Using a Nomogram to Preoperatively Predict Distant Metastasis of Pancreatic Neuroendocrine Tumor in Elderly Patients.

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 [OR]=2.282; 95% confidence interval [CI]: 1.174 - 4.436, P<0.05), histological grade (poorly differentiated/undifferentiated: OR=2.600, 95% CI: 1.266-5.339, P<0.05), T stage (T2: OR=8.913, 95% CI: 1.985-40.010, P<0.05; T3: OR=11.830, 95% CI: 2.530-55.350, P<0.05; T4: OR=68.650, 95% CI: 8.020-587.600, P<0.05), and N stage (N1: OR=3.480, 95% CI: 1.807-6.703, P<0.05) were identified as independent risk factors for distant metastasis of pNETs in elderly. The nomogram exhibited good predicting accuracy, with a C-index of 0.809 (95% CI: 0.757 - 0.861) in internal validation and 0.795 (95% CI: 0.723 - 0.867) in external validation, respectively. The predicted distant metastasis rates were in satisfactory agreement with the observed values by the calibration curves. Conclusion The nomogram we established showed high discriminative ability and accuracy in evaluation of distant metastasis risk in elderly pNETs patients, and could provide a reference for individualized tumor evaluation and treatment decision in elderly pNETs patients.

Does Prior Cancer Have an Influence on the Survival Outcomes of Patients with Localized Pancreatic Neuroendocrine Tumors?

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 vs. 31.0% no prior cancer, P<0.001), later year of diagnosis (87.2% vs. 80.2%, P=0.049), a higher proportion of poorly differentiated/undifferentiated grade tumors (4.5% vs. 1.5%, P=0.025), and a higher proportion of no primary site surgery (19.5% vs. 10.4%, P=0.003). Prostate (29.32%), breast (18.05%), other genitourinary and retroperitoneal (16.54%), and gastrointestinal (12.78%) cancers were the most common prior cancer types. Most of the prior cancers (95.49%) were localized and regional, and only 4.51% of the prior cancers were distant. Patients with interval periods between the prior cancer and PanNET of ≤36 months, 36-60 months, 60-120 months, and >120 months accounted for 33.08%, 13.53%, 24.06%, and 29.32% of all cases with prior cancers, respectively. Univariate and multivariate Cox proportional hazards analyses were performed. The presence/absence of prior cancers did not impact survival outcomes of patients with localized PanNETs before and after propensity score matching (PSM). Further subgroups analysis showed that, patients with localized PanNETs and prior distant cancer had worse cancer-specific survival than patients with prior local/regional cancer or patients without prior cancer (P<0.001). No significant differences in cancer-specific survival were observed in terms of the different sites of the prior cancers and the different interval periods of prior cancers and PanNETs (P<0.05). Conclusions Patients with localized PanNETs and a history of prior cancer had survival outcomes that were comparable to those of patients with no history of prior cancer. Patients with localized PanNETs and prior cancer could be candidates for clinical trials if they satisfy all other conditions; aggressive and potentially curative therapies should be offered to these patients.

Impact of a Prior Nonpancreatic Malignancy on Survival Outcomes of Patients With Stage IV Pancreatic Neuroendocrine Tumor: A Population-Based and Propensity Score Matching Study.

OBJECTIVE: The aim of the study was to investigate the impact of a previous nonpancreatic malignancy on the survival outcomes in patients with a stage IV pancreatic neuroendocrine tumor (PanNET). METHODS: The Surveillance, Epidemiology, and End Results database was reviewed, and patients diagnosed with a stage IV PanNET between 2004 and 2015 were selected. Patients were divided into 2 groups according to the presence or absence of a previous nonpancreatic malignancy. Clinicopathological characteristics and survival outcomes were compared. RESULTS: A total of 1582 patients with stage IV PanNET were identified, of whom 116 (7.3%) had a prior malignancy. Prostate (33.62%), breast (17.24%), and gastrointestinal (12.07%) malignancies were the most common. Most prior malignancies (84.48%) were localized and regional. Patients with intervals of 36 months or less, 36 to 60 months, 60 to 120 months, and more than 120 months account for 25.86%, 14.66%, 31.03%, and 28.45% of all cases, respectively. Before and after propensity score matching, there was no significant difference detected regarding survival outcomes. CONCLUSIONS: Stage IV PanNET patients with a history of a prior cancer had comparable survival outcomes with patients without such history. These patients could be candidates for clinical trials if otherwise appropriate, and aggressive and potentially curative therapies should be offered.

Nomograms predict survival outcomes for distant metastatic pancreatic neuroendocrine tumor: A population based STROBE compliant study.

As a rare malignant tumor, pancreatic neuroendocrine tumor (pNET) has very low incidence. However, most of the pNET patients would develop the distant metastasis, which significantly reduces patients' survival rate. Therefore, it is very important to construct a prognostic model of pNET patients with distant metastasis based on a large database to guide clinical application and treatment. The aim of this study is to establish nomograms for cancer-specific survival (CSS) and overall survival (OS) of patients with distant metastatic pNET based on the Surveillance, Epidemiology, and End Results (SEER) database.SEER were reviewed and the patients with pNET diagnosed between 1973 and 2015 were selected. After screening, a total of 624 cases were included in the study. Patients were randomly divided into a training cohort (n = 416) and a validation cohort (n = 208). Cox proportional hazard analysis revealed that age at diagnosis of ≥80 years, year of diagnosis, histological grade, and primary site surgery were independent factors both for CSS and OS. The nomograms indicated good accuracy in predicting 1-, 3-, and 5-year survival, with a C-index of 0.777 (95% confidence interval [CI], 0.743-0.811) for CSS and 0.772 (95% CI 0.738-0.806) for OS in training cohort. In the validation cohort, the C-index was 0.798 (95% CI 0.755-0.841) for CSS and 0.797 (95% CI 0.753-0.841) for OS. The calibration curves showed satisfactory consistency between predicted and actual survival.The study establishes excellent prognostic nomograms for CSS and OS for pNET patients with distant metastasis. They can be used to accurately predict survival rate, and provide useful information to physicians and patients.

Clinicopathological features and prognosis factors for survival in elderly patients with pancreatic neuroendocrine tumor: A STROBE-compliant article.

To investigate the features and prognosis of the elderly patients with pancreatic neuroendocrine tumor (pNET).The patients diagnosed with pNETs between 2004 and 2014 were identified from the Surveillance Epidemiology and End Results database. The ethical approval was waived because the present study was analysis of the data from Surveillance Epidemiology and End Results database.A total of 4608 patients with "one primary only" histologically pNETs were confirmed and 653 were older than 75 years. Cancer-specific survival (CSS) and overall survival (OS) were examined. The elderly patients (≥75 years) have disadvantage in CSS and OS compared with younger cohort. Multivariate logistic regression revealed that the elderly patients have increased poorly differentiated composition, and decreased proportion of Black patients, receipt of surgery, married status, and number of removed lymph node. Multivariate Cox regression analysis demonstrated worse differentiation. Patients of T3-4 and M1 stage were associated with poor CSS, while patients of being female, tumor locating at pancreatic body/tail, receipt of surgery, and being married were associated with better CSS in the elderly patients. Meanwhile, patients with higher histological grade and M1 stage have poor OS, while patients with the characteristics of female, being married, tumor location at pancreatic body/tail and tumor surgery have better OS. Distant metastatic elderly patients underwent primary site surgery had better CSS and OS than the patients without surgery.The elderly patients have increased possibility of poorly differentiated tumor, and decreased proportion of Black patients, surgery of primary site, number of removed lymph node and married status. Worse differentiation and tumor metastasis were independent risk factors for both CSS and OS, while primary tumor located in body/tail of pancreas, female patients, surgery of tumor primary site, and being married were protective factors.