Place of surgical resection in the treatment strategy of gastrointestinal neuroendocrine tumors

The Clinicopathological Characteristics and Surgical Treatment of Gastrointestinal Neuroendocrine Neoplasm-A 10-Year Single-Center Experience

Background: Gastrointestinal neuroendocrine neoplasms (GI-NENs) represent a diverse group of tumors, with surgical resection being the gold standard for treatment. Materials and Methods: A retrospective analysis was conducted on 63 patients (32 women, 31 men) who underwent surgery for GI-NENs at the Department of Digestive Tract Surgery from January 2013 to June 2023. Tumors were classified by stage (localized, regionally advanced, metastatic). Results: Clinical symptoms were reported by 42 (66.7%) patients, with abdominal pain being the most common symptom, affecting 28 (44.4%) patients. The majority of tumors (44, 69.8%) originated in the midgut. The most frequently performed surgery was right hemicolectomy, carried out on 33 (52.4%) patients. Radical tumor resection was performed in 35 (55.6%) patients. Postoperative complications occurred in 12 (19%) patients, with male gender identified as an independent predictive factor for complications (p = 0.04). Non-functioning tumors were more common (33, 52.4%), and most tumors were classified as grade 1 histopathologically (49, 77.8%). Distant metastases were present in 29 (46%) patients. The overall two-year survival rate was 94.9%, with a five-year survival rate also estimated at 94.9%. Conclusions: GI-NENs are often diagnosed at advanced stages, frequently with distant or lymph node metastases, and predominantly arise in the midgut. Despite low postoperative morbidity and mortality, male gender may be a predictor of postoperative complications. Overall, the prognosis for GI-NENs is favorable, reflected in high overall survival rates.

Management of Primary Hepatopancreatobiliary and Ampulla Large Cell Neuroendocrine Carcinoma

Background: Large cell neuroendocrine carcinoma (LCNEC) of the liver, gallbladder, pancreas, and ampulla is rare and usually arises in case reports, and thus to date, no studies have well described the treatment options and outcomes of those patients. Methods: The data of 108 patients diagnosed as hepatopancreatobiliary and ampulla LCNEC between 2004 and 2015 were retrieved from the surveillance, epidemiology, and final results. Results: In the entire cohort, the median overall survival (OS) was 10 months. For nonmetastatic patients, the median OS was 32 months for surgery of the primary tumor alone (n = 17), 19 months for surgery of the primary tumor and adjuvant therapy (n = 19), and 1 month for nonsurgical treatment (n = 8). For metastatic patients, the median OS was 14 months for patients who received surgery of the primary tumor with and without adjuvant therapy (n = 16), 9 months for patients undergoing adjuvant treatment alone (n = 30), and 1 month for patients who had no treatment (n = 16). Multivariate analysis revealed that surgery of the primary tumor was an independent factor for improved survival. Conclusions: This disease offers a very poor prognosis despite aggressive treatment. Radical resection is the first choice for resectable tumors, whereas surgical resection of the primary tumor plus adjuvant therapy might represent a valid option for metastatic disease. However, further studies are needed to confirm this.

Management of Locally Advanced and Unresectable Small Bowel Neuroendocrine Tumours

Three subtypes of small bowel neuroendocrine tumours (SBNETs) have been described: Type A: SBNET with resectable mesenteric disease that does not involve the mesenteric root; Type B: "Borderline resectable" SBNET presenting with mesenteric nodal metastases and fibrosis adjacent but not encasing the main trunk of the superior mesenteric artery (SMA) and superior mesenteric vein (SMV); and Type C: "Locally advanced or irresectable" SBNET where tumour deposits and fibrosis encase the SMA and SMV. Type C SBNETs are rare and constitute around 5% of patients in reported series, although this may underestimate the prevalence. In these patients, almost all will present with symptoms of intestinal ischemia or obstruction and symptom management should be a primary main focus of treatment. All patients should be carefully staged with cross-sectional imaging and 68 Ga-dotate positron emission tomography, and discussed at a dedicated neuroendocrine tumour multidisciplinary meeting. Expert surgical review should always be sought as experienced centers have a high rate of successful resection of primary tumours and mesenteric disease. If resection is not feasible, surgical bypass should be considered in patients with a discrete and symptomatic point of obstruction. Non-operative management should emphasize symptomatic treatment with somatostatin analogs, nutritional advice and support and palliative care. Successful neoadjuvant approaches utilizing peptide radionucleide receptor therapy and systemic chemotherapy with everolimus or temazolamide/capecitabine have not been reported.

A Modified Duodenal Neuroendocrine Tumor Staging Schema Better Defines the Risk of Lymph Node Metastasis and Disease-free Survival

Duodenal neuroendocrine tumors are rare but increasing in incidence and optimal management is hindered by lack of duodenum-specific staging. Duodenal carcinoids were identified in the Surveillance, Epidemiology and End Results tumor registry. Depth of invasion was defined as limited to lamina propria (LP), invading muscularis propria (MP), through muscularis propria (TMP), and through serosa (S). Nine hundred forty-nine patients were identified with majorities being male (57%), white (70%), and node-negative (87%). Tumor size (cm) was less than 1, 47 per cent; 1 to 2, 35 per cent; and greater than 2, 8 per cent with 76 per cent LP. Lymph node (LN) involvement was associated with age, depth of invasion (LP 4%, MP 28%, TMP 54%, and S 57%) and size (less than 1 cm, 3%; 1 to 2 cm, 13%; and greater than 2 cm, 40%). Using the current T staging, LN involvement was: T1 (LP) 2 per cent, T2 (MP or greater than 1 cm) 13 per cent, T3 (TMP) 54 per cent, and T4 (S) 57 per cent. We reclassified current T1 to T1a and current T2 stage to T1b (1 to 2 cm and LP) and T2 (MP or greater than 2 cm). LN metastasis for T1b tumors was 4.7 per cent compared with 20.8 per cent for T2. The resulting TNM classification better defines 5-year disease-specific survival. Our modified staging schema identifies a low-risk group (T1a and T1b) that may be considered for local therapy.

Primary extrahepatic bile duct neuroendocrine tumor with obstructive jaundice masquerading as a Klatskin tumor

Neuroendocrine tumors (NETs) of the extrahepatic bile duct are extremely rare and reported infrequently in the literature. These tumors are difficult to diagnose preoperatively, and the prognosis is variable, often determined by extent of disease, tumor grade and resectability. This case report presents a 45-year-old male with history of biliary obstruction relieved by endobiliary stents with common hepatic duct stricture just above the cystic duct, thought to be a Klatskin’s cholangiocarcinoma. Final pathological examination was consistent with primary extrahepatic NET.

Retrospective analysis of the clinicopathological characteristics of gastrointestinal neuroendocrine neoplasms

The aim of the present study was to analyze and summarize the clinicopathological characteristics and factors affecting prognosis for patients with gastrointestinal neuroendocrine neoplasms (GINENs). Retrospective analysis was conducted on the clinicopathological data of 74 patients who were diagnosed with GINEN, and immunohistochemical methods were used to detect the expression levels of relevant markers [synaptophysin (Syn), chromogranin A (CgA) and Ki-67]. Among the 74 cases with GINEN, there were 39 males and 35 females, with an average age of 56.9 years. There were 32 neoplasms in the rectum, 29 in the stomach, 6 in the colon, 2 in the small intestine and 5 in the appendix. All 74 cases underwent surgical resection. According to the World Health Organization Classification of Tumors of the Digestive System (2010), the diagnosis of the 74 cases showed 41 cases (55.4%) of neuroendocrine tumor (NET; 25 cases of G1 and 16 cases of G2), 21 cases (28.4%) of neuroendocrine carcinoma (NEC) and 12 cases (16.2%) of mixed adenoneuroendocrine carcinoma (MANEC). Additionally, 19 cases had metastasis to lymph nodes. During 10-34 months of follow-up, 15 patients had distant metastasis and 24 patients succumbed, and the accumulative survival rate in 1 or 2 years was 87.8 and 74.3%, respectively. Six factors, namely neoplasm size, depth of invasion, lymph node metastasis, distant metastasis, pathological type and the expression or lack of expression of CgA, significantly affected the survival time of patients. Definitive diagnosis of GINEN mainly relies on pathological diagnosis. GINENs with different histopathological types and grading have different clinicopathological characteristics and prognosis: NETs are mainly early lesions with a good prognosis, whereas NECs and MANECs have high malignancy and strong invasion with a worse prognosis.

Neuroendocrine Carcinomas of the Gastroenteropancreatic System: A Comprehensive Review

To date, empirical literature has generally been considered lacking in relation to neuroendocrine carcinomas (NECs), the highly malignant subgroup of neuroendocrine neoplasms. NECs are often found in the lungs or the gastroenteropancreatic (GEP) system and can be of small or large cell type. Concentrating on GEP-NECs, we can conclude that survival times are poor, with a median of only 4–16 months depending on disease stage and primary site. Further, this aggressive disease appears to be on the rise, with incidence numbers increasing while survival times are stagnant. Treatment strategies concerning surgery are often undecided and second-line chemotherapy is not yet established. After an analysis of over 2600 articles, we can conclude that there is indeed more empirical literature concerning GEP-NECs available than previously assumed. This unique review is based on 333 selected articles and contains detailed information concerning all aspects of GEP-NECs. Namely, the classification, histology, genetic abnormalities, epidemiology, origin, biochemistry, imaging, treatment and survival of GEP-NECs are described. Also, organ-specific summaries with more detail in relation to disease presentation, diagnosis, treatment and survival are presented. Finally, key points are discussed with directions for future research priorities.