Neuroendocrine Carcinoma Patients Research Articles

Predictive Nomogram and Propensity Score Matching in Neuroendocrine Carcinoma of the Tubular Gastrointestinal Tract: A US Population-Based Clinical Outcome Study

Background: Neuroendocrine carcinomas (NECs) of the tubular gastrointestinal tract (GI-NECs) are rare and associated with worse clinical outcomes. This population-based study aims to highlight key demographics, clinicopathological factors, and survival outcomes in the US population. Methods: Data from 10,387 patients with GI-NECs were extracted from the Surveillance, Epidemiology, and End Result (SEER) database from 2000 to 2020. Results: Most patients were >40 years old at the time of presentation with a median age of 63 years old, with almost equal ethnic distribution per US population data. The most common primary tumor site was the small intestine (33.6%). The metastatic spread was localized in 34.8%, regional in 27.8%, and distant in 37.3% of cases, and the liver was the most common site of metastasis (19.9%) in known cases of metastases. Most NEC patients underwent surgery, presenting the highest 5-year overall survival of 73.2% with a 95% confidence interval (CI) (95% CI 72.0–74.4%), while chemotherapy alone had the lowest 5-year survival of 8.0% (95% CI 6.4–10.0%). Compared to men, women had a superior 5-year survival rate of 59.0% (95% CI 57.6–60.5%). On multivariate analysis, age > 65 (HR 2.49, 95% CI 2.36–2.54%, p ≤ 0.001), distant metastasis (HR 2.57, 95% CI 2.52–2.62%, p ≤ 0.001), tumor size > 4 mm (HR 1.98, 95%, CI 1.70–2.31%, p ≤ 0.001), esophageal (HR 1.49, 95% CI 0.86–2.58%, p ≤ 0.001), transverse colon (HR 1.95, 95% CI 1.15–3.33%, p ≤ 0.01), descending colon (HR 2.12, 95% CI 1.12, 3.97%, p = 0.02) anorectal sites, and liver or lung metastases were associated with worse survival. Surgical intervention and tumors located in the small intestine or appendix showed a better prognosis. Conclusion: GI-NECs are a group of rare malignancies associated with a poor prognosis. Therefore, epidemiological studies analyzing national databases may be the best alternative to have a more comprehensive understanding of this condition, assess the impact of current practices, and generate prognosis tools.

HER2 mutations in advanced cervical neuroendocrine carcinoma: implications for trastuzumab deruxtecan therapy.

Recent clinical evidence shows that the antibody-drug conjugate (ADC) trastuzumab deruxtecan (T-DXd) can successfully treat patients with advanced HER2-mutant non-small cell lung cancer (NSCLC). We aimed to characterize HER2 mutations in cervical neuroendocrine carcinoma (NEC) among Taiwanese women to provide the rationale for exploring T-DXd as a tumor-agnostic targeted therapy option. We analyzed 12 archived primary cervical NEC samples from Taiwanese patients. Tumor-rich areas were marked for microdissection on 10 μm unstained sections. DNA was extracted, and HER2 hotspots were sequenced using a targeted panel on the Illumina MiSeq. HER2 missense mutations were identified in 5 of 12 cases (41.7%). Of the 5 cases with mutations, 2 patients (40%) had a single mutation, while 3 patients (60%) had double mutations. We detected 4 substitutions outside the tyrosine kinase domain (non-TKD), which were p.P1170A, p.S305C, p.I655V, and a novel T328K alteration. No mutations were found within the tyrosine kinase domain (TKD). The 41.7% HER2 mutation rate warrants expanded screening and future clinical investigation of the T-DXd targeting HER2 mutations in cervical NEC patients. Overall, this study contributes to the molecular understanding of cervical NEC and lays the groundwork for developing more effective treatment strategies.

Clonality Analysis for the Relationship between the Pulmonary Combined Neuroendocrine Carcinoma and “the So-Called Reported Histologic Transformation”

Histologic transformation (HT) is common following targeted therapy in adenocarcinoma. However, whether the transformed tumor is a new component or a combined neuroendocrine carcinoma (C-NEC) remains controversial. We aimed to explore the relationship between pulmonary C-NEC and HT. Macro-dissection was performed on different components of surgically resected C-NEC samples. Molecular alterations and clonal evolution were analyzed using whole exome sequencing (WES). The gene statuses for TP53 and RB1 were determined using immunohistochemistry (IHC) and WES to analyze the relationship between C-NEC and reported HT. Sixteen combined small-cell lung cancer patients and five combined large-cell neuroendocrine carcinoma patients were enrolled. The frequency of p53 and Rb inactivation, assessed using IHC in NEC and non-NEC components, was 76.2/76.2% and 66.7/61.9%, respectively. The expression consistency between the components was 81.0 and 85.7% for p53 and Rb, respectively. The frequencies of TP53, RB1, and EGFR mutations, assessed using WES in NEC and non-NEC components, were 81.0/81.0%, 28.6/28.6%, and 42.9/42.9%, respectively. The concordance rates for TP53, RB1, and EGFR were 90.5, 71.4, and 90.5%, respectively. The consistency rate between IHC and WES was 81.0 and 61.9% for TP53 and RB1, respectively. The different components had a common clonal origin for the 21 C-NECs in the clonal analysis, consistent with previous studies on HT. Our study shows that IHC is more sensitive for Rb detection and C-NEC, and the reported HT may be due to differences in evaluations between pathologist and clinicians. Assessing the p53/Rb and EGFR status for such cases would help in recognizing potential transformation cases or uncovering potential combined components.

Value of a preoperative prognostic nutritional index for the prognostic evaluation of gastric neuroendocrine carcinoma patients.

To study the value of Onodera's prognostic nutrition index (PNI) in patients with gastric neuroendocrine cancer (G-NEC). The clinical data on 148 cases of G-NEC presented between March 2010 and April 2022 were retrospectively analyzed. The relationship between the clinical characteristics of the patients and PNI was analyzed. Optimal PNI cutoff values for G-NEC prognosis prediction were calculated using the X-tile software. The survival curves were created using the Kaplan-Meier method. A Cox proportional hazards model was also established to identify independent prognostic factors that impact the prognosis of patients with G-NEC. The median overall survival (OS) rate was 30 months (range 6-127 months), and the OS rates at 1, 3 and 5 years were 89.2, 71.6 and 68.2%, respectively. The mean PNI of the 148 patients before the operation was 49.5 ± 8.0. The mean PNI of patients with anemia (p < 0.001) and abnormal carcinoembryonic antigen (p = 0.039) was significantly lower than that of patients without such comorbidities. The mean PNI of patients with Stage III tumors (p < 0.001) and postoperative complications was significantly lower (p = 0.005). PNI optimal cutoff values were 50 (p < 0.001). Based on the cut-off value of the PNI, these patients were divided into a PNI-high group (PNI ≥ 50.0, n = 77) and a PNI-low group (PNI < 50.0, n = 71). The PNI-high group had a significantly better 5-years OS rate compared with the PNI-low group (76.6% vs. 59.2%, χ2 = 14.7, p < 0. 001). Multivariate analysis demonstrated that PNI and pathological stage were independent prognostic factors for patients with G-NEC. In the subgroup analysis, OS rates were significantly lower in the PNI-low group than in the PNI-high group among patients with stage I and stage III of the disease. The PNI is a simple and useful marker for predicting long-term outcomes in G-NEC patients regardless of tumor stage. Based on our results, we suggest that PNI should be included in routine assessments of patients with G-NEC.

Real world outcome of neuroendocrine carcinomas of the bladder compared to conventional tumors of the bladder.

e16591 Background: Platinum based neoadjuvant chemotherapy (NAC) has been shown to be a beneficial treatment strategy that increases overall survival (OS) in bladder cancer (BC) when compared to radical cystectomy (RC) alone, and the benefit was observed in multiple histologies associated with BC. Neuroendocrine carcinomas (NEC) of the bladder are a rare and aggressive BC subtype known to be chemotherapy sensitive, with improvement in oncological outcomes after NAC. However, due to inherent differences in natural progression of different BC histologies, higher chemosensitivity does not necessarily mean NEC has better outcomes compared to other BC histologies after NAC. We analyzed the outcomes of NEC patients and non-NEC BC patients to investigate the differences in benefit observed from NAC, and in oncological outcomes. Methods: Patients with BC that underwent cystectomy from 2000 to 2022 at the Cleveland Clinic Foundation were identified. Patients with NEC at transurethral resection (TUR) or cystectomy, and patients with BC with other pathologies (non-NEC) were selected. pCR was defined as downstaging from tumor presence in diagnostic resection to no residual tumor (pT0N0) after NAC. Survival outcomes of interest included recurrence-free survival (RFS) and OS. Results: A total of 562 cases of BC that underwent RC were identified. Of these, 50 patients included a diagnosis of NEC in their pathology report, either in TUR (n=42), or in RC (n=8) with 36% (18/50) of them with NEC without an associated conventional urothelial cell carcinoma (UCC), while 502 patients were diagnosed with UCC, with or without variant histologies and 10 patients with other histologies without UCC. Among patients with NEC, median age was 69 and M:F-45:5. When NEC patients were compared to non-NEC BC patients, they were more likely to present with muscle invasive bladder cancer (MIBC), (83% vs 60%; p=0.003) and receive NAC (86% vs 35%; p&lt;0.001) Most common chemotherapy regimen used in NEC patients was combination platinum and etoposide (26/36), compared to platinum and gemcitabine in non-NEC BC patients (141/184). pCR rate was 36% (13/36) in NEC, compared to 20% (36/184) in non-NEC cohort. (p=0.046). In terms of survival outcomes, RFS and OS were similar between the two groups (log-rank p-values 0.08 and 0.14, respectively). Conclusions: NAC prior to RC is beneficial in NEC of the bladder as a higher proportion achieve pCR when compared to non-NEC BC. In our cohort, despite presenting with more advanced disease, oncologic outcomes after NAC with RC were similar between the two groups. [Table: see text]

Primary tumor resection enhances the survival of pancreatic neuroendocrine carcinoma patients with liver metastasis under the definition of 2019 WHO classification.

With the update and release of the newest version of WHO classification (2019) for neuroendocrine neoplasm, the clinical features, risk factors of prognosis and the effect of surgical treatment on newly classified pancreatic neuroendocrine carcinoma (pNEC) patients with liver metastasis were not deeply analyzed. In the present study, we tried to reveal the clinical features, and prognostic factors of pNEC patients with liver metastasis with the newest definition of WHO 2019, and explore whether primary tumor resection (PTR), chemotherapy and radiotherapy affect overall survival (OS) and cancer-specific survival (CSS) in those patients. We collected data from pNEC patients with liver metastasis from the Surveillance, Epidemiology, and End Results (SEER) database who were diagnosed between 2010 and 2019. We strictly selected pNEC patients according to the 2019 WHO classification criteria. The univariate and multivariate Cox regression analysis were used to determine independent predictors of the survival of these patients. The forest plots map was drawn by R-4.2.2 software to display the results of the multivariate analysis visually. Kaplan-Meier method was used to estimate the OS and CSS. Based on the multivariate analysis outcomes, we established the predictable nomogram model to predict the prognosis of pNEC patients with liver metastasis. The calibration plots were shown to prove the predictive value of the nomogram predictable model. We identified 205 eligible pNEC patients with liver metastasis. According to the multivariable Cox regression analysis in this study, we found that PTR, chemotherapy, primary tumor size and diagnosis to treatment time were independent prognostic factors for both OS and CSS. Kaplan-Meier survival curves demonstrated that PTR and chemotherapy were correlated with increased survival for pNEC patients with liver metastasis. The accuracy of the nomogram model was visually proved by the calibration plot with acceptable predictive performance. Four independent predictors of prognosis in pNEC patients with liver metastasis were identified in this study, including PTR, chemotherapy, tumor size and diagnosis to treatment time. PTR and chemotherapy for pNEC with liver metastasis could lead to a better prognosis, which may provide inspiration for practical clinical guidelines.

Abstract CT218: A phase II trial of niraparib plus dostarlimab in relapsed small cell lung cancer and other high-grade neuroendocrine carcinomas

Abstract Objectives: Small cell lung cancer (SCLC) and high-grade neuroendocrine carcinomas (NECs) share many clinical features, including limited response to immune checkpoint inhibitors (ICIs). However, preclinical data suggest synergistic response with combined ICI and poly (ADP-ribose) polymerase inhibitors (PARPi) in SCLC models. This single-institution, phase II trial (NCT04701307) assessed the efficacy of a combination of the anti-PD-1 monoclonal antibody, dostarlimab, with the selective PARPi, niraparib, in patients with relapsed SCLC or NECs. Methods: Eligible patients with SCLC (Cohort 1) or NECs (Cohort 2) had received at least one prior line of therapy and were treated with niraparib 300 mg (or 200 mg if &amp;lt;77kg or platelets &amp;lt; 150,000/µL) PO daily, and dostarlimab 500 mg IV q21d (1000mg IV q42d starting with Cycle 5). Co-primary endpoints were objective response rate (ORR) by RECISTv1.1 and 6-month progression free-survival (PFS6). Using a Bayesian Optimal Phase 2 (BOP2) design, interim futility analyses were planned after enrolling up to 15 SCLC and 9 NEC patients (NEC), respectively. Adverse events (AE) were monitored continuously. Patients underwent biopsies, if feasible, at Cycle 1 and Cycle 3, as well as longitudinal plasma collection for translational studies. Results: From Feb 2021 to Aug 2021, 14 and 9 patients enrolled with SCLC and NEC, respectively. NECs included tumors from gynecological, head/neck, and gastrointestinal sites. In Cohort 1 (SCLC), 12 of 14 patients were evaluable by RECISTv1.1, including 1 complete response (CR), while 4 patients not achieving partial response (PR) had minor responses (-2%, -14%, -19%, and -24% from baseline). Only 1 patient in this cohort achieved PFS6, though 2 additional patients progressed between 5 and 6 months. In Cohort 2 (NEC), 6 of 9 patients were evaluable by RECISTv1.1 and no CR/PRs were observed. One patient did experience durable minor response (-21%), but no patients achieved PFS6. Dose-limiting, niraparib-related hematological AEs, typically thrombocytopenia, occurred in 12 of 23 patients. Non-hematological, treatment-related serious AEs occurred in only 1 patient (Grade 3 inflammatory arthritis), while 1 additional patient experienced brief dose-interruption due to Grade 2 pneumonitis. Preliminary translational data, including bulk and single-cell RNAseq, indicate molecular features, such as transcriptional subtype, are shared across SCLC and NECs and may predict response to this combination. Conclusions: In heavily pre-treated patients across SCLC and NEC cohorts, combined niraparib and dostarlimab failed to exceed interim futility criteria. However, multiple SCLC patients experienced durable disease control, including one patient with sustained CR and associated translational studies point to potential biomarker-driven approaches in the future. Trial supported by GlaxoSmithKline. Citation Format: Carl M. Gay, C. Allison Stewart, Michael Frumovitz, Junya Fujimoto, Yuann xi, Qi Wang, Runsheng Wang, Veronica Novegil, Mehmet Altan, Tina Cascone, Arvind Dasari, Yasir Y. Elamin, Frank V. Fossella, Bonnie S. Glisson, Charles S. Lu, Marcelo V. Negrao, Ferdinandos Skoulidis, Natalie Vokes, Robert J. Cardnell, Ignacio I. Wistuba, Jing Wang, John V. Heymach, Lauren A. Byers. A phase II trial of niraparib plus dostarlimab in relapsed small cell lung cancer and other high-grade neuroendocrine carcinomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT218.

Differences in clinical characteristics and prognosis between breast neuroendocrine carcinoma and breast invasive ductal carcinoma: A multicentre population-based study from China.

We constructed a multicentre cohort in China to analyse the differences in clinical characteristics, treatment strategies and prognoses between breast neuroendocrine carcinoma (NEC) and invasive ductal carcinoma (IDC) of the breast. All patients with early-stage breast cancer who attended three hospitals in Beijing from 2000 to 2018 were included in the study. We used propensity score matching to make a 1:3 match between NEC and IDC. After propensity score matching, 153 patients with IDC and 51 patients with NEC were analysed. Multivariate Cox regression showed that compared to patients with IDC, patients with NEC had a worse disease-free survival (HR=2.94, 95% CI: 1.69-5.12, p < 0.001). NEC patients have a worse disease-free survival than IDC patients.

Primary tumor resection improves survival of gastrointestinal neuroendocrine carcinoma patients with nonresected liver metastases.

The role of primary tumor resection (PTR) in the survival of gastrointestinal neuroendocrine carcinoma (GI-NEC) patients with liver metastases only remains poorly defined. Therefore, we investigated the impact of PTR on the survival of GI-NEC patients with nonresected liver metastases. GI-NEC patients with a liver-confined metastatic disease diagnosed between 2016 and 2018 were identified in the National Cancer Database. Multiple imputations by chained equations were used to account for missing data, and the inverse probability of treatment weighting (IPTW) method was used to eliminate selection bias. Overall survival (OS) was compared by adjusted Kaplan-Meier curves and log-rank test with IPTW. A total of 767 GI-NEC patients with nonresected liver metastases were identified. Among all patients, 177 (23.1%) received PTR and had a significantly favorable OS before (median: 43.6 months [interquartile range,IQR, 10.3-64.4] vs. 8.8 months [IQR, 2.1-23.1], p < 0.001 in log-rank test) and after (median: 25.7 months [IQR, 10.0-64.4] vs. 9.3 months [IQR, 2.2-26.4], p < 0.001 in IPTW-adjusted log-rank test) the IPTW adjustment. Additionally, this survival advantage persisted in an adjusted Cox model (IPTW adjusted hazard ratio = 0.431, 95% confidence interval: 0.332-0.560; p < 0.001). The improved survival persisted in subgroups stratified by primary tumor site, tumor grade, and N stage, even in the complete cohort (excluding patients with missing data). PTR led to improved survival for GI-NEC patients with nonresected liver metastases regardless of primary tumor site, tumor grade, and N stage. However, the decision for PTR should be made on an individualized basis following multidisciplinary evaluation.

Genetic alterations of GI-NECs involving three main signaling pathways.

Gastrointestinal (GI)-neuroendocrine neoplasms (NENs) are subclassified in neuroendocrine tumors (NETs), neuroendocrine carcinomas (NECs), and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs). The genetic characteristics of GI-NEN has been a hot issue in recent years, but more studies are needed to provide further details. This study aims to provide additional data about genomic characteristics of GI-NENs and the genetic differences between NETs and NECs. Thirteen samples were selected for next-generation sequencing (NGS) analysis with a 425-gene panel. Microsatellite instability (MSI) and tumor mutational burden (TMB) were calculated as well as immunohistochemistry (IHC) was used to test for protein expression. Genetic alterations were very common in NECs, but rare in NETs. The average TMB of NETs and NECs was 2.3 and 6.9, respectively. The TMB of NECs was significantly higher compared to NETs. The TP53 mutation rate was significantly higher in NECs than in NETs (100% vs. 20%), other mutations involved MTOR (n= 2, 15.4%), DDR2 (n= 3, 23.1%), ERBB4 (n= 1, 7.7%), BRCA1 (n= 1, 7.7%), BRCA2 (n= 1, 7.7%), ATM (n= 1, 7.7%), and SMAD4 (n= 1, 7.7%). Deep loss of SMAD4 (1/3, 33.3%), SDHB (1/3, 33.3%), RB1 (1/3, 33.3%), and BRCA2 (1/3, 33.3%), high-level amplification of CRKL (1/3, 33.3%), CCNE1(1/3, 33.3%), and MCL1(1/3, 33.3%) were found in NECs. The integrated analysis found these genetic alterations frequently involve DNA repair and cell cycle, PI3K/AKT/mTOR and TGF-β/SMAD4 signaling pathways. Genetic alterations were very common in NECs and rare in NETs, and frequently involved three main signaling pathways. NEC patients harboring these genetic alterations may benefit from targeted therapy and PD-1/PD-L1 immunotherapy.

Nomogram to predict overall survival in patients with primary bladder neuroendocrine carcinoma: a population-based study.

Aim: To develop a prognostic model to predict the overall survival of primary bladder neuroendocrine carcinoma (BNEC) patients. Methods: Using univariate and multivariate Cox regression analyses, a nomogram was constructed. Calibration curves, receiver operating characteristic curvesand C-index were utilized to evaluate the performance. Results: The study enrolled 906 BNEC patients. The following variables were incorporated in the nomogram: age, marital status, Tumor node metastasis (TNM) stage, chemotherapyand surgery. The nomogram had a C-index of 0.702 in the training cohortand 0.724 in the validation cohort. Conclusion: Compared with the TNM staging system, the proposed nomogram exhibits superior prognostic discrimination and survival prediction.

Prognostic Factors across Poorly Differentiated Neuroendocrine Neoplasms: A Pooled Analysis

Introduction: Poorly differentiated neuroendocrine carcinomas (NECs) are characterized by aggressive clinical course and poor prognosis. No reliable prognostic markers have been validated to date; thus, the definition of a specific NEC prognostic algorithm represents a clinical need. This study aimed to analyze a large NEC case series to validate the specific prognostic factors identified in previous studies on gastro-entero-pancreatic and lung NECs and to assess if further prognostic parameters can be isolated. Methods: A pooled analysis of four NEC retrospective studies was performed to evaluate the prognostic role of Ki-67 cut-off, the overall survival (OS) according to primary cancer site, and further prognostic parameters using multivariable Cox proportional hazards model and machine learning random survival forest (RSF). Results: 422 NECs were analyzed. The most represented tumor site was the colorectum (n = 156, 37%), followed by the lungs (n = 111, 26%), gastroesophageal site (n = 83, 20%; 66 gastric, 79%) and pancreas (n = 42, 10%). The Ki-67 index was the most relevant predictor, followed by morphology (pure or mixed/combined NECs), stage, and site. The predicted RSF response for survival at 1, 2, or 3 years showed decreasing survival with increasing Ki-67, pure NEC morphology, stage III–IV, and colorectal NEC disease. Patients with Ki-67 <55% and mixed/combined morphology had better survival than those with pure morphology. Morphology pure or mixed/combined became irrelevant in NEC survival when Ki-67 was ≥55%. The prognosis of metastatic patients who did not receive any treatment tended to be worse compared to that of the treated group. The prognostic impact of Rb1 immunolabeling appears to be limited when multiple risk factors are simultaneously assessed. Conclusion: The most effective parameters to predict OS for NEC patients could be Ki-67, pure or mixed/combined morphology, stage, and site.

Novel staging for gastric neuroendocrine neoplasms by incorporating the WHO grading into the TNM staging system.

The 8th tumor-node-metastasis (TNM) classification of the American Joint Committee on Cancer (AJCC) can be used to estimate the prognosis of gastric neuroendocrine tumor (gNET) and gastric neuroendocrine carcinoma (gNEC) patients but not gastric neuroendocrine neoplasms (gNENs). First, in the SEER (training) dataset, a TNMG system was built by combining the WHO G grade (G1-4; NEC grouped into G4) with the 8th AJCC T (T1-4), N (N0-1), and M (M0-1) stage, which was then validated in a Chinese (validation) cohort. In all, 2245 gNENs cases from the training dataset and 280 cases from the validation dataset were eligible. The T stage, M stage, and G grade were independent prognostic factors for OS in both datasets (all p <0.05). The TNMG staging system demonstrated better C-index for predicting OS than the 8th AJCC TNM staging system in both the training (0.87, 95%CI: 0.86-0.88 vs. 0.79, 95%CI: 0.77-0.81) and validation (0.77, 95%CI: 0.73-0.80 vs. 0.75, 95%CI: 0.71-0.79) datasets. The AUC of the 3-year OS for the TNMG staging system was 0.936 and 0.817 in the SEER and validation dataset, respectively; higher than those of the 8th AJCC system (vs. 0.843 and 0.779, respectively). DCA revealed that compared with the 8th AJCC TNM staging system, the TNMG staging system demonstrated superior net prognostic benefit in both the training and validation datasets. The proposed TNMG staging system could more accurately predict the 3- and 5-year OS rate of gNENs patients than the 8th AJCC TNM staging system.

Second-line treatment and prognostic factors in neuroendocrine carcinoma: the RBNEC study

Neuroendocrine carcinomas (NEC) are aggressive malignant diseases. Etoposide-based rechallenge (EBR) and the prognostic role of RB transcriptional corepressor 1 (RB1) status in second-line chemotherapy (2L) have not been studied. The objectives of this study were to report the results of 2L including EBR as well as prognostic factors in a national retrospective multicentre study. NEC patients treated with 2L and further, with tissue samples available, were included. RB1 status and morphological classification were reviewed centrally. Among the 121 NEC patients (40% female, median age 61 years) included, there were 73 small-cell NEC (60%), 34 large-cell NEC (28%) and 14 NEC (not otherwise specified, 12%). Primary sites were lung (39%), gastroenteropancreatic (36%), other (13%) and unknown (12%). Median Ki-67 index was 80%. Median progression-free survival (PFS) and overall survival (OS) under 2L were 2.1 and 6.2 months, respectively. No difference was observed between patients who received an 'adenocarcinoma-like' or a 'neuroendocrine-like' 2L or according to the RB1 status. Thoracic NEC primary was the only adverse prognostic factor for OS. EBR, administered to 31 patients, resulted in a 62% disease control rate with a median PFS and OS of 3.2 and 11.7 months, respectively. In the 94 patients with a relapse-free interval of ≥3 months after first-line platinum-etoposide chemotherapy, the median OS was 12 months in patients who received EBR as compared to 5.9 months in patients who did not (P = 0.043). EBR could be the best 2L option for patient with initial response to first-line platinum-etoposide lasting at least 3 months. RB1 status does not provide prognostic information in this setting.

890MO Mutation spectrum in liquid versus solid biopsies from advanced digestive neuroendocrine carcinoma patients

Digestive neuroendocrine carcinoma (NEC) are currently defined by the presence of a poorly differentiated neuroendocrine phenotype and a high proliferation rate (Ki-67>20%). Most digestive NEC are diagnosed with metastatic disease with survival less than 1 year if medically treated. Frequently only minor biopsies are available for further molecular diagnostics. The molecular characteristics of digestive NEC has recently been described, but data on applicability of liquid biopsies in digestive NEC is very limited. We performed massive parallel sequencing of 76 cancer related genes in plasma ctDNA from 50 patients with advanced digestive NEC and compared findings to previous analyses performed in matched FFPE tumour biopsies. Optimal filters were used, including data from WBC as filter for removal of SNPs. Among the 50 patients, 46 had metastatic disease and 4 locoregional disease at the time of plasma sampling. We detected a total of 178 somatic mutations in the liquid biopsies. Out of these, 127 (71%) were also detected in the solid biopsies. In the same 76 genes, we previously detected 199 somatic mutations (SNVs) in the tumor biopsies. Thus, 64% (127 out of 199) of mutations in solid biopsies were also found in the liquid biopsies. The concordance was higher in patients with liver metastases (p= p=1.5x10-5), while it was similar between digestive NEC with different primary sites, except for a lower concordance in esophageal cases (p=0.001). Concordance was not associated with tumor mutational burden (TMB). Tumour tissue mutations also detected in liquid biopsies was lower for MSI (40%) versus MSS tumours (70%; p=7.8x10-4). Applying a predefined set of criteria, we identified potentially targetable mutations in plasma of 26 (52%) of digestive NEC patients; 9 patients (18%) had potentially targetable mutation detected only in liquid biopsies. We found liquid biopsy analyses to be an applicable alternative to solid biopsies in digestive NEC patients. Liquid biopsies could be used for biomarker assessment in clinical trials for these patients.

Bcl-2 and Noxa are potential prognostic indicators for patients with gastroenteropancreatic neuroendocrine neoplasms.

Bcl-2 family proteins are of great significance in the pathogenesis and development of tumors. In this study, the correlations between the expression of Bcl-2 family proteins and clinicopathological features and prognosis of neuroendocrine neoplasms (NENs) were further investigated. 105 Patients diagnosed with gastroenteropancreatic NENs (GEP-NENs) with the paraffin specimen of the tumor available were retrospectively included. Immunohistochemistry (IHC) was performed to detect the expression of Bcl-2 family proteins in paraffin-embedded samples. Student's t-test and Chi-square test were applied to compare the difference of quantitative and categorical variables, respectively. Survival analysis was conducted according to Kaplan-Meier method. Univariate and multivariate cox regression analysis were used to identify the independent prognostic factors. The IHC score of Bcl-2 was significantly higher in neuroendocrine carcinoma (NEC) patients (65.6%), while a higher IHC score of Noxa was more common in neuroendocrine tumor (NET) patients (49.3%). Survival analysis indicated that patients with higher Bcl-2 expression and lower Noxa expression had worse 5-year survival (39.3% vs. 75.6%, p < 0.001; 40.6% vs. 84.9%, p < 0.001). Multivariate cox analysis indicated that high Bcl-2 expression was an independent factor associated with inferior DFS (hazard ratio [HR]: 2.092; 95% confidence interval [CI]: 1.106-3.955; p = 0.023) and OS (HR: 2.784; 95% CI: 1.326-5.846; p = 0.007), while higher Noxa expression was associated with superior DFS (HR:0.398; 95% CI: 0.175-0.907; p = 0.028) and OS (HR: 0.274; 95% CI: 0.110-0.686; p = 0.006). Higher expression of Bcl-2 and lower expression of Noxa were associated with unfavorable prognosis of GEP-NENs patients.

Clinicopathological and molecular profile of grade 3 gastroenteropancreatic neuroendocrine neoplasms.

The 2019Word Health Organization (WHO) subclassified grade 3 (G3) gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN) into neuroendocrine carcinoma (NEC) or tumours (G3NET) based on morphology and proliferation. Yet, few data exist on molecular profiles for G3NEN. We compared clinicopathological and molecular characteristics of these two groups. We retrospectively reviewed consecutive G3 GEP NEN patients and had their tumour tissues reviewed, reclassified as per the WHO 2019, and analyzed by a next-generation sequencing (NGS) panel. Between 2000 and 2019, 43 patients had pathology revision: 29 (67%) were NEC and 14 (33%) were G3NET, with a 23% change in diagnosis. Median overal survival for G3NET and NEC patients was 55.6 and 11.9months, respectively (hazard ratio=2.78 [95% confidence interval=1.09-7.11], p=.042), which was confirmed by an adjusted analysis (hazard ratio=2.90NEC vs. G3NET; p=.03). NGS was performed in 32 cases: 21NEC and 11 G3NET. Mutations in RB1 and PTEN were exclusively encountered in NEC. Median tumour mutational burden was 5 (0-67) mutations per megabase in NEC and 4.5 (0-9) among G3NET. Microsatellite instability was found in 3 (14.3%) NEC cases. In conclusion, pathology revision is essential to estimate prognosis and therapeutic plan. G3 GEP NEN generally harbour low tumor mutation burden and fewer actionable mutations, but 14% of NEC cases were microsatellite unstable and could benefit from immune checkpoint inhibitors.

Multicenter retrospective study of ramucirumab-containing chemotherapy for gastrointestinal neuroendocrine carcinoma patients previously treated with platinum-based chemotherapy: RAM-NEC study (WJOG13420G).

511 Background: Platinum-based systemic chemotherapy (CTx) is recommended for poorly differentiated advanced gastrointestinal neuroendocrine carcinoma (GI-NEC). As second-line CTx various regimens are adopted according to the guidelines of GI adenocarcinoma or small cell lung cancer in daily practice. Recently, some clinical and preclinical reports suggest that vascular endothelial growth factor (VEGF) inhibitors are effective against NEC. In this study, we evaluated the efficacy of ramucirumab (RAM, anti-VEGF receptor 2 antibody)-containing CTx. Methods: We retrospectively evaluated gastric (G-) or colorectal (C-) NEC patients previously treated with first-line platinum-based CTx followed by second-line CTx between March 2015 and June 2020 (G-NEC) or between May 2016 and June 2020 (C-NEC). The main inclusion criteria were ECOG performance status (PS) of 0–2, pathologically diagnosed as G or C- NEC or mixed adenoneuroendocrine carcinoma. We compared the efficacy of RAM-containing CTx as second- or later-line treatment (Group A) with that of CTx without RAM as second-line treatment (Group B). A Cox proportional hazard model and inverse probability weighting of propensity scores were used to adjust the background factors between the two groups. Results: From 25 facilities, 139 patients were included in this study. Group A and B contained 50 (G/C, 43/7 patients) and 89 (G/C, 58/31 patients) patients, respectively. Patient characteristics were as follows (Group A/Group B): median age (range), 70 (28–83)/68 (39–86); ECOG PS 1–2, 66/69%, more than two prior regimens, 46/0%; response to previous platinum-based CTx, 46/38%. The regimen in combination with RAM in Group A was paclitaxel/nab-paclitaxel/FOLFIRI (62/26/12%). Second-line CTx in Group B were commonly amrubicin (58%) and irinotecan (11%). The efficacy (Group A/Group B) after a median follow-up time of 7.5/5.5 months were as follows: median overall survival (mOS), 8.6/5.8 months (HR, 0.68; 95% CI, 0.45–1.01; p = 0.058); median progression-free survival, 4.3/1.9 months (HR, 0.57; 95% CI, 0.39–0.84; p = 0.004); objective response rate, 50/8% ( p &lt; 0.0001); disease control rate, 70/24% ( p &lt; 0.0001); mOS in G-NEC, 8.6/5.3 months (HR, 0.62; 95% CI, 0.39–0.99; p = 0.047); and mOS in C-NEC, 5.4/6.8 months (HR, 0.66; 95% CI, 0.26–1.66; p = 0.378). The most common grade 3 or higher treatment-related adverse event that occurred in more than 5% of patients in Group A was neutropenia (32%). Conclusions: This study suggests that RAM-containing CTx as second- or later-line treatment is effective for GI-NEC patients, especially for G-NEC. Central pathological review and biomarker analyses using pretreated tissue specimens are ongoing. We will present updated data in the congress. Clinical trial information: UMIN000043200.

Survival Analysis in Gastrointestinal Neuroendocrine Carcinoma With Bone Metastasis at Diagnosis.

PurposeGastrointestinal neuroendocrine carcinoma (NEC) with bone metastasis is rarely reported. The purpose of this study is to explore the prognosis and risk factors of such patients.Patients and MethodsWe retrospectively reviewed patients diagnosed as gastrointestinal NECs with bone metastasis at diagnosis from 2010 to 2016 by using the Surveillance, Epidemiology and End Results (SEER) database. Predictors of overall survival (OS) and cancer-specific survival (CSS) were analyzed by univariable and multivariable Cox analyses. Kaplan–Meier plots were constructed to show the correlation between independent predictors and survival.ResultsA total of 330 gastrointestinal NEC patients with bone metastasis at diagnosis were included for analysis. Over half of patients were male and older than 60 years old. The most common primary site of gastrointestinal NEC with bone metastasis was the pancreas. The prognosis of gastrointestinal NEC with bone metastasis (3-year OS and CSS rates: 16.7 and 17.0%) was very poor. On Cox multivariable analysis, age over 60 years old, no surgery, and lung metastasis were independent predictors of decreased OS and CSS.ConclusionsWe identified three independent factors associated with prognosis among gastrointestinal NEC patients with bone metastasis, namely age, surgery, and lung metastasis. For younger gastrointestinal NEC patients with bone metastasis, surgical resection of primary tumors as well as actively treating lung metastasis might be useful for prolonging survival.

Prognostic Values of MLNn and MLNr for Gastric Cancer Patients Receiving Chemoradiotherapy and Lesser Curvature Resection.

The goal was to investigate the prognostic values of metastatic lymph node number (MLNn) and ratio (MLNr) for gastric neuroendocrine carcinoma (GNEC) patients treated by neoadjuvant chemoradiotherapy combined with total resection of lesser curvature. Seventy-three patients were admitted between August 2018 and August 2021 to receive neoadjuvant chemoradiotherapy combined with total resection of lesser curvature were retrospectively analyzed. The indicators of lymph node involvement, including pathological N (pN) stage, MLNn, MLNr, and metastatic lymph node station (MLNs), and other clinicopathological data were analyzed. Of the 54 eligible patients, 44 (81%) had lymph node metastasis. The median survival time of the whole cohort was 63.2 months (14 - 153 months), and the 3- and 5-year survival rates were 88.9% and 47.9%, respectively. The medians of lymph nodes, MLNn, and MLNr were 19 (10 - 56), 5 (1 - 21), and 25% (6% - 100%), respectively. Cox regression analysis showed that pN1 (p = 0.0266), MLNn > 2 (p = 0.0091), MLNr > 0.1 (p = 0.0031), MLNs = 2 (p = 0.0119) and distant metastasis (p = 0.0021) were independent influencing factors for prognosis. In addition to pN stage, the indicators of metastatic lymph node involvement, including MLNn, MLNr, and MLNs are significant predictors for the survival of patients with GNEC, and distant metastasis is also a key prognostic factor. These indicators are crucial supplements to survival factors and can improve the risk classification of GNEC patients.