Well-differentiated neuroendocrine tumors: a review covering basic principles to loco-regional and targeted therapies

Prognostic factors and treatment impact on overall survival in patients with renal neuroendocrine tumour

Background

Renal neuroendocrine neoplasms (R-NEN) are exceptionally rare tumours characterized by high mortality rates.

Objective

The objective of this study is to analyse prognostic factors and treatment impact on overall survival in patients with R-NEN.

Design setting and participants

We identified all patients with R-NEN in the National Cancer Database (NCDB) from 2004 to 2019 and identified prognostic factors for improved survival.

Results and limitations

Of 542 R-NEN cases, 166 (31%) were neuroendocrine tumour grade 1 (NET-G1), 14 (3%) were neuroendocrine tumour grade 2 (NET-G2), 169 (31%) were neuroendocrine carcinoma (NEC-NOS), 18 (3%) were large cell neuroendocrine carcinoma (LC-NEC) and 175 (32%) were small cell neuroendocrine carcinoma (SC-NEC). Median overall survival for all patients in the study was 44.88 months (SE, 4.265; 95% CI, 27.57-62.19). Median overall survival was 7.89 months (SE 0.67; 95% CI, 6.58-9.20) for patients without surgical intervention and 136.61 months (SE 16.44; 95% CI, 104.38-168.84, p < 0.001) for patients who underwent surgery. Increased age (HR, 1.05; 95% CI, 1.03-1.06; p < 0.001), T4 stage disease (HR, 3.17; 95% CI, 1.96-5.1; p < 0.001), NEC-NOS histology (HR, 2.82; 95% CI, 1.64-4.86; p < 0.001), LC-NEC histology (HR, 2.73; 95% CI, 1.04-7.17; p = 0.041) and SC-NEC histology (HR, 5.17; 95% CI, 2.95-9.05; p < 0.001) were all positive predictors of worsening overall survival. The main limitation of the study is its retrospective design.

Conclusion

R-NEN is an aggressive tumour characterized by high mortality rates. Surgery continues to be the mainstay of treatment and has shown to provide a survival benefit for most patients.

Patient Summary

R-NEN is composed of several tumour histologies that differ based on their aggressiveness with NEC-NOS and SC-NEC being the most lethal. Surgery, predominantly through minimally invasive approaches, is the mainstay of treatment and has a clear survival benefit.

Real world outcomes in patients with neuroendocrine tumor receiving peptide receptor radionucleotide therapy

Aim

¹⁷⁷Lu-Dotatate (Lu-177), a form of peptide receptor radionuclide therapy (PRRT), was approved by Food and Drug Administration (FDA) for the treatment of somatostatin-receptor-positive neuroendocrine tumors (NETs) in 2018. Clinical trials prior to the FDA approval of Lu-177 showed favorable outcomes but there is limited published real world outcomes data. This study aims to describe and analyze real world outcomes of patients with NET who received Lu-177.

Methods

After obtaining institutional review board approval, retrospective evaluation was performed to analyze the efficacy of Lu-177 for somatostatin receptor-positive gastro-entero-pancreatic NETs (GEP-NETs) patients at the University of Kansas Cancer Center between June 2018 and September 2021. This study aims to determine the response rate to the treatment of the entire cohort and subgroups.

Results

A total of 65 patients received Lu-177 of which 58 completed treatment. The 58 patients had a median age of 61.5 years, 24 females and 34 males, 86% Caucasian and 12% black. The origins of NETs were primarily small bowel (n = 24) and pancreatic (n = 14). Pathology showed grades 1 (n = 21), 2 (n = 25), and 3 (n = 4) and were primarily well-differentiated tumors (n = 4). Among the cohort, 52 patients had imaging to assess response with 14 (26.9%) patients with partial response (PR), 31 (59.6%) with stable disease (SD), and 7 (13.5%) with progressive disease (PD). In a subset analysis, patients with non-functional disease (n = 29) had higher rates of PR 42.3% (compared to 11.5%, P = 0.0147) and higher disease control rate of 96% (compared to 78%, P = 0.042) than patients with functional disease (n = 29). Patients with non-functional disease had a lower PD of 3.85% (compared to 23%, P = 0.0147) than those with functional disease.

Conclusions

This real world outcomes analysis of NETs treated with Lu-177 shows improved PR when compared to the initial clinical trials and is promising for patients. In addition, patients with non-functional tumors were found to have a statistically significant improved response rate which has not been described in the literature before. If these study findings are validated in a larger cohort they may guide patient selection for Lu-177 therapy in the future.

Level of plasma catecholamine predicts surgical outcomes of carotid body tumors: Retrospective cohort study

BACKGROUNDS

Carotid body tumors (CBTs) are rare neoplasms and some of them produce catecholamine. Although operations for catecholamine-producing CBTs are safe, the relationship between prognosis and endocrine function has not been analyzed before.

METHODS

Patients diagnosed with CBTs in our department between 2009 and 2018 were analyzed. Plasma catecholamine was examined as a variable of surgical outcomes and prognosis by using statistical methods.

RESULTS

Patients who suffered CBTs and underwent operations were divided into two groups according to their plasma catecholamine. Patients in the normal group had more or heavier surgical complications, such as neurological complications (P = .008) and blood loss (P = .03), than those in the high group. However, overall survival, local recurrence, and remote metastasis were not varied significantly in both groups.

CONCLUSIONS

A high level of plasma catecholamine was a predictor for the improved operative outcomes of CBTs. Hence, nonfunctional CBTs had further short-term surgical complications.

A case report on metastatic ileal neuroendocrine neoplasm to the breast masquerading as primary breast cancer: A diagnostic challenge and management dilemma

RATIONALE

Metastatic neuroendocrine neoplasms (NENs) to the breast are very rare entities comprising only 1% to 2% of all metastatic breast tumors. In this article, we describe a case of a neuroendocrine ileal neoplasm metastatic to breast and liver, with breast metastatic tumor to be the initial manifestation of the disease.

PATIENT CONCERNS

We herein report a rare case of a female patient admitted to our department with a palpable painful mass on her left breast.

DIAGNOSIS

The surgical and histological investigation revealed a metastatic neuroendocrine neoplasm to the breast originated from terminal ileum.

INTERVENTIONS

A left lumpectomy, right hemicolectomy, cholecystectomy, left hepatectomy along with liver metastasectomies (V, VI, VIII) plus radiofrequency ablation of lesions to the right liver lobe plus standard lymphadenectomy was performed.

OUTCOMES

Considering the advanced stage of the disease, the patient received an adjuvant therapy of somatostatin analog plus everolimus. Under the guidance of oncological consultation, patients follow-up with CT and MRI scan and clinical re-evaluations in the first 3 and 6 months, substantiates no evidence of recurrence and she presents herself asymptomatic.

LESSONS

An appropriate level of suspicion and selective immunohistochemistry in these cases, particularly where no prior history of a known primary neuroendocrine neoplasm occurs, may help to diagnose a previously undetected neuroendocrine tumor elsewhere in the body and provide guidance for the appropriate treatment selection.

Elevated Alkaline Phosphatase Prior to Transarterial Chemoembolization for Neuroendocrine Tumors Predicts Worse Outcomes

INTRODUCTION

We hypothesized that an elevated preoperative alkaline phosphatase (AP) predicted worse outcomes for patients undergoing transarterial chemoembolization (TACE) for neuroendocrine tumor (NET) liver metastases.

METHODS

We reviewed all patients who underwent TACE for metastatic NET between 2009 and 2013. Survival was evaluated using preprocedure variables.

RESULTS

One hundred and nine patients underwent 210 TACE procedures. The average age was 57.7 years (range 20-78). Primary sites included pancreas (N = 20), other gastrointestinal (N = 52), lung (N = 9), and unknown (N = 28). The tumor was grade 1 in 68 (62 %), grade 2 in 21 (19 %), and grade 3 in 3 (3 %). Extrahepatic disease was present in 54 (50 %) and greater than 50 % hepatic tumor burden by imaging in 63 (58 %). Elevated bilirubin occurred in 8 (7 %), elevated AP in 22 (20 %), elevated ALT in 21 (19 %), and elevated AST in 41 (38 %). Univariate predictors included tumor grade (43 vs 27 vs 21 months, p = 0.015), hepatic tumor burden (59 vs 37 months, p = 0.009), and elevated AP (59 vs 23 months, p < 0.001). On multivariate analysis, only elevated AP (p = 0.001) predicted worse survival.

CONCLUSIONS

Elevated AP prior to TACE for metastatic NET portends a worse survival outcome, even more so than tumor grade or extent of hepatic disease.

Putting the pieces together: necrolytic migratory erythema and the glucagonoma syndrome

Glucagonomas are slow-growing, rare pancreatic neuroendocrine tumors. They may present with paraneoplastic phenomena known together as the "glucagonoma syndrome." A hallmark sign of this syndrome is a rash known as necrolytic migratory erythema (NME). In this paper, the authors describe a patient with NME and other features of the glucagonoma syndrome. The diagnosis of this rare tumor requires an elevated serum glucagon level and imaging confirming a pancreatic tumor. Surgical and medical treatment options are reviewed. When detected early, a glucagonoma is surgically curable. It is therefore imperative that clinicians recognize the glucagonoma syndrome in order to make an accurate diagnosis and refer for treatment.

Neuroendocrine neoplasms of the gut and pancreas: new insights

Neuroendocrine neoplasms arise in almost every organ of the body and are variably defined according to the site of origin. This Review focuses on neuroendocrine neoplasms of the digestive tract and pancreas. The 2010 WHO classification of tumors of the digestive system introduces grading and staging tools for neuroendocrine neoplasms. A carcinoid is now defined as a grade 1 or 2 neuroendocrine tumor and grade 3, small-cell or large-cell carcinomas are defined as neuroendocrine carcinoma. Epidemiological data show a worldwide increase in the prevalence and incidence of gastroentero-pancreatic neuroendocrine tumors in the past few decades, which is probably due to improved methods of detection of these tumors. The current diagnostic procedures and treatment options for neuroendocrine neoplasms are defined and summarized in the Review, although evidence-based data are lacking. Surgery remains the treatment mainstay and somatostatin analogues the basis for both diagnosis and therapy as the only 'theranostic' tool. Emerging compounds including chemotherapeutic agents, small molecules and biological therapies may provide new hope for patients.