Large cell neuroendocrine carcinoma of the lung: a comparison with large cell carcinoma with neuroendocrine morphology and small cell carcinoma

Comparative study of Rb1, cyclin D1 and p16 immunohistochemistry expression to distinguish lung small cell carcinoma and large cell neuroendocrine carcinoma

INTRODUCTION

Large cell neuroendocrine carcinoma (LCNEC) and small cell carcinoma (SCLC) of lung encompass high grade neuroendocrine tumour category and share several fundamental features. As both tumours may respond to different treatment modalities and show unique molecular alterations, distinction between the two is clinically relevant but can be challenging due to sampling and fixation issues, and shared morphologic features.

METHODS

Surgically resected primary SCLC (N=129) and LCNEC (N=27) were immunohistochemically stained with Rb1, cyclin D1 and p16, using tissue microarray (TMA), and expression patterns of the proteins were compared between the two to identify the discriminatory pattern.

RESULTS

All markers had high diagnostic accuracy; Rb1 was the highest followed by p16 and cyclin D1. Majority of SCLC had the pattern Rb1-/p16+/cyclin D1- and more than half of LCNEC had Rb1+/p16-/cyclin D1+. Overall, the expression pattern Rb1- and cyclin D1- was strongly associated with the diagnosis of SCLC, while the pattern Rb1+ and/or cyclin D1+ was strongly associated with LCNEC. The use of this simplified expression pattern leads to a diagnostic accuracy of 97.3%. p16 did not add to further discrimination. The heterogeneity in Rb1, cyclin D1 and p16 expression was insignificant in SCLCs compared with LCNECs.

CONCLUSIONS

Use of Rb1, cyclin D1 and p16 immunohistochemistry can distinguish the two with high accuracy. Notably, Rb1-/cyclin D1- pattern in given tumour sample would confirm the diagnosis of SCLC. Our results could be extrapolated and applied to routine diagnostic samples such as biopsies and cytology samples.

Clinic and genetic similarity assessments of atypical carcinoid, neuroendocrine neoplasm with atypical carcinoid morphology and elevated mitotic count and large cell neuroendocrine carcinoma

Background

Pulmonary neuroendocrine neoplasms can be divided into typical carcinoid, atypical carcinoid, large cell neuroendocrine carcinoma, and small cell (lung) carcinoma. According to the World Health Organization, these four neoplasms have different characteristics and morphological traits, mitotic counts, and necrotic status. Importantly, “a grey-zone” neoplasm with an atypical carcinoid-like morphology, where the mitotic rate exceeds the criterion of 10 mitoses per 2 mm², have still not been well classified. In clinical practice, the most controversial area is the limit of 11 mitoses to distinguish between atypical carcinoids and large cell neuroendocrine carcinomas.

Methods

Basic and clinical information was obtained from patient medical records. A series of grey-zone patients (n = 8) were selected for exploring their clinicopathological features. In addition, patients with atypical carcinoids (n = 9) and classical large cell neuroendocrine carcinomas (n = 14) were also included to compare their similarity to these neoplasms with respect to tumour morphology and immunohistochemical staining.

Results

We found that these grey-zone tumour sizes varied and affected mainly middle-aged and older men who smoked. Furthermore, similar gene mutations were found in the grey-zone neoplasms and large cell neuroendocrine carcinomas, for the mutated genes of these two are mainly involved in PI3K-Akt signal pathways and Pathways in cancer, including a biallelic alteration of TP53/RB1 and KEAP1.

Conclusions

Our findings indicate that neuroendocrine neoplasm with atypical carcinoid morphology and elevated mitotic counts is more similar to large cell neuroendocrine carcinoma than atypical carcinoid. Furthermore, this study may help improve diagnosing these special cases in clinical practice to avoid misdiagnosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09391-w.

Pulmonary large cell carcinoma with neuroendocrine morphology shows genetic similarity to large cell neuroendocrine carcinoma

Background

Large cell neuroendocrine carcinoma (LCNEC) is a high-grade malignant pulmonary neuroendocrine tumour. The distinction of pulmonary large cell carcinoma (LCC) and LCNEC is based on the presence of neuroendocrine morphology and the expression of at least one neuroendocrine marker in at least 10% of tumour cells in the latter. According to the current classification, LCC with neuroendocrine morphology and without neuroendocrine marker expression is classified as LCC. This subgroup we have named LCNEC-null and aimed to analyze its characteristics.

Methods

31 surgical samples resected in West China Hospital of Sichuan University between 2017 to 2021 were collected, including 7 traditional LCCs, 11 LCNEC-nulls and 13 LCNECs. Each case was conducted to immunohistochemistry and 425-panel-NGS.

Results

Compared to other LCCs, detailed analysis of LCNEC-nulls revealed biological features similar to those of LCNECs, especially for immunohistochemistry and molecular analysis: 1. diffusive, coarse granular and high expression of Pan-CK; 2. rare PD-L1 expression; 3. High rate of p53 expression and Rb deficiency 4. abundant genetic alterations are similar to LCNEC. All characteristics above deviated from traditional LCC, indicating they have the same origin as LCNEC. Furthermore, LCNEC could be genetically divided into two subtypes when we reclassified LCNEC-null as LCNEC, and the mutational type and prognosis differed significantly.

Conclusions

We consider that LCNEC-null should be reclassified as LCNEC based on analysis above. In addition, two genetic types of LCNEC with different prognosis also indicate two mechanism of tumour formation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-022-01204-9.

Perioperative chemotherapy with pemetrexed and cisplatin for pulmonary large-cell neuroendocrine carcinoma: a case report and literature review

Background

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is associated with poor prognosis, and its treatment strategy is still controversial, especially regarding chemotherapy regimens.

Case report

We present the case of a 49-year-old Chinese male with primary pulmonary LCNEC treated with neoadjuvant and adjuvant chemotherapy with cisplatin plus pemetrexed. A suspected quasi-circular mass in the left lower pulmonary lobe and an enlarged mediastinal lymph node were found. The patient was diagnosed with adenocarcinoma with neuroendocrine differentiation based on computerized tomography-guided percutaneous lung biopsy. An EGFR gene mutation test showed negative results. Cisplatin and pemetrexed were administered as the neoadjuvant chemotherapy regimen. The primary lesion had reduced markedly, and the enlarged mediastinal lymph node had disappeared after two cycles of neoadjuvant chemotherapy. A left lower lobectomy and mediastinal lymph node dissection were performed. The lesion was confirmed as LCNEC based on postoperative histopathological analysis and immunohistochemical results. The patient underwent four cycles of adjuvant chemotherapy with cisplatin and pemetrexed for a month postoperatively, followed by postoperative adjuvant radiotherapy. The patient was still alive after a follow-up of 24 months, with no evidence of tumor recurrence.

Conclusion

Cisplatin combined with pemetrexed is effective and safe for patients with pulmonary LCNEC.

The Use of Immunohistochemistry Improves the Diagnosis of Small Cell Lung Cancer and Its Differential Diagnosis. An International Reproducibility Study in a Demanding Set of Cases

INTRODUCTION

The current WHO classification of lung cancer states that a diagnosis of SCLC can be reliably made on routine histological and cytological grounds but immunohistochemistry (IHC) may be required, particularly (1) in cases in which histologic features are equivocal and (2) in cases in which the pathologist wants to increase confidence in diagnosis. However, reproducibility studies based on hematoxylin and eosin-stained slides alone for SCLC versus large cell neuroendocrine carcinoma (LCNEC) have shown pairwise κ scores ranging from 0.35 to 0.81. This study examines whether judicious use of IHC improves diagnostic reproducibility for SCLC.

METHODS

Nineteen lung pathologists studied interactive digital images of 79 tumors, predominantly neuroendocrine lung tumors. Images of resection and biopsy specimens were used to make diagnoses solely on the basis of morphologic features (level 1), morphologic features along with requested IHC staining results (level 2), and all available IHC staining results (level 3).

RESULTS

For the 19 pathologists reading all 79 cases, the rate of agreement for level 1 was 64.7%, and it increased to 73.2% and 77.5% in levels 2 and 3, respectively. With IHC, κ scores for four tumor categories (SCLC, LCNEC, carcinoid tumors, and other) increased in resection samples from 0.43 to 0.60 and in biopsy specimens from 0.43 to 0.64.

CONCLUSIONS

Diagnosis using hematoxylin and eosin staining alone showeds moderate agreement among pathologists in tumors with neuroendocrine morphology, but agreement improved to good in most cases with the judicious use of IHC, especially in the diagnosis of SCLC. An approach for IHC in the differential diagnosis of SCLC is provided.

Treatment outcomes of patients with different subtypes of large cell carcinoma of the lung

BACKGROUND

Although large cell neuroendocrine carcinoma (LCNEC) and lymphoepithelioma-like carcinoma (LELC) are the variants of large cell carcinoma (LCC) of lung, there are few studies comparing them. The aim of this study was to compare the clinical characteristic and treatment outcomes of LCNEC, LELC, and classic LCC.

METHODS

Patients with LCNEC, LELC, or classic LCC were identified in a prospectively collected database, and their data were analyzed.

RESULTS

A total of 46 patients with classic LCC, 30 with LCNEC, and 18 with LELC, who received surgical resection with curative intent, were identified and included in the analysis. Patients with LELC were younger, and the frequency of nonsmokers was greater than in patients with classic LCC or LCNEC. In patients with LCNEC or LELC, most lesions were located on the left side. There were 5 surgical deaths, and the median follow-up time of the surviving patients was 44.1 months. The 5-year disease free survival among the three subgroups was similar (p = 0.601), but patients with LELC had a significantly better overall survival than the other two subgroups (LELC vs classic LCC, p = 0.009; LELC vs LCNEC, p = 0.002). Multivariate analysis showed tumor location site, tumor stage, and LELC were independent prognostic factors of overall survival.

CONCLUSIONS

The clinical manifestations and treatment outcomes of LCNEC, LELC, and classic LCC are different. LCNEC has a poor survival, and survival is not different than that of classic LCC. LELC is associated with younger age and a higher frequency of nonsmokers, and the treatment outcomes are better than those of other subtypes.

Large cell carcinoma of lung: On the verge of extinction?

Pulmonary large cell carcinoma is a tumor whose existence as a defined entity has been challenged in recent years in the wake of advances in techniques to subtype lung cancer. Large cell carcinoma has been defined in the past as a tumor that lacks morphologic evidence of either glandular or squamous differentiation. This rather vague definition and the inclusion of more specific entities such as large cell neuroendocrine carcinoma, basaloid carcinoma, lymphoepithelioma-like carcinoma, clear cell carcinoma, and large cell carcinoma with rhabdoid phenotype as subtypes of large cell carcinoma has not only diluted the homogeneity of this entity but has also contributed to its use as a "wastebin" category for tumors lacking a definitive morphologic pattern. Today, there is increasing evidence that a large proportion of these tumors can be subtyped further using modern immunohistochemical and molecular methods. This is of special value not only from a diagnostic point of view but becomes increasingly important in terms of treatment choice since the selection of therapeutic modalities is often based on specific tumor histology. When viewed in this light, large cell carcinoma of the lung--as defined today--appears to be an outdated entity that needs to be reevaluated taking into account not only light microscopic findings but also the results of adjunct techniques such as immunohistochemistry and molecular profiling so that patients can benefit from more targeted therapies. This review examines the entity of pulmonary large cell carcinoma from these aspects and tries to delineate a practical diagnostic approach until further redefinition of this tumor is in place.

Chemotherapy for pulmonary large cell neuroendocrine carcinoma: similar to that for small cell lung cancer or non-small cell lung cancer?

BACKGROUND

There is controversy regarding palliative chemotherapy for large cell neuroendocrine carcinoma (LCNEC). We evaluated whether advanced LCNEC should be treated similarly to small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

The clinical reports and tumor specimens of 45 consecutive patients who were diagnosed with advanced LCNEC were reviewed. They were divided into SCLC (n=11) and NSCLC regimen groups (n=34) according to first-line chemotherapeutic regimens.

RESULTS

Most patients were male (96%) and smokers (93%) with a median age of 64 years. Neuroendocrine differentiation was established in 42 (93%) tumors by immunohistochemical analyses. Regarding the efficacy of first-line chemotherapy in the SCLC and NSCLC regimen groups, the response rates were 73% and 50% (P=0.19), and the median progression-free survival times were 6.1 and 4.9 months (P=0.41), respectively. The difference in overall survival between the two treatment groups was 7.3 months (16.5 vs. 9.2 months, P=0.10). There was also a considerable difference in the type and efficacy of salvage chemotherapeutic regimens between the two groups: salvage regimens with irinotecan, platinum, or taxanes were commonly used with relatively high objective responses in the SCLC regimen group, whereas frequently used agents in the NSCLC regimen group such as pemetrexed, gefitinib, or erlotinib were associated with no objective response.

CONCLUSION

Regarding palliative chemotherapy for advanced LCNEC, treatment similar to SCLC is more appropriate than NSCLC.

Cytokine synthesis by chondroblastoma: relation to local inflammation

PURPOSE

To investigate cytokine production by chondroblastoma in inducing local inflammation and adjacent-joint arthritis.

METHODS

Immunohistochemical analyses of curetted tissues using anti-human interleukin (IL)-1 beta, IL- 6, IL-8, and tumour necrosis factor (TNF)-alpha were performed for 6 patients with chondroblastoma and 3 patients with giant cell tumour (GCT) of bone. In addition, prostaglandin E2, IL-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, and TNF-alpha in the cyst fluid of one of the patients with chondroblastoma and 2 with GCT of bone were measured using immunoassay kits.

RESULTS

More positive staining for IL-1 beta, IL-8, IL- 6, and TNF-alpha was shown in chondroblastoma than GCT of bone samples. Osteoclast-like giant cells in chondroblastomas showed positive staining for IL- 6 only. In addition, concentrations of IL-4, IL-6, and IL-8 in the cyst fluid were higher in the one patient with chondroblastoma than the 2 patients with GCT of bone.

CONCLUSION

Cytokines such as IL-1 beta, IL-8, TNF-alpha, and particularly IL-6 play an important role in local inflammation in patients with chondroblastoma.

Neuroendocrine carcinomas of the lung: a critical analysis

Neuroendocrine carcinomas represent an important group of primary neoplasms in the lung. During the last decades, the nomenclature of these tumors has evolved and the current use of immunohistochemical and molecular biology studies have, to some extent, expanded the conventional view of these tumors. However, the primary diagnosis of most of these lesions is performed on limited biopsy specimens, which may not translate well when one is confronted with a nomenclature that is based on resected material. In addition, for some of these specific entities, some confusion and controversy apparently remain, allowing for the proliferations of different terms that, although they may be dismissed as "semantics," may have a role in interpretation, further subclassification, and, possibly, treatment. Herein we review current concepts regarding the classification of these neoplasms and the role of this classification in our daily practice and discuss how it may impact treatment.

Combined large cell neuroendocrine and endometrioid carcinoma of the endometrium

We present the surgical and pathological findings and follow-up of 5 women diagnosed with combined endometrioid and high-grade neuroendocrine carcinoma of large cell type (LCNEC) arising in the endometrium. The mean age of the women was 75 years (range, 50-88 years). Of the 5 tumors, 4 formed polypoid endometrial masses associated with extensive lymphovascular involvement of the myometrium by neoplastic cells. A single endometrial tumor was formed by LCNEC alone, and 4 tumors were composite with varying proportions formed by endometrioid (4/5) and small cell neuroendocrine carcinoma (1/5). In all 5 LCNEC tumor components, an insular growth pattern was noted, whereas a diffuse (solid) pattern was found in 4 tumors, a trabecular in 2, and rosettes/pseudorosettes in another 2. In all 5 tumors, the LCNEC tumor components were labeled with neuron-specific enolase (NSE). Four tumors were reactive for chromogranin A, CAM 5.2, and p53. Three tumors were labeled for AE1/AE3, CD56 (NCAM), p16, and cytokeratin 7. Synaptophysin was reactive in 2 tumors, and CD117 was found in only a single tumor. Of the 3 endometrioid tumor components examined, all were reactive for NSE. Two tumors were reactive for p16 and p53, 1 for CD56, but none for synaptophysin orchromogranin A. We conclude that LCNEC of the endometrium is a distinct clinicopathological entity with a poor prognosis irrespective of stage. The gross and histomorphological features are often suggestive, but confirmation requires immunoperoxidases, including NSE, synaptophysin, chromogranin A, p16, and p53. Combined endometrioid and high-grade LCNEC possess more characteristics of a type II than a type I endometrial carcinoma.

Pulmonary large cell neuroendocrine carcinoma: its place in the spectrum of pulmonary carcinoma

In 1999, the World Health Organization categorized large cell neuroendocrine carcinoma (LCNEC) as a variant of large cell carcinoma. The World Health Organization categorization not only classified histologic types of large cell carcinomas of the lung in detail, but also revealed that histologic subtypes of lung carcinomas were closely related to the prognosis of patients with those carcinomas. Large cell neuroendocrine carcinomas are common tumors that are now more frequently diagnosed by pathologists as recognition of LCNEC improves. Since the first report of LCNEC in 1991, many authors have reported that LCNECs are aggressive tumors and that patients with LCNECs have a very poor prognosis. Although LCNEC is categorized as a variant of large cell carcinoma, the biological behaviors of LCNEC tumors resemble those of small cell lung carcinomas, and LCNEC reveals the feature of a high-grade neuroendocrine tumor. Because patients with LCNEC have a poor prognosis, surgery alone is not sufficient. Multimodality therapies (including adjuvant chemotherapy) appear to be promising for the improvement of the prognosis in patients with LCNEC, even if the pathologic stage is IA, and should be evaluated further in larger multi-institutional trials.

p53 immunostaining is correlated with reduced survival and is not correlated with gene mutations in resected pulmonary large cell carcinomas

Malignancy of pulmonary large cell carcinomas (LCC) increases from classic LCC through LCC with neuroendocrine morphology (LCCNM) to large cell neuroendocrine carcinomas (LCNEC). However, the histological classification has sometimes proved to be difficult. Because the malignancy of LCC is highly dependent on proteins with functions in the cell cycle, DNA repair, and apoptosis, p53 has been targeted as a potentially useful biological marker. p53 mutations in lung cancers have been shown to result in expression and protein expression also occurs in the absence of mutations. To validate the importance of both p53 protein expression (by immunostaining) and p53 gene mutations in lung LCC (by PCR-single strand conformational polymorphism analysis of exons 5, 6, 7, and 8) and to study their relationships with clinical factors and sub-classification we investigated the correlation of p53 abnormalities in 15 patients with LCC (5 classic LCC, 5 LCNEC, and 5 LCCNM) who had undergone resection with curative intent. Of these patients, 5/15 expressed p53 and none had mutant p53 sequences. There was a negative survival correlation with positive p53 immunostaining (P = 0.05). After adjustment for stage, age, gender, chemotherapy, radiotherapy, and histological subtypes by multivariate analysis, p53 expression had an independent impact on survival. The present study indicates that p53 assessment may provide an objective marker for the prognosis of LCC irrespective of morphological variants and suggests that p53 expression is important for outcome prediction in patients with the early stages of LCC. The results reported here should be considered to be initial results because tumors from only 15 patients were studied: 5 each from LCC, LCNEC and LCCNM. This was due to the rarity of these specific diseases.

Regulation of the G1/S phase of the cell cycle and alterations in the RB pathway in human lung cancer

The retinoblastoma (RB)-Cyclin (CCN)D1-p16 cell cycle pathway has a crucial role in lung tumorigenesis. Impairment of the RB pathway has been shown to occur in almost all lung tumors. A deregulation at any level of this core RB pathway seems to make cells insensitive to the mitogenic signaling that is required for cell cycle progression. To date, almost all participants in this pathway have been shown to be altered to a various degree in lung tumors. Some of the alterations are mutually exclusive, including RB and p16INK4A . In small cell lung cancer, the RB tumor suppressor gene is inactivated in almost 90% of the tumors, whereas in non-small cell lung cancer, the cyclin-dependent kinase (CDK)4 inhibitor p16INK4A is inactivated in 40-60% of the tumors. Many mechanisms may be responsible for activating the RB-Cyclin D1 pathway, including activating (CDK4) and inactivating mutations (p16INK4A ), deletions (RB and p16INK4A ), amplifications (CCND1 and CDK4), silencing methylation (p16INK4A and RB), and hyper-phosphorylation (RB). As some of these alterations, such as p16INK4A methylation, can also be detected in bronchial lavage and serum, they could potentially serve as useful markers for the early detection of lung cancer. This review summarizes recent experiments describing the variable roles of key-player molecules of the RB pathway and different mechanisms by which the RB pathway can be altered in lung cancer.

Epigenetic silencing of 14-3-3sigma in cancer

The 14-3-3sigma gene is a direct target of the p53 tumor suppressor and its product inhibits cell cycle progression. Recently, a proteomic analysis revealed that 14-3-3sigma regulates additional cellular processes relevant to carcinogenesis, as migration and MAP-kinase signalling. The expression of 14-3-3sigma is down-regulated by CpG methylation in several types of human cancer, among them prostate, lung, breast and several types of skin cancer. The epigenetic inactivation of 14-3-3sigma occurs at an early stage of tumor development and may allow evasion from senescence and promote genomic instability. In the future the detection of CpG methylation of 14-3-3sigma may be used for diagnostic and prognostic purposes.

Large cell carcinoma with neuroendocrine morphology of the lung

We experienced a surgical case of large cell carcinoma with neuroendocrine morphology (LCCNM) of the lung. A 76-year-old man was admitted to our hospital because a routine chest X-ray examination had revealed a nodular shadow in the left lung field. 18F-fluorodeoxyglucose positron emission tomography showed accumulation of fluorodeoxyglucose in an area corresponding to the shadow. Transbronchial lung biopsy failed to give a definitive diagnosis, therefore open lung biopsy was performed because of suspected lung cancer. Needle biopsy was performed, and the tumor was diagnosed as large cell neuroendocrine carcinoma by rapid intraoperative pathological examination. As sampling of hilar lymph nodes revealed no metastasis, left upper segmentectomy was performed for severe obstructive pulmonary disease. Immunohistochemical examination finally diagnosed the tumor as LCCNM. The patient is doing well without recurrence at ten months after surgery.

Identification of tumor suppressor loci on the long arm of chromosome 5 in pulmonary large cell neuroendocrine carcinoma

BACKGROUND

A recent cytogenetic analysis of non-small cell lung cancer revealed hot-spot regions for deletion on the long arm of chromosome 5 and suggested the existence of putative tumor suppressor genes in that region. However, similar studies on genetic alterations in large cell neuroendocrine carcinoma (LCNEC) have been very limited. To our knowledge, this is the first report to screen for the loss of heterozygosity (LOH) and to examine the location of putative tumor suppressor genes on chromosome 5q in LCNEC.

OBJECTIVES

To identify tumor suppressor loci on chromosome 5q in LCNEC by microsatellite analysis.

PATIENTS AND METHODS

Microsatellite instability and LOH in tumor and normal tissue samples from 13 patients with LCNEC, who had undergone surgical resections, were analyzed by polymerase chain reaction using a panel of 19 microsatellite DNA markers spanning chromosome 5q.

RESULTS

LOH was found in all of the 13 tumors (100%) in at least one informative marker tested. The following four common minimally deleted regions were noticed on chromosome 5q: 5q14.3-q21.1; 5q22.2-q23.1; 5q23.3-q33.2; and 5q35.1-q35.2. Three of 13 individual tumors (23.1%) exhibited shifted bands for at least one of the tested microsatellite markers. Shifted bands occurred in 6 of 224 loci (2.7%) tested.

CONCLUSION

These data suggest the presence of at least four tumor suppressor loci on chromosome 5q in LCNEC, and further investigations into cloning candidate tumor suppressor genes are warranted.