ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2019) 63 P443 | DOI: 10.1530/endoabs.63.P443

Type 1 gastric neuroendocrine tumor study in Hospital Clinico San Carlos (HCSC), Madrid

Elvira Ramos, Elvira Barrio, Ignacio Vargas-Zúñiga, Raquel Pallarés, Mario Pazos, Pablo Suárez, Paula Aldama, Concepción Sevilla, Paz De Miguel & Jose Ángel Díaz

Hospital Clínico San Carlos, Madrid, Spain.

Introduction: Type 1 Gastric neuroendocrine tumors account for 70 to 80 percent of all gastric neuroendocrine tumors (G-NETs) and they are found more commonly in older adults, particularly women. They are associated with autoimmune metaplastic atrophic gastritis (AMAG) with or without pernicious anemia. They are usually smaller than 1 cm and often multiple. Our goal is to describe different characteristics of type 1 G-NETs and to study possible prognostic factors related to the progression-free survival (PFS).

Material and methods: Descriptive, observational, retrospective and inferential study of 31 patients diagnosed with Type 1 G-NET and neuroendocrine cell micronodular hyperplasia, diagnosed and followed in the Endocrinology department of HCSC during the last 15 years. We define Progression-Free Survival (PFS) as the proportion of patients who remain without progression of the disease after a defined period of time. SPSS 23.0 was used for statistical analysis.

Results: The mean age at diagnosis was 57.97 (SD 13.19). 61% of the patients were female. 31.3% presented micronodular hyperplasia. 60.4% were grade 1 type 1 G-NET. 75.6% presented a single lesion. Median size was 0.4 cm (IQR 0.3–0.6). 41.9% of the lesions were located in the body of the stomach and 32.3% additionally in the fundus. Ki67 was ≤2% in 95.3% of the cases. Only 10.4% were treated with somatostatin analogues. Median serum chromogranin A was 7.35 nmol/l (IQR 4.56–10.0). As for survival analysis, 32.3% presented tumor progression or relapse. Median PFS was 5 years (CI 95% 1.805–8.195). Relapse was found to happen earlier in males (81% within the first year) than in females (41%) (Log Rank 1.485, Breslow 2.944). Median PFS was 5.00 years (CI 95% 1.611–8.389) in patients younger than 60, compared to 3.00 years (CI 95% 0.614–5.386) in those older than 60.

Conclusions: Our sample describes the general characteristics of population with Type 1 G-NET in terms of sex, age, location, size and others. Our study seems to demonstrate that these tumors have a higher chance of relapse in the short and medium term. Regarding survival analysis, we observed males and patients older than 60 present a shorter PFS, which might reflect the need for periodic gastroscopic check-ups more frequently in those groups of patients. Further prospective studies with a larger number of cases are needed in order to identify prognostic factors in the relapse of G-NETs in these patients.