Background: Liver transplantation (LT) has been accepted as a treatment in selected cases of neuroendocrine tumors (NETs) with hepatic metastases.
Patients and methods: A systematic review of the literature was conducted to evaluate long-term patient survival in the instances of LT for pancreatic NET. Univariate and multivariate regression analyses and survival analysis were performed.
Results: Fifty-three clinical studies were screened. Data from 20 studies encompassing 89 transplanted patients were included in the study. Most primary tumors were endocrine pancreatic tumors (n=69), with gastrinomas representing the most frequent diagnosis (n=21). There were 61 functioning pancreatic NET. Simultaneous LT and pancreatic NET resections were performed in 45 instances. Cumulative 1-, 3-, and 5-year survival was 71%, 55%, and 44%, respectively, with a calculated mean survival of 54.45±6.31 months. Vasoactive intestinal peptide (VIPomas) had the best overall survival. Recurrence-free survival at 1, 3, and 5 years was 84%, 47%, and 47%, respectively. Recipient age more than or equal to 55 years (P=0.0242) and simultaneous LT-pancreatic resection (P=0.0132) were found to be significant predictors of worse survival by both univariate and multivariate Cox proportional hazard analyses. A scoring system was developed, with prognostic points assigned as follows: age more than or equal to 55 years:age less than 55 years=1:0 points and simultaneous LT-pancreatic resection:LT alone=1:0 points. This stratification delineated three separate population samples corresponding to patients with scores of 0, 1, and 2, respectively. The calculated 5-year survival for scores 0, 1, and 2 was 61%, 40%, and 0%, respectively (P=0.0023).
Conclusions: Despite the limitations of this retrospective analysis, good results can be achieved even for pancreatic NET primaries if the above-proposed scoring system is applied.