Introduction.

Neuroendocrine tumors of the appendix (NET-A) correspond to the most common appendicular neoplasia. Although they usually have a benign behavior, their potential for regional extension and metastasis makes it necessary to accurately determine the prognosis of each patient. The objective of the present study was to design and validate a prognostic nomogram to predict survival of patients with NET-A.

Methods.

Retrospective cohort study, based on information from the surveillance, epidemiology, and outcomes database of the National Cancer Institute of the United States of America. Patients diagnosed with NET-A between 1978 and 2016 were included. Survival analysis was performed using a Cox regression model. With these results, nomograms for general and cancer-specific survival at one, two, three and five years were constructed. The analyzes were carried out in the statistical software R (v. 3.5.3).

Results.

3585 patients with a NET-A diagnosis were included, 55.8% were women, and the median age was 49 years. The most frequent histological subtype was the Mixed Histology Tumor (MHT). Age, histological subtype, size and tumor extension were the only variables independently associated with survival after multivariate analysis. The validated nomogram presented an outstanding discrimination capacity to predict both overall survival 0.81 (95% CI: 0.76-0.86) and cancer specific survival 0.88 (95% CI: 0.83 to 0.92).

Discussion.

The present study proposes a prognostic survival nomogram for patients with NET-A, taking into account the histological subtype, and achieves an outstanding discrimination capacity for the prediction of these outcomes. We highlight the poorer prognosis of patients with MHT, in addition to the similar survival between patients undergoing hemicolectomy and those undergoing appendectomy or resection of the cecum, after multivariate analysis. It is necessary to evaluate the role of adjuvant therapeutic modalities in the survival of these patients.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )