Mixed adenoneuroendocrine carcinoma (MANEC) of the lower gastrointestinal tract: A systematic review with Bayesian hierarchical survival analysis

Combining anti-PD-1 antibodies with surufatinib for gastrointestinal neuroendocrine carcinoma: Two cases report and review of literature

BACKGROUND

Gastrointestinal neuroendocrine carcinoma (GI NEC) has a low incidence rate and poor prognosis. Most patients already have metastatic disease when they are diagnosed. Platinum chemotherapy is the main means of treating metastatic GI NECs. There is a lack of effective treatment methods after chemotherapy failure. Therefore, Therefore, selecting appropriate posterior-line treatment programs to improve the prognosis of patients is urgently needed.

CASE SUMMARY

A 64-year-old female was diagnosed with stage IV NEC of the rectum due to abdominal pain and rectal bleeding. After multiline chemotherapy, the condition progressed, and the patient was treated with a combination of camrelizumab and surufatinib. The efficacy evaluation revealed partial remission (PR) and stable conditions, with the expression of the tumor marker neuron-specific enolase (NSE) returning to normal. The adverse reactions were controllable, and the overall condition was good, with weight gain achieved in the past four years. Another 51-year-old female experienced recurrence and metastasis of a duodenal NEC after surgery. After multiline chemotherapy, she received sintilimab combined with surufatinib. The curative effect fluctuated between PR and stability. During treatment, she recovered from immune-related diabetes and later died due to deterioration of her condition. During the treatment, the patient's NSE level returned to normal.

CONCLUSION

The combination of antiangiogenic targeted drugs and immunotherapy provides a new therapeutic approach for the treatment of metastatic GI-NECs.

Risk of lymph node metastases and conditional survival in appendiceal neuroendocrine neoplasms

BACKGROUND

National Comprehensive Cancer Network guidelines recommend segmental colectomy for appendiceal neuroendocrine neoplasms >2.0 cm given the risk for lymph node involvement. However, additional clinicopathologic factors are associated with nodal metastases, and thus survival. Given dynamic changes of prognosis over time, conditional overall survival, the probability of surviving after a specific interval, has emerged as a novel oncologic outcome, but is scarcely available for appendiceal neuroendocrine neoplasms.

METHODS

Adults with stage I-III appendiceal neuroendocrine neoplasms who underwent colectomy from 2010-2017 were identified in the National Cancer Database. Tumor histologies included neuroendocrine tumor grade 1, neuroendocrine tumor grades 2 and 3, neuroendocrine carcinoma, mixed neuroendocrine non-neuroendocrine neoplasm, and goblet cell carcinoma.

RESULTS

Of 3,541 patients (median age 51 years, 43% male, 88% White), 16% had positive lymph nodes. Overall, 40% had neuroendocrine tumor grade 1, 4% neuroendocrine tumor grades 2 and 3, 10% neuroendocrine carcinoma, 12% mixed neuroendocrine non-neuroendocrine neoplasm, and 30% goblet cell carcinoma. Increasing depth of invasion, lymphovascular invasion, and increasing size were associated with lymph node metastases. Eighty-seven percent were alive at 2 years. Mortality after 2 years was associated with older age, mixed neuroendocrine non-neuroendocrine neoplasm and goblet cell carcinoma histology, penetration through serosa, nodal involvement, and tumor size.

CONCLUSIONS

In a national cohort, 1 in 6 patients had positive lymph nodes, which was associated with depth of invasion, lymphovascular invasion, and size. These findings indicate additional factors should be considered when determining the extent of surgical resection and surveillance to improve survival outcomes. Additionally, patients with penetration through serosa, and mixed neuroendocrine non-neuroendocrine neoplasm or goblet cell carcinoma histology had worse conditional overall survival, potentially reflecting more aggressive tumor biology that warrants closer follow-up.

Mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) of the rectum

A 75-year-old man presented to our hospital complaining of abdominal distention. He underwent lower gastrointestinal endoscopic examination, which indicated a raised tumor of 20 mm in diameter in the sigmoid colon transition region of the rectum. Endoscopic mucosal resection was performed with the aims of treatment and diagnosis. Histopathological examination revealed a moderately differentiated adenocarcinoma with neuroendocrine carcinoma, which was classified as a mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN). The tumor had highly invaded the submucosa and positive vertical margins. Computed tomography showed no obvious lymph node metastasis or distant metastasis, so the patient underwent high-level anterior resection of the remaining lesion. The final diagnosis was MiNEN, pT3(SS), INFb, Ly1c, V0, Pn1a, pPM0, pDM0, pRM0, pN1a, and pStage IIIb (TNM Classification of Malignant Tumors, 8th Edition). The patient is recurrence free at 3 years without postoperative adjuvant therapy. We report this case with a review of the literature.

Mixed neuroendocrine-non-neuroendocrine neoplasm of the colon treated with laparoscopic resection and adjuvant chemotherapy: a case report

Mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) of the colon is rare with a poor prognosis. Since the first description of a mixed neoplasm 100 years ago, the nomenclature has evolved, most recently with the 2022 World Health Organization (WHO) classification system. We describe our experience of a case of locoregionally advanced MiNEN of the descending colon treated with curative laparoscopic resection and adjuvant chemotherapy. The patient is a 72 year old woman who presented with haematochezia. Initial clinical diagnosis was poorly differentiated adenocarcinoma of the descending colon, cT2N0M0, cStage I. Laparoscopic partial colectomy of the descending colon with D3 lymph node dissection and intracorporeal overlap anastomosis was performed. The pathological diagnosis however, returned mixed adenocarcinoma-neuroendocrine carcinoma (MANEC) of the descending colon, pT4aN1bM0, pStage IIIB, a subgroup of MiNEN: 70% was neuroendocrine carcinoma (NEC), whilst poorly differentiated mucinous carcinoma constituted 30% of the tumour. She completed 4 courses of irinotecan plus cisplatin (IP) adjuvant chemotherapy and is currently recurrence-free at postoperative year 2. The clinical course of MiNEN depends on the biology of the two components, both of which must be pathologically characterised. Even quantitatively discrete components should be carefully subtyped as their prognostic relevance is undetermined.

Mixed adenoneuroendocrine carcinomas of the appendix: Is there a survival advantage to right hemicolectomy over appendectomy?

BACKGROUND

the surgical treatment and prognostic characteristics of mixed adenoneuroendocrine carcinomas (MANEC) of the appendix are not yet available. In this study, we sought to figure out the choice of surgical approach (right hemicolectomy versus appendectomy), and explore the effect of chemotherapy on appendiceal MANEC.

METHODS

patients with appendiceal MANEC from the Surveillance, Epidemiology, and End Results database (2000-2020) were stratified by gender, race, age group, tumor grade, and TNM stage. Logistic regression and Kaplan-Meier analyses relating TNM stage, grade, and receipt of right hemicolectomy (abbreviated as colectomy) to overall and cancer-specific survival were performed.

RESULTS

455 patients with appendiceal MANEC were included, of whom 146(32 %) underwent appendectomy and 309(68 %) underwent colectomy. Patients who underwent colectomy had better cancer-specific survival (HR = 0.68, 95%CI (0.47-0.98), P = 0.041) and overall survival (HR = 0.67, 95%CI (0.48-0.93), P = 0.015) than those who underwent appendectomy alone. However, colectomy did not confer any survival advantage over appendectomy in subgroup analyses, including low-grade or high-grade tumors, T1-2N0M0 group, T3-4N0M0 group, node-positive non-metastatic tumors, and metastatic tumors. On multivariate analysis, lack of chemotherapy and high-stage (node-positive or metastatic) were associated with poorer overall survival; high-grade (grade 3-4) and high-stage were primary predictors of cancer-specific mortality. Furthermore, there was no significant association between colectomy and better survival, either overall survival or cancer specific survival, when accounting for tumor stage and grade.

CONCLUSIONS

Our study found that colectomy did not provide a survival benefit compared to appendectomy alone. Moreover, tumor stage and grade were independent determinants of cancer specific survival; chemotherapy and tumor stage were independent determinants of overall survival.

Preoperative Diagnostic Dilemma in Rapidly Progressive Mixed Neuroendocrine-Nonendocrine Neoplasm of the Ascending Colon: A Case Report

Introduction: Mixed neuroendocrine-nonendocrine neoplasms (MiNENs) of the digestive tract are rare. They contain both neuroendocrine and nonendocrine components. We here report a rare case of a metastatic MiNEN originating in the ascending colon. Case Presentation: An 80-year-old man presented with abdominal pain and vomiting. Colonoscopy showed an obstructing mass in the ascending colon, and a biopsy resulted in diagnosis of an adenocarcinoma. A CT scan revealed multiple liver metastases. Thus, our diagnosis was stage IV colon adenocarcinoma (cT4aN1bM1a according to TNM Classification of Malignant Tumors). The primary lesion was resected to alleviate symptoms. Histopathological and immunohistochemical examination revealed a well-differentiated adenocarcinoma and a small-cell neuroendocrine carcinoma, leading to the diagnosis of a MiNEN. The patient declined postoperative treatment and died approximately 2 months after the surgery. Conclusion: The incidence of MiNENs may be underestimated because they lack typical symptoms or imaging features and are therefore often only diagnosed after resection. Awareness of colonic MiNENs and further accumulation of cases are necessary to improve the outcomes.

Mixed neuroendocrine and adenocarcinoma of gastrointestinal tract: A complex diagnosis and therapeutic challenge

In this editorial we comment on the manuscript describing a case of adenocarcinoma mixed with a neuroendocrine carcinoma of the gastroesophageal junction. Mixed neuroendocrine and non-neuroendocrine neoplasms of the gastrointestinal system are rare heterogeneous group of tumors characterized by a high malignant potential, rapid growth, and poor prognosis. Due to the rarity of these cancers, the standard therapy is poorly defined. The diagnosis of these tumors is based on combination of morphological features, immunohistochemical and neuroendocrine and epithelial cell markers. Both endocrine and epithelial cell components can act independently of each other and thus, careful grading of each component separately is required. These cancers are aggressive in nature and the potential of each component has paramount importance in the choice of treatment and response. Regardless of the organ of origin, these tumors portend poor prognosis with increased proportion of neuroendocrine component. Multidisciplinary services and strategies are required for the management of these mixed malignancies to provide the best oncological outcomes. The etiopathogenesis of these mixed tumors remains obscure but poses interesting question. We briefly discuss a few salient points in this editorial.

Mixed neuroendocrine non-neuroendocrine neoplasms in gastroenteropancreatic tract

Mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs) are a heterogeneous group of malignant neoplasms that can settle in the gastroenteropancreatic tract. They are composed of a neuroendocrine (NE) and a non-NE component in at least 30% of each tumour. The non-NE component can include different histological combinations of glandular, squamous, mucinous and sarcomatoid phenotypes, and one or both of the components can be low-or high grade malignant. Recent changes in the nomenclature of these neoplasms might lead to great deal of confusion, and the lack of specific clinical trials is the main reason why their management is difficult. The review aims to clarify the definition of MiNEN and analyze available evidence about their diagnosis and treatment options according to their location and extension through careful analysis of the available data. It would be important to reach a general consensus on their diagnosis in order to construct a classification that remains stable over time and facilitates the design of clinical trials that, due to their low incidence, will require long recruitment periods.

Mixed adenoneuroendocrine carcinoma originating from the appendix and colorectum: a comparative analysis of a large population-based database

PURPOSE

As a rare gastrointestinal neoplasm, the demographic, clinicopathological, and prognostic characteristics of mixed adenoneuroendocrine carcinoma (MANEC) remain unclear. The purpose of this study was to evaluate its biological features, survival outcome, and prognostic factors.

METHODS

From the Surveillance, Epidemiology, and End Results (SEER) database, we retrospectively reviewed clinicopathological and survival data of 513 patients who were histopathologically diagnosed with MANEC of the appendix and colorectum bettween 2004 and 2015. The clinicopathological features and survival outcomes of MANEC located at different anatomical locations were compared, and predictive factors for cancer-specific survival (CSS) and overall survival (OS) were assessed.

RESULTS

In terms of anatomical distribution of MANEC, the appendix (64.5%, 331/513) was more frequently involved, followed by colon (28.1%, 144/513) and rectum (7.4%, 38/513). The MANEC at different anatomical locations had a distinct clinicopathological characteristic, and colorectal MANEC was significantly associated with more aggressive biological features. The survival outcomes of appendiceal MANEC were significantly better than that of colorectal MANEC (3-year CSS rate 73.8% vs 59.4%, P = 0.010; 3-year OS 69.2% vs 48.3%, P < 0.001). In addition, hemicolectomy had a better survival benefit than appendicectomy for patients with appendiceal MANEC, regardless of lymph node metastasis (P < 0.05). Tumor location, histology grade III, tumor size > 2 cm, T3-T4 stage, lymph node metastasis, and distant metastasis were independent prognostic factors for patients with MANEC.

CONCLUSIONS

Tumor location had an important prognostic significance for MANEC. As an uncommon clinical entity, colorectal MANEC had more aggressive biological features and worse prognosis than its appendiceal counterpart. The standard surgical procedure and clinical management strategy for MANEC need to be established.

Mixed small cell neuroendocrine carcinoma and squamous cell carcinoma covered by tubulovillous adenoma in the rectum: a case report and detailed molecular analyses

BACKGROUND

Previously, only six cases of mixed neuroendocrine-non-neuroendocrine neoplasm (MiNENs) with squamous cell carcinoma (SCC) component have been described in the colorectum, and the molecular landscape of MiNENs is also poorly understood. Herein, we present a unique case in which the SCC developed as a component of a MiNEN in the rectum.

CASE PRESENTATION

The patient was firstly diagnosed as rectal small cell neuroendocrine carcinoma (SCNEC) covered by tubulovillous adenoma, and then mixed SCNEC and SCC in the same site 6 months later. Representative samples from the three histologic subtypes were then sent for next-generation sequencing (NGS) separately. Multiple liver metastases occurred in the following month after the last surgery. The patient died of ketoacidosis 1 year after initial diagnosis of the tumor.

CONCLUSION

This is the first report of this exceedingly rare tumor type to include NGS of the 3 separate morphological entities. Our findings may expedite the understanding of combined tumors in the colorectum.

Comprehensive analysis of mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs): A SEER database analysis of 767 cases

Background

Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is an extremely rare entity, consisting of neuroendocrine and non-neuroendocrine components. It can occur in various organs throughout the body, with a rising incidence. Its clinical management is a rapidly growing field of interest; however, large-scale patient cohorts are still missing to guide clinical practice.

Patients and methods

The demographic, clinicopathological, and survival information of all patients diagnosed with MiNEN in the national Surveillance, Epidemiology, and End Results (SEER) program database (2000-2017) were extracted and further analyzed. The information of the patients before and after 2010 was compared to understand the epidemiological changes of MiNEN. The characteristics of MiNEN originating in different organs were compared. The clinical significance of surgical resection for metastatic MiNENs was also analyzed.

Results

A total of 1081 patients were screened, and after applying the exclusion criteria, 767 patients were finally analyzed. There was no obvious sex preference (49.2% vs 50.8%, p>0.05) and the majority of the patients were Caucasians (n=627, 81.7%). A total of 88.3% of the patients were older than 50 years old, and the median age was 60 years. 79.3% of the tumors are located in the distal digestive tract, and 67.7% were grade 3/4. Distant metastasis was presented in 33.9% of the patients at diagnosis. A total of 88% of the patients underwent surgical treatments. The number of patients increased 10-fold between 2000 and 2017. There was no significant difference in sex, race, stage, or surgical treatments among the patients diagnosed before and after 2010. More patients older than 60 years were diagnosed after 2010 (p=0.009). The median survival was 61.0 ± 9.8 months for the whole cohort. After multivariate analysis, older age (>60 years, p<0.01), more advanced stage (p<0.01), grade 3/4 (p<0.01), and non-surgical treatment (p<0.01) were independent risk factors for poorer survival. The appendiceal MiNENs showed the best prognosis. A total of 260 metastatic MiNENs were further analyzed. Only patients with metastatic MiNENs originating from the appendix had a potential benefit from surgical resection, compared to other sites (p=0.05).

Conclusion

This study provides the epidemiological, clinicopathological, and survival information of the largest number of MiNEN patients. Although MiNEN is an extremely rare malignant neoplasm, its incidence increases rapidly. The majority of the patients suffered from advanced-stage disease, which highlights the need for improvement of early detection in the future. The appendix is the most common primary site of MiNEN, and surgical resection for selected metastatic MiNEN originating in the appendix has favorable survival outcomes.

A bayesian approach to model the underlying predictors of early recurrence and postoperative death in patients with colorectal Cancer

Objective

This study aimed at utilizing a Bayesian approach semi-competing risks technique to model the underlying predictors of early recurrence and postoperative Death in patients with colorectal cancer (CRC).

Methods

In this prospective cohort study, 284 patients with colorectal cancer, who underwent surgery, referred to Imam Khomeini clinic in Hamadan from 2001 to 2017. The primary outcomes were the probability of recurrence, the probability of Mortality without recurrence, and the probability of Mortality after recurrence. The patients ‘recurrence status was determined from patients’ records. The Bayesian survival modeling was carried out by semi-competing risks illness-death models, with accelerated failure time (AFT) approach, in R 4.1 software. The best model was chosen according to the lowest deviance information criterion (DIC) and highest logarithm of the pseudo marginal likelihood (LPML).

Results

The log-normal model (DIC = 1633, LPML = -811), was the optimal model. The results showed that gender(Time Ratio = 0.764: 95% Confidence Interval = 0.456–0.855), age at diagnosis (0.764: 0.538–0.935 ), T₃ stage (0601: 0.530–0.713), N₂ stage (0.714: 0.577–0.935 ), tumor size (0.709: 0.610–0.929), grade of differentiation at poor (0.856: 0.733–0.988), and moderate (0.648: 0.503–0.955) levels, and the number of chemotherapies (1.583: 1.367–1.863) were significantly related to recurrence. Also, age at diagnosis (0.396: 0.313–0.532), metastasis to other sites (0.566: 0.490–0.835), T₃ stage (0.363: 0.592 − 0.301), T₄ stage (0.434: 0.347–0.545), grade of differentiation at moderate level (0.527: 0.387–0.674), tumor size (0.595: 0.500–0.679), and the number of chemotherapies (1.541: 1.332–2.243) were the significantly predicted the death. Also, age at diagnosis (0.659: 0.559–0.803), and the number of chemotherapies (2.029: 1.792–2.191) were significantly related to mortality after recurrence.

Conclusion

According to specific results obtained from the optimal Bayesian log-normal model for terminal and non-terminal events, appropriate screening strategies and the earlier detection of CRC leads to substantial improvements in the survival of patients.

Mixed neuroendocrine-nonneuroendocrine neoplasms of the gastrointestinal system: An update

Mixed neuroendocrine-nonneuroendocrine neoplasms (MiNENs) of the digestive tract are a rare heterogeneous group of tumors that present many challenges in terms of diagnosis and treatment. Over the years, the diagnostic criteria, classification, and clinical behavior of these tumors have been the subjects of ongoing debate, and the various changes in their nomenclature have strengthened the challenges associated with MiNENs. This review is performed to provide an understanding of the key factors involved in the evolution of the designation of these tumors as MiNEN, highlight the current diagnostic criteria, summarize the latest data on pathogenesis and provide information on available treatments. Moreover, this work seeks to increase the awareness about these rare neoplasms by presenting the clinicopathological features and prognostic factors that play important roles in their behavior and discussing their different regions of origin in the gastrointestinal system (GIS). Currently, the MiNEN category also includes tumors in the GIS with a nonneuroendocrine component and epithelial tumors other than adenocarcinoma, depending on the organ of origin. Diagnosis is based on the presence of both morphological components in more than 30% of the tumor. However, this value needs to be reconfirmed with further studies and may be a limiting factor in the diagnosis of MiNEN by biopsy. Furthermore, available clinicopathological data suggest that the inclusion of amphicrine tumors in the definition of MiNEN is not supportive and warrants further investigation. The diagnosis of these tumors is not solely based on immunohistochemical findings. They are not hybrid tumors and both components can act independently; thus, careful grading of each component separately is required. In addition to parameters such as the metastatic state of the tumor at the time of diagnosis and the feasibility of surgical resection, the aggressive potential of both components has paramount importance in the choice of treatment. Regardless of the organ of origin within the GIS, almost MiNENs are tumors with poor prognosis and are frequently encountered in the elderly and men. They are most frequently reported in the colorectum, where data from molecular studies indicate a monoclonal origin; however, further studies are required to provide additional support for this origin.