteristics and studied the overall survival and cancer-specific survival. Results A total of 357 (12.9%) of 2778 patients with localized PanNETs had prior cancer. A total of 1211 cases with only a localized PanNET and 133 cases with a localized PanNET and prior cancer had complete data and met the inclusion criteria of the current study. Patients with prior cancer were associated with advanced age (>65 years, 57.9% prior cancer
Subject(s)
Aged , Female , Humans , Male , Multivariate Analysis , Neoplasms, Second Primary , Neuroendocrine Tumors/epidemiology , Pancreatic Neoplasms/epidemiology , Propensity ScoreABSTRACT
Objective To establish a nomogram for predicting the distant metastasis risk of pancreatic neuroendocrine tumors (pNETs) in elderly patients. Methods We extracted data of patients with diagnosis of pNETs at age ≥65 years old between 1973 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. All eligible patients were divided randomly into a training cohort and validation cohort. Uni- and multivariate logistic regression analyses were performed on the training cohort to identify independent factors for distant metastasis. A nomogram was developed based on the independent risk factors using rms packages of R software, and was validated internally by the training cohort and externally by the validation cohort using C-index and calibration curves. Results A total of 411 elderly patients were identified, of which 260 were assigned to training cohort and 151 to validation cohort. Univariate and multivariate logistic regression analyses indicated the tumor site (body/tail of pancreas: odds ratio [