Influence of Gender on Therapy and Outcome of Neuroendocrine Tumors of Gastroenteropancreatic Origin: A Single-Center Analysis

Abstract

Introduction: Gender-specific treatment is gaining growing attention in various fields of medicine. In gastrointestinal cancer, influence of sex on outcome has been discussed, while this has not been the case in neuroendocrine tumors. Overall, the incidence of neuroendocrine neoplasms is rising, especially for appendiceal neuroendocrine neoplasms in women. Also, women seem to have a slight advantage in response to therapy, especially for liver metastases.

Objectives: This single-center analysis aimed to investigate gender-specific differences in our cohort related to distribution, therapy, and outcome.

Methods: Patients from the NET registry as well as the clinic database were evaluated retrospectively concerning overall survival and response to therapy with respect to gender. A subgroup analysis was carried out for patients with low grading and response to chemotherapy, as well as for patients with good and moderate grading receiving peptide receptor radionuclide therapy and for a group of patients with liver surgery.

Results: No specific differences could be detected for overall survival or response to therapy between male and female patients. Mean survival was estimated with 242.2 months (±10.39 SD) altogether and 221.7 months (± 13.02 SD) for male patients and 253.5 months (±15.24 SD) for female patients from the NET registry from initial diagnosis. There was no significant difference between female and male patients (p = 0.136). For patients receiving chemotherapy, overall survival from initial diagnosis was calculated with 26 months (±2.59) and did not show any significant differences between female and male patients 24.8 months (±2.81 SD) vs. 27.8 months (±3.86 SD, p = 0.87). Patients undergoing peptide receptor radionuclide therapy showed a median progression-free survival of 26.9 months (±2.82 SD), with 16.9 (±5.595 SD) and 26.9 months (±3.019 SD) for male and female patients, respectively (p = 0.2). In the group of patients with liver surgery, female patients reached an estimated overall survival of 64.7 months (±4.16 SD), male patients 65.1 months (±2.79 SD, p = 0.562).

Conclusion: Our cohort did not reveal significant differences in outcome and response to therapy with regards to gender.

Keywords: Chemotherapy; Gender medicine; Liver metastases; Neuroendocrine neoplasm; Radiotherapy.

Fig. 1

Kaplan-Meier curve displaying overall survival after diagnosis for female (green) and male (blue) patients with neuroendocrine neoplasias independent of therapeutic strategy.

Fig. 2

Illustration of individually highest recorded Ki67 value in percentiles and distribution between female (green) and male (blue) patients for patients receiving chemotherapy.

Fig. 3

Kaplan-Meier curve displaying progression-free survival (PFS) of female (green) and male (blue) patients with NEC, NET G3, or MiNEN G3 receiving chemotherapy. Log-rank test.

Fig. 4

Kaplan-Meier curve displaying overall survival of female (green) and male (blue) patients with NEC, NET G3, or MiNEN G3 receiving chemotherapy. Log-rank test.

Fig. 5

Kaplan-Meier curve displaying survival since start of chemotherapy of female (green) and male (blue) patients with NEC, NET G3, or MiNEN G3 receiving chemotherapy. Log-rank test.

Fig. 6

Kaplan-Meier curve showing progression-free survival after first cycle of Lu-177-DOTATOC-PRRT for male (blue) and female (green) patients with gastroenteropancreatic NEN G1/G2.

Fig. 7

Kaplan-Meier curve displaying overall survival after diagnosis for male (blue) and female (green) patients undergoing hepatic resection for metastatic neuroendocrine neoplasms.

Fig. 8

Kaplan-Meier curve displaying survival after liver surgery for hepatic metastases in male (blue) and female (green) patients with neuroendocrine neoplasms.