DIVERSE CLINICAL AND PATHOLOGICAL FEATURES OF GASTRIC CARCINOID AND THE RELEVANCE OF HYPERGASTRINEMIA

The etiology, prognosis, and optimal management of primary gastric carcinoids remain controversial. Records of 36 consecutive patients with gastric carcinoid (15 men) were reviewed retrospectively between 1975 and 1990. Follow-up was complete in 97% of cases. Mean age at diagnosis was 58.4 years (range 24-82 years). The clinical presentations included anemia (72%), pain (69%), and carcinoid syndrome (11%). Associated autoimmune and endocrine abnormalities were common and included atrophic gastritis (67%), pernicious anemia (58%), hypothyroidism (39%), diabetes (19%), Addison's disease (6%), and hyperparathyroidism (6%). Lesions were nonantral in 78%, involving only the corpus in 42%, the fundus in 28%, and only the antrum in 8%; 42% were multiple. Urinary 5-hydroxyindoleacetic acid (5-HIAA) and serum gastrin levels were elevated in 17% and 50% of those tested, respectively. Histologic examination revealed that 28% of lesions were greater than or equal to 2 cm, and 33% had liver metastases on presentation or developed them during follow-up. Eight patients (22%) died of tumor with a median survival of 39 months. The presence of metastases, atypical histology, serosal involvement, and size > 2 cm were adverse prognostic factors. In patients without hypergastrinemia (n = 6), 66% developed metastases, 60% had elevated 5-HIAA, and 50% died of carcinoid tumor. In sharp contrast, those patients with hypergastrinemia and ''typical'' gastric carcinoids (n = 15), metastases and death did not occur (p < 0.003 and p < 0.005, respectively, compared with eugastrinemic patients). In the latter group (hypergastrinemia and typical histology), pernicious anemia was common (73%); solitary lesions and serosal penetration were seen comparatively less often (33% versus 100%, p < 0.005 and 0% versus 33%, p < 0.05), respectively); and no lesion measured > 2.0 cm compared to 66% in the group without elevated gastrin (p < 0.002). No patient with hypergastrinaemia had elevated levels of 5-HIAA. Overall survival at 5 and 10 years was 58% and 28%, respectively. Survival was 80% at 5 and 10 years in the hypergastrinemic group. Gastric carcinoid tumors that are histologically atypical, large (> 2 cm), or present without elevated gastrin are potentially lethal and require aggressive therapy. In contrast, gastric carcinoids with typical histology and hypergastrinemia are rarely lethal, and conservative management with local excision and close observation is appropriate.