Immunohistochemical studies of pulmonary large cell neuroendocrine carcinoma: a possible association between staining patterns with neuroendocrine markers and tumor response to chemotherapy

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.

The Unmet Diagnostic and Treatment Needs in Large Cell Neuroendocrine Carcinoma of the Lung

Large cell neuroendocrine carcinoma of the lung (LCNEC) is currently classified as a rare lung cancer subtype, but given the high incidence of lung cancer, the overall number of cases is considerable. The pathologic diagnosis of LCNEC is mainly based on the microscopic appearance of the tumor cells, the mitotic rate, the amount of intra-tumoral necrosis, and the presence of positive neuroendocrine markers identified by immunohistochemistry. Recently, a subdivision into two main categories was proposed based on mutation signatures involving the RB1, TP53, KRAS, and STK11/LKB1 genes, into SCLC-like (small cell lung cancer-like) and NSCLC-like (non-small cell lung cancer-like) LCNEC. In terms of treatment, surgery is still the best option for resectable, stage I-IIIA cases. Chemotherapy and radiotherapy have conflicting evidence. Etoposide/platinum remains the standard chemotherapy regimen. However, based on the newly proposed LCNEC subtypes, some retrospective series report better outcomes using a pathology-driven chemotherapy approach. Encouraging outcomes have also been reported for immunotherapy and targeted therapy, but the real impact of these strategies is still being determined in the absence of adequate prospective clinical trials. The current paper scrutinized the epidemiology, reviewed the reliability of pathologic diagnosis, discussed the need for molecular subtyping, and reviewed the heterogeneity of treatment algorithms in LCNEC.

Optimal Combination of Neuroendocrine Markers for the Detection of High-Grade Neuroendocrine Tumors of the Sinonasal Tract and Lung

PURPOSE OF REVIEW

Identification of neuroendocrine (NE) differentiation is critical to the classification of head and neck (HN) and lung tumors. In combination with tumor morphology, immunohistochemical (IHC) documentation of NE differentiation is necessary for the diagnosis of NE tumors. The purpose of this study is to determine the sensitivity and concordance of two novel NE markers (mASH1, INSM1) across a group of high-grade NE tumors of the sinonasal tract and lung, and to compare their expression with the current widespread use of conventional NE markers, synaptophysin (SYN) and chromogranin A (CGA). In addition, expression of PARP1 is examined as a potential novel therapeutic target.

RECENT FINDINGS

Thirty-nine high-grade NE tumors, 23 of the HN and 16 of the lung, were reevaluated by two subspecialized HN and thoracic pathologists, and subsequently stained with mASH1, INSM1, and PARP1. Sensitivity and degree of concordance of all possible combinations of markers were assessed. Sensitivities (standard error) were as follows: mASH1 41% (0.08), INSM1 44% (0.08), SYN 56% (0.08), and CGA 42% (0.09); combination of all four NE markers: 73% (0.08). Sensitivity and standard error for PARP1 was 90% and 0.05, respectively. Highest sensitivity to detect NE differentiation in high-grade NE tumors of the HN and thoracic region was achieved with a combination of four NE markers. Moderate concordance was found with combinations of mASH1 and INSM1 and traditional NE markers, respectively. Consistent overexpression of PARP1 in high-grade tumors with NE differentiation in the HN and lung opens eligibility for PARP1 inhibitor trials.

Insulinoma-Associated Protein 1 (INSM1): Diagnostic, Prognostic, and Therapeutic Use in Small Cell Lung Cancer

Small cell lung carcinoma (SCLC) is an aggressive and difficult to treat cancer. Although immunohistochemistry is not mandatory for a SCLC diagnosis, it might be required, especially in small samples. Insulinoma-associated protein 1 (INSM1) is expressed in endocrine and nervous tissues during embryogenesis, generally absent in adults and re-expressed in SCLC and other neuroendocrine neoplasms. Its high specificity propelled its use as diagnostic biomarker and an attractive therapeutic target. Herein, we aim to provide a systematic and critical review on the use of INSM1 for diagnosis, prognostication and the treatment of SCLC. An extensive bibliographic search was conducted in PubMed® focusing on articles published since 2015. According to the literature, INSM1 is a highly sensitive (75–100%) and specific (82–100%) neuroendocrine immunohistochemical marker for SCLC diagnosis. It can be used in histological and cytological samples. Although advantageous, its standalone use is currently not recommended. Studies correlating INSM1 expression and prognosis have disclosed contrasting results, although the expression seemed to entail a worse survival. Targeting INSM1 effectively suppressed SCLC growth either as a suicide gene therapy regulator or as an indirect target of molecular-targeted therapy. INSM1 represents a valuable biomarker for a SCLC diagnosis that additionally offers vast opportunities for the development of new prognostic and therapeutic strategies.

Large Cell Neuroendocrine Carcinoma of the Lung: Current Understanding and Challenges

Large cell neuroendocrine carcinoma of the lung (LCNEC) is a rare and highly aggressive type of lung cancer, with a complex biology that shares similarities with both small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). The prognosis of LCNEC is poor, with a median overall survival of 8-12 months. The diagnosis of LCNEC requires the identification of neuroendocrine morphology and the expression of at least one of the neuroendocrine markers (chromogranin A, synaptophysin or CD56). In the last few years, the introduction of next-generation sequencing allowed the identification of molecular subtypes of LCNEC, with prognostic and potential therapeutic implications: one subtype is similar to SCLC (SCLC-like), while the other is similar to NSCLC (NSCLC-like). Because of LCNEC rarity, most evidence comes from small retrospective studies and treatment strategies that are extrapolated from those adopted in patients with SCLC and NSCLC. Nevertheless, limited but promising data about targeted therapies and immune checkpoint inhibitors in patients with LCNEC are emerging. LCNEC clinical management is still controversial and standardized treatment strategies are currently lacking. The aim of this manuscript is to review clinical and molecular data about LCNEC to better understand the optimal management and the potential prognostic and therapeutic implications of molecular subtypes.

Adjuvant chemotherapy, extent of resection, and immunoistochemical neuroendocrine markers as prognostic factors of early-stage large-cell neuroendocrine carcinoma

Background

We investigated whether adjuvant chemotherapy, extent of resection, and immunoistochemical neuroendocrine markers affected survival of patients with the early stage of large‐cell neuroendocrine cancer.

Methods

This was a retrospective multicenter study including consecutive patients undergoing resection of node negative large‐cell neuroendocrine carcinoma. Five‐year survival and disease‐free survival rate were evaluated by the Kaplan–Meier method and the log‐rank test in relation to adjuvant chemotherapy, extent of resection, and immunoistochemical neuroendocrine markers (synaptophysin, chromogranin A, and neuron‐specific enolase).

Results

Our study population included 117 patients; 47 (40%) of these received adjuvant chemotherapy. Patients treated with adjuvant chemotherapy had better survival (74% vs. 45%, p = 0.002) and disease‐free survival (79% vs. 40%, p = 0.001) in all cases except patients with tumor <20 mm (79.5% vs. 57.4%, p = 0.43). Lobectomy compared to sublobar resection was associated with better survival (67% vs. 0.1%, p < 0.0001) and disease‐free survival (65% vs. 0.1%, p < 0.0001) also in patients with tumor <20 mm (79% vs. 28%, p = 0.001). Patients with triple‐positive neuroendocrine markers had better survival (79% vs. 35%, p = 0.0001) and disease‐free survival (69% vs. 42%, p = 0.0008). Regression analysis showed that tumor size <20 mm, lobectomy, adjuvant chemotherapy, and triple‐positive immunistochemical neuroendocrine markers were significant favorable prognostic factors for survival outcomes.

Conclusions

Lobectomy seems to be the management of choice in patients with large‐cell neuroendocrine cancer <20 mm while adjuvant chemotherapy should be administered only in patients with tumor >20 mm.

Clinical-Pathologic Challenges in the Classification of Pulmonary Neuroendocrine Neoplasms and Targets on the Horizon for Future Clinical Practice

Diagnosing a pulmonary neuroendocrine neoplasm (NEN) may be difficult, challenging clinical decision making. In this review, the following key clinical and pathologic issues and informative molecular markers are being discussed: (1) What is the preferred outcome parameter for curatively resected low-grade NENs (carcinoid), for example, overall survival or recurrence-free interval? (2) Does the WHO classification combined with a Ki-67 proliferation index and molecular markers, such as OTP and CD44, offer improved prognostication in low-grade NENs? (3) What is the value of a typical versus atypical carcinoid diagnosis on a biopsy specimen in local and metastatic disease? Diagnosis is difficult in biopsy specimens and recent observations of an increased mitotic rate in metastatic carcinoid from typical to atypical and high-grade NEN can further complicate diagnosis. (4) What is the (ir)relevance of morphologically separating large cell neuroendocrine carcinoma (LCNEC) SCLC and the value of molecular markers (RB1 gene and pRb protein or transcription factors NEUROD1, ASCL1, POU2F3, or YAP1 [NAPY]) to predict systemic treatment outcome? (5) Are additional diagnostic criteria required to accurately separate LCNEC from NSCLC in biopsy specimens? Neuroendocrine morphology can be absent owing to limited sample size leading to missed LCNEC diagnoses. Evaluation of genomic studies on LCNEC and marker studies have identified that a combination of napsin A and neuroendocrine markers could be helpful. Hence, to improve clinical practice, we should consider to adjust our NEN classification incorporating prognostic and predictive markers applicable on biopsy specimens to inform a treatment outcome-driven classification.

Insulinoma-associated Protein 1 (INSM1) in Thoracic Tumors is Less Sensitive but More Specific Compared With Synaptophysin, Chromogranin A, and CD56

OBJECTIVE

Recognition of neuroendocrine differentiation is important for tumor classification and treatment stratification. To detect and confirm neuroendocrine differentiation, a combination of morphology and immunohistochemistry is often required. In this regard, synaptophysin, chromogranin A, and CD56 are established immunohistochemical markers. Insulinoma-associated protein 1 (INSM1) has been suggested as a novel stand-alone marker with the potential to replace the current standard panel. In this study, we compared the sensitivity and specificity of INSM1 and established markers.

MATERIALS AND METHODS

A cohort of 493 lung tumors including 112 typical, 39 atypical carcinoids, 77 large cell neuroendocrine carcinomas, 144 small cell lung cancers, 30 thoracic paragangliomas, 47 adenocarcinomas, and 44 squamous cell carcinomas were selected and tissue microarrays were constructed. Synaptophysin, chromogranin A, CD56, and INSM1 were stained on all cases and evaluated manually as well as with an analysis software. Positivity was defined as ≥1% stained tumor cells in at least 1 of 2 cores per patient.

RESULTS

INSM1 was positive in 305 of 402 tumors with expected neuroendocrine differentiation (typical and atypical carcinoids, large cell neuroendocrine carcinomas, small cell lung cancers, and paraganglioma; sensitivity: 76%). INSM1 was negative in all but 1 of 91 analyzed non-neuroendocrine tumors (adenocarcinomas, squamous cell carcinomas; specificity: 99%). All conventional markers, as well as their combination, had a higher sensitivity (97%) and a lower specificity (78%) for neuroendocrine differentiation compared with INSM1.

CONCLUSIONS

Although INSM1 might be a meaningful adjunct in the differential diagnosis of neuroendocrine neoplasias, a general uncritical vote for replacing the traditional markers by INSM1 may not be justified.

The panel of syntaxin 1 and insulinoma-associated protein 1 outperforms classic neuroendocrine markers in pulmonary neuroendocrine neoplasms

Syntaxin-1 (STX1) is a recently described highly sensitive and specific neuroendocrine marker. We evaluated the applicability of STX1 as an immunohistochemical marker in pulmonary neuroendocrine neoplasms (NENs). We compared STX1 with established neuroendocrine markers, including insulinoma-associated protein 1 (INSM1). Typical carcinoids (n = 33), atypical carcinoids (n = 7), small cell lung carcinomas ([SCLCs] n = 30), and large cell neuroendocrine lung carcinomas (n = 17) were immunostained using tissue microarray for STX1, chromogranin A, synaptophysin, CD56, and INSM1. Eighty-four of eighty-seven (96.5%) NENs showed STX1 positivity. Carcinoids and LCNECs typically presented a combined strong membranous and weak cytoplasmic staining pattern; cytoplasmic expression was predominately observed in SCLCs. The sensitivity of STX1 was 90% in SCLCs and 100% in typical carcinoids, atypical carcinoids, and large cell neuroendocrine lung carcinomas. The overall sensitivity of STX1 in pulmonary NENs was 96.6%, and the sensitivity of the other markers was as follows: chromogranin A (85.2%), synaptophysin (85.2%), CD56 (92.9%), and INSM1 (97.7%). STX1 was found to be an excellent neuroendocrine marker of pulmonary NENs, with sensitivity and specificity surpassing that of classic markers. We propose a panel of STX1 and INSM1 for the routine immunohistochemical workup of pulmonary NENs.

Outcomes for Surgery in Stage IA Large Cell Lung Neuroendocrine Compared With Other Types of Non-Small Cell Lung Cancer: A Propensity Score Matching Study Based on the Surveillance, Epidemiology, and End Results (SEER) Database

Background

Pulmonary large cell neuroendocrine cancer (LCNEC) is commonly classified as non-small cell lung cancer (NSCLC). Even for stage I disease, after surgery the survival is always poor, but clinical research on LCNEC is scant and always with unsatisfying sample sizes. Thus, we conduct the first study using the Surveillance, Epidemiology, and End Results (SEER) database to compare survival after surgery between stage I LCNEC and other types of NSCLC.

Methods

From 2004 to 2016, 473 patients with stage IA LCNEC, 17,669 patients with lung adenocarcinoma (LADC) and 8,475 patients with lung squamous cell cancer (LSCC), all treated with surgery were identified. In addition, 1:1 PSM was used, and overall (OS) and cancer-specific survival (CSS) between groups were compared.

Results

The 5-year OS rates and CSS rates for LCNEC were 52.5% and 81.5%, respectively. Overall, both OS and CSS were significantly superior for stage IA LADC than LCNEC (for OS: HR 0.636, 95% CI 0.568-0.712; for CSS: HR 0.688, 95% CI 0.561–0.842, LCNEC as reference), while comparable for LSCC with LCNEC (for OS: HR 0.974, 95% CI 0.869–1.091; for CSS: HR 0.907, 95% CI 0.738–1.115). PSM generated 471 pairs when LCNEC was compared with LADC and both OS and CSS were significantly better in LADC than LCNEC (for OS: HR 0.580, 95% CI 0.491–0.686; for CSS: HR 0.602, 95% CI 0.446–0.814). Of note, for the subgroup of patients ≤ 65 years old, HRs for both OS and CSS were lower (for OS: HR 0.470; for CSS: HR 0.482). As for comparison between LCNEC and LSCC, PSM generated 470 pairs. Differently, only CSS was significantly superior in LSCC than LCNEC (HR 0.563, 95% CI 0.392–0.807), while OS was not. Further grouping by age showed only CSS between two groups for patients with age ≤ 65 years old was significantly different (P = 0.006).

Conclusions

We report the first survival comparison after surgery between stage IA LCNEC and other types of NSCLC by SEER database and PSM. Our results demonstrated after surgery, stage IA LCNEC was worse in survival, especially compared to LADC. Extra clinical care should be paid, especially for younger patients. More studies investigating adjuvant therapy are warranted.

Diagnostic Value of Insulinoma-Associated Protein 1 (INSM1) and Comparison With Established Neuroendocrine Markers in Pulmonary Cancers

CONTEXT.—

The diagnostic distinction of pulmonary neuroendocrine (NE) tumors from non-small cell lung carcinomas (NSCLCs) is clinically relevant for prognostication and treatment. Diagnosis is based on morphology and immunohistochemical staining.

OBJECTIVE.—

To determine the diagnostic value of insulinoma-associated protein 1 (INSM1), in comparison with established NE markers, in pulmonary tumors.

DESIGN.—

Fifty-four pulmonary NE tumors and 632 NSCLCs were stained for INSM1, CD56, chromogranin A, and synaptophysin. In a subset, gene expression data were available for analysis. Also, 419 metastases to the lungs were stained for INSM1. A literature search identified 39 additional studies with data on NE markers in lung cancers from the last 15 years. Seven of these included data on INSM1.

RESULTS.—

A positive INSM1 staining was seen in 39 of 54 NE tumors (72%) and 6 of 623 NSCLCs (1%). The corresponding numbers were 47 of 54 (87%) and 14 of 626 (2%) for CD56, 30 of 54 (56%) and 6 of 629 (1%) for chromogranin A, and 46 of 54 (85%) and 49 of 630 (8%) for synaptophysin, respectively. Analysis of literature data revealed that CD56 and INSM1 were the best markers for identification of high-grade NE pulmonary tumors when considering both sensitivity and specificity, while synaptophysin also showed good sensitivity. INSM1 gene expression was clearly associated with NE histology.

CONCLUSIONS.—

The solid data of both our and previous studies confirm the diagnostic value of INSM1 as a NE marker in pulmonary pathology. The combination of CD56 with INSM1 and/or synaptophysin should be the first-hand choice to confirm pulmonary high-grade NE tumors. INSM1 gene expression could be used to predict NE tumor histology.

DLL3 expression is a predictive marker of sensitivity to adjuvant chemotherapy for pulmonary LCNEC

Background

The mammalian Notch family ligands delta‐like 3 (DLL3) is reported to be a potential therapeutic target for large cell neuroendocrine carcinomas (LCNEC). The effect of DLL3 expression on LCNEC prognosis has not yet been elucidated.

Methods

We reviewed the medical records of 70 LCNEC patients undergoing surgical resection between 2001 and 2015 using a prospectively maintained database. We performed immunohistochemistry for DLL3 and investigated the correlation between the sensitivity of LCNEC to platinum‐based adjuvant chemotherapy.

Results

DLL3 expression was positive in 26 (37.1%) LCNEC patients. A total of 23 patients (32.9%) received platinum‐based adjuvant chemotherapy. Among patients with DLL3 expression‐positive tumors, no difference was found in the five‐year overall survival (OS) or recurrence‐free survival (RFS) between patients with and without adjuvant chemotherapy (surgery + chemotherapy vs. surgery alone, five‐year OS: 58.3% vs. 35.7% P = 0.36, five‐year RFS: 41.7% vs. 35.7% P = 0.74). In contrast, among patients with DLL3‐negative tumors, significantly greater five‐year OS and RFS rates were observed for patients with adjuvant chemotherapy than for those without it (surgery + chemotherapy vs. surgery alone: five‐year OS: 90.0% vs. 26.9% P<0.01, five‐year RFS: 80.0% vs. 21.7% P < 0.01). A multivariate analysis for the RFS revealed that adjuvant chemotherapy was a significant independent prognostic factor among patients with DLL3‐negative tumors (hazard ratio [HR]: 0.05, 95% confidence interval [CI]: 0.01–0.41, P < 0.01), although it was not a factor among patients with DLL3‐positive tumors (HR: 0.73, 95% CI: 0.23–2.27, P = 0.58).

Conclusions

Our results revealed that DLL3 is a predictive marker of sensitivity to platinum‐based adjuvant chemotherapy for LCNEC.

Key points

Significant findings of the study

DLL3 was a predictive marker of sensitivity to platinum‐based adjuvant chemotherapy for LCNEC. Among patients with DLL3 expression‐negative LCNEC, platinum‐based adjuvant chemotherapy significantly improved the OS and RFS, although it did not do so among patients with DLL3 expression‐positive LCNEC.

What this study adds

Our results suggest that DLL3 expression‐positive LCNEC may be better treated with other types of adjuvant chemotherapy, such as the anti‐DLL3 therapies if these effects are confirmed by ongoing clinical research.

Insulinoma-associated protein 1 is a prognostic biomarker in pulmonary high-grade neuroendocrine carcinoma

BACKGROUNDS AND OBJECTIVES

Recent studies have suggested that insulinoma-associated protein 1 (INSM1) is a useful marker for pathological diagnosis of pulmonary neuroendocrine tumors. In the present study, we investigated the association between INSM1 expression and prognosis in patients with pulmonary high-grade neuroendocrine carcinomas (HGNEC) and assessed the usefulness of INSM1 as a prognostic biomarker in these patients.

METHODS

Seventy-five consecutive patients with HGNEC who underwent complete surgical resections from January 2000 to December 2018 were enrolled in this study. We classified these patients into two groups: the INSM1-positive group (n = 59) and INSM1-negative group (n = 16). We compared the clinicopathological characteristics, overall survival (OS), and recurrence-free survival (RFS) between the groups. In addition, we performed univariate and multivariate analyses to identify the prognostic factors associated with postoperative survival.

RESULTS

Significant differences in tumor diameter and vascular invasion between the groups were found. OS and RFS were significantly poorer in the INSM1-positive group than in the INSM1-negative group. Univariate and multivariate analyses revealed that INSM1 expression was the strongest predictor of poor prognosis for OS and RFS.

CONCLUSIONS

INSM1 expression had the greatest influence on the prognosis in patients with HGNEC and may be a prognostic biomarker in these patients.

Neuroendocrine tumors of the lung: clinicopathological and molecular features

In 1970, neuroendocrine tumors of the lung were classified into three categories: typical carcinoid (TC), atypical carcinoid (AC), and small cell lung carcinoma (SCLC). The third edition of the World Health Organization (WHO) classification in 1999 defined large cell neuroendocrine carcinoma (LCNEC) as a variant of large cell carcinomas, whereas the fourth edition of the WHO classification redefined LCNEC as a neuroendocrine tumor. Currently, neuroendocrine tumors of the lung are classified into four main categories: TC, AC, LCNEC, and SCLC. Although the treatments for TC, AC, and SCLC have not changed remarkably, the treatment strategy for LCNEC is not yet established because of its reclassification from a variant of "large cell carcinoma" to a new category of "neuroendocrine tumor". In this review article, we discuss the pathological findings, biological behavior, and treatment of neuroendocrine tumors of the lung.

Prognostic markers in resected large cell neuroendocrine carcinoma: a multicentre retrospective analysis

Background

Large cell neuroendocrine carcinomas (LCNEC) are rare pulmonary malignancies. Reported survival rates are heterogeneous and the optimal therapeutic strategy is still debated. The prognosis of LCNEC is generally inferior compared to other non-small lung cancers. In early stages, surgery is recommended but might not be sufficient alone.

Methods

We retrospectively analyzed all consecutive LCNEC patients operated at three institutions with curative intent between May 2005 and January 2017. Data retrieved from individual clinical databases were analyzed with the aim to identify prognostic parameters.

Results

A total of 251 patients with LCNEC underwent curative intent surgery during the observation period. The median age was 64 years, 156 patients (62.2%) were male and 88.4% were smokers. The pathologic AJCC stage was I in 136 patients, II in 77, III in 33, and IV in 5 patients. Median follow-up was 26 months. Lymphatic vessel invasion (P=0.031) was identified as significant prognostic factor by multivariable analysis. There was a trend towards decreased survival in patients with blood vessel invasion (P=0.067). Even in earlier tumor stages, adjuvant chemotherapy had a positive effect on survival. The overall 1-, 3- and 5-year survival rates were 79.2%, 48.6% and 38.8% respectively.

Conclusions

Lymphatic invasion (L1) is an independent prognostic factor. Surgery in LCNEC is beneficial in early tumor stages and platinum-based adjuvant chemotherapy may help in achieving better long-term outcomes resulting in most obvious survival differences in stage Ib.

Neuroendocrine marker staining pattern categorization of small-sized pulmonary large cell neuroendocrine carcinoma

Background

The aim of this study was to identify subgroups with good or bad prognosis in patients with pulmonary large cell neuroendocrine carcinoma (LCNEC) based on immunostaining patterns with neuroendocrine markers and compare them with small cell lung carcinoma (SCLC).

Methods

From January 2001 to December 2017, of all patients with resected LCNEC and SCLC, we selected patients whose pathological tumor sizes were ≤30 mm in diameter (defined as small‐sized tumors) and who underwent complete resection with lymphadenectomy. We classified patients with small‐sized LCNEC (sLCNEC) into two subgroups based on immunostaining patterns with three neuroendocrine markers (chromogranin A, synaptophysin, and NCAM) and compared them to small‐sized SCLC (sSCLC).

Results

A total of 48 patients with sLCNEC and 39 patients with sSCLC were enrolled. Of 48 patients with sLCNEC, 21 were categorized as the small‐sized triple‐positive group (sTP), whose patients were positive for the three neuroendocrine markers, and 27 patients were categorized as the small‐sized nontriple‐positive group (sNTP), whose patients were not positive for all three neuroendocrine markers. The percentage of lymph node metastasis was significantly lower in sNTP than in sTP and sSCLC. There was no significant difference in overall survival, but recurrence‐free survival (RFS) and tumor‐specific survival (TSS) were significantly poorer in sTP and sSCLC than in sNTP. Multivariate analysis revealed sTP and sSCLC were independent prognostic factors for poorer RFS and TSS than those of sNTP.

Conclusions

The sNTP subgroup had a good prognosis and the sTP subgroup a poor prognosis. There were some similarities in clinicopathological features between sTP and sSCLC.

Lung Large Cell Neuroendocrine Carcinoma: An Analysis of Patients from the Surveillance, Epidemiology, and End-Results (SEER) Database

Background

The aim of this study was to assess the incidence, clinicopathologic characteristics, prognostic factors, and treatment outcomes in lung large cell neuroendocrine carcinoma (LCNEC).

Material/Methods

Patients diagnosed with lung LCNEC between 2000 and 2013 were identified using the Surveillance, Epidemiology, and End-Results database. Kaplan–Meier methods and univariate and multivariate analyses were used for statistical analysis.

Results

A total of 2097 patients were identified. The total age-adjusted incidence rate of lung LCNEC was 0.3/100 000, with a rise in incidence over the study period. The 5-year lung cancer-specific survival (LCSS) and overall survival (OS) were 20.7% and 16.7%, respectively. Multivariate analysis indicated that age ≥65 years, male sex, advanced tumor stage, advanced nodal stage, not undergoing surgery. and not undergoing chemotherapy were independent adverse indicators for survival outcomes. After stratification by tumor stage, undergoing surgery was associated with more favorable LCSS and OS compared with those without surgery, regardless of tumor stage.

Conclusions

LCNEC is a rare lung cancer subtype with a dismal prognosis. Primary surgical treatment has significant survival benefits, even for stage IV patients. The optimal treatment strategies for lung LCNEC require further investigation.

Efficacy of perioperative chemotherapy for pulmonary high-grade neuroendocrine carcinomas: a propensity score matching analysis

Background

Large-cell neuroendocrine carcinoma (LCNEC) and small cell lung cancer (SCLC) are categorized as high-grade neuroendocrine carcinoma (HGNEC). We analyzed the efficacy of perioperative chemotherapy for HGNEC and the prognostic factors.

Methods

We retrospectively reviewed the medical records of patients who underwent tumor resection and were diagnosed with HGNEC between January 2001 and December 2014. The overall survival (OS) was estimated by the Kaplan-Meier method. Propensity score matching was performed to compare the OS between the treatment groups. Multivariate analyses using a Cox proportional hazards model were performed to search for prognostic factors for HGNEC.

Results

We analyzed 146 HGNEC patients (LCNEC n=92, SCLC n=54) without synchronous multiple cancers, who underwent complete resection. Seventy patients (LCNEC n=31, SCLC n=32) received perioperative chemotherapy and all of them received a platinum-based anticancer drug. Perioperative chemotherapy significantly improved the 5-year OS rates of HGNEC patients (all stages: 74.5% vs. 34.7%, P<0.01, stage I: 88.5% vs. 40.0%, P<0.01). The efficacy of perioperative chemotherapy was similar between LCNEC and SCLC patients [LCNEC all stages: hazard ratio (HR) 0.27, P<0.01, LCNEC stage I: HR 0.27, P=0.01; SCLC all stages: HR 0.38, P=0.02, SCLC stage I: HR 0.34, P=0.06]. The survival benefit of perioperative chemotherapy for HGNEC patients was confirmed by propensity score matching analysis (HR 0.31, P<0.01). The multivariate analysis revealed that perioperative chemotherapy (HR 0.29, P<0.01), sublobar resection (HR 2.11, P=0.04), and lymph node metastasis (HR 3.34, P<0.01) were independently associated with survival.

Conclusions

Surgical resection combined with perioperative chemotherapy was considered to be effective even for stage I HGNEC patients. Sublobar resection might increase the risk of death in HGNEC patients.

INSM1 Demonstrates Superior Performance to the Individual and Combined Use of Synaptophysin, Chromogranin and CD56 for Diagnosing Neuroendocrine Tumors of the Thoracic Cavity

Despite the importance of recognizing neuroendocrine differentiation when diagnosing tumors of the thoracic cavity, the sensitivity of traditional neuroendocrine markers is suboptimal, particularly for high-grade neuroendocrine carcinomas such as small cell lung carcinoma and large cell neuroendocrine carcinoma. To increase sensitivity, neuroendocrine markers are routinely ordered as panels of multiple immunostains where any single positive marker is regarded as sufficient evidence of neuroendocrine differentiation. Insulinoma-associated protein 1 (INSM1) is a well-validated transcription factor of neuroendocrine differentiation that has only recently been evaluated for diagnostic use. We performed INSM1 immunohistochemistry on a large series of thoracic neuroendocrine and non-neuroendocrine tumors and compared its performance to synaptophysin, chromogranin, and CD56. INSM1 was positive in 94.9% of small cell lung carcinomas and 91.3% of large cell neuroendocrine carcinomas, compared with 74.4% and 78.3% with the combined panel of traditional markers. INSM1 also stained all (100%) of the atypical carcinoids, typical carcinoids and mediastinal paragangliomas, but only 3.3% of adenocarcinomas and 4.2% of squamous cell carcinomas. Overall, INSM1 demonstrated a sensitivity of 96.4% across all grades of thoracic neuroendocrine tumors, significantly more than the 87.4% using the panel of traditional markers (P=0.02). INSM1 is sufficiently sensitive and specific to serve as a standalone first-line marker of neuroendocrine differentiation. A more restrained approach to immunohistochemical analysis of small thoracic biopsies is appropriate given the expanding demand on this limited material for therapeutic biomarker analysis.

Large Cell Neuroendocrine Carcinoma of the Lung: Clinico-Pathologic Features, Treatment, and Outcomes

BACKGROUND

Large cell neuroendocrine carcinoma (LCNEC) accounts for approximately 3% of lung cancers. Pathologic classification and optimal therapies are debated. We report the clinicopathologic features, treatment and survival of a series of patients with stage IV LCNEC.

MATERIALS AND METHODS

Cases of pathologically-confirmed stage IV LCNEC evaluated at Memorial Sloan Kettering Cancer Center from 2006 to 2013 were identified. We collected demographic, treatment, and survival data. Available radiology was evaluated by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 criteria.

RESULTS

Forty-nine patients with stage IV LCNEC were identified. The median age was 64 years, 63% of patients were male, and 88% were smokers. Twenty-three patients (n = 23/49; 47%) had brain metastases, 17 at diagnosis and 6 during the disease course. Seventeen LCNEC patients (35%) had molecular testing, of which 24% had KRAS mutations (n = 4/17). Treatment data for first-line metastatic disease was available on 37 patients: 70% (n = 26) received platinum/etoposide and 30% (n = 11) received other regimens. RECIST was completed on 23 patients with available imaging; objective response rate was 37% (95% confidence interval, 16%-62%) with platinum/etoposide, while those treated with other first-line regimens did not achieve a response. Median overall survival was 10.2 months (95% confidence interval, 8.6-16.4 months) for the entire cohort.

CONCLUSION

Patients with stage IV LCNEC have a high incidence of brain metastases. KRAS mutations are common. Patients with stage IV LCNEC do not respond as well to platinum/etoposide compared with historic data for extensive stage small-cell lung cancer; however, the prognosis is similar. Prospective studies are needed to define optimum therapy for stage IV LCNEC.

Breast metastasis and lung large-cell neuroendocrine carcinoma: first clinical observation

BACKGROUND AND AIMS

The lung large-cell neuroendocrine carcinoma (LCNEC) is a very rare aggressive neuroendocrine tumor with a high propensity to metastasize and very poor prognosis. We report an atypical presentation of lung LCNEC was diagnosed from a metastatic nodule on the breast.

METHODS

Our patient is a 59-years-old woman that presented in March 2014 nonproductive cough. A CT scan showed multiple brain, lung, adrenal gland and liver secondary lesions; moreover, it revealed a breast right nodule near the chest measuring 1.8 cm. The breast nodule and lung lesions were biopsied and their histology and molecular diagnosis were LCNEC of the lung. To our knowledge, this is the first documented case of breast metastasis from LCNEC of the lung.

RESULTS

Furthermore, breast metastasis from extramammary malignancy is uncommon and its diagnosis is difficult but important for proper management and prediction of prognosis. Therefore, a careful clinical history with a thorough clinical examination is needed to make the correct diagnosis. Moreover, metastasis to the breast should be considered in any patient with a known primary malignant tumor history who presents with a breast lump. Anyhow, pathological examination should be performed to differentiate the primary breast cancer from metastatic tumor.

CONCLUSION

Therefore, an accurate diagnosis of breast metastases may not only avoid unnecessary breast resection, more importantly it is crucial to determine an appropriate and systemic treatment.

A retrospective analysis of the clinicopathological characteristics of large cell carcinoma of the lung

The aim of the present study was to analyze and summarize the clinicopathological characteristics of large-cell lung carcinoma (LCLC) of the lung, in order to improve the definite diagnosis rate of LCLC. Clinicopathological data of 174 patients with LCLC, confirmed pathologically, were retrospectively reviewed. The 174 cases of LCLC accounted for 5.7% of the total lung cancer cases during the corresponding time period at the Affiliated Cancer Hospital of Tianjin Medical University (Tianjin, China), among which there were 131 males and 43 females with an average age of 61.4 years. The postoperative pathological diagnosis of the 174 cases showed 80 cases of classic LCLC, 64 cases of large cell neuroendocrine carcinoma (LCNEC), six cases of combined LCNEC, 19 cases of basaloid carcinoma, three cases of clear cell carcinoma and two cases of lymphoepithelioma-like carcinoma. Of the total 174 LCLC cases, 96 patients exhibited lymph node metastasis. LCLC is a highly aggressive malignancy with a high tendency of invasion and metastasis, although the incidence rate is low. A definite diagnosis of LCLC primarily relies on the pathological diagnosis. Each subtype of LCLC has its own pathomorphological and immunohistochemical characteristics.

Treatment options for patients with large cell neuroendocrine carcinoma of the lung

Large cell neuroendocrine carcinoma (LCNEC) of the lung is categorized as a variant of large cell carcinomas, and LCNEC tumors display biological behaviors resembling those of small cell lung carcinomas and features of high-grade neuroendocrine tumors. Because patients with LCNEC have a poor prognosis, surgery alone is not sufficient. Multimodality therapies, including adjuvant chemotherapy, appear promising for improved prognosis in patients with LCNEC. In this review article, we discuss treatment options for patients with LCNEC of the lung.