Survival and Clinical Outcome of Patients with Neuroendocrine Tumors of the Gastroenteropancreatic Tract in a German Referral Center

Abstract

Neuroendocrine tumors (NETs) are rare neoplasms. Approximately 75% of all cases manifest in the gastroenteropancreatic (GEP) system. Because of the low incidence of NETs, limited data about the clinical outcome and prognostic variables are available. In an attempt to identify prognostic parameters, we investigated the distribution of primary tumors, pattern of metastasis formation, clinical presentation, histological classification, and outcome of therapeutic interventions in a large patient cohort cared for in a German referral center. In 254 patients with GEP-NETs, the primary tumor was of foregut, midgut, or hindgut origin in 44.1% (28.7% pancreas), 43.7% (34.7% jejunoileum), and 4.3%, respectively. No primary tumor was found in 7.9%. Metastases occurred preferentially in lymph nodes and the liver. The overall 5-year survival rate was 57.1%. In the absence or presence of metastases at initial diagnosis the 5-year survival rate was 80.0% and 51.7%, respectively. The 5-year survival rate was related to the localization of the primary and was 75.0% and 42.9% for jejunoileal and pancreatic tumors, respectively. The size of the primary tumor (<2 cm) and histological grading as low-grade malignant were both associated with a significantly longer survival. Surgery with curative intent was attempted in 141 patients. However, an R(0) resection was achieved in only 66.0% of these patients. Five-year survival rate in the latter group was significantly higher (77.3%) as compared with all surgical patients (55.4%). Long-term tumor-free survival was obtained in only 53.7% of successfully resected patients. Palliative medical treatment, either with chemotherapy (i.e., especially for foregut NETs) or biotherapy (especially for midgut NETs), was only moderately effective for both therapeutic regimens.

Epidemiological trends of pancreatic and gastrointestinal neuroendocrine tumors in Japan: a nationwide survey analysis

“…The incidences of new-onset PNETs in 2005 and 2010 were about 1.01 and 1.27 per 100,000 people, respectively, indicating a 5-year increase in the incidence of new-onset PNETs. Interestingly, the percentage of NFPNETs increased from 42.8 % in 2005 to 65.5 % in 2010, approaching that of Western nations [2,7,8]. There are 2 possible reasons for this.…”

Diagnosis and Treatment of Gastroenteropancreatic Neuroendocrine Tumors: Current Data on a Prospectively Collected, Retrospectively Analyzed Clinical Multicenter Investigation

“…However, the absence of documented functionality does not exclude a hormonally active syndrome in many patients. On reviewing single-center reports from referral centers [13] and recently established national registries [14,15], functioning tumors were reported in up to 40% of patients. Up to 49% localized in the small intestine [14,16,17] and up to 75% localized in the pancreas [9,18] were functioning.…”

PAX8 expression reliably distinguishes pancreatic well-differentiated neuroendocrine tumors from ileal and pulmonary well-differentiated neuroendocrine tumors and pancreatic acinar cell carcinoma

“…Of the gastroenteropancreatic neuroendocrine tumors, tumors of the pancreas and ileocecum most often give rise to metastatic disease at the time of initial presentation. 2,29 Pape et al 29 found that 53% of pancreatic and 70% of ileal neuroendocrine tumors demonstrated metastatic disease at initial presentation compared with a o10% rate of metastatic disease at presentation for rectal, duodenal, appendiceal, and gastric neuroendocrine tumors. Similarly, Modlin et al 2 found that 58% of small intestinal and 72% of pancreatic neuroendocrine tumors had non-localized disease at presentation, compared with much lower rate of non-localized disease for other gastrointestinal sites.…”