Pulmonary Large-cell Carcinoma Research Articles

Characterization of two transcriptomic subtypes of marker-null large cell carcinoma of the lung suggests different origin and potential new therapeutic perspectives

Pulmonary large cell carcinoma (LCC) is an undifferentiated neoplasm lacking morphological, histochemical, and immunohistochemical features of small cell lung cancer, adenocarcinoma (ADC), or squamous cell carcinoma (SCC). The available molecular information on this rare disease is limited. This study aimed to provide an integrated molecular overview of 16 cases evaluating the mutational asset of 409 genes and the transcriptomic profiles of 20,815 genes. Our data showed that TP53 was the most frequently inactivated gene (15/16; 93.7%) followed by RB1 (5/16; 31.3%) and KEAP1 (4/16; 25%), while CRKL and MYB genes were each amplified in 4/16 (25%) cases and MYC in 3/16 (18.8%) cases; transcriptomic analysis identified two molecular subtypes including a Pure-LCC and an adenocarcinoma like-LCC (ADLike-LCC) characterized by different activated pathways and cell of origin. In the Pure-LCC group, POU2F3 and FOXI1 were distinctive overexpressed markers. A tuft cell-like profile and the enrichment of a replication stress signature, particularly involving ATR, was related to this profile. Differently, the ADLike-LCC were characterized by an alveolar-cell transcriptomic profile and association with AIM2 inflammasome complex signature. In conclusion, our study split the histological marker-null LCC into two different transcriptomic entities, with POU2F3, FOXI1, and AIM2 genes as differential expression markers that might be probed by immunohistochemistry for the differential diagnosis between Pure-LCC and ADLike-LCC. Finally, the identification of several signatures linked to replication stress in Pure-LCC and inflammasome complex in ADLike-LCC could be useful for designing new potential therapeutic approaches for these subtypes.

Factors for incidence risk and prognosis of synchronous brain metastases in pulmonary large cell carcinoma patients: a population-based study

BackgroundPatients with pulmonary large cell carcinoma (LCC) have a high incidence of synchronous brain metastases (SBM) and a poor prognosis. Our study was to evaluate the predictive and prognostic value of the clinical characteristics of pulmonary LCC patients with SBM at initial diagnosis by utilizing the Surveillance, Epidemiology, and End Results (SEER) database.MethodsLCC patients, diagnosed from 2010 to 2019, were identified from the latest SEER database which was released in April 2022. Logistic regression and Cox regression were used to identify the predictive and prognostic factors for LCC patients with SBM. Propensity score matching (PSM) and Kaplan–Meier analyses were applied to assess different therapy modalities.ResultsA total of 1375 LCC patients were enrolled in this study and 216 (15.7%) of them had SBM at the initial diagnosis. The median overall survival (OS) of LCC patients with SBM was 4 months. Multivariate Cox regression identified age 60–79 (OR 0.57; 95% CI 0.41–0.78; p < 0.001), age ≥ 80 (OR 0.23; 95% CI 0.12–0.45; p < 0.001) and bone metastases (OR 1.75; 95% CI 1.22–2.51; p < 0.001) as significant independent predictors for developing SBM. Multivariable Cox regression revealed that age 60–79, T stage, bone metastases and chemotherapy were independent prognostic factor for OS. The surgery combined with chemotherapy and radiotherapy group, in which all patients were N0 stage and had no other site-specific metastases, exhibited the best median OS of 15 months.ConclusionsLCC patients with age < 60 or bone metastases were more likely to have SBM at initial diagnosis. Age, T stage, bone metastases and chemotherapy were independent prognostic factors for OS of LCC patients with SBM. Highly selected patients might achieve the best survival benefit from surgery combined with chemotherapy and radiotherapy.

Two Cases of Retroperitoneal Fibrosis During Anti-programmed Cell Death 1 Antibody Treatment

Background. Retroperitoneal fibrosis is characterized by fibrosis around the abdominal aorta and iliac arteries. Two-thirds of reported cases had idiopathic causes. Idiopathic retroperitoneal fibrosis is thought to result from a local inflammatory reaction to antigens in the atherosclerotic plaques of the abdominal aorta. Therefore, it is thought that idiopathic retroperitoneal fibrosis may be a manifestation of a systemic autoimmune or inflammatory disease. In contrast, anti-programmed cell death 1 (anti-PD-1) antibodies may overexpress innate immunity. There have been only two case reports on retroperitoneal fibrosis during anti-PD-1 antibody treatment. We encountered two cases of retroperitoneal fibrosis during anti-PD-1 antibody treatment. Cases. Case 1 involved a 57-year-old man who experienced recurrence of squamous cell lung carcinoma after resection. More than 75% of his cancer cells were positive for programmed cell death ligand 1 (PD-L1). He experienced urinary urgency after one year and six months of nivolumab treatment. Computed tomography revealed a homogeneous plaque that was isodense with muscle surrounding the abdominal aorta and iliac arteries. Positron emission tomography revealed the accumulation of fluorodeoxyglucose at the same site. The serum IgG4 level was normal. Although a biopsy specimen was not obtained, the patient was diagnosed with retroperitoneal fibrosis. The patient was treated with steroids. Case 2 involved a 64-year-old man with pulmonary large cell carcinoma. An analysis of the cancer cells revealed that 50-74% of the cells were positive for PD-L1. Lower back pain appeared after one year and 11 months of pembrolizumab treatment. Computed tomography revealed right hydronephrosis and homogeneous plaque on the right side of the abdominal aorta. Although a biopsy specimen was not obtained, the patient was diagnosed with retroperitoneal fibrosis. The patient improved once with steroids but relapsed. Conclusion. We hypothesized that the administration of anti-PD-1 antibodies may have affected the onset of retroperitoneal fibrosis.

The Clinical Characteristics and Treatments for Large Cell Carcinoma Patients Older than 65 Years Old: A Population-Based Study.

Pulmonary large cell carcinoma, a type of non-small cell lung cancer (NSCLC), is a rare neoplasm with poor prognosis. In this study, our aim was to investigate the impact of radiation sequences with surgery for stage III/IV LCC patients between different age groups, especially in the elderly patients. The patients with LCC and other types of NSCLC in the Surveillance, Epidemiology and End Results (SEER) database from 2004 to 2015 were retrospectively analyzed. Then we divided the LCC patients into two age groups: &lt;65 years old group and ≥65 years old group. Propensity score method (PSM) was used to control potential differences between different groups. The overall survival (OS) of LCC patients and other types of NSCLC patients were evaluated by Kaplan-Meier analysis. Univariate and multivariate Cox regression analysis were employed to explore the independent risk factors of OS. The forest plots of HRs for OS were generated to show the above outcomes more visually. In total, 11,349 LCC patients and 129,118 other types of NSCLC patients were enrolled in this study. We divided LCC patients into &lt;65 years old group (4300) and ≥65 years old group (7049). LCC patients was more common in whites (81.4%), males (58.3%), elderly (≥65 years old: 62.1%), east regions (52.7%), upper lobe (51.6%), right-origin of primary (55.4%), with advanced grade (54.2%) or stage (76.7%). After PSM, Kaplan-Meier analysis and multivariate Cox analysis showed significantly worse survival prognosis for LCC patients compared to other types of NSCLC, especially in the group ≥65 years old (HR: 1.230; 95% CI: 1.171-1.291; p &lt; 0.001). For LCC patients, there were some risk survival factors including whites, males, not upper lobe, advanced stage, elder age at diagnosis, bone metastasis, liver metastasis, singled status, no lymphadenectomy, no surgery, and no chemotherapy (p &lt; 0.05). In LCC patients ≥65 years old, radiation after surgery had significantly better impact on overall survival outcomes (HR: 0.863, 95% CI: 0.765-0.973, p = 0.016), whereas radiation prior to surgery (HR: 1.425, 95% CI: 1.059-1.916, p = 0.019) had significantly worse impact on prognosis of patients. In LCC patients &lt;65 years old, radiation sequences with surgery had no significant impact on the OS of patients (p = 0.580), but ≥4 LNRs had significantly survival benefits to prognosis (HR:0.707, 95% CI: 0.584-0.855). Elderly LCC patients had worse malignant tumors than young patients, of which the majority were diagnosed as stage III/IV tumors. Postoperative radiotherapy may achieve a better prognosis for stage III/IV LCC patients older than 65 years old compared to other radiation sequences with surgery.

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

BackgroundLarge 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.Methods31 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.ResultsCompared 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.ConclusionsWe 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.

Large Cell Neuro-Endocrine Carcinoma of the Lung: Current Treatment Options and Potential Future Opportunities.

Large-cell neuroendocrine carcinomas of the lung (LCNECs) are rare tumors representing 1–3% of all primary lung cancers. Patients with LCNEC are predominantly male, older, and heavy smokers. Histologically, these tumors are characterized by large cells with abundant cytoplasm, high mitotic rate, and neuroendocrine immunohistochemistry-detected markers (chromogranin-A, synaptophysin, and CD56). In 2015 the World Health Organization classified LCNEC as a distinct subtype of pulmonary large-cell carcinoma and, therefore, as a subtype of non-small cell lung carcinoma (NSCLC). Because of the small-sized tissue samples and the likeness to other neuroendocrine tumors, the histological diagnosis of LCNEC remains difficult. Clinically, the prognosis of metastatic LCNECs is poor, with high rates of recurrence after surgery alone and overall survival of approximately 35% at 5 years, even for patients with early stage disease that is dramatically shorter compared with other NSCLC subtypes. First-line treatment options have been largely discussed but with limited data based on phase II studies with small sample sizes, and there are no second-line well defined treatments. To date, no standard treatment regimen has been developed, and how to treat LCNEC is still on debate. In the immunotherapy and targeted therapy era, in which NSCLC treatment strategies have been radically reshaped, a few data are available regarding these opportunities in LCNEC. Due to lack of knowledge in this field, many efforts have been done for a deeper understanding of the biological and molecular characteristics of LCNEC. Next generation sequencing analyses have identified subtypes of LCNEC that may be relevant for prognosis and response to therapy, but further studies are needed to better define the clinical impact of these results. Moreover, scarce data exist about PD-L1 expression in LCNEC and its predictive value in this histotype with regard to immunotherapy efficacy. In the literature some cases are reported concerning LCNEC metastatic patients carrying driver mutations, especially EGFR alterations, showing targeted therapy efficacy in this setting of disease. Due to the rarity and the challenging understanding of LCNEC, in this review we aim to summarize the management options currently available for treatment of LCNEC.

Lethal multiple colon necrosis and perforation due to fulminant amoebic colitis: a surgical case report and literature review

BackgroundAmoebiasis caused by the protozoan species Entamoeba histolytica rarely develops into fulminant amoebic colitis (FAC), but when it does, it shows an aggressive clinical course including colonic perforation, necrotizing colitis, and high mortality. Surgical treatment for FAC patients should be carried out urgently. However, even after surgery, the mortality rate can be 40–50%. Although FAC is one of the most unfavorable surgical diseases with a poor prognosis, there are a few reports on the perioperative diagnosis and management of FAC based on autopsy findings. We herein report the surgical case of a 64-year-old man who developed multiple colon necrosis and perforation due to FAC. A detailed autopsy revealed FAC as the cause of death. Additionally, we reviewed the existing literature on FAC patients who underwent surgery and followed their perioperative diagnosis and management.Case presentationA 64-year-old man presented with anorexia, diarrhea, and altered consciousness on arrival to our hospital. Computed tomography revealed a large mass in the upper right lobe of his lung, and the patient was admitted for close investigation. Bloody diarrhea, lower abdominal pain, and hypotension were observed soon after admission. Urgent abdominal contrast-enhanced computed tomography scan revealed extensive intestinal ischemia, intestinal pneumatosis, and free intra-abdominal gas. The preoperative diagnosis was bowel necrosis and perforation with intussusception of the small intestinal tumor. Emergency subtotal colectomy and enterectomy were performed soon after the contrast-enhanced computed tomography. He was taken to an intensive care unit after surgery. However, he could not recover from sepsis and died with disseminated intravascular coagulation and multiple organ failure on the 10th-day post-surgery. A histopathological examination of the resected colon showed transmural necrosis and massive amoebae invasion. He was diagnosed with FAC. An autopsy revealed that he had developed pulmonary large cell carcinoma with small intestinal metastasis. The death was caused by intestinal ischemia, necrosis and the perforation of the residual bowel caused by amoebae invasion.ConclusionsSince FAC is a lethal disease with a high mortality rate and antibiotic therapies except metronidazole are ineffective, preoperative serological testing and perioperative metronidazole therapy in FAC patients can dramatically improve their survival rates.

Atypical and incomplete pulmonary hypertrophic osteoarthropathy in the left distal femur: a case report

BackgroundPulmonary hypertrophic osteoarthropathy (PHO) is a rare paraneoplastic syndrome that mainly occurs in patients with lung cancer. Most symptoms occur symmetrically, and unilateral symptoms without clubbing are infrequent. This report presents the case of a rare atypical symptom that was highly suspected of being PHO.Case presentationA 77-year-old woman with swelling and severe pain in the left femur for 2 months was referred to our hospital. Radiography revealed a remarkably osteogenic thickening and sclerotic lesion in her distal femur. Preliminary diagnoses of malignant bone tumor and hematological tumor were made based on laboratory test results, radiological examination, and clinical manifestation. A needle biopsy was performed, which ruled out the diagnosis of malignant bone tumors. A low-grade bone tumor was still suspected. After that, en bloc resection was performed, followed by replacement of the femur with a mega-prosthesis. Pathological analysis revealed no malignant tumor cells, and immunohistochemical staining for CDK4 and MDM2 yielded negative results. Meanwhile, pulmonary large cell carcinoma was identified on biopsy. Based on published studies, a diagnosis of atypical PHO was made according to clinical and imaging manifestations.ConclusionsThis is an infrequent case of PHO with unilateral symptoms in the left femur. When clinical manifestations and radiological findings are inconsistent with the pathological results, the possibility of benign lesions with malignant clinical manifestations or imaging features should be carefully considered.

Clinical characteristics and prognosis of pulmonary large cell carcinoma: A population-based retrospective study using SEER data.

BackgroundPulmonary large cell carcinoma (LCC) is an infrequent neoplasm with a poor prognosis. This study explored the clinical characteristics and survival prognostic factors of LCC patients.MethodsPatient data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Chi‐square tests or rank‐sum tests were used to compare differences in clinical characteristics. Log‐rank tests, univariate, and multivariate analyses were performed to investigate the independent factors of survival. Analyses of stage I–IV patients were performed to further explore the optimal treatment.ResultsIn total, 3197 LCC patients were included in this analysis. Compared with other non‐small cell lung cancers (NSCLCs), there was a worse overall survival (OS) from LCC. LCC was more common in males, over age 60 and in the upper lobe. A total of 73.6% of patients were stage III/IV. The median OS of stage I–IV patients was 42 months, 22 months, 11 months, and three months, respectively. The elderly, males, later stage, and main bronchus location, or overlapping lesions were risk factors for survival prognosis. In stage I–III patients, treatment including surgery could significantly reduce the risk of death by 60% at least compared with no therapy. Surgery was still beneficial for stage IV patients, and the hazard ratio (HR) compared with no therapy was 0.462 (P = 0.001).ConclusionsOur study concluded that LCC has unique clinical features, and that age, sex, primary site, stage, and treatment are significantly related to OS. Surgery based comprehensive treatments are effective for LCC.Key points Significant findings of the study In stage IV patients, chemotherapy or radiotherapy combined with surgery could further improve survival. When surgical resection involved more than one lobe, it may be beneficial for survival prognosis. What this study adds LCC patients were principally male and over age 60, with later stages and poor survival prognosis. Age, sex, stage, primary site and therapy are closely related to survival.

Adjuvant chemotherapy improves the prognosis of early stage resectable pulmonary large cell carcinoma: analysis of SEER data.

Pulmonary large cell carcinoma (LCC) is a poorly differentiated and rare tumor with dismal outcome, and there are no recommended treatments for LCC. Little is known about the efficacy of postoperative chemotherapy in patients with early stage LCC. The patients with early stage I/II LCC in the Surveillance, Epidemiology and End Results (SEER) database between 2004 and 2015 were retrospectively reviewed. The overall survival (OS) of patients with LCC at different stages and treatments were evaluated by Kaplan-Meier analysis with log-rank test. Univariate and multivariate Cox proportional risk regression analysis were employed to determine the independent risk factors of OS. Finally, a nomogram was constructed to predict the 1 -, 3- and 5-year OS of early stage LCC patients. A total of 1,099 pulmonary LCC cases were included in this study. 71.8% of patients were over 60 years old, and 66.7% of the tumor lesions located in the upper lobe, followed by the lower lobe (25.7%). Meanwhile, the majority of tumors showed poor differentiation (96.1%). The median OS of surgical patients with or without post-operative adjuvant chemotherapy was 61 and 47 months, respectively. Post-operative chemotherapy was associated with better OS (HR: 0.805; 95% CI: 0.676-0.959, P=0.020). For patients with tumor size >3 cm or IB stage tumor, the prognosis of postoperative chemotherapy was better than that of patients without chemotherapy. Multivariate Cox analysis revealed the age, stage and treatments were independent risk factors of OS for early stage LCC. The nomogram had a calibration index of 0.581. The incidence of LCC was high in the elderly, and it generally had poor differentiation. Post-operative chemotherapy is strongly recommended for patients with LCC at stage IB or higher.

Characterization of a Novel Mouse Model of Spontaneous Human Lung Cancer Metastasis

To identify new strategies against lung metastasis and understand the underlying mechanisms, a highly metastatic pulmonary large cell carcinoma cell line model (801BL) was established through two rounds of in vivo selection using a nude mouse xenograft model. Satellite tandem repeat (STR) analysis confirmed the same genomic background of the newly established metastatic cell line 801BL as the non-metastatic 801C and low-metastatic 801D counterparts. Our study showed that 100% of mice (8 out of 8) injected subcutaneously with 801BL cells developed lung metastatic tumors, while none of the mice injected with 801C cells had lung metastasis (p&lt;0.0001). Highly metastatic 801BL cells showed alterations in morphology and invasion capability when compared with 801C and/or 801D cell lines A comparative proteomic analysis between 801BL and 801C followed by bioinformatics analysis revealed significant alterations in several dominant cell signalling networks in the highly metastatic cell line. Western blot confirmed the proteomic findings for several proteins from each signalling network. Since the highly metastatic cell line and its non-metastatic counterpart share the identical genetic background, this model provides a powerful tool for study of the mechanisms underlying lung cancer metastasis.

The Landscape of Actionable Molecular Alterations in Immunomarker-Defined Large-Cell Carcinoma of the Lung

IntroductionPatients with pulmonary large-cell carcinoma (LCC) have poor prognosis and limited treatment options. The identification of clinically actionable molecular alterations helps to guide personalized cancer treatment decisions. Patients and MethodsA consecutive cohort of 789 resected NSCLC cases were reviewed. Fifty-nine NSCLC cases lacking morphologic differentiation, accounting for 7.5% of all resected NSCLCs, were identified and further characterized by immunohistochemistry according to the 2015 WHO lung tumor classification. Molecular alterations were investigated by multiple technologies including target capture sequencing, immunohistochemistry, and fluorescence in situ hybridizations. ResultsOf 59 NSCLC cases lacking morphologic differentiation, 20 (33.9%) were reclassified as adenocarcinoma (LCC-AD), 14 (23.7%) as squamous cell carcinoma (LCC-SqCC), and 25 (42.4%) as LCC-Null. Approximately 92% of LCC-Null, 95% of LCC-AD, and 86% of LCC-SqCC harbored clinically relevant alterations. Alterations characteristic of adenocarcinoma (EGFR, KRAS, ALK receptor tyrosine kinase [ALK], ROS1, and serine/threonine kinase 11 [STK11]) were detected in the LCC-AD subgroup but not in LCC-SqCC, whereas squamous-lineage alterations (phosphatidylinositol-4,5-biphosphate 3-kinase catalytic subunit alpha [PIK3CA], SRY-box 2 [SOX2], fibroblast growth factor receptor 1 [FGFR1], and AKT1) were detected in the LCC-SqCC subgroup but not in the LCC-AD group. Although some LCC-Null tumors displayed a genetic profile similar to either adenocarcinoma or squamous-cell carcinoma, more than half of the LCC-Null group were completely devoid of recognizable lineage-specific genetic profiles. High programmed death ligand 1 expression and high frequency of cell cycle regulatory gene alterations were found in the LCC-Null group offering alternative options of targeted therapy. ConclusionsThis comprehensive molecular study provided further insight into the genetic architecture of LCC. The presence of clinically actionable alterations in a majority of the tumors allowed personalized treatment to emerge.

P3.02-097 Clinicopathological Features and Genetic Landscape of Pulmonary Large Cell Carcinoma under 2015 WHO Classification of NSCLC

Pulmonary large cell carcinoma (LCC) was re-defined by 2015 WHO classification of non-small cell lung cancer (NSCLC) by excluding the tumors with adenocarcinoma, squamous and neuroendocrine features. The clinicopathological features and genetic landscape of pulmonary large cell carcinoma (LCC) with new classification were barely investigated.

Clinicopathological and genetic characteristics of pulmonary large cell carcinoma under 2015 WHO classification: a pilot study.

Pulmonary large cell carcinoma (LCC) was re-defined under the 2015 WHO classification criteria. However, the clinicopathological features and genetic mutation statuses of Chinese LCC patients based on the new classification have rarely been investigated. Twenty-four Chinese surgically resected LCC patients previously diagnosed under the 2004 WHO criteria were re-classified under the 2015 WHO criteria. Genetic analysis was performed using next-generation sequencing of 46 cancer-related genes. The correlation of clinicopathological and genetic data was further analyzed. Eight patients were re-defined as LCCs, and 16 patients were defined as non-LCCs under the refined criteria. All LCC patients were male, and 7 patients were smokers. No significant differences in age, gender, smoking status, primary site, TNM staging and overall survival were observed between the LCC and non-LCC patients under the refined criteria. Four of the 8 LCC patients presented TP53 mutations, and no somatic mutations were detected in the other 4 LCCs under the refined criteria. For the 16 non-LCCs, not only TP53 and KRAS but also EGFR, KIT, PIK3CA, PTEN, IDH1, APC, ATM and BRAF mutations were also observed. In addition, LCCs without TP53 mutations did not present any gene mutations under the 2004 or 2015 WHO criteria. Importantly, the patients with TP53 mutation exhibited a trend with a worse survival outcome at the time of follow-up. The new WHO diagnosis criteria have superior performance in precise molecular classification for LCC patients.

P1.02-075 Analysis of Driver Genes Alteration and Clinicopathological Features in Pulmonary Marker-Null Large Cell Carcinoma

Pulmonary large cell carcinoma (LCC) was an undifferentiated and marker-null non-small cell lung cancer (NSCLC) according to 2015 WHO classification criteria. However, there are few studies presented molecular analysis and clinical features of this subtype. The aim of this study is to investigate profile of driver mutations and clinicopathological features of marker-null LCC. From January 2008 to February 2015, 327 cases of surgically resected primary large cell carcinoma diagnosed by H&E staining were enrolled from Shanghai pulmonary hospital affiliated to Tongji university (Lymphoepithelioma-like carcinoma and large cell neuroendocrine carcinoma were excluded with typical morphologic features). Large cell carcinoma was re-classificated with a panel of immunophenotypic markers (adenocarcinoma [ADC]-specific, thyroid transcription factor-1, napsin A and anti-diastase PAS staining; squamous cell carcinoma [SQCC]-specific, cytokeratin5/6, and p40; epithelial mesenchymal transition [EMT], cytokeratin, vimentin and ZEB1; neuroendocrine differentiation, synaptophysin and CD56). Molecular analysis (EGFR, KRAS, BRAF, ROS1, ALK and PIK3CA) and immunomarker PD-L1 of marker-null LCC were detected by ARMS method and immunohistochemistry, respectively. 113 cases (113/327, 34.6%) were re-diagnosed as ADC with solid growth pattern, which showed TTF-1 positive rate 59.3% (67/113, 59.3%), Napsin A positive rate 82.3% (93/113，82.3%) (P<0.001) and positive PAS staining (5/113, 4.4%). 47 (47/327, 14.4%) cases were re-classificated as SQCC, which positively expressed p40 (44 cases, 44/47, 93.6%) and CK5/6 (31 cases, 31/47, 66%)( P<0.01). 5 (5/327, 1.5%) cases of large cell neuroendcrine carcinoma showed both neuroendocrine morphological feature and CD56、Syn expression. 26 (26/327, 8.0%) were redefined as sarcomatoid carcinoma expressed cytokeratin, vimentin and ZEB1. 136 (136/327, 41.6%) cases of marker-null LCC were diagnosed for lack of specific markers expression. 30 (30/136, 22.1%) cases of marker-null LCC showed PD-L1 positive. Driver genes alteration were found in 3 cases from 30 cases marker-null LCC, including KRAS (n=1), BRAF (n=1) and PIK3CA (n=1). Clinicopathological characteristics indicated that LCC patients were older and more likely to be male nonsmokers. Large cell carcinoma was differentially diagnosed by combining with undifferentiated NSCLC morphology and marker-null features. Driver genes mutation testing may significantly impact on the choice of targeted therapy.

Dissecting Pulmonary Large-Cell Carcinoma by Targeted Next Generation Sequencing of Several Cancer Genes Pushes Genotypic-Phenotypic Correlations to Emerge

Little is known about genotypic and phenotypic correlations in undifferentiated large-cell carcinoma (LCC) of the lung. Thirty LCC were dissected by unsupervised targeted next generation sequencing analysis for 50 cancer-associated oncogenes and tumor suppressor genes. Cell differentiation lineages were unveiled by using thyroid transcription factor-1 (TTF1) for adenocarcinoma (ADC) and p40 for squamous cell carcinoma (SQC), dichotomizing immunohistochemistry (IHC) results for TTF1 as negative or positive (whatever its extent) and for p40 as negative, positive, or focal (if <10% of reactive tumor cells). Three LCC were wild type (all TTF1+/p40-), whereas the remaining 27 (90%) tumors had at least one gene mutation. Twenty-four cases featuring TTF1+/p40-, TTF1+/p40±, TTF1-/p40±, or TTF1-/p40- phenotypes comprised ATM, BRAF, CDKN2A, EGFR, ERBB4, FBXW7, FLT3, KRAS, NRAS, PIK3CA, PTPN11, RET, SMAD4, SMO, STK11, or TP53 mutations in keeping with ADC lineage, whereas three tumors showing TTF1-/p40+ phenotype harbored TP53 only and no ADC-related mutations in keeping with SQC lineage. Single, double, triple, quadruple, and quintuple mutations occurred in 16, 6, 2, 2, and 1 patient, respectively. The occurrence of three mutations or more but not any immunohistochemistry categorization predicted shorter overall survival (OS, p = 0.001) and disease-free survival (DFS, p = 0.007), independent of age, sex, and tumor stage. Albeit preliminary also because of the relatively small number of LCC under evaluation, this targeted next generation sequencing study, however, revealed gene mutation heterogeneity in LCC with some genotypic-phenotypic correlations. Negativity or focal occurrence of p40 made SQC diagnosis unlikely on molecular grounds, but suggested ADC confirming validity of the axiom "no p40, no squamous."

Next-Generation Sequencing of a Cohort of Pulmonary Large Cell Carcinomas Reclassified by World Health Organization 2015 Criteria.

The classification of pulmonary large cell carcinoma has undergone a major revision with the recent World Health Organization (WHO) 2015 Classification. Many large cell carcinomas are now reassigned to either adenocarcinoma with solid pattern or nonkeratinizing squamous cell carcinoma based on immunopositivity for adenocarcinoma markers or squamous cell carcinoma markers, respectively. Large cell carcinomas that are negative for adenocarcinoma and squamous cell carcinoma immunomarkers are now classified as large cell carcinoma with null immunohistochemical features (LCC-N). Although a few studies investigated the mutation profile of large cell carcinomas grouped by immunostain profile before the publication of the new WHO classification, investigation of tumors previously diagnosed as large cell carcinoma and reclassified according to the 2015 WHO classification has not, to our knowledge, been reported. To determine the mutation profiles of pulmonary large cell carcinomas reclassified by WHO 2015 criteria. Archival cases of non-small cell lung carcinoma with large cell carcinoma morphology (n = 17) were reclassified according to 2015 WHO criteria. To determine mutation profile, we employed Ion Torrent (Life Technologies, Carlsbad, California)-based next-generation sequencing (50 genes; more than 2800 mutations) in addition to real-time quantitative reverse transcription polymerase chain reaction for ALK translocation detection. Two of 17 cases (12%) were reclassified as LCC-N, and both had mutations-BRAF D594N in one case and KRAS G12C in the other case. Seven of 17 cases (41%) were reclassified in the adenocarcinoma with solid pattern group, which showed one KRAS G12C and one EGFR E709K + G719C double mutation in addition to mutations in TP53. Eight of 17 cases (47%) were reclassified in the nonkeratinizing squamous cell carcinoma group, which showed mutations in PIK3CA, CDKN2A, and TP53. No ALK translocations or amplifications were detected. The adenocarcinoma with solid pattern group showed mutations typical of adenocarcinoma, whereas the nonkeratinizing squamous cell carcinoma group showed mutations typical of squamous cell carcinoma. Both LCC-N cases had mutations associated with adenocarcinoma, supporting the hypothesis that LCC-N is related to adenocarcinoma.

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.

急性呼吸不全で死亡した顆粒球コロニー刺激因子産生肺大細胞癌の1剖検例

急性呼吸不全で死亡した顆粒球コロニー刺激因子産生肺大細胞癌の1剖検例

Large cell carcinoma of the lung: clinically oriented classification integrating immunohistochemistry and molecular biology

This study aimed at challenging pulmonary large cell carcinoma (LLC) as tumor entity and defining different subgroups according to immunohistochemical and molecular features. Expression of markers specific for glandular (TTF-1, napsin A, cytokeratin 7), squamous cell (p40, p63, cytokeratins 5/6, desmocollin-3), and neuroendocrine (chromogranin, synaptophysin, CD56) differentiation was studied in 121 LCC across their entire histological spectrum also using direct sequencing for epidermal growth factor receptor (EGFR) and v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations and FISH analysis for ALK gene translocation. Survival was not investigated. All 47 large cell neuroendocrine carcinomas demonstrated a true neuroendocrine cell lineage, whereas all 24 basaloid and both 2 lymphoepithelioma-like carcinomas showed squamous cell markers. Eighteen out of 22 clear cell carcinomas had glandular differentiation, with KRAS mutations being present in 39 % of cases, whereas squamous cell differentiation was present in four cases. Eighteen out of 20 large cell carcinomas, not otherwise specified, had glandular differentiation upon immunohistochemistry, with an exon 21 L858R EGFR mutation in one (5 %) tumor, an exon 2 KRAS mutation in eight (40 %) tumors, and an ALK translocation in one (5 %) tumor, whereas two tumors positive for CK7 and CK5/6 and negative for all other markers were considered adenocarcinoma. All six LCC of rhabdoid type expressed TTF-1 and/or CK7, three of which also harbored KRAS mutations. When positive and negative immunohistochemical staining for these markers was combined, three subsets of LCC emerged exhibiting glandular, squamous, and neuroendocrine differentiation. Molecular alterations were restricted to tumors classified as adenocarcinoma. Stratifying LCC into specific categories using immunohistochemistry and molecular analysis may significantly impact on the choice of therapy.