Molecular Subtypes of Pulmonary Large-cell Neuroendocrine Carcinoma Predict Chemotherapy Treatment Outcome

Spontaneous Transformation from Lung Adenocarcinoma to MYC-amplified Large Cell Neuroendocrine Carcinoma

Recent studies suggest that lung adenocarcinoma cells are closely associated with the tumorigenesis of large-cell neuroendocrine carcinoma via cellular transformation. However, morphological evidence, along with genetic abnormalities before, during, and after transformation, is quite limited. We present here a case of combined large-cell neuroendocrine carcinoma and adenocarcinoma exhibiting acinar and solid patterns. Adenocarcinoma cells with abundant mucin, exhibiting positivity for both napsin-A and neuroendocrine markers, were partially found in the acinar adenocarcinoma component and extensively observed in the solid adenocarcinoma component. Next-generation sequencing using extracted genomic DNA from the three components revealed homozygous TP53 (missense) and STK11 (nonsense) mutations in all three components, suggesting monoclonal origin. Furthermore, MYC gene amplification, recently presumed to be a pivotal driver in neuroendocrine transformation, was observed in both the solid adenocarcinoma and large-cell neuroendocrine carcinoma components. These genetic findings corresponded to pre- and post-transformation morphology, providing compelling evidence that some kinds of adenocarcinomas may serve as a precursor of large-cell neuroendocrine carcinoma.

Diagnostic relevance of p53 and Rb status in neuroendocrine tumors G3 from different organs: an immunohistochemical study of 465 high-grade neuroendocrine neoplasms

The double inactivation of TP53 and RB1 is considered typical of neuroendocrine carcinomas (NECs) but is assumed to be rare in high-grade neuroendocrine tumors (NETs). The immunohistochemical determination of the p53 and Rb status has therefore been proposed as a diagnostic tool. We studied this status in a large series of high-grade neuroendocrine neoplasms, from multiple origins, in order to (a) assess the patterns observed in the different histopathological categories, (b) compare them between the various anatomic sites, and (c) evaluate their possible diagnostic relevance. Four hundred sixty-five cases from 9 organ systems (142 high-grade NETs -NET-G3-, 162 large-cell NECs -LCNEC-, 144 small-cell NECs -SCNEC-) and 60 cases of NET G1/G2 were included. The expression of both proteins was normal in 96.7% of NET G1/G2, 76.7% of NET-G3, and 5.8% of all NECs. p53 expression was abnormal in 12.7% of NET-G3 and 91.5% of NECs. Rb expression was lost in 10.6% of NET-G3 and 68.3% of NECs. Rb loss was significantly less frequent in LCNEC than in SCNEC (57.3% versus 80.6%); abnormal p53 expression was comparable in the two categories. Patterns were comparable between primary sites, except for head and neck NECs. For diagnostic purposes, taking into account, Rb status improved, but only marginally, the performances of p53 status. In conclusion, our study underlines the molecular heterogeneity of NET-G3 and LCNEC, irrespectively of the primary, and provides further insight on the diagnostic relevance of p53/Rb immunodetection in high-grade neuroendocrine neoplasms.

Stereotactic radiosurgery for pancreatic neuroendocrine tumor brain Metastases: Systematic review and Illustrative case presentation

BACKGROUND

Neuroendocrine tumor (NET) brain metastases (BM) are rare malignancies which frequently bear a poor prognosis and have the potential to secrete hormones. The optimal treatment approach for these metastases remains unclear, with significant heterogeneity occurring both across and within primary tumor types, and outcome data are limited. Pancreatic neuroendocrine tumor (pNET) BM may be particularly aggressive. While stereotactic radiosurgery (SRS) for other NET BM has previously been described, no report has specifically investigated SRS for management of pNET BM.

METHODS

A comprehensive literature search was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Search terms included ("neuroendocrine tumor" OR "neuroendocrine neoplasm" OR "neuroendocrine carcinoma" OR "NET") AND ("brain metastasis" OR "brain metastases" OR "intracranial metastases") AND ("stereotactic radiosurgery" OR "stereotactic body" OR "CyberKnife" OR "GammaKnife").

RESULTS

Our search strategy yielded 230 articles. After screening, a total of 16 articles with 256 patients were identified. Number of patients per study cohort ranged from 1 to 101 (mean = 16). Ten articles were single case reports. The most commonly investigated primary site was lung (5 studies), followed by skin (2 case reports), and uterine cervix (2 case reports). Median survival post-SRS ranged from 5 to 42 months. Median tumor volume ranged from 0.08 cm3 to 33.62 cm3. Local control rate was provided in 3 of 6 of the reviewed retrospective analyses. A pulmonary cohort of 101 patients reported a recurrence rate of 13.8 % at 12 months. A pulmonary case series similarly reported local progression in only 1 of 8 patients. The mixed primary cohort (33 patients) had a long-term local failure rate of 16.7 %. In addition, we describe a first reported individual case of pNET BM treated with SRS. Nearly 6-years after initial pNET diagnosis, multiple intracranial enhancing lesions were found, which were subsequently treated with SRS. Follow-up imaging demonstrated a statistically significant decrease in lesion diameter (p < 0.001), with none of the 18 BM progressing.

CONCLUSION

Given the recently increase in age-adjusted incidence of NET BM, determining an optimal treatment approach for these malignancies is of growing importance. Prognosis generally remains poor, with BM being a significant predictor of overall survival. Our review indicated large variability in outcomes both between and within primary tumor types, suggesting a need for further investigation of predictive molecular biomarkers. In addition, to the authors' knowledge, this represents the first reported case of pNET BM successfully treated with SRS.

Clinical characteristics and treatment management of combined large cell neuroendocrine carcinoma, a subtype of large cell neuroendocrine carcinoma

Combined large cell neuroendocrine carcinoma (CLCNEC) is a rare neuroendocrine carcinoma, accounting for approximately 10% of large cell neuroendocrine carcinoma (LCNEC). Mainly composed of coexisting adenocarcinoma components, with strong invasiveness and poor prognosis. The treatment regimen for CLCNEC mainly refers to complete surgical resection as the first choice in the early stage, while patients with stage II or higher require adjuvant treatment. At present, research on CLCNEC is mostly small sample and retrospective, and there is no consensus on whether molecular typing and treatment should be carried out. There is considerable controversy over whether it should be managed as small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC). Therefore, in order to solve the problem of confusion in the selection of treatment regimens for CLCNEC, while also considering the therapeutic effects, this article summarizes and analyzes previous studies, fully seeks evidence, and boldly proposes new therapeutic insights: the etoposide-platinum (EP) regimen serves as the basis for adjuvant therapy; In addition, SCLC/NSCLC-CLCNEC can be distinguished based on presence of RB1 and TP53 co-mutation, and targeted therapy or NSCLC type chemotherapy including platinum + gemcitabine or taxanes (NSCLC-GEM/TAX) can be used in combination or sequentially for NSCLC-CLCNEC.

Implementing machine learning to predict survival outcomes in patients with resected pulmonary large cell neuroendocrine carcinoma

BACKGROUND

The post-surgical prognosis for Pulmonary Large Cell Neuroendocrine Carcinoma (PLCNEC) patients remains largely unexplored. Developing a precise prognostic model is vital to assist clinicians in patient counseling and creating effective treatment strategies.

RESEARCH DESIGN AND METHODS

This retrospective study utilized the Surveillance, Epidemiology, and End Results database from 2000 to 2018 to identify key prognostic features for Overall Survival (OS) in PLCNEC using Boruta analysis. Predictive models employing XGBoost, Random Forest, Decision Trees, Elastic Net, and Support Vector Machine were constructed and evaluated based on Area Under the Receiver Operating Characteristic Curve (AUC), calibration plots, Brier scores, and Decision Curve Analysis (DCA).

RESULTS

Analysis of 604 patients revealed eight significant predictors of OS. The Random Forest model outperformed others, with AUC values of 0.765 and 0.756 for 3 and 5-year survival predictions in the training set, and 0.739 and 0.706 in the validation set, respectively. Its superior validation cohort performance was confirmed by its AUC, calibration, and DCA metrics.

CONCLUSIONS

This study introduces a novel machine learning-based prognostic model with a supportive web-based platform, offering valuable tools for healthcare professionals. These advancements facilitate more personalized clinical decision-making for PLCNEC patients following primary tumor resection.

Head-to-head: Should Ki67 proliferation index be included in the formal classification of pulmonary neuroendocrine neoplasms?

The reporting of lung neuroendocrine neoplasms (NENs) according to the 2021 World Health Organisation (WHO) is based on mitotic count per 2 mm2, necrosis assessment and a constellation of cytological and immunohistochemical details. Accordingly, typical carcinoid and atypical carcinoid are low- to intermediate-grade neuroendocrine tumours (NETs), while large-cell neuroendocrine carcinoma (NEC) and small-cell lung carcinoma are high-grade NECs. In small-sized diagnostic material (cytology and biopsy), the noncommittal term of carcinoid tumour/NET not otherwise specified (NOS) and metastatic carcinoid NOS have been introduced with regard to primary and metastatic diagnostic settings, respectively. Ki-67 antigen, a well-known marker of cell proliferation, has been included in the WHO classification as a non-essential but desirable criterion, especially to distinguish NETs from high-grade NECs and to delineate the provisional category of carcinoid tumours/NETs with elevated mitotic counts (> 10 mitoses per mm2) and/or Ki-67 proliferation index (≥ 30%). However, a wider use of this marker in the spectrum of lung NENs continues to be highly reported and debated, thus witnessing a never-subsided attention. Therefore, the arguments for and against incorporating Ki-67 in the classification and clinical practice of these neoplasms are discussed herein in detail.

Early death incidence and prediction in stage IV large cell neuroendocrine carcinoma of the lung

Nearly half of lung large cell neuroendocrine carcinoma (LCNEC) patients are diagnosed at an advanced stage and face a high early death risk. Our objective was to develop models for assessing early death risk in stage IV LCNEC patients. We used surveillance, epidemiology, and end results (SEER) databases to gather data on patients with stage IV LCNEC to construct models and conduct internal validation. Additionally, we collected a dataset from the Second Affiliated Hospital of Nanchang University for external validation. We used the Pearson correlation coefficient and variance inflation factor to identify collinearity among variables. Logistic regression analysis and least absolute shrinkage and selection operator analysis were employed to identify important independent prognostic factors. Prediction nomograms and network-based probability calculators were developed. The accuracy of the nomograms was evaluated using receiver operating characteristic curves. The goodness of fit of the nomograms was evaluated using the Hosmer-Lemeshow test and calibration curves. The clinical value of the models was assessed through decision curve analysis. We enrolled 816 patients from the surveillance, epidemiology, and end results database and randomly assigned them to a training group and a validation group at a 7:3 ratio. In the training group, we identified 9 factors closely associated with early death and included them in the prediction nomograms. The overall early death model achieved an area under the curve of 0.850 for the training group and 0.780 for the validation group. Regarding the cancer-specific early death model, the area under the curve was 0.853 for the training group and 0.769 for the validation group. The calibration curve and Hosmer-Lemeshow test both demonstrated a high level of consistency for the constructed nomograms. Additionally, decision curve analysis further confirmed the substantial clinical utility of the nomograms. We developed a reliable nomogram to predict the early mortality risk in stage IV LCNEC patients that can be a helpful tool for health care professionals to identify high-risk patients and create personalized treatment plans.

Clinical and Pathologic Differences between Small-Cell Carcinoma and Large-Cell Neuroendocrine Carcinoma of the Lung

BACKGROUND

Both small-cell carcinoma (SCLC) and large-cell neuroendocrine carcinoma (LCNEC) of the lung are often clinically dealt with as being in the same category as neuroendocrine carcinoma, and their clinical differences have not been adequately assessed.

METHODS

The postoperative prognosis was retrospectively analyzed using the data of 196 patients who underwent resection for SCLC or LCNEC.

RESULTS

Of the patients included, 99 (50.5%) had SCLC and 97 (49.5%) had LCNEC. The median duration of follow-up was 39 months (interquartile range [IQR] 21-76) and 56 months (IQR 21-87) for SCLC and LCNEC, respectively. The estimated 5-year overall survival (OS) probabilities were 53.7% and 62.7% (p = 0.133) for patients with SCLC and LCNEC, respectively. In the SCLC group, a multivariate analysis showed that adjuvant chemotherapy (hazard ratio 0.54, 95% confidence interval 0.30-0.99, p = 0.04) was the only factor that was significantly associated with OS. In the LCNEC group, univariate analyses demonstrated that pathologic stage I (p = 0.01) was the only factor that was associated with better OS after surgery.

CONCLUSIONS

We found different clinical features in SCLC and LCNEC; in patients with SCLC, because OS could be expected to significantly improve with postoperative adjuvant chemotherapy, patients with resected SCLC of any pathologic stage should receive adjuvant chemotherapy. For patients with LCNEC, because pathologic stage I LCNEC is related to better prognosis than any other stages, a thorough clinical staging, including invasive staging, according to present guidelines should be performed to identify clinical stage I LCNEC with the highest certainty.

A randomized phase II trial of Captem or Folfiri as second-line therapy in neuroendocrine carcinomas

BACKGROUND

Neuroendocrine Carcinomas (NECs) prognosis is poor.No standard second-line therapy is currently recognized after failure of platinum-based first-line treatment. FOLFIRI and CAPTEM regimens have shown promising activity in preliminary studies. We aimed to evaluate these regimens in metastatic NEC patients.

METHODS

This is an open-label, multicenter, randomized non-comparative phase II trial to evaluate the activity and safety of FOLFIRI or CAPTEM in metastatic NEC patients. Primary endpoints were the 12 weeks-Disease Control Rate (12w-DCR) by investigator assessment per RECIST v1.1 and safety per CTCAE v5.0. Additional endpoints included overall response rate (ORR), progression-free survival (PFS) and overall survival (OS). Patients' serum samples were subject to NGS miRNome profiling in comparison with healthy donors to reveal differentially expressed miRNAs as candidate circulating biomarkers.

RESULTS

The study was halted for futility at interim analysis, as the minimum 12w-DCR threshold of 10 out of 25 patients required for the first step was not reached. From 06/03/2017 to 18/01/2021, 53 out of 112 patients were enrolled. Median follow-up was 22.6 months (range: 1.4-60.4). The 12w-DCR was 39.1 % in the FOLFIRI arm and 28.0 % in the CAPTEM arm. In the FOLFIRI subgroup the 12-months OS rate was 28.4 % (95 % CI: 12.7-46.5) while in the CAPTEM subgroup it was 32.4 % (95 % CI: 14.9-51.3). The most common G3-G4 side effects were neutropenia (n = 5, 18.5 %) and anemia (n = 2, 7.4 %) for FOLFIRI and G3-G4 thrombocytopenia (n = 2, 8.0 %), G4 nausea/vomiting (n = 1, 4.0 %) for CAPTEM. Three microRNAs emerged as NEC independent predictors. High expression values were found to be significantly associated with decreased PFS and OS.

CONCLUSION

The safety profile of FOLFIRI and CAPTEM was manageable. FOLFIRI and CAPTEM chemotherapy showed comparable activity in the second-line setting after progression on etoposide/platinum.

CLINICALTRIALS

GOV IDENTIFIER

NCT03387592.

Pure large-cell neuroendocrine carcinoma of the ovary with a somatic BRCA1 mutation: The first reported case and the review of the literature

Pure large-cell neuroendocrine carcinomas of the ovary are extremely rare, so there is a lack of molecular information on this type of cancer. Herein, we presented a pure primary large-cell neuroendocrine carcinomas of the ovary in a 72-year-old female with a pathogenic somatic mutation at the c.5332+1g>a splice site of the BRCA1 gene and with no TP53 mutation. She was uneventful 32 months after the operation and chemotherapies. To the best of our knowledge, this is the first report of a BRCA1 somatic mutation in the ovary large-cell neuroendocrine carcinomas. Testing BRCA1/2 mutations in patients with large ovarian cell neuroendocrine carcinomas might provide an opportunity for their future target treatments. It would expand our understanding.

Mutational analysis of pulmonary large cell neuroendocrine carcinoma: APC gene mutations identify a good prognostic factor

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a highly aggressive neoplasm with biological heterogeneity. Mutations in multiple genes have been identified in LCNEC. However, associations between gene alterations, histopathological characteristics, and prognosis remain ambiguous. Here, we investigated the clinicopathologic, immunohistochemical, and genomic characteristics of 19 patients with LCNEC and 9 patients with atypical carcinoid (AC). We revealed high mutation frequencies of TP53 (89.5 %), RB1 (42.1 %), APC (31.6 %), and MCL1 (31.6 %) in LCNEC, while genetic alterations were rarely found in AC. APC alterations mainly occurred to the exon 16 and were only identified in LCNEC with wild-type RB1. The 19 LCNEC were further subgrouped into APC wild-type (LCNEC-APCMT, 6/19) and APC-mutated (LCNEC-APCWT, 13/19) subgroups. In comparison with LCNEC-APCWT, LCNEC-APCMT displayed lower TMB (median: 12.64 vs 4.20, P = 0.045), and relatively mild cytologic atypia. In addition, LCNEC-APCMT distinguished itself from AC and LCNEC-APCWT by obviously downregulated expression of neuroendocrine markers (CD56 and Syn, P < 0.01) and significantly altered expression of genes downstream of APC (β-catenin migrating into the cytoplasm and nucleus, P < 0.001; c-Myc upregulating, P = 0.005). The OS of LCNEC-APCMT was numerically intermediate between AC and LCNEC-APCWT. We first proposed that APC alterations were common in LCNEC with wild-type RB1 and that LCNEC-APCMT was associated with lower TMB and better OS in comparison with LCNEC-APCWT.

Patient-derived tumoroid models of pulmonary large-cell neuroendocrine carcinoma: a promising tool for personalized medicine and developing novel therapeutic strategies

Pulmonary large-cell neuroendocrine carcinoma (LCNEC), a disease with poor prognosis, is classified as pulmonary high-grade neuroendocrine carcinoma, along with small-cell lung cancer. However, given its infrequent occurrence, only a limited number of preclinical models have been established. Here, we established three LCNEC tumoroids for long-term culture. Whole-exome sequencing revealed that these tumoroids inherited genetic mutations from their parental tumors; two were classified as small-cell carcinoma (S-LCNEC) and one as non-small cell carcinoma (N-LCNEC). Xenografts from these tumoroids in immunodeficient mice mimicked the pathology of the parent LCNEC, and one reproduced the mixed-tissue types of combined LCNEC with a component of adenocarcinoma. Drug sensitivity tests using these LCNEC tumoroids enabled the evaluation of therapeutic agent efficacy. Based on translational research, we found that a CDK4/6 inhibitor might be effective for N-LCNEC and that Aurora A kinase inhibitors might be suitable for S-LCNEC or LCNEC with MYC amplification. These results highlight the value of preclinical tumoroid models in understanding the pathogenesis of rare cancers and developing treatments. LCNEC showed a high success rate in tumoroid establishment, indicating its potential application in personalized medicine.

Prognostic scores in pulmonary large cell neuroendocrine carcinoma: A retrospective cohort study

Introduction

Pulmonary large cell neuroendocrine carcinoma (PLCNEC) is a rare but aggressive subtype of lung cancer with an incidence of approximately 3 %. Identifying effective prognostic indicators is crucial for guiding treatments. This study examined the relationship between inflammatory markers and PLCNEC patient overall survival (OS) and sought to determine their prognostic significance in PLCNEC.

Methods

Patients diagnosed with PLCNEC between 2007 and 2022 at the oncology center, were retrospectively included. Patients who underwent surgery were pathologically re-staged post-surgery. Potential prognostic parameters (neutrophil/lymphocyte ratio, platelet/lymphocyte ratio [PLR], panimmune inflammatory value, prognostic nutritional index and modified Glasgow prognostic score [mGPS]) were calculated at that time of diagnosis.

Results

Sixty patients were included. The median follow-up was 23 months. Thirty-eight patients initially diagnosed with early or locally advanced. The mGPS was identified as a poor prognostic factor that influenced disease free survival (DFS) fourfold (p = 0.03). All patients' median OS was 45 months. Evaluating factors affecting OS in all patients, statistically significant relationships were observed between OS and the prognostic nutritional index (p = 0.001), neutrophil/lymphocyte ratio (p = 0.03), platelet/lymphocyte ratio (p = 0.002), and pan-immunoinflammatory value (p = 0.005). Upon multivariate analysis, the platelet/lymphocyte ratio was identified as an independent poor prognostic factor for OS, increasing the mortality risk by 5.4 times (p = 0.002).

Conclusion

mGPS was significantly linked with prognosis in non-metastatic PLCNEC, with patients with higher mGPS exhibiting poorer long-term DFS. This finding contributes to the evolving understanding of PLCNEC. The multivariable predictive model we employed suggests that PLR is an independent predictor of OS at all stages. A lower PLR was correlated with worse overall survival. Thus, PLR can be a readily accessible and cost-effective prognostic factor in PLCNEC patients.

Prognostic implications of synaptophysin, CD56, thyroid transcription factor-1, and Ki-67 in pulmonary high-grade neuroendocrine carcinomas

BACKGROUND

The correlation between the expression of immunohistochemical markers and the clinicopathological characteristics of pulmonary high-grade neuroendocrine carcinomas (HGNEC) and its impact on the clinical outcomes of individuals with HGNEC has not yet been explored.

METHODS

This study enrolled patients diagnosed with HGNEC between April 2015 and July 2023. Based on the expression levels of synaptophysin (Syn), the neural cell adhesion molecule (CD56), thyroid transcription factor-1 (TTF-1), and Ki-67, a comprehensive analysis was conducted. This involved a comparison of clinicopathological characteristics, chemosensitivity, overall survival (OS), and progression-free survival (PFS). Furthermore, the study identified prognostic factors associated with patient survival through univariate and multivariate analyses.

RESULTS

Eighty-two patients were analyzed. Significant differences were identified in tumor stage (χ2 = 5.473, P = 0.019), lymphatic invasion (χ2 = 8.839, P = 0.003), and distant metastasis (χ2 = 5.473, P = 0.019), respectively, between the CD56 positive and negative groups. A significant difference in lymphatic invasion was observed (χ2 = 9.949, P = 0.002) between the CD56 positive and negative groups. A significant difference in vascular invasion was observed (χ2 = 5.106, P = 0.024) between the low and high Ki-67 groups. Compared to the Syn negative group, the Syn positive group had significantly shorter PFS (P = 0.006). Compared to the Syn negative group, the Syn positive group had significantly shorter OS (P = 0.004). The CD56 positive group also had significantly shorter OS than the CD56 negative group (P = 0.027). Univariate analysis revealed that tumor stage and Syn expression were associated with OS and PFS. Lymphatic invasion and CD56 expression were associated with OS. Multivariate analysis revealed that tumor stage was the strongest predictor of poor prognosis for OS (hazard ratio [HR] 0.551, 95 % confidence interval [CI] 0.328-0.927, P = 0.025) and PFS (HR 0.409, 95 % CI 0.247-0.676, P < 0.001).

CONCLUSIONS

Positive expression of Syn was associated with reduced PFS and OS, while positive CD56 expression was correlated with a shorter OS in HGNEC. The TNM stage was an independent risk factor that significantly influenced PFS and OS in patients with HGNEC. More studies are needed to make further progress in future treatment.

Real-World comprehensive genomic profiling data for diagnostic clarity in pulmonary Large-Cell neuroendocrine carcinoma

BACKGROUND

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is an uncommon subtype of lung cancer believed to represent a spectrum of tumors sharing characteristics of both small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). Other groups have proposed genomic LCNEC subtypes, including small cell-like, non-small cell-like, and carcinoid-like subtypes. The primary goal of this study was to better define the NSCLC-like subtype with comprehensive genomic profiling (CGP).

METHODS

An institutional database was queried to identify tissue specimens (TBx, N = 1,426) and liquid biopsies (LBx, N = 39) submitted for CGP during routine clinical care (8/2014 - 7/2023) with a disease ontology of LCNEC. TBx were profiled with FoundationOne® (F1) or F1CDx, using hybrid-capture technology to detect genomic alterations (GAs).

RESULTS

1,426 LCNEC samples were genomically profiled. The presence of RB1 and TP53 genomic alterations (GAs) were used to define a SCLC-like subtype (n = 557). A carcinoid-like group was defined by the presence of MEN1 mutation in the absence of TP53 GAs (n = 25). The remaining 844 samples were compared to the SCLC-like group and GAs enriched relative to the SCLC-like samples with a false discovery rate (FDR) < 0.0001 were used to define a NSCLC-like group. These NSCLC-like subtype-defining GAs included SMARCA4, KRAS, FGF3/4/19, STK11, CDKN2A/B, MTAP, and CCND1. Under this schema, 530 samples were classified as NSCLC-like and 314 remained unclassified.

CONCLUSIONS

Large-scale CGP can better characterize biologically distinct molecular subtypes in LCNEC. Further studies to define how these molecular subtypes may help inform treatment decisions in this complex and challenging malignancy are warranted.

The outcomes of different regimens depend on the molecular subtypes of pulmonary large-cell neuroendocrine carcinoma: A retrospective study in China

BACKGROUND

The optimal systemic treatment for pulmonary large-cell neuroendocrine carcinoma (LCNEC) remains controversial, and recent advances in LCNEC molecular subtype classification have provided potential strategies for assisting in treatment decisions. Our study aimed to investigate the impact of treatment regimens, molecular subtypes and their concordance on clinical outcomes of patients diagnosed with LCNEC.

PATIENTS AND METHODS

All patients diagnosed with advanced pulmonary LCNEC in Peking Union Medical College Hospital (PUMCH) between January 2000 and October 2021 were enrolled in this retrospective study. The tumor samples were collected and sequenced using a tumor-specific gene panel, while clinical information was retrieved from the medical records system. The survival and therapeutic response were analyzed and compared between different subgroups classified by treatment regimen (SCLC or NSCLC-based), molecular subtype (type I or II) or the combination.

RESULTS

In univariate subgroup analysis categorized only by treatment regimen or molecular subtype, there were no differences identified in DCR, ORR, PFS, or OS. Nevertheless, the group with consistent treatment regimen and molecular subtype exhibited significantly longer OS than that of the inconsistent group (median OS 37.7 vs. 8.3 months; p = 0.046). Particularly, the OS of patients with type II LCNEC treated with SCLC-based regimen was significantly prolonged than that of others (median 37.7 vs. 10.5 months; p = 0.039).

CONCLUSIONS

Collectively, our study revealed the clinical outcomes of different treatment regimens for LCNEC patients highly depend on their molecular subtypes, highlighting the need for sequencing-guided therapy.

Pathologic diagnosis of lung cancer - recent developments

PURPOSE OF REVIEW

Diagnosis of lung cancer has previously been based on the evaluation of resection specimen. However, approximately 80% of lung cancers are diagnosed in stage IV. Targeted therapy has changed the practice of pathology. Diagnosis is usually based on small biopsies or even needle aspirations. Subtyping is important, as a molecular classification has to be added.

RECENT FINDINGS

Molecular analysis has to be done in adenocarcinomas and on some of the rarer carcinoma types. Molecular analysis of squamous cell carcinomas should be done in never or former smokers, as they might present with targetable oncogenes. The same applies for adenosquamous carcinomas. Both high-grade neuroendocrine carcinomas should be subtyped. These subtypes might become relevant for new treatment options, currently investigated. Subtyping is done by immunohistochemistry with antibodies for ASCL1, NeuroD1, and POU2F3. In carcinoids, molecular investigation can better define cases with a higher risk of recurrence and metastasis.

SUMMARY

Diagnosis of lung cancer is most often done on small biopsies or cytological preparations. Only a minimal number of tissues or cellular material is used for diagnosis. A considerable portion is reserved for molecular analysis. Molecular investigation is important in adenocarcinomas, but also for other rare tumor types.

Updates on lung neuroendocrine neoplasm classification

Lung neuroendocrine neoplasms (NENs) are a heterogeneous group of pulmonary neoplasms showing different morphological patterns and clinical and biological characteristics. The World Health Organisation (WHO) classification of lung NENs has been recently updated as part of the broader attempt to uniform the classification of NENs. This much-needed update has come at a time when insights from seminal molecular characterisation studies revolutionised our understanding of the biological and pathological architecture of lung NENs, paving the way for the development of novel diagnostic techniques, prognostic factors and therapeutic approaches. In this challenging and rapidly evolving landscape, the relevance of the 2021 WHO classification has been recently questioned, particularly in terms of its morphology-orientated approach and its prognostic implications. Here, we provide a state-of-the-art review on the contemporary understanding of pulmonary NEN morphology and the potential contribution of artificial intelligence, the advances in NEN molecular profiling with their impact on the classification system and, finally, the key current and upcoming prognostic factors.

Exploring the molecular features and genetic prognostic factors of pulmonary high-grade neuroendocrine carcinomas

Molecular research on large-cell neuroendocrine carcinoma (LCNEC) and small-cell lung cancer (SCLC) has progressed significantly. However, there are still fewer molecular markers related to prognostic/therapeutic strategies for these conditions compared to those for adenocarcinoma. We therefore investigated the molecular characteristics of neuroendocrine carcinomas (NECs). We enrolled patients surgically diagnosed with NECs between 2011 and 2019, with complete follow-up records. All were analyzed using whole exome sequencing and p53/Rb immunohistochemistry (IHC). A total of 92 cases, comprising 45 pure SCLC, 15 combined SCLC, 27 pure LCNEC, and 5 combined LCNEC, were included. TP53 (78.3%) and RB1 (34.8%) were the most common molecular alterations, followed by KMT2D, LRP1B, FAT3, NCOR2, SPTA1, and NOTCH1. The mutation frequency for EGFR was 10.9%. Sixteen patients with LCNEC who had TP53/RB1 co-alterations were SCLC-like, while the remaining were NSCLC-like. There was no statistically significant difference between the groups regarding overall survival (OS; p = 0.458) and progression-free survival (PFS; p = 0.157). The frequency of the loss of Rb expression by IHC in SCLC-like LCNEC was 100%. Significant pathway alterations unique to SCLC included Notch and AMPK, while HIF-1 was enriched exclusively in LCNEC. NCOR2 mutation was linked to worse OS (p = 0.029) and PFS (p = 0.015), while wild-type SPTA1 was associated with poor PFS (p = 0.018). IHC for Rb was reliable for predicting LCNEC molecular subtypes, indicating its clinical value. NCOR2 and SPTA1 alterations were identified as prognostic factors that may provide therapeutic targets for patients with NEC.

BRAF V600E-mutated large cell neuroendocrine carcinoma responding to targeted therapy: a case report and review of the literature

Large cell neuroendocrine carcinoma (LCNEC) is a rare and aggressive high-grade neuroendocrine tumor, commonly arising in the lung or in the gastrointestinal tract, with a frequent proportion of unknown primary origin (20%). In the metastatic setting, platinum-based or fluoropyrimidine-based chemotherapeutic regimens are as considered the first-line treatment, despite the limited duration of response. To date, the prognosis of advanced high-grade neuroendocrine carcinoma remains poor, suggesting the need to explore new treatment strategies in this orphan tumor. The evolving molecular landscape of LCNEC, not yet been completely defined, could explain the heterogeneous response to different chemotherapeutic regimens and suggest that treatment strategy could be driven by molecular features. v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutations, well described in melanoma, thyroid cancer, colon cancer and lung adenocarcinoma, account for approximately 2% of cases in lung LCNEC. Here, we describe the case of a patient with a BRAF V600E-mutated LCNEC of unknown primary origin who partially responded to BRAF/mitogen-activated protein kinase kinase inhibitors after standard treatment. Additionally, BRAF V600E circulating tumor DNA was used to monitor disease response. Thereafter, we reviewed the available literature about the role of targeted therapy in high-grade neuroendocrine neoplasms to provide insight for future research to identify patients with driver oncogenic mutations, who can potentially benefit from target therapy.

Pulmonary large cell neuroendocrine carcinoma (LCNEC): a population-based study addressing recent molecular-genetic advances and emerging therapeutic approaches

BACKGROUND

Large cell neuroendocrine carcinoma (LCNEC) of the lung is a rare, aggressive cancer most commonly found in the lungs but not exclusively, with a worse prognosis than non-small cell lung carcinomas. Currently, LCNEC patients are treated using small cell and non-small cell protocols. This study aims to use the SEER database to identify demographic, clinical, pathological, and therapeutic factors affecting the prognosis and survival of patients with LCNEC of the lung.

METHODS

Demographic, clinical, and management data of patients with lung LCNEC were extracted from the SEER database for the period 2000-2018.

RESULTS

In the USA, LCNEC has a higher incidence in elderly white men: M:F ratio = 1.2:1, Caucasian: 83.3%, mean age: 67 ± 10.2 years. The most common treatment modality was chemotherapy only: 29.2%, followed by surgery: 21.5% (but in this group the statuses of chemotherapy were unknown), and combination surgery/chemotherapy: 8.8%. The overall and cause-specific 5-year survival was 17.5% (95% CI 16.3-18.8) and 21.9% (95% CI 20.5-23.4), respectively. By treatment, the best 5-year survival was for surgery alone (48%), followed by multimodality therapy (chemo + surgery + radiation) at 35% (95% CI 27-43). Age > 60 years, male gender, size > 7 cm, and nodal and liver metastasis were independent risk factors associated with increased mortality.

CONCLUSION

Lung LCNEC is an aggressive neoplasm most common in older white males that presents at an advanced stage despite small primary tumors. Most patients die within 2 years. The best predictor of survival is surgery with chemotherapy. Given its dismal prognosis, new treatment guidelines are needed for this aggressive cancer.

Equivalent Survival between Gastric Large-Cell Neuroendocrine Carcinoma and Gastric Small-Cell Neuroendocrine Carcinoma

BACKGROUND

According to the 2019 World Health Organization (WHO) classification of gastric neuroendocrine neoplasms, gastric neuroendocrine carcinoma (GNEC) can be further divided into gastric large-cell neuroendocrine carcinoma (GLNEC) and gastric small-cell neuroendocrine carcinoma (GSNEC). Whether the prognoses of the two types have a discrepancy has long been disputed.

METHOD

We collected patients diagnosed with GLNEC or GSNEC in the National Cancer Center of China between January 2000 and December 2020. The characteristics and survival outcomes were compared between the two groups. We further verified our conclusion using the SEER dataset.

RESULTS

A total of 114 GNEC patients, including 82 patients with GLNEC and 32 patients with GSNEC, have completed treatment in our hospital. Clinicopathologic differences were not observed between patients with GSNEC and GLNEC concerning the sex, age, body mass index, Charlson Comorbidity Index, tumor location, tumor size, stage, treatment received, the expression of neuroendocrine markers (CD56, Chromogranin A, synaptophysin), and score on the Ki-67 index. The 1-year, 3-year, and 5-year overall survival rates of GLNEC and GSNEC were 89.0%, 60.5%, and 52.4%, and 93.8%, 56.3%, and 52.7%, which showed no statistically significant differences. This result was confirmed further by using the SEER dataset after the inverse probability of treatment weighting.

CONCLUSIONS

Although with different cell morphology, the comparison of prognosis between the GLNEC and GSNEC has no significant statistical difference.

Updates in histopathological classification and tissue biomarkers of digestive neuroendocrine neoplasms: What the clinician should know

Histopathological classifications of neuroendocrine neoplasms (NEN) change regularly and the latest WHO classification published in 2022, which concerns all NEN in the body, attempts to standardize classifications in the different locations. Differentiation and proliferation mainly assessed by Ki-67 index are still the cornerstone of those classifications. However, many markers are now used for diagnostic (to check neuroendocrine differentiation, to identify the site of origin of a metastasis, to help separating high-grade neuroendocrine tumors/NET and neuroendocrine carcinoma/NEC), prognostic or theranostic purposes. NENs are often heterogeneous and this can lead to difficulties in classifications, biomarker and prognostic assessment. These different points are discussed successively in this review, insisting especially on the frequent digestive, gastro-entero-pancreatic (GEP) localizations.

Combined large cell neuroendocrine carcinoma, lung adenocarcinoma, and squamous cell carcinoma: a case report and review of the literature

BACKGROUND

Combined large cell neuroendocrine carcinoma (C-LCNEC) has a poor prognosis and there is no consensus about the treatment regimen for both LCNEC and C-LCNEC patients.

CASE PRESENTATION

The patient was a 47-year-old female who received surgical resection. The postoperative histology and staging of the tumor suggested C-LCNEC with adenocarcinoma and squamous cell carcinoma and T2aN0M0 stage IB. Next-generation sequencing test showed KIF5B/RET fusion mutation without EGFR, ALK, RB1, and TP53 alterations. Adjuvant chemotherapy with 4-cycle docetaxel plus carboplatin was given and brain metastasis occurred after 10 months.

CONCLUSIONS

C-LCNEC with adenocarcinoma and squamous cell carcinoma is rare and highly aggressive cancer. Surgical resection and adjuvant chemotherapy with SCLC regimen may improve the disease-free survival and overall survival. The accumulation of similar cases will clarify the profile and management of the disease.

Systemic treatment for neuroendocrine non-small cell lung carcinoma: A cases series and a systematic review of the literature

INTRODUCTION

Neuroendocrine lung cancer constitutes a continuum from carcinoid tumours (CT) to large cell neuroendocrine (LCNEC) and small-cell carcinomas (SCLC). Except for SCLC, there is no consensual agreement on systemic therapy. The aim of this study is to review our clinical experience among patients with CT and LCNEC in the light of a systematic review of the literature.

METHODS

A retrospective study of all patients with CT and LCNEC receiving a systemic therapy at Institut Jules Bordet and Erasme Hospital between 01/01/2000-31/12/2020. A systematic review of the literature was performed in Ovid Medline.

RESULTS

53 patients (21 CT and 32 LCNEC) were included. Despite limited response rates, patients with CT receiving a "carcinoid-like" 1st-line regimen (somatostatin analogues (SSA), everolimus, peptide receptor radionuclide therapy (PRRT)) had a numerically longer survival compared to those receiving other type of regimens (median 51.4 vs 18.6 months, respectively; p = 0.17). We observed a similar survival between 1st line "SCLC-like" vs "non-small cell lung cancer (NSCLC)-like" schemes in LCNEC (median 11.2 vs 12.6 months, respectively; p = 0.46). The systematic review identified 23 studies (12 prospective, 15 and 8 for CT and LCNEC respectively). For CT, everolimus and SSA led to prolonged disease control with an acceptable toxicity profile, while higher response rates but lower tolerance were associated with PRRT and chemotherapy regimens including oxaliplatine and dacarbazine. For LCNEC, no difference emerged when comparing "SCLC-like" and "NSCLC-like" regimens considering response rate, progression-free or overall survival.

CONCLUSIONS

SSA, everolimus and PRRT present a good therapeutic index for CT, while the role of chemotherapy remains limited to aggressive and rapidly evolving CT. The best type of chemotherapy regimen remains an open question in LCNEC.

Spotlight on Small-Cell Lung Cancer and Other Lung Neuroendocrine Neoplasms

Lung neuroendocrine neoplasms (NENs) encompass a spectrum of neoplasms that are subdivided into the well-differentiated neuroendocrine tumors comprising the low- and intermediate-grade typical and atypical carcinoids, respectively, and the poorly differentiated, high-grade neuroendocrine carcinomas including large-cell neuroendocrine carcinomas and small-cell lung carcinoma (SCLC). Here, we review the current morphological and molecular classifications of the NENs on the basis of the updated WHO Classification of Thoracic Tumors and discuss the emerging subclassifications on the basis of molecular profiling and the potential therapeutic implications. We focus on the efforts in subtyping SCLC, a particularly aggressive tumor with few treatment options, and the recent advances in therapy with the adoption of immune checkpoint inhibitors in the frontline setting for patients with extensive-stage SCLC. We further highlight the promising immunotherapy strategies in SCLC that are currently under investigation.

Incidence, survival comparison, and novel prognostic evaluation approaches for stage iii-iv pulmonary large cell neuroendocrine carcinoma and small cell lung cancer

BACKGROUND

Pulmonary large cell neuroendocrine carcinoma (LCNEC) and small cell lung cancer (SCLC) are two types of high-grade neuroendocrine carcinomas of the lung with poor prognosis. LCNEC has not been thoroughly studied due to its rarity, data are also lacking regarding the survival comparison and prognosis analysis of patients with locally advanced or metastatic LCNEC and SCLC.

METHODS

Data of patients with LCNEC, SCLC, and other NSCLC who were diagnosed from 1975 to 2019 were extracted from the Surveillance, Epidemiology and End Results (SEER) database to estimate incidence. Those in stage III-IV and being diagnosed from 2010 to 2015 were utilized further to investigate their clinical characteristics and prognosis. Propensity score matching (PSM) analyses at a ratio of 1:2 was used to compare their survival outcomes. Nomograms of LCNEC and SCLC were established with internal validation, and the nomogram of SCLC was externally validated by 349 patients diagnosed in Cancer hospital, Chinese Academy of Medical Sciences & Peking Union Medical College from January 1, 2012 to December 31, 2018.

RESULTS

The incidence of LCNEC has been increasing in recent decades, meanwhile that of SCLC and other types of NSCLC were decreasing. A total of 91,635 lung cancer patients, including 785 with LCNEC, 15,776 with SCLC, and 75,074 with other NSCLC were enrolled for further analysis. The survival of stage III-IV LCNEC resembles that of SCLC, and significantly worse than other types of NSCLC before and after PSM analysis. In pretreatment prognostic analysis, age, T stage, N stage, M stage, bone metastasis, liver metastasis, and brain metastasis were found to be associated with the survival of both LCNEC and SCLC, besides sex, bilaterality, and lung metastasis were additional prognostic factors for SCLC. Two nomograms and convenient online tools respectively for LCNEC and SCLC were established accordingly with favorable predicting accuracy of < 1-year, < 2-year, < 3-year survival probabilities. In external validation of the SCLC nomogram with a Chinese cohort, the AUCs of 1-year, 2-year and 3-year ROC were 0.652, 0.669, and 0.750, respectively. All the results of 1-, 2-, 3- year variable-dependent ROC curves verified the superior prognostic value of our nomograms for LCNEC and SCLC over the traditional T/N/M staging system.

CONCLUSIONS

Based on large sample-based cohort, we compared the epidemiological trends and survival outcomes between locally advanced or metastatic LCNEC, SCLC, and other NSCLC. Furthermore, two prognostic evaluation approaches respectively for LCNEC and SCLC might present as practical tools for clinicians to predict the survival outcome of these patients and facilitate risk stratification.

Neuroendocrine Neoplasms: Genetics and Epigenetics

Neuroendocrine neoplasms (NENs) are a group of rare, heterogeneous tumors of neuroendocrine cell origin, affecting a range of different organs. The clinical management of NENs poses significant challenges, as tumors are often diagnosed at an advanced stage where overall survival remains poor with current treatment regimens. In addition, a host of complex and often unique molecular changes underpin the pathobiology of each NEN subtype. Exploitation of the unique genetic and epigenetic signatures driving each NEN subtype provides an opportunity to enhance the diagnosis, treatment, and monitoring of NEN in an emerging era of individualized medicine.

Expression of p53 and Rb reveal subtypes of gastric neuroendocrine carcinoma with distinct prognosis

Gastric neuroendocrine carcinoma (NEC) is a rare tumor with a poor prognosis. Due to its rarity and disparity in prevalence across populations, there is limited data on gastric NEC. TP53 and RB1 genetic alterations or expression were reported for predictive value in neuroendocrine neoplasm and classification in pulmonary large cell NEC. This study investigated the genetic alteration and protein expression of TP53 and RB1 in gastric NEC. Thirty-nine patients were categorized as type A and B subtypes by p53 and Rb expression. Patients with concurrent abnormal p53 and Rb expression were defined as the type A group, and the remainder were defined as the type B group. Significant differences in TNM stages, tumor size, and lymph node metastasis were observed between the two subtypes. Type A characteristic is an independent predictor for worse overall survival (HR: 3.27; 95% CI: 1.12-9.58; p = .022). We further evaluated and compared immunotherapy-related markers, including PD-L1 expression, CD8 T cell infiltration, tumor mutation burden, and microsatellite instability in these two subtypes, whereas no significant differences were detected.

Pulmonary neuroendocrine tumors: study of 266 cases focusing on clinicopathological characteristics, immunophenotype, and prognosis

OBJECTIVE

Pulmonary neuroendocrine tumors (PNETs) consist of small-cell lung cancer (SCLC), large-cell neuroendocrine carcinoma (LCNEC), typical carcinoid (TC), and atypical carcinoid (AC). We aimed to analyze the immunophenotypic, metastatic, and prognostic risk factors for PNETs.

MATERIALS AND METHODS

A total of 266 patients with PNETs were enrolled, including 219 patients with SCLC, 18 patients with LCNEC, 11 patients with TC, and 18 patients with AC. Clinicopathological characteristics and immunophenotypes were compared among the subtypes of PNETs. Risk factors for metastasis, progression-free survival (PFS), and overall survival (OS) were analyzed.

RESULTS

Thyroid transcription factor-1 (TTF-1) and the Ki-67 index were significantly different among subtypes of PNETs (all P < 0.05). Smoking (OR, 2.633; P = 0.031), high pretreatment carcinoembryonic antigen (CEA > 5 ng/ml: OR, 3.084; P = 0.014), and poorly differentiated pathotypes (P = 0.001) were independent risk factors for lymph-node metastasis. Smoking (OR, 2.071; P = 0.027) and high pretreatment CEA (OR, 2.260; P = 0.007) were independent risk factors for distant metastasis. Results of the multivariate Cox regression model showed pretreatment CEA (HR, 1.674; P = 0.008) and lymphocyte-monocyte ratio (LMR) (HR = 0.478, P = 0.007) were significantly associated with PFS; BMI (P = 0.031), lymph-node metastasis (HR = 4.534, P = 0.001), poorly differentiated pathotypes (P = 0.015), platelet-lymphocyte ratio (PLR) (HR = 2.305, P = 0.004), and LMR (HR = 0.524, P = 0.045) were significantly associated with OS.

CONCLUSIONS

PNETs are a group of highly heterogeneous tumors with different clinical manifestations, pathological features, and prognoses. Knowing clinicopathological characteristics and immunophenotypes of PNETs is significant for diagnosis. Pretreatment PLR, LMR, and CEA have certain value in the prognosis of PNETs.

All Together Now: Standardization of Nomenclature for Neuroendocrine Neoplasms across Multiple Organs

Neuroendocrine neoplasms (NENs) span virtually all organ systems and exhibit a broad spectrum of behavior, from indolent to highly aggressive. Historically, nomenclature and grading practices have varied widely across, and even within, organ systems. However, certain core features are recapitulated across anatomic sites, including characteristic morphology and the crucial role of proliferative activity in prognostication. A recent emphasis on unifying themes has driven an increasingly standardized approach to NEN classification, as delineated in the World Health Organization's Classification of Tumours series. Here, we review recent developments in NEN classification, with a focus on NENs of the pancreas and lungs.

Whole-genome characterization of large-cell lung carcinoma: A comparative analysis based on the histological classification

Background: According to the 2015 World Health Organization classification, large cell neuroendocrine carcinoma (LCNEC) was isolated from Large-cell lung cancer (LCLC) tumors, which constitutes 2%-3% of non-small cell lung cancer (NSCLC). However, LCLC tumors are still fairly vaguely defined at the molecular level compared to other subgroups. Materials and Methods: In this study, whole-genome sequencing (WGS) was performed on 23 LCLC and 15 LCNEC tumor specimens. Meanwhile, data from the TCGA (586 LUADs and 511 LUSCs) and U Cologne (120 SCLCs) were analyzed and compared. Results: The most common driver mutations were found in TP53 (13/23, 57%), FAM135B (8/23, 35%) and FAT3 (7/23, 30%) in LCLC, while their counterparts in LCNEC were TP53 (13/15, 87%), LRP1B (6/15, 40%) and FAT1 (6/15, 40%). Notably, FAM135B mutations only occurred in LCLC (P = 0.013). Cosmic signature analysis revealed widespread defective DNA mismatch repair and tobacco-induced mutations in both LCLC and LCNEC. Additionally, LCNEC had a higher incidence of chromosomal copy number variations (CNVs) and structural variations (SVs) compared with LCLC, although the differences were not statistically significant. Particularly, chromothripsis SVs was significantly associated with CNVs. Furthermore, mutational landscape of different subtypes indicated differences between subtypes, and there seems to be more commonalty between our cohort and SCLC than with other subtypes. SMARCA4 mutations may be specific driver gene alteration in our cohort. Conclusion: Our results support that LCLC and LCNEC tumors follow distinct tumorigenic pathways. To our knowledge, this is the first genome-wide profiling comparison of LCLC and LCNEC.

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.

Differential response in patients with large cell neuroendocrine carcinoma of the lung to initial therapy: A case series

BACKGROUND

Large cell neuroendocrine tumors of the lung (LCNEC) are rare. Chemotherapy with the small cell lung carcinoma (SCLC) regimen is the most appropriate treatment for LCNEC. However, there is evidence that the non-small cell lung cancer regimen is also effective in some reported cases. Due to the differences in response to LCNEC treatment, a standard of care for LCNEC has not been established.

CASES

The clinical records of nine patients with LCNEC who were treated with anticancer drugs based on an SCLC regimen from March 2016 to March 2022 were retrospectively reviewed. The patients who responded to treatment after one cycle of systemic chemotherapy were compared to those who did not respond. All patients in the responder group had a performance status (PS) of 0 or 1. However, 5 of the 6 patients in the non-responder group had a PS of 2 or 3, indicating that many patients were in poor general condition. Although patients with multiple metastases to more than one organ prior to treatment were not identified in the responder group, five of these patients were in the non-responder group. In the non-responder group, all patients discontinued treatment due to deterioration of general condition during first-line treatment. Thus, none of them were able to start the second-line treatment.

CONCLUSION

The results of this study may suggest that early diagnosis and initiation of treatment before multiple organ metastasis development and PS decline may have clinical implications that could lead to improved treatment response in patients with LCNEC.

To Rb or Not to Rb: Uncovering Unique Subsets of Small Cell Lung Carcinoma

The use of IHC as a surrogate for specific underlying genomic alterations has allowed for increasingly comprehensive and accurate diagnosis of small cell lung carcinoma (SCLC). This is especially relevant in light of the increasing recognition of the biologic heterogeneity of this aggressive and difficult-to-treat lung tumor. Integrated genomic and IHC profiling of Rb status in SCLC yields new diagnostic insights and has translational implications. See related article by Febres-Aldana et al., p. 4702.

Pulmonary Large Cell Neuroendocrine Carcinoma

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a rare subtype of malignant pulmonary tumor. The incidence rate of LCNEC was reported to be 0.3%–3% in lung cancers. Although LCNEC is classified as non-small cell lung cancer (NSCLC), it is more aggressive and malignant than other NSCLC, and its biological behavior is similar to that of small cell lung cancer (SCLC). Most of the LCNEC patients are elderly smoking male and the clinical manifestations are not specific. The imaging manifestations of the tumors are often located in the periphery and the upper lobes, and the enlargement of mediastinal or hilar lymph nodes is common. The diagnosis is mainly based on pathology by the histological features and immunohistochemistry (IHC). Specific neuroendocrine markers such as chromogranin A (CgA), synaptophysin (Syn) and CD56 are usually diffusely positive in LCNEC, and found that insulinoma-associated protein (INSM1) and high rate of Ki-67 are helpful for diagnosis. More differential diagnoses also increase the difficulty of correctly diagnosing LCNEC. The rise of LCNEC molecular typing in recent years may be helpful for diagnosis and subsequent treatment. This review focuses on the epidemiological features, imaging studies, pathology, diagnosis, treatment, and prognosis of LCNEC.

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.

Targeting ALK in Neuroendocrine Tumors of the Lung

Background

Anaplastic lymphoma kinase (ALK) rearrangements are known oncogenic drivers in non-small cell lung cancer (NSCLC). Few case reports described the occurrence of such rearrangements in large cell neuroendocrine carcinomas (LCNECs) of the lung without information on clinical responses to ALK tyrosine kinase inhibitors (TKIs) in these cases. Currently, neuroendocrine tumors of the lungs are not screened for ALK rearrangements.

Methods

To illustrate the clinical impact of molecular characterization in LCNECs, we report the disease course in three patients with ALK-rearranged metastatic LCNEC from our clinical routine, as well as their treatment response to ALK TKIs (index cases). To gain insight into the prevalence of ALK rearrangements in neuroendocrine tumors of the lung, we analyzed a retrospective cohort of 436 tumor biopsies including LCNEC (n = 61), small cell lung cancer (SCLC) (n = 206), typical (n = 91) and atypical (n = 69) carcinoids, and mixed histology (n = 9) for the presence of ALK rearrangements using a sequential diagnostic algorithm. ALK immunohistochemistry (IHC) was evaluable in 362 cases; fluorescence in situ hybridization (FISH) was evaluable in 28 out of the 35 IHC-positive cases, followed by next-generation sequencing (NGS) that was available in 12 cases.

Results

Within the retrospective cohort, ALK IHC was positive in 35 out of 362 (9.7%) evaluable samples. FISH was positive in 3 out of the 28 (10.7%) evaluable cases: 2 with atypical carcinoids and 1 with LCNEC. Additionally, the 3 index cases showed positive ALK IHC, which was confirmed by NGS. Within the retrospective cohort, NGS confirmed the presence of an ALK genomic rearrangement in one FISH-positive atypical carcinoid where material was sufficient for sequencing. Two out of three patients with metastatic ALK-rearranged LCNEC received up-front treatment with the ALK TKI alectinib and showed rapid tumor response at all metastatic sites, including multiple brain metastases.

Conclusions

ALK rearrangements represent rare but targetable oncogenic driver alterations in LCNEC. Contrarily to NSCLC, the detection of ALK rearrangements in neuroendocrine tumors of the lung is challenging, since ALK IHC can lead to false-positive results and therefore needs confirmation by FISH or NGS. Up-front comprehensive molecular profiling with NGS should be performed in metastatic LCNEC in order not to miss actionable genomic alterations.

Neuronal survival factor VGF promotes chemoresistance and predicts poor prognosis in lung cancers with neuroendocrine feature

High-grade neuroendocrine tumors (NETs) of the lung consist of small-cell lung cancer (SCLC) and large-cell neuroendocrine carcinoma (LCNEC). Both exhibit aggressive malignancy with poor prognosis. The transformation of lung adenocarcinoma (ADC) to SCLC or LCNEC also contributes to acquired resistance to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs). Despite initially being responsive to chemotherapy, high-grade NET patients inevitably develop drug resistance; thus, novel therapeutic targets are urgently needed for these patients. This study reported that VGF (nerve growth factor inducible), a factor mainly expressed in neurons during neural development, is highly expressed in SCLC and LCNEC as well as in a subset of ADCs, whereas targeting VGF attenuates cancer cell growth and tumor formation. High VGF expression was associated with advanced stage SCLC and predicted poor prognosis in lung ADC. In addition, EGFR-TKI selection enriched VGF expression in TKI-resistant ADC under epigenetic control. The VGF locus possessed the HDAC1 binding site, and treatment of ADC cells with the HDAC1 inhibitor induced VGF expression. High VGF expression was associated with chemoresistance, and silencing VGF induced BMF and BCL2L11 expression and rendered lung cancer cells sensitive to chemotherapy drugs. These findings suggested the potential of VGF as a prognostic factor and therapeutic target in lung cancers with neuroendocrine feature. This article is protected by copyright. All rights reserved.

Diagnostic criteria and evolving molecular characterization of pulmonary neuroendocrine carcinomas

Neuroendocrine carcinomas of the lung are currently classified into two categories: small cell lung carcinoma and large cell neuroendocrine carcinoma. Diagnostic criteria for small cell- and large cell neuroendocrine carcinoma are based solely on tumor morphology; however, overlap in histologic and immunophenotypic features between the two types of carcinoma can potentially make their classification challenging. Accurate diagnosis of pulmonary neuroendocrine carcinomas is paramount for patient management, as clinical course and treatment differ between small cell and large cell neuroendocrine carcinoma. Molecular-genetic, transcriptomic, and proteomic data published over the past decade suggest that small cell and large cell neuroendocrine carcinomas are not homogeneous categories but rather comprise multiple groups of distinctive malignancies. Nuances in the susceptibility of small cell lung carcinoma subtypes to different chemotherapeutic regimens and the discovery of targetable mutations in large cell neuroendocrine carcinoma suggest that classification and treatment of neuroendocrine carcinomas may be informed by ancillary molecular and protein expression testing going forward. This review summarizes current diagnostic criteria, prognostic and predictive correlates of classification, and evidence of previously unrecognized subtypes of small cell and large cell neuroendocrine carcinoma.

Endostar plus pembrolizumab combined with a platinum-based dual chemotherapy regime for advanced pulmonary large-cell neuroendocrine carcinoma as a first-line treatment: A case report

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a rare and highly aggressive cancer with a very poor prognosis. The proper treatment decision and possible prognosis outcome for advanced LCNEC is always an enormous challenge due to its scarcity. Here, we presented a 59-year-old male patient with advanced LCNEC with a non-neuroendocrine immunophenotype who received endostar plus pembrolizumab combined with a platinum-based dual chemotherapy regime as a first-line treatment. At present, the patient’s condition is well controlled by medication only and has a progression-free survival of more than 2 years. Adverse effects recorded for this patient during treatment courses include nausea, vomiting, II–III quality bone marrow toxicity, and PD-1 blockage-related hypothyroidism. This case report discussed the feasibility of immunotherapy, anti-angiogenesis agents, and chemotherapy as a first-line therapy in advanced LCNEC.

Mixed large and small cell neuroendocrine carcinoma of the stomach: A case report and review of literature

BACKGROUND

Gastric neuroendocrine carcinoma (GNEC) is a rare histological subtype of gastric cancer, which is categorized into small cell and large cell neuroendocrine carcinomas. It is characterized by strong invasiveness and poor prognosis. Mixed large and small cell neuroendocrine carcinoma (L/SCNEC) is an extremely rare pathological type of gastric cancer, and there have been no reports on this situation until now.

CASE SUMMARY

Herein, we first present a 57-year-old patient diagnosed with L/SCNEC of the stomach. A 57-year-old Chinese male presented with epigastric discomfort. Outpatient gastroscopic biopsy was performed, and pathological examination revealed that the cardia was invaded by adenocarcinoma. The patient underwent laparoscopic-assisted radical proximal subtotal gastrectomy and was diagnosed with L/SCNEC. He refused adjuvant treatment and was followed up every 3 mo. Eight months after the operation, the patient showed no evidence of local recurrence or distant metastasis.

CONCLUSION

We advocate conducting further genomic studies to explore the origin of gastric large cell and small cell neuroendocrine carcinoma and using different chemotherapy schemes according to large or small cell neuroendocrine carcinoma of the stomach for clinical research to clarify the heterogeneity of GNEC and improve the prognosis of patients with GNEC.

Case Report: Extensive Tumor Profiling in Primary Neuroendocrine Breast Cancer Cases as a Role Model for Personalized Treatment in Rare and Aggressive Cancer Types

Neuroendocrine breast cancer (NEBC) is a rare entity accounting for <0.1% of all breast carcinomas and <0.1% of all neuroendocrine carcinomas. In most cases treatment strategies in NEBC are empirical in absence of prospective trial data on NEBC cohorts. Herein, we present two case reports diagnosed with anaplastic and small cell NEBC. After initial therapies failed, comprehensive tumor profiling was applied, leading to individualized treatment options for both patients. In both patients, targetable alterations of the PI3K/AKT/mTOR pathway were found, including a PIK3CA mutation itself and an STK11 mutation that negatively regulates the mTOR complex. The epicrisis of the two patients exemplifies how to manage rare and difficult to treat cancers and how new diagnostic tools contribute to medical management.

Large Cell Neuroendocrine Carcinoma of the Skin/Conjunctiva: A Series of 6 Cases including 1 Combined Case With Squamous Cell Carcinoma

ABSTRACT

This study sought to reveal the clinicopathologic characteristics of large cell neuroendocrine carcinoma (LCNEC) of the skin/conjunctiva. The retrieved patients included 3 men and 3 women with a median age of 85 (63-95) years. All lesions occurred on the face, including the ears, with a median tumor size of 11.5 (7-65) mm. Lymph node metastasis was observed in 5 (83%) of 6 cases, and distant metastasis was noted in 2 (33%). One patient (17%) who had a 13-mm-sized tumor died of the tumor 13 months after excision. All tumors were mainly located in the dermis, and one of them also exhibited intraepithelial spreading. The cytology resembled that of an LCNEC in other organs. No adnexal differentiation was observed. Five cases were of the pure type, but one had a component of squamous cell carcinoma. Immunoreactivities for CAM5.2, CK7, CK19, BerEP4, epithelial membrane antigen, neuron-specific enolase, synaptophysin, c-KIT, GATA3, and bcl-2 were frequently present, but CK20, neurofilament, Merkel cell polyomavirus large T antigen, mammaglobin, estrogen receptor, HER2, and TTF1 were completely negative in all cases. Mutant-pattern immunostaining of p53, PTEN, and Rb was frequently observed. The Ki67 rate exceeded 70% in all cases. LCNEC of the skin/conjunctiva is a morphologically-defined group of primary cutaneous/conjunctival neuroendocrine neoplasm, although it may be heterogeneous similar to other-site LCNEC or Merkel cell carcinoma. This study highlighted the predominant location for the face, high metastatic and lethal potential, possible combination with other tumor components, and frequent mutant-type immunoexpressions of p53, PTEN, and Rb in this tumor group.

Diagnosis in Neuroendocrine Neoplasms: From Molecular Biology to Molecular Imaging

Simple Summary

Neuroendocrine neoplasms are a small group of malignancies with a diverse prognosis and behaviour. In order to offer an adequate treatment, physicians need to perform a proper diagnosis, staging and stratification. This review aims to help to integrate the information from pathology, immunohistochemistry, molecular biology and imaging to guide this process.

Abstract

Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumours with a diverse behaviour, biology and prognosis, whose incidence is gradually increasing. Their diagnosis is challenging and a multidisciplinary approach is often required. The combination of pathology, molecular biomarkers, and the use of novel imaging techniques leads to an accurate diagnosis and a better treatment approach. To determine the functionality of the tumour, somatostatin receptor expression, differentiation, and primary tumour origin are the main determining tumour-dependent factors to guide treatment, both in local and metastatic stages. Until recently, little was known about the biological behaviour of these tumours. However, in recent years, many advances have been achieved in the molecular characterization and diagnosis of NENs. The incorporation of novel radiotracer-based imaging techniques, such as ⁶⁸Gallium-DOTATATE PET-CT, has significantly increased diagnostic sensitivity, while introducing the theragnosis concept, offering new treatment strategies. Here, we will review current knowledge and novelties in the diagnosis of NENs, including molecular biology, pathology, and new radiotracers.

High mRNA expression of POU2F3 in small cell lung cancer cell lines predicts the effect of lurbinectedin

Background

Small cell lung cancer (SCLC) is a progressive disease with a poor prognosis. Recently, a method to classify SCLC by the expression status of four transcription factors, ASCL1, NEUROD1, POU2F3, and YAP1, was proposed. Here, we investigated the potential relationships between expression of these four transcription factors and the effect of lurbinectedin.

Methods

mRNA and protein expression of ASCL1, NEUROD1, POU2F3, and YAP1 were quantified in eight SCLC cell lines and analyzed for potential correlations with drug sensitivity. In addition, ASCL1, NEUROD1, POU2F3, and YAP1 expression were evaluated in 105 resected cases of high‐grade neuroendocrine carcinoma of the lung, including 59 resected cases of SCLC.

Results

Based on the results of qRT‐PCR and western blot analyses, the eight SCLC cell lines examined were classified into NEUROD1, POU2F3, and YAP1 subtypes, as well as five ASCL1 subtypes. There were no correlations between cell line subtype classification and drug sensitivity to cisplatin, etoposide, or lurbinectedin. Next, we compared relative mRNA expression levels of each transcription factor with drug sensitivity and found that the higher the mRNA expression level of POU2F3, the lower the IC₅₀ of lurbinectedin. Evaluation of resected SCLC tissue revealed that the composition of subtypes defined by the relative dominance of ASCL1, NEUROD1, POU2F3, and YAP1 was as follows: 61% ASCL1, 15% NEUROD1, 14% POU2F3, 5% YAP1, and 5% all‐negative.

Conclusion

In our experiments, high mRNA expression of POU2F3 in SCLC cell lines correlated with the effect of lurbinectedin.