Multiparametric molecular characterization of pulmonary sarcomatoid carcinoma reveals a nonrandom amplification of anaplastic lymphoma kinase (ALK) gene

Management strategies for primary lung carcinosarcoma: a case study and comprehensive literature review

BACKGROUND

Primary lung carcinosarcoma, characterized by the presence of both carcinoma and sarcoma components, is a rare soft tissue malignancy. Its pathogenesis remains incompletely elucidated, and it exhibits significant resistance to conventional therapeutic interventions, resulting in a dismal prognosis. Consequently, there is currently no established standard treatment protocol for lung carcinosarcoma, leading most clinicians to draw upon their experiences with other tumor types when formulating treatment strategies.

CASE DESCRIPTION

A 56-year-old non-smoking male presented with a progressively enlarging mass in the right cervical region, The diagnosis of lung carcinosarcoma was definitively confirmed through CT-guided biopsy. First-line immunotherapy combined with targeted therapy was ineffective; second-line chemotherapy was effective, chest CT revealed the disappearance of enlarged lymph nodes in the retrosternal area and a significant reduction of pulmonary lesions, but showed signs of brain metastasis. the patient passed away at home on June 27th, 2023 due to sudden onset dyspnea accompanied by loss of consciousness.

LITERATURE REVIEW

A comprehensive literature search for lung carcinosarcoma was conducted across four databases, including PubMed/MEDLINE, Web of Science, Cochrane Library, and Embase, covering the period from 1968 to 2023. A total of 48 patients were included for analysis. Further survival analysis revealed a median survival time of 18 months; adjuvant therapy following surgery significantly improved survival compared to surgery alone and other treatment modalities.

CONCLUSION

Lung carcinosarcoma is an exceptionally rare malignant neoplasm of the lung, and definitive treatment protocols remain elusive. The most effective strategy to enhance prognosis may still entail complete surgical resection of the lesions in conjunction with adjuvant therapy.

Integrated molecular characterization reveals the pathogenesis and therapeutic strategies of pulmonary blastoma

Background

Pulmonary blastoma (PB) is a rare subtype of lung cancer. Currently, the underlying pathogenesis mechanisms of PB have not been fully illustrated, and the therapeutic approach for this entity is limited.

Methods

Whole-exome sequencing (WES), RNA sequencing, and DNA methylation profiling are applied to seven PB patients. Multi-omics data of pulmonary sarcomatoid carcinoma (PSC) and pituitary blastoma (PitB) from previous studies are invoked to illuminate the associations among PB and these malignacies.

Results

We portray the genomic alteration spectrum of PB and find that DICER1 is with the highest alteration rate (86 %). We uncover that DICER1 alterations, Wnt signaling pathway dysregulation and IGF2 imprinting dysregulation are the potential pathogenesis mechanisms of PB. Moreover, we reveal that the integrated molecular features of PB are distinct from PSC, and the molecular characteristics of PB are more similar to PitB than to PSC. Pancancer analysis show that the tumor mutation burden (TMB) and leukocyte fraction (LF) of PB are low, while some cases are positive for PD-L1 or have CD8-positive focal areas, implying the potential applicability of immunotherapy in selected PB patients.

Conclusion

This study depicts the integrated molecular characteristics of PB and offers novel insights into the pathogenesis and therapeutic strategies of PB.

Metastatic Pleomorphic Carcinoma of the Lung with Extensive Chromosomal Rearrangements: An Autopsy Case with a Literature Review

We herein report a 47-year-old man who presented with progressive paraparesis. Imaging revealed a right upper pulmonary nodule, massive bilateral adrenal metastases, thoracolumbar vertebral osteolysis, and subcutaneous nodules. A biopsy of the right buttock nodule revealed a poorly differentiated metastatic carcinoma with high programmed cell death-ligand 1 expression and extensive chromosomal rearrangements. The patient died 10 days after the initiation of pembrolizumab treatment. Autopsy findings confirmed pulmonary pleomorphic carcinoma with extensive metastases. Quantification of chromosomal rearrangements revealed a jump-up mutation from the normal karyotype, followed by a further incremental increase in the degree of deviation.

Defining the needle in a haystack: A compendium of genomic, pathologic, and clinical characteristics of rare pulmonary tumors

A major paradigm shift in the diagnosis, management, and survival outcomes of early and advanced non-small cell lung cancer has transpired over the past few decades in thoracic oncology with the incorporation of molecular testing, targeted therapy, immunotherapy, neoadjuvant, and adjuvant approaches. However, transformation in the management and survival outcomes of rare lung tumors is lacking. Given the scarcity of these tumor types, randomized trials are rarely performed, and treatment is extrapolated from case series, tumor-agnostic trials, or cancers with similar histology. Literature informing the management of rare pulmonary tumors is typically limited to a single histology, unique features, or extraordinary responses to therapy. Few resources detailing genomic characteristics and delineating features of these tumors are available, often resulting in suboptimal treatment. Here, we explore the clinical, histopathologic, genomic features and potential therapies of five rare pulmonary tumors, namely adenosquamous, basaloid squamous, mucoepidermoid, carcinosarcoma, and NUT carcinoma, to build a resource for rare histological subtypes of the lung and emphasize knowledge gaps in the management of these tumors. Our recommendations are based on a comprehensive review of case reports and series, clinical trials, and the "Indiana University Experience."

Preoperative CT findings and prognosis of pulmonary sarcomatoid carcinoma: comparison with conventional NSCLC of similar tumor size

BACKGROUND

Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small cell lung cancer (NSCLC) but differs in terms of treatment strategies compared with conventional-NSCLC (c-NSCLC). However, preoperative CT differentiation between PSC and c-NSCLC remains a challenge. This study aimed to explore the CT findings and prognosis of PSC compared with c-NSCLC of similar tumor size.

METHODS

Clinical data and CT findings of 31 patients with PSC and 87 patients with c-NSCLC were retrospectively analyzed. Clinical data included sex, age, and smoking history. CT findings included tumor size, tumor location, calcification, vacuole/cavity, pleural invasion, mean CT value, and low-attenuation area (LAA) ratio. Kaplan‒Meier curves and log-rank tests were used for survival analysis. A Cox regression model was constructed to evaluate prognostic risk factors associated with overall survival (OS). The Spearman correlation among clinicoradiological outcomes were analyzed.

RESULTS

The mean tumor size of PSC and c-NSCLC were both 5.1 cm. The median survival times of PSC and c-NSCLC were 8 months and 34 months, respectively (P < 0.001). Calcification and vacuoles/cavities were rarely present in PSC. Pleural invasion occurred in both PSC and c-NSCLC (P = 0.285). The mean CT values of PSC and c-NSCLC on plain scan (PS), arterial phase (AP), and venous phase (VP) were 30.48 ± 1.59 vs. 36.25 ± 0.64 Hu (P = 0.002), 43.26 ± 2.96 vs. 58.71 ± 1.65 Hu (P < 0.001) and 50.26 ± 3.28 vs. 64.24 ± 1.86 Hu (P < 0.001), the AUCs were 0.685, 0.757 and 0.710, respectively. Compared to c-NSCLC, PSC had a larger LAA ratio, and the AUC was 0.802, with an optimal cutoff value of 20.6%, and the sensitivity and specificity were 0.645 and 0.862, respectively. Combined with the mean CT value and LAA ratio, AP + VP + LAA yielded the largest AUC of 0.826. The LAA ratio were not independent risk factors for PSC in this study. LAA ratio was negatively correlated with PS (r = -0.29), AP (r = -0.58), and VP (r = -0.66). LAA showed a weak positive correlation with tumor size(r = 0.27).

CONCLUSIONS

PSC has a poorer prognosis than c-NSCLC of similar tumor size. The mean CT value and LAA ratio contributes to preoperative CT differentiation of PSC and c-NSCLC.

Chemotherapy for advanced pulmonary sarcomatoid carcinoma: a population-based propensity score matching study

OBJECTIVES

Pulmonary sarcomatoid carcinoma (PSC) is a rare histological type of non-small cell lung cancer (NSCLC). There are no specific treatment guidelines for PSC. For advanced PSC (stage II-IV), the role of chemotherapy is still controversial. The purpose of this study was to investigate the effect of chemotherapy on the prognosis of advanced PSC.

METHODS

A total of 960 patients with advanced PSC from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2019 were enrolled in this study. To investigate the prognostic factors, the Cox proportional hazard regression model was conducted. A total of 642 cases were obtained after propensity score matching (PSM). The Kaplan‒Meier method was applied to compare overall survival (OS) and cancer-specific survival (CSS).

RESULTS

For all 960 cases included in this study, the Cox proportional hazard model was applied for prognostic analysis. Univariate and multivariate analyses showed that stage, T stage, N stage, M stage, surgery, and chemotherapy were prognostic factors for OS and CSS (P < 0.05). A total of 642 cases were obtained after PSM, with no significant difference between the two groups for all variables. Kaplan‒Meier curves indicated that for OS and CSS, the prognosis was significantly better in the chemotherapy group than in the no-chemotherapy group.

CONCLUSIONS

For advanced PSC, chemotherapy can significantly improve the OS and CSS of patients. Chemotherapy should be an important part of PSC treatment.

Clinicopathological features and prognostic nomogram of giant cell carcinoma of the lung: A population-based study

BACKGROUND

Due to its rarity, the features and prognosis of giant cell carcinoma of the lung (GCCL) are not well defined. The present study aimed to describe the clinicopathological features and prognostic analysis of this rare disease, compare it with lung adenocarcinoma (LAC), further determine the prognostic factors and establish a nomogram.

METHODS

Patients diagnosed with GCCL and LAC were identified from the SEER database between 2004 and 2016. The features and survival between GCCL and LAC were compared in the unmatched and matched cohorts after propensity score matching (PSM) analysis. Univariate and multivariate Cox analyses were used to identify the prognostic factors, and a nomogram was constructed. Area under the curve (AUC), C-index, calibration curve and decision curve analysis (DCA) were used to confirm the established nomogram.

RESULTS

A total of 295 patient diagnosed with GCCL and 149 082 patients with LAC were identified. Compared with LAC, patients with GCCL tend to be younger, male, black and have pathological Grade III/IV GCCL, more proportion of AJCC-TNM-IV, T3/T4 and distant metastases. The 1-, 2- and 5-year OS rates of the patients with GCCL were 21.7%, 13.4% and 7.9%, respectively. The median OS and CSS were 3 and 4 months, respectively. Patients with GCCL had significantly shorter OS and CSS than those with LAC in the unmatched and matched cohorts after PSM. Multivariate Cox analysis demonstrated that T, N and M stages and use of chemotherapy and surgery were independent of survival. Furthermore, we constructed a prognostic nomogram for OS and CSS by using independent prognostic factors. The C-index of OS-specific nomogram is 0.78 (0.74-0.81), and the C-index of CSS-specific nomogram is 0.77 (0.73-0.80). The calibration curve and ROC analysis showed good predictive capability of these nomograms. DCA showed that the nomogram had greater clinical practical value in predicting the OS and CSS of GCCL than TNM staging.

CONCLUSION

GCCL have distinct clinicopathological characteristics and significantly worse clinical outcomes. Prognostic nomograms for overall survival (OS) and CSS were constructed.

PSC subtyping based on TTF-1 and p40 expression reveals distinct molecular characteristics and therapeutic strategies

Pulmonary sarcomatoid carcinoma (PSC) is a unique form of poorly differentiated non-small cell lung cancer (NSCLC) and is notorious for its highly malignant nature and dismal prognosis. To introduce effective treatment for PSC patients, precise subtyping of PSC is demanding. In our study, TTF-1 and P40 immunohistochemistry (IHC) staining were applied to 56 PSC patients with multi-omics data. According to IHC results, we categorized these patients into three subgroups and profiled their molecular contexture using bioinformatic skills. IHC results classified these patients into three subgroups: TTF-1 positive subgroup (n=27), P40 positive subgroup (n=15), and double-negative subgroup (n=14). Spindle cell samples accounted for 35.71% (5/14) of double-negative patients, higher than others (p=0.034). The three subgroups were heterogeneous in the genomic alteration spectrum, showing significant differences in the RTK/RAS pathway (p=0.004) and the cell cycle pathway (p=0.030). The methylation profile of the double-negative subgroup was between the other two subgroups. In similarity analysis, the TTF-1 and p40 subgroups were closely related to LUAD and LUSC, respectively. The TTF-1 positive subgroup had the highest leukocyte fraction (LF) among several cancer types, and the tumor mutation burden (TMB) of the p40 positive subgroup ranked third in the TMB list, suggesting the applicability of immunotherapy for PSC. The study established a new subtyping method of PSC based on IHC results and reveals 3 subgroups with distinct molecular features, providing evidence for refined stratification in the treatment of PSC. This article is protected by copyright. All rights reserved.

The Prognosis of Pulmonary Sarcomatoid Carcinoma: Development and Validation of a Nomogram Based on SEER

Background: The rarity of pulmonary sarcomatoid carcinoma (PSC) and the lack of prospective clinical trials have led to limited knowledge of its clinical characteristics. This study aimed to evaluate the survival and prognostic factors of PSC and to build a nomogram for clinical practice. Methods: Eligible patients diagnosed from 2010 to 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. We compared the clinical characteristics and survival times of PSC patients with those of lung adenocarcinoma (LADC) and lung squamous cell carcinoma (LSCC) patients. We also used univariate and multivariable Cox regression to estimate mortality hazard ratios among patients with PSC, while a visual nomogram was established to judge the prognosis. Discrimination, calibration, clinical utility, and reproducibility were validated by Harrell's concordance index (C-index), the area under the curve (AUC), calibration curves, and decision curve analysis (DCA). Results: A total of 400 PSC patients (0.42%) were identified in the SEER database, whereas 58 474 and 33 637 patients were diagnosed with LADC and LSCC, respectively. Age, T stage, grade, surgery, and radiation were shown to be significant prognostic factors in the Cox regression analyses and were included in the nomogram as predictors. The C-index of the nomogram in the validation set was 0.759. The AUC also demonstrated the good performance of the nomogram, and DCA demonstrated its good clinical applicability. Conclusion: We established a novel nomogram to predict the prognosis of PSC, which can help clinicians make tailored decisions and adjust follow-up management strategies, and can provide accurate and individualized survival predictions.

Rare cutaneous metastasis from sarcomatoid carcinoma of lung

We present the case of a 57-year-old woman diagnosed with stage 4 sarcomatoid carcinoma of the lung who concurrently developed a scalp lesion, thought to be a cyst, which continued to grow and ulcerate. Excision revealed a rare case, only four previously reported in the literature, of metastatic sarcomatoid carcinoma of the lung. While a very unusual case, we would like to emphasise the importance of considering skin metastases when presented with unusual skin lesions, and importantly listening to the patient's concerns, showing empathy and respecting their autonomy and referring to an appropriate specialist when considering the management of what may seem to be a minor skin report.

The genomic and immunologic profiles of pure pulmonary sarcomatoid carcinoma in Chinese patients

PURPOSE

The distribution of genetic mutations differs between pure pulmonary sarcomatoid carcinoma (PSC) and biphasic PSC; however, most of the enrolled cases in previous studies are biphasic PSC. The current study aimed to investigate the genomic and immunologic profiles of pure PSC in the Chinese population.

MATERIALS AND METHODS

Next-generation sequencing analysis of a panel of 1021 genes was performed on surgical specimens of 58 pure PSCs. The tumor mutational burden (TMB) was calculated from 0.69 megabases (Mbs) of sequenced DNA. PD-L1 expression was evaluated by immunohistochemistry. Microsatellite instability (MSI) was evaluated by fluorescence-labeled microsatellite marker polymerase chain reaction followed by capillary electrophoresis fragment size analysis.

RESULTS

The top mutational genes of pure PSC were TP53 (74 %, 43/58), KRAS (24 %, 14/58), SMARCA4 (14 %, 8/58), MET (12 %, 7/58), EGFR (10 %, 6/58), MLL4 (10 %, 6/58), NF1 (10 %, 6/58), NOTCH4 (10 %, 6/58), and TERT (10 %, 6/58). The median TMB was 8.6 mutations/Mb; 37.9 % of cases (22/58) had a TMB > 10 mutations/Mb and 12.1 % of cases (7/58) had a TMB > 20 mutations/Mb. The median TMB was higher in TP53-mutant tumors than in wild-type tumors (10.1 versus 7.2 mutations/Mb, p = 0.019). Thirty-five patients had microsatellite-stable pure PSC, and four patients carried MSI-H tumors. The MSI status was independent of MET exon 14 status. Twenty-six patients (45 %) had PD-L1-positive tumors (≥1%) and 14 (24 %) had high PD-L1 expression (≥50 %).

CONCLUSION

In our cohort, 45 % of patients with pure PSC harbored at least one actionable alteration. More importantly, more than 60 % of patients (65.5 %, 38/58) had either MSI-H, PD-L1-positive, or high-TMB tumors, and these might derive survival benefits from immune checkpoint inhibitors.

Clinicopathological characteristics and prognostic factors of pulmonary sarcomatoid carcinoma: a large population analysis

BACKGROUND

This study was conducted to identify the clinicopathological characteristics and survival outcomes of pulmonary sarcomatoid carcinoma (PSC), and to compare prognostic factors between elderly (≥65 years) and non-elderly (<65 years) patients.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients diagnosed with PSC between 2004 and 2016. The Kaplan-Meier method was used for overall survival (OS) and cancer-specific survival (CSS) analysis. The Cox proportional hazards model was used to detect independent prognostic factors. A propensity score matched (PSM) analysis was conducted to compare OS and CSS in elderly versus non-elderly PSC patients.

RESULTS

A total of 1,039 eligible cases were identified, with a median follow-up of 6 months. The 5-year OS and CSS rates were 12.3% and 18.7%, respectively, and the median survival was 6 months. Multivariate analysis revealed that female (HR =0.750, P<0.004), surgery (HR =0.484, P<0.001), chemotherapy (HR =0.504, P<0.001), and radiation (HR =0.801, P=0.041) were independent favorable prognostic factors. There was a significant difference in the OS and CSS rates between elderly and non-elderly patients after PSM (P=0.007 and P=0.017, respectively). In multivariate analysis, the predictors for OS in the elderly patients were gender, tumor stage, and chemotherapy, whereas in the non-elderly patients, the predictors were tumor stage, chemotherapy, and surgery.

CONCLUSIONS

The PSC patients in our study had poor survival outcomes. Comprehensive treatment, including surgery, chemotherapy, and radiotherapy, could improve patient prognosis. Elderly patients had different clinicopathological characteristics, compared to non-elderly patients.

Strong ALK and PD-L1 positive IHC expression related ALK amplification in an advanced lung sarcomatoid carcinoma: A therapeutic trap?

OBJECTIVES

Immunohistochemistry (IHC) is considered as a screening method for ALK rearrangement thanks to its excellent sensitivity. Strong marking on immunohistochemistry give the go-ahead to start ALK tyrosine kinase inhibitors (ALK TKI). Lack of therapeutic response may then lead to the suspicion of molecular alterations other than ALK rearrangements.

METHODS

We present a patient with strong ALK and PD-L1 positive IHC expression lung sarcomatoid carcinoma with initial life-threatening disease progression after beginning ALK TKI. We also review the literature to summarize ALK amplification clinical features and therapeutic management in lung cancers.

RESULTS

Fluorescence in situ Hybridization (FISH) revealed ALK amplification on the initial anatomopathological samples. Lack of ALK rearrangement and strong PD-L1 positive IHC expression led to the initiation of immune checkpoint inhibitor (ICI) as a second line of treatment, with an excellent response.

CONCLUSION

We demonstrated that IHC positive test, in these cases, must be interpreted with caution. FISH analysis has to be recommended to confirm IHC results in case of unusual phenotype, such as smoker or lung cancer other than adenocarcinoma. Although lung carcinoma with ALK rearrangement seems to be not sensitive to ICI, further investigations should be conducted on other types of ALK molecular alterations. ALK amplifications, as observed in the present case, should not be an impediment to taking into account the PD-L1 marking for the initiation of treatment by immunotherapy.

The role of prognostic nutritional index in the management of pulmonary sarcomatoid carcinoma

Background

Pulmonary sarcomatoid carcinoma is characterized by poor survival rates compared with other non-small cell lung cancer. Prognostic nutritional index has significant prognostic value in many malignant tumors. We conducted this retrospective study to investigate the role of prognostic nutritional index in patients with pulmonary sarcomatoid carcinoma and to determine prognostic factors.

Methods

Of 8176 patients with resected lung cancer in a single high-volume institution between 2008 and 2015, 91 patients with pathologically diagnosed sarcomatoid carcinoma were included in our study and evaluated. Kaplan–Meier analysis and Cox regression analysis were conducted to analyze clinicopathologic data. Subgroup analysis of overall survival (OS) and recurrence-free survival (RFS) among pulmonary sarcomatoid carcinoma patients were also conducted.

Results

Univariable analysis showed that tumor size (P = 0.018 in OS), and P = 0.021 in RFS), tumor stage(P < 0.001 in OS, and P = 0.002 in RFS), nodal metastasis (P < 0.001 in OS, and P < 0.001 in RFS), pathological stage (P < 0.001 in OS, and P < 0.001 in RFS), treatment modality (P = 0.032 in OS, and P = 0.059 in RFS) and PNI (P < 0.001 in OS, and P < 0.001 in RFS), were significant factors of both OS and RFS. In multivariable analysis, for OS, the pathological stage (Hazard ratio (HR) 1.432; 95% confidence interval (95% CI) 1.210–1.695; P < 0.001) and PNI (HR 0.812; 95% CI 0.761–0.865; P < 0.001) were independent prognostic factors. And for RFS, We found PNI as an independent prognostic factor (HR 0.792; 95% CI 0.739–0.848; P < 0.001), and the pathological stage (HR 1.373; 95% CI 1.160–1.625; P < 0.001). In the subgroup of patients with PNI ≥ 49.4, univariable analysis showed treatment modality was a significant factor of overall survival (P = 0.001); multivariable analysis showed patients received postoperative chemotherapy (HR 0.288; 95% CI 0.095–0.874; P = 0.028) or postoperative chemotherapy with targeted therapy (HR 0.148; 95% CI 0.030–0.726; P = 0.019) has better overall survival rates.

Conclusion

The PNI and the pathological TNM stage are independent prognostic factors for pulmonary sarcomatoid carcinoma. PNI is an important indicator for the selection of postoperative adjuvant therapy. Patients with PNI ≥ 49.4 may benefit from postoperative chemotherapy and targeted therapy. We still need further prospective studies to confirm these results.

Genomic origin and intratumor heterogeneity revealed by sequencing on carcinomatous and sarcomatous components of pulmonary sarcomatoid carcinoma

Pulmonary sarcomatoid carcinoma (PSC) contains carcinomatous component (CaC) and sarcomatous component (SaC). Herein, we explored the genomic origin and intratumor heterogeneity (ITH) of PSC. We collected 31 resected PSC tumors and obtained CaC and SaC by laser capture microdissection for next-generation sequencing. The majority of PSCs (97%) had component-shared alterations. Driver mutations in EGFR, KRAS, MET, PIK3CA, and EML4-ALK fusion were mostly component-shared. Twenty-seven (87%) PSCs had component-private alterations. Compared with pure lung adenocarcinoma (LUAD), adenocarcinoma component of PSC showed lower EGFR incidence. Compared with other typical sarcomas, numerous genes of SaC exhibited significant differences. CaC and SaC had equivalent and proportional tumor mutation burden (TMB), as well as PD-L1 level. Compared with LUAD, SaC had significant higher TMB and more patients with high PD-L1 expression (tumor proportion score ≥50%). PSC with lower proportion of component-shared alterations (trunk-ratio) had a prolonged disease-free survival (DFS), regardless of the influence of clinical factors. We conclude that most PSCs originate from a monoclone accompanied by genomic ITH which is a potential independent prognostic factor, and more proportion of PSCs may be beneficial from immune checkpoint inhibitors.

Genetic heterogeneity and predictive biomarker for pulmonary sarcomatoid carcinomas

PURPOSE

The aim of this study is to investigate the genetic heterogeneity (carcinomatous vs. sarcomatous components) and predictive biomarkers in patients with pulmonary sarcomatoid carcinoma (PSC).

METHODS

Genetic alterations and biomarkers of immunotherapy were performed in a discovery set (n = 6) of PSC. Next-generation sequencing (NGS) on a pan-cancer gene panel was applied to detect the genetic alterations in each component, and the respective mutation profiling and tumor mutation burden (TMB) were compared as well. Immunohistochemistry (IHC) assay with SP263 antibody was used to detect the protein expression of programmed death-ligand 1 (PD-L1) in each component.

RESULTS

Comparative genetic analysis revealed that the separate carcinomatous and sarcomatous components shared strikingly common mutations. TP53 (4/6, 66.7%) was the most common genetic alteration in 6 PSC patients. MET exon 14 skipping was detected in one case, accounting for 16.7%. An EZR-ROS1 fusion (EZR: intron10-ROS1: intron32) was identified in one case. The TMB of the two components was similar. Nevertheless, significantly higher PD-L1 expression was found in carcinomatous components compared to sarcomatous components. MDM2 amplification was detected in 2/6 (33.3%) of cases and STK11 mutation in 1/6 (16.7%) of cases.

CONCLUSIONS

PSC containing carcinomatous and sarcomatous components had a mild heterogeneity; the two components may evolve from common ancestral cells. High PD-L1 expression suggests that immunotherapy could be used as a potential therapy for PSC patients, while patients with negative immune-responsive genes need to be screened out. Altogether, these findings further highlight that the detection of genetic alteration and PD-L1 expression plays an important role in treatment of patients with PSC.

Analysis of targeted somatic mutations in pleomorphic carcinoma of the lung using next-generation sequencing technique

BACKGROUND

Pleomorphic carcinoma (PC) of the lung is a rare type of lung cancer with aggressive characteristics and a poor prognosis. Because it is rare, the molecular characteristics of PC remain unclear.

METHODS

A gene mutation analysis was performed using next-generation sequencing (NGS) in patients with PC of the lung who had undergone surgical resection.

RESULTS

A total of nine patients were enrolled in the study. All the patients were male and eight had a history of smoking. Eight tumors contained spindle cells and three contained giant cells. Mutations considered significant were found in eight of the nine patients: in TP53 in five patients, in MET in two patients, and in ALK, ERBB2, PIK3CA, APC, NF1, and CDKN2A in one patient each. No EGFR mutation was detected in our analysis. Co-mutations were detected in three patients: TP53 with MET and NF1, TP53 with ERBB2, and PIK3CA with CDKN2A.

CONCLUSIONS

TP53 mutations were detected most frequently in PC of the lung with NGS analysis. Different co-mutations were seen in several specimens.

KEY POINTS

Significant findings of the study This study demonstrates that mutations in the TP53 gene are frequently found and co-mutations are sometimes found in pleomorphic carcinoma of the lung using genomic profiling analysis. What this study adds Our results will help to analogize the genetic characteristics and potential target of molecular-targeted agents of pleomorphic carcinoma of the lung.

Unproductive Effects of ALK Gene Amplification and Copy Number Gain in Non-Small-Cell Lung Cancer. ALK Gene Amplification and Copy Gain in NSCLC

Background: The Anaplastic Lymphoma Kinase (ALK) gene is known to be affected by several genetic alterations, such as rearrangement, amplification and point mutation. The main goal of this study was to comprehensively analyze ALK amplification (ALK-A) and ALK gene copy number gain (ALK-CNG) in a large cohort of non-small-cell lung cancer (NSCLC) patients in order to evaluate the effects on mRNA and protein expression. Methods: ALK locus number status was evaluated in 578 NSCLC cases by fluorescence in situ hybridization (FISH). In addition, ALK immunohistochemistry and ALK mRNA in situ hybridization were performed. Results: Out of 578 cases, 17 cases showed ALK-A. In addition, 14 cases presented ALK-CNG and 72 cases presented chromosome 2 polyploidy. None of those carrying ALK-A and -CNG showed either ALK immunohistochemical expression or ALK mRNA expression through in situ hybridization. We observed a high frequency of extra copies of the ALK gene. Conclusions: Our findings demonstrated that ALK-A is not involved in mRNA production and consequently is not involved in protein production; these findings support the hypothesis that ALK-A might not play a role in the pathogenesis of NSCLC, underlining the absence of a specific clinical application.

Pulmonary sarcomatoid carcinoma presenting both ALK rearrangement and PD-L1 high positivity: A case report on the therapeutic regimen

RATIONALE

Pulmonary sarcomatoid carcinoma (PSC) represents <1% of all lung cancers and is characterized by a very poor prognosis. The optimal therapeutic regimen remains unclear. We describe a rare case of PSC with both anaplastic lymphoma kinase (ALK)-arranged and high levels of programmed death ligand 1 (PD-L1) expression.

PATIENT CONCERNS

A 46-year-old woman, nonsmoker, came to our attention due to uncontrolled pain in the lower left limb.

DIAGNOSIS

PSC with both ALK rearrangement and high levels of PD-L1 expression.

INTERVENTIONS

The patient started first-line systemic treatment with pembrolizumab reporting stable disease; at progression, she received second-line treatment with crizotinib. The treatment was not well-tolerated, and the patient then underwent 5 cycles of ceritinib treatment.

OUTCOMES

The patient showed a partial response to targeted therapy. At progression, brigatinib was initiated, but the patients reported liver progression soon after the initiation of this therapy.

LESSONS

Molecular-driven investigation is necessary in PSC for treatment selection.

Uncommon Types of Lung Carcinoma With Mixed Histology: Sarcomatoid Carcinoma, Adenosquamous Carcinoma, and Mucoepidermoid Carcinoma

CONTEXT

- Lung tumors are histologically heterogeneous, but classification of lung carcinoma has prognostic impact and increasingly, specific molecular correlates.

OBJECTIVE

- To update the gross, microscopic, and molecular pathology of unusual lung carcinomas to assure accurate classification. In entities with mixed histology, the recognition of specific features or rare patterns is critical to diagnosis. These diagnoses can identify tumors with aggressive clinical behavior, and diagnostic pitfalls can therefore result in underdiagnosis of these already rare entities. Incorrect classification of more indolent tumors into the more aggressive categories can also occur. In the area of molecular pathology, these unusual tumors have a specific spectrum of molecular alterations.

DATA SOURCES

- PubMed searches for lung and sarcomatoid carcinoma, pleomorphic carcinoma, blastoma, carcinosarcoma, and adenosquamous and mucoepidermoid carcinoma were undertaken and this information was integrated with clinical experience of the author.

CONCLUSIONS

- These uncommon carcinomas have specific clinicopathologic features, and attention to their gross and microscopic pathology leads to classification with important associated molecular findings.

Efficacy of immunotherapy in sarcomatoid lung cancer, a case report and literature review

Sarcomatoid carcinoma is a subtype of non-small cell lung cancer (NSCLC) characterized by mesenchymal – epithelial transition component and awful prognosis. In this report, based on a case of stage IV lung sarcomatoid carcinoma with an extraordinary evolution and survival over 4 years, we address unresolved questions about the treatment of this cancer. We also make a literature review about the key factors that characterize this histology and that should be considered when treating those patients. Sarcomatoid carcinoma presents with mutations as KRAS, EGFR, ALK or MET in up to 70% of cases, and an important expression of PD-L1 (also called B7-H1), which can influence treatment of those patients with new drugs as immune checkpoint inhibitors. Immunotherapy has changed the horizon of patients with stage IV lung cancers without driver mutations, as their survival has improved extraordinary. Moreover, radical treatments are being considered in long survivors with oligometastatic disease. In this report, we review targeted and radical therapy, treatment duration and the mechanisms responsible of disease evolution of sarcomatoid tumors.

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Sarcomatoid lung cancer is a rare entity with awful prognosis.

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It may express driver mutations for potential treatment of those patients.

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There are arising data of efficacy of immunotherapy in sarcomatoid lung carcinoma.

Pulmonary sarcomatoid carcinoma: an analysis of a rare cancer from the Surveillance, Epidemiology, and End Results database

OBJECTIVES

Pulmonary sarcomatoid carcinoma (PSC) is a rare malignant neoplasm that accounts for a small percentage of non-small-cell lung carcinoma (NSCLC). At least 10% of PSCs has a spindle and/or giant cell component, which is often associated with a poor prognosis. We reviewed the Surveillance, Epidemiology, and End Results (SEER) database for the clinicopathological characteristics and surgical outcomes of PSCs.

METHODS

The SEER database (1973-2013) was queried for PSC. A comparison between PSC and other NSCLC patients was performed. Cox regression for overall survival (OS) and logistic regression for node-positive predictors were performed. A propensity-matched (1:2) analysis (including age, gender, grade and stage) among surgically treated cases was done to compare OS in PSC versus other NSCLCs.

RESULTS

A total of 955 899 NSCLC patients were identified; of these, 4987 patients had been diagnosed with PSC (0.52%). Men represented 60.9% of cases, with a median age of 68 years. The median size of the tumour was 5 cm and 3.5 cm in PSCs and NSCLCs, respectively (P < 0.001). PSC patients had significantly less Stage I, more high-grade tumours, advanced T stage, N+ disease and M1 disease (P < 0.001). In the PSC cohort, the most significant predictor of N+ disease on multivariate analysis was advanced T stage (P < 0.001). Predictors of OS in Stages I/II PSC on multivariate analysis were advanced age [P < 0.001, hazard ratio (HR) = 1.03], male gender (P = 0.024, HR = 1.25), carcinosarcoma (P = 0.002, HR = 1.76), grade (P = 0.033, HR = 1.81), T stage (P = 0.003, HR = 1.75), N status (P = 0.001, HR = 1.90) and surgical resection (P < 0.001, HR = 0.58). Among matched surgically resected cohorts, a poorer prognosis for OS was evident in PSCs in early stages (I/II) than in other NSCLCs (P = 0.009).

CONCLUSIONS

PSC patients present with more advanced stage and with worse survival outcomes than other NSCLC patients. While surgical resection conveys a survival advantage in PSC, this group represents a population at a high risk for relapse and should be evaluated for novel adjuvant therapies.

Epidemiological features of lung giant cell carcinoma and therapy for patients with EGFR mutations based on case reports and the surveillance, epidemiology, and end results (SEER) database

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are the standard first line treatment for advanced non-small cell lung cancer (NSCLC) with sensitive EGFR mutations. Among NSCLC, giant cell carcinoma of the lung (GCCL) is a rare pathological subtype with poor prognosis, with no confirmed evidence about its epidemiological features or therapeutic efficiency of EGFR-TKIs. We present two advanced GCCLs with sensitive EGFR mutations, also collected the cases of GCCL from our hospital and the Surveillance, Epidemiology, and End Results (SEER) program. Kaplan-Meier methods and Cox proportional hazards modeling were used to perform the survival analyses. Both two cases of advanced GCCL with sensitive EGFR mutations benefited from EGFR-TKIs. Twelve GCCLs were recorded in our hospital from May 2006 to July 2015. GCCL is associated with males (83.3%) and smoking status (63.6%). The EGFR mutation rate was 40.0%. In SEER database, the total number of GCCLs was 184, 0.11% for all NSCLCs. In Kaplan-Meier analysis, the 5-year overall survival of GCCL patients was significantly lower than that of non-GCC NSCLC (16% and 19%; P<0.001), and it was confirmed in multivariate analysis. Further survival analyses indicated that male were more susceptible to GCCL and GCCL was prone to metastasize. Only age and M stage were independent prognostic factors for GCCL in the multivariate analysis. In conclusion, GCCL was an unfavorable prognostic factor and associated with males and metastasis. GCCL patients with sensitive EGFR mutations may also benefit from EGFR-TKI, we therefore recommend the evaluation of EGFR in the treatment of advanced GCCL.

Sarcomatoid Carcinoma of the Lung: The Mayo Clinic Experience in 127 Patients

BACKGROUND

Pulmonary sarcomatoid carcinoma (PSC) is an unusual form of non-small-cell lung cancer (NSCLC). Because of its rarity and heterogeneity, the treatment and prognosis of PSC have not been clearly described.

METHODS AND MATERIALS

We retrospectively evaluated all patients with a diagnosis of PSC from 1997 to 2015 at the Mayo Clinic (Rochester, MN). The clinical characteristics, treatment details, and outcomes were collected. The survival rates of the PSC patients were compared with those for other subtypes of NSCLC. We used propensity score matching to minimize the bias resulting from to imbalanced comparison groups.

RESULTS

The study included 127 PSC patients. The median age at diagnosis was 68 years (range, 32-89 years), most of whom were men (61%) and smokers (82%). The clinical stage was I, II, III, and IV in 15.9%, 20.6%, 22.2%, and 41.3%, respectively. The median survival time was 9.9 months (95% confidence interval [CI], 7.6-12.6 months). The 1-, 2-, and 5-year survival rates were 42%, 23%, and 15%, respectively. Most patients received multimodality treatment. Of the 3 patients who received neoadjuvant chemotherapy, a partial response was demonstrated in 2. Twenty-five patients who underwent palliative chemotherapy were evaluated for tumor response: 52% experienced progression, 40% stable disease, 8.0% a partial response, and 0% a complete response. Multivariate analysis showed T stage, M stage, and treatment with surgery plus neoadjuvant chemotherapy or surgery plus adjuvant therapy were independent prognostic factors (P < .05). In matched analysis, multivariate models revealed worse overall survival for PSC compared with adenocarcinoma (hazard ratio, 2.38; 95% CI, 1.61-2.53) and squamous cell carcinoma (hazard ratio, 2.20; 95% CI, 1.44-2.34).

CONCLUSION

We found the outcome of PSC to be significantly worse than that of adenocarcinoma and squamous cell carcinoma. Neoadjuvant or adjuvant chemotherapy, in addition to surgical resection, should be considered.

Inter-relationship between PD-L1 expression and clinic-pathological features and driver gene mutations in pulmonary sarcomatoid carcinomas

INTRODUCTION

Pulmonary Sarcomatoid Carcinoma (PSC) is a rare subset of NSCLC, associated with worse prognosis and resistant to platinum-based regimens. Recent investigations have shown high levels of PD-L1 expression in PSC, providing a rationale for the potential use of immunotherapy. In this study, we investigated whether the PD-L1 expression was related to clinico-pathologic and molecular characteristics.

MATERIALS AND METHODS

Fortythree surgically-resected PSCs were selected from 2006 to 2014 and clinical information retrieved. PD-L1 expression was analyzed by immunohistochemistry and correlated with the clinic-pathologic features and driver gene mutations analyzed by Next-Generation-Sequencing. Correlation of clinical, pathological and genetic variants with PD-L1 expression positivity were tested by Fisher's exact test analysis.

RESULTS

About 25% of PSCs showed a significant expression of PD-L1 (positive staining defined as staining in ≥10% of tumor cells). PD-L1 expression was associated with aggressive pathological features of PSCs including N2-involvement (PD-L1 positive in 83.3% of N2-PSCs vs in 16.2% of N0/N1-PSCs, p=0.003) and presence of either local (p=0.038) and distant metastases (p=0.022). Furthermore, PD-L1 expression was significantly associated with the overall mutational load of the tumors (PD-L1 positivity only in PSCs with at least one mutational event) and in particular with the presence of KRAS mutation (PD-L1 positive in 44.4% of KRAS-Mut PSCs vs 12.0% in KRAS-Wild PSCs). The correlation between PD-L1 expression and KRAS-mutation were found at univariate analysis (p=0.031), even considering PD-L1 as a continuous variable (p=0.018), and confirmed at multivariate analysis (p=0.035). The mutational status of the other genes explored in the NGS-panel (EGFR, APC, PTEN, PIK3CA, TP53 and STK11) did not correlate with PD-L1 expression.

CONCLUSIONS

PD-L1 expression significantly correlates with overall mutational load and KRAS mutational status in pulmonary sarcomatoid carcinomas.

Treatment of Lung Carcinosarcoma and Other Rare Histologic Subtypes of Non-small Cell Lung Cancer

OPINION STATEMENT

Lung carcinosarcoma (PCS) and other histological subtypes of non-small cell lung cancer, such as primary pulmonary lymphoma (PPL), pulmonary carcinoid (PC), and primary pulmonary lymphoepithelioma-like carcinoma (LELC), are rare. For their low incidence, the diagnosis and treatment are still controversial. Some patients only need surgery, while others may need chemotherapy, radiotherapy, or targeted therapy. In this paper, we retrospectively reviewed the literature of some rare histological subtype of NSCLC for the recent 20 years, and try to get some conclusions.

Characteristics and Prognostic Analysis of 69 Patients With Pulmonary Sarcomatoid Carcinoma

BACKGROUND

Pulmonary sarcomatoid carcinoma (PSC) is a rare malignancy.

METHODS

A total of 69 patients with PSC treated at a single institution in southern China with long-term follow-up were evaluated in this study. We analyzed the clinical characteristics, immunohistochemical profiles, epidermal growth factor receptor mutation status, K-RAS mutation status, treatments, and prognosis.

RESULTS

PSC mainly occurred in young male patients with a history of smoking. Most patients received multimodality treatments and the majority had early-stage disease. The median survival time was 19.1 months, and the 5-year survival rate was 17.4%. The patients without distant metastasis, with normal or higher body mass index (≥18.5), with normal hemoglobin, with smaller tumor size (≤4 cm), and those who received complete resection had significantly better overall survival (P<0.05). The patients with pleomorphic carcinoma had much worse prognosis. In a Cox regression model, M stage, pathology, and having received a complete resection were independent prognostic factors (P<0.05).

CONCLUSIONS

PSC is a unique lung malignancy with poor prognosis. Patients receiving complete resection had better prognosis, likely a reflection of early-stage disease. Neither neoadjuvant nor adjuvant chemotherapy improved patient survival for those with early-stage disease. The retrospective design and small sample size limited the generalizability. Future multicenter collaborations may be necessary to determine the optimal treatment.

Clinical Significance and Next-Generation Sequencing of Chinese Pulmonary Sarcomatoid Carcinoma

Pulmonary Sarcomatoid Carcinoma (PSC) constitutes a heterogeneous group of non-small-cell lung carcinomas (NSCLCs) with a poor prognosis. In this study, a group of 7 patients with PSC was studied. Microscope analysis of all 7 cases revealed a pleomorphic carcinoma subtype. Moreover, 5 cases (71.4%) were composed entirely of malignant sarcomatoid-like elements, and 2 cases (28.6%) were composed of malignant sarcomatoid-like elements and at least 10% adenocarcinoma-like elements. Immunohistochemically, the PSC components of all 7 cases were positive for vimentin and cytokeratins, including cytokeratin (CK) and cytokeratin 7 (CK7). Next-Generation Sequencing (NGS) was performed, and a total of 136 putative somatic variants and one gene fusion were identified, of which 16 variants were considered hot spot mutations, including the genes EGFR, EML4-ALK, MET, BRAF, PIK3CA, and TP53. Of these hot spot mutations, one sample expressing an EML4-ALK fusion was further confirmed by Ventana IHC, and one sample containing an EGFR exon 19 deletion was also confirmed. The NGS results imply that TP53 mutations occur often in PSCs and that EML4-ALK fusion events and EGFR exon deletions also occur in these rare tumors. Molecular targeted therapy may be a useful treatment strategy for these rare lung tumors.

Thymus neuroendocrine tumors with CTNNB1 gene mutations, disarrayed ß-catenin expression, and dual intra-tumor Ki-67 labeling index compartmentalization challenge the concept of secondary high-grade neuroendocrine tumor: a paradigm shift

We herein report an uncommon association of intimately admixed atypical carcinoid (AC) and large cell neuroendocrine (NE) carcinoma (LCNEC) of the thymus, occurring in two 20- and 39-year-old Caucasian males. Both tumors were treated by maximal thymectomy. The younger patient presented with a synchronous lesion and died of disease after 9 months, while the other patient was associated with a recurrent ectopic adrenocorticotropic hormone Cushing's syndrome and is alive with disease at the 2-year follow-up. MEN1 syndrome was excluded in either case. Immunohistochemically, disarrayed cytoplasmic and nuclear ß-catenin expression was seen alongside an intra-tumor Ki-67 antigen labeling index (LI) ranging from 2 to 80% in the younger patient's tumor and from 3 to 45% in the other. Both exhibited upregulated cyclin D1 and retinoblastoma, while vimentin was overexpressed in the recurrent LCNEC only. Next-generation sequencing revealed CTNNB1, TP53, and JAK3 mutations in the synchronous tumor and CTNNB1 mutation alone in the metachronous tumor (the latter with the same mutation as the first tumor of 17 years prior). None of the 23 T-NET controls exhibited this hallmarking triple alteration (p = 0.003). These findings suggested that LCNEC components developed from pre-existing CTNNB1-mutated AC upon loss-of-function TP53 and gain-of-function JAK3 mutations in one case and an epithelial-mesenchymal transition upon vimentin overexpression in the other case. Both tumors maintained intact cyclin D1-retinoblastoma machinery. Our report challenges the concept of secondary LCNEC as an entity that develops from pre-existing AC as a result of tumor progression, suggesting a paradigm shift to the current pathogenesis of NET.

Pathologic Findings and Long-Term Results After Surgical Treatment for Pulmonary Sarcomatoid Tumors: A Multicenter Analysis

BACKGROUND

Pulmonary sarcomatoid carcinoma (PSC) is a very rare subtype of non-small cell lung cancer (NSCLC). The aim of this study was to clarify the pathologic characteristics and long-term survival after surgical treatment in patients with PSC.

METHODS

From January 2003 to December 2013, we retrospectively reviewed the clinical findings, surgical notes, and pathologic and follow-up data from 148 consecutive patients who underwent curative resection for PSC in 5 institutions. The Kaplan-Meier method, log-rank test, and Cox regression analysis were used.

RESULTS

Mean age and male to female ratio were 66.6 ± 9.9 years and 120:28, respectively. Surgical resection (pneumonectomy in 8 patients, bilobectomy in 132 patients, and sublobar resection in 8 patients) was complete in 142 cases (96%). At pathologic evaluation, 36 patients (24%) had stage I, 69 patients (47%) had stage II, 33 patients (22%) had stage III, and 10 patients (7%) had stage IV disease. A "biphasic tumor" (PSC with an NSCLC component) was observed in 77 patients (52%). We detected a high rate of vascular emboli in the surgical specimens (overall, 68%; 57% in pathologic stage I tumors), whereas lymphatic emboli were found in 30% of cases (5% of pathologic stage I tumors). Overall median and 5-year long-term survival (LTS) was 19 months and 12.6% (LTS, 16.3% in pathologic stage I), respectively. Distant recurrences frequently occurred after surgical treatment (81%), even in pathologic stage I tumors that underwent R0 resection (62%). Multivariable survival analysis identified R+ resection (hazard ratio [HR],12.3; 95% confidence interval [CI], 3.67-41.28; p < 0.0001), advanced pathologic stage (HR, 5.75; 95% CI, 2.55-12.98; p < 0.0001), and the presence of vascular emboli (HR, 1.67; 95% CI, 1.05-2.67; p = 0.0327) as independent negative prognostic factors.

CONCLUSIONS

PSCs have very aggressive behavior and high metastatic potential even in early stages. R+ resection, pathologic TNM status, and the presence of vascular emboli are independent prognostic factors.

Pulmonary adenocarcinoma with mucin production modulates phenotype according to common genetic traits: a reappraisal of mucinous adenocarcinoma and colloid adenocarcinoma

Whether invasive mucinous adenocarcinoma (IMA) and colloid adenocarcinoma (ICA) of the lung represent separate tumour entities, or simply lie within a spectrum of phenotypic variability, is worth investigating. Fifteen ICA, 12 IMA, 9 ALK‐rearranged adenocarcinomas (ALKA), 8 non‐mucinous KRAS‐mutated adenocarcinomas (KRASA) and 9 mucinous breast adenocarcinomas (MBA) were assessed by immunohistochemistry for alveolar (TTF1, cytoplasmic MUC1), intestinal (CDX‐2, MUC2), gastric (membrane MUC1, MUC6), bronchial (MUC5AC), mesenchymal (vimentin), neuroendocrine (chromogranin A, synaptophysin), sex steroid hormone‐related (oestrogen and progesterone receptors), pan‐mucinous (HNF4A) and pan‐epithelial (keratin 7) lineage biomarkers and by targeted next generation sequencing (TNGS) for 50 recurrently altered cancer genes. Unsupervised clustering analysis using molecular features identified cluster 1 (IMA and ICA), cluster 2 (ALKA and KRASA) and cluster 3 (MBA) (p < 0.0001). Cluster 1 showed four histology‐independent sub‐clusters (S1 to S4) pooled by HFN4A and MUC5AC but diversely reacting for TTF1, MUC1, MUC2, MUC6 and CDX2. Sub‐cluster S1 predominantly featured intestinal‐alveolar, S2 gastrointestinal, S3 gastric and S4 alveolar differentiation. In turn, KRASA and ALKA shared alveolar lineage alongside residual MUC5AC expression, with additional focal CDX2 and diffuse vimentin, respectively. A proximal‐to‐distal scheme extending from terminal (TB) and respiratory (RB) bronchioles to alveolar cells was devised, where S3 originated from distal TB (cellular mucinous adenocarcinoma), S2 from proximal RB (secreting mucinous adenocarcinoma), S1 from intermediate RB (mucin lake‐forming colloid adenocarcinoma), S4 from distal RB (colloid alveolar adenocarcinoma), KRASA from juxta‐alveolar RB (KRAS‐mutated non‐mucinous adenocarcinoma) and ALKA from juxta‐bronchial alveolar cells (ALK‐translocated adenocarcinoma). TNGS analysis showed KRAS, LKB1, TP53, APC and CDKN2A mutation predominance. In conclusion, IMA and ICA are basket categories, which likely originate from distinct domains of stem/progenitor cells spatially distributed along bronchioles upon common molecular features and genetic alterations.

Pulmonary Sarcomatoid Carcinoma with ALK Rearrangement: Frequency, Clinical-Pathologic Characteristics, and Response to ALK Inhibitor

PURPOSE: The incidence of anaplastic lymphoma kinase (ALK) rearrangement in pulmonary sarcomatoid carcinoma (PSC) is controversial. In this study, we aimed to reveal the reliable frequency and the clinical-pathologic characteristics of pulmonary sarcomatoid carcinoma (PSC) with ALK rearrangement in Chinese population, and to provide insight into the translatability of anti-ALK treatment in this treatment-refractory disease. METHODS: Immunohistochemistry (IHC) using a Ventana anti-ALK (D5F3) rabbit monoclonal antibody was performed in 141 PSC specimens collected from multiple medical centers. IHC-positive cases were then confirmed using ALK fluorescent in situ hybridization (FISH). The incidence rates and clinical-pathologic characteristics of ALK-rearranged PSC were then analyzed. Response to ALK inhibitor crizotinib in a patient with ALK-rearranged PSC was evaluated according to the response evaluation criteria for solid tumors (RECIST) version 1.1. RESULTS: Five of 141 (3.5%) of PSCs showed ALK rearrangement-positive by IHC and then were confirmed by FISH. Two were carcinosarcomas and the other three were pulmonary pleomorphic carcinoma (PPC). Strong positive ALK rearrangement was observed in both the epithelioid and sarcomatoid components. The median age of ALK-positive patients was younger than that of ALK-negative patients. PSCs in never-smokers were more likely to harbor ALK rearrangement than those in former or current smokers (P < .05). A 40-year-old woman diagnosed with ALK-rearranged PPC experienced a partial response (−32%) to the ALK inhibitor crizotinib. CONCLUSIONS: The incidence rates of ALK rearrangement in PSC in the Chinese population are similar to those of other subtypes of NSCLC. PSCs in younger never-smokers are more often to harbor ALK rearrangement. ALK inhibitors may serve as an effective treatment for ALK-rearranged PSC.

ALK gene copy number in lung cancer: Unspecific polyploidy versus specific amplification visible as double minutes

BACKGROUND

Gains of a gene due to DNA polyploidy versus amplification of the specific locus are distinct molecular alterations in tumors.

OBJECTIVE

We quantified copy number gains of ALK gene due to unspecific polyploidy versus amplifications of the specific locus in a series of non-small cell lung cancers.

METHODS

The locus specific ALK copy (LSI) number status was evaluated in 205 cases by FISH. Ratio LSI ALK copy number corrected for control probes CEP2, CEP3 and CEP17 (CEPs) was scored. Amplification of the specific ALK locus was defined when ratio set to ≥ 2 while polyploidy was interpreted when the increase in gene copy resulted < 2 in ratio (LSI/control CEPs).

RESULTS

Twenty one cases (10.2%) showed ≥ 8 ALK signals, 68 cases (33.2%) 3-7 signals and 116 cases (56.6%) a mean of 2 signals. Only 2/21 cases of the cohort harboring ≥ 8 signals showed a ratio ≥ 2 after CEPs correction interpretable as amplified, showing numerous doubled fluorescent spots. All the remaining cases showed a mirrored number of fluorescent spots per each CEPs, interpretable as polyploidy.

CONCLUSION

We detected a high prevalence of ALK gene copy number usually due to polyploidy rather than ALK locus amplification, the latter visible prevalently as double minutes.

The impact of immunohistochemistry on the classification of lung tumors

INTRODUCTION

To highlight the role of immunohistochemistry to lung cancer classification on the basis of existing guidelines and future perspectives.

AREAS COVERED

Four orienting key-issues were structured according to an extensive review on the English literature: a) cancer subtyping; b) best biomarkers and rules to follow; c) negative and positive profiling; d) suggestions towards an evidence-based proposal for lung cancer subtyping. A sparing material approach based on a limited number of specific markers is highly desirable. It includes p40 for squamous cell carcinoma ('no p40, no squamous'), TTF1 for adenocarcinoma, synaptophysin for neuroendocrine tumors and vimentin for sarcomatoid carcinoma. A close relationship between genotype and phenotype also supports a diagnostic role for negative profiles. Expert commentary: Highly specific and sensitive IHC markers according to positive and negative diagnostic algorithms seem appropriate for individual patients' lung cancer subtyping.

Pretreatment of donor islets with papain improves allograft survival without systemic immunosuppression in mice

Although current immunosuppression protocols improve the efficacy of clinical allogenic islet transplantation, T cell-mediated allorejection remains unresolved, and major histocompatibility complexes (MHCs) play a crucial role in this process. Papain, a cysteine protease, has the unique ability to cleave the extracellular domain of the MHC class I structure. We hypothesized that pretreatment of donor islets with papain would diminish the expression of MHC class I on islets, reducing allograft immunogenicity and contributing to prolongation of islet allograft survival. BALB/c islets pretreated with papain were transplanted into C57BL/6J mice as an acute allorejection model. Treatment with 1 mg/mL papain significantly prolonged islet allograft survival. In vitro, to determine the inhibitory effect on T cell-mediated alloreactions, we performed lymphocyte proliferation assays and mixed lymphocyte reactions. Host T cell activation against allogenic islet cells was remarkably suppressed by pretreatment of donor islet cells with 10 mg/mL papain. Flow cytometric analysis was also performed to investigate the effect of papain treatment on the expression of MHC class I on islets. One or 10 mg/mL papain treatment reduced MHC class I expression on the islet cell surface. Pretreatment of donor islets with papain suppresses MHC class I-mediated allograft rejection in mice and contributes to prolongation of islet allograft survival without administration of systemic immunosuppressants. These results suggest that pretreatment of human donor islets with papain may reduce the immunogenicity of the donor islets and minimize the dosage of systemic immunosuppressants required in a clinical setting.

ALK gene copy number gains in non-small-cell lung cancer: prognostic impact and clinico-pathological correlations

Background

The correlation between ALK gene copy number gain (ALK-CNG) and prognosis in the context of advanced non-small-cell lung cancer (NSCLC) remains a controversial issue. This study aimed to evaluate the association among ALK-CNG according to Fluorescent In Situ Hybridization (FISH), clinical characteristics and survival in resectable and advanced NSCLC.

Methods

Clinical and pathological data of patients with resectable and advanced NSCLC were retrospectively collected. Tumor tissues were analyzed for ALK-CNG by FISH, and patients were divided in 3 groups/patterns on the basis of ALK signals: disomic [Pattern A], 3–7 signals [Pattern B], >7 signals [Pattern C]. The association between clinical and pathological features and ALK-CNG patterns was evaluated. Disease/progression-free and overall survival (DFS/PFS and OS) were estimated using the Kaplan-Meyer method.

Results

A number of 128 (76.6 %) out of the 167 eligible patients were evaluable for ALK-CNG, displaying pattern A, B and C in 71 (42.5 %), 42 (25.1 %) and 15 (9 %) patients, respectively. Gains in ALK-CNG appear to be more frequent in smokers/former smokers than in non-smokers (74.2 % versus 20.4 %, respectively, p = 0.03). Pattern A and C seem more frequently associated with higher T-stage (T3-4), while pattern B appears more represented in lower T-stage (T 1-2) (p = 0.06). No significant differences in survival rate were observed among the above groups.

Conclusions

A high ALK-CNG pattern might be associated with smoking status and theoretically it might mirror genomic instability. The implications for prognosis should be prospectively investigated and validated in larger patients’ series.

Trial registration

We confirm that all the study was performed in accordance with relevant guidelines and regulations and that all the protocol (part of a larger project MFAG 2013 N.14282) was approved by the local Ethics Committee of the Azienda Ospedaliera Universitaria Integrata of Verona on November 11st, 2014.

The 2015 World Health Organization Classification of Lung Tumors: Impact of Genetic, Clinical and Radiologic Advances Since the 2004 Classification

The 2015 World Health Organization (WHO) Classification of Tumors of the Lung, Pleura, Thymus and Heart has just been published with numerous important changes from the 2004 WHO classification. The most significant changes in this edition involve (1) use of immunohistochemistry throughout the classification, (2) a new emphasis on genetic studies, in particular, integration of molecular testing to help personalize treatment strategies for advanced lung cancer patients, (3) a new classification for small biopsies and cytology similar to that proposed in the 2011 Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification, (4) a completely different approach to lung adenocarcinoma as proposed by the 2011 Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification, (5) restricting the diagnosis of large cell carcinoma only to resected tumors that lack any clear morphologic or immunohistochemical differentiation with reclassification of the remaining former large cell carcinoma subtypes into different categories, (6) reclassifying squamous cell carcinomas into keratinizing, nonkeratinizing, and basaloid subtypes with the nonkeratinizing tumors requiring immunohistochemistry proof of squamous differentiation, (7) grouping of neuroendocrine tumors together in one category, (8) adding NUT carcinoma, (9) changing the term sclerosing hemangioma to sclerosing pneumocytoma, (10) changing the name hamartoma to "pulmonary hamartoma," (11) creating a group of PEComatous tumors that include (a) lymphangioleiomyomatosis, (b) PEComa, benign (with clear cell tumor as a variant) and

AKT1 and BRAF mutations in pediatric aggressive fibromatosis

Aside from the CTNNB1 and adenomatous polyposis coli (APC) mutations, the genetic profile of pediatric aggressive fibromatosis (AF) has remained poorly characterized. The aim of this study was to shed more light on the mutational spectrum of pediatric AF, comparing it with its adult counterpart, with a view to identifying biomarkers for use as prognostic factors or new potential therapeutic targets. CTNNB1,APC,AKT1,BRAF TP53, and RET Sanger sequencing and next‐generation sequencing (NGS) with the 50‐gene Ion AmpliSeq Cancer Hotspot Panel v2 were performed on formalin‐fixed samples from 28 pediatric and 33 adult AFs. The prognostic value of CTNNB1,AKT1, and BRAF mutations in pediatric AF patients was investigated. Recurrence‐free survival (RFS) curves were estimated with the Kaplan–Meier method and statistical comparisons were drawn using the log‐rank test. In addition to the CTNNB1 mutation (64%), pediatric AF showed AKT1 (31%), BRAF (19%), and TP53 (9%) mutations, whereas only the CTNNB1 mutation was found in adult AF. The polymorphism Q472H VEGFR was identified in both pediatric (56%) and adult (40%) AF. Our results indicate that the mutational spectrum of pediatric AF is more complex than that of adult AF, with multiple gene mutations involving not only CTNNB1 but also AKT1 and BRAF. This intriguing finding may have clinical implications and warrants further investigations.

A new look at the ALK gene in cancer: copy number gain and amplification

To date, ALK-rearrangement is a molecular target in several cancers, i.e. NSCLC. The dramatic benefits of crizotinib have prompted research into identifying other possible patients carrying ALK gene alterations with possible clinical significance. The ALK gene is involved not only in several rearrangements but also in other alterations such as amplification. ALK-amplification (ALK-A) is a common genetic event in several cancers, generally associated with poor outcome and more aggressive behaviour. Here we review the role of ALK-A in cancer as a prognostic and predictive biomarker. Furthermore, several critical issues regarding ALK-A in relation to; methods of detection, acquired resistance and ALK second generation inhibitors are analyzed. We conclude that ALK-A could be an intriguing alteration in the context of targeted therapy.

Next-Generation Sequencing of Pulmonary Sarcomatoid Carcinoma Reveals High Frequency of Actionable MET Gene Mutations

PURPOSE

To further understand the molecular pathogenesis of pulmonary sarcomatoid carcinoma (PSC) and develop new therapeutic strategies in this treatment-refractory disease.

MATERIALS AND METHODS

Whole-exome sequencing in a discovery set (n = 10) as well as targeted MET mutation screening in an independent validation set (n = 26) of PSC were performed. Reverse transcriptase polymerase chain reaction and Western blotting were performed to validate MET exon 14 skipping. Functional studies for validation of the oncogenic roles of MET exon 14 skipping were conducted in lung adenosquamous cell line H596 (MET exon 14 skipped and PIK3CA mutated) and gastric adenocarcinoma cell line Hs746T (MET exon 14 skipped). Response to MET inhibitor therapy with crizotinib in a patient with advanced PSC and MET exon 14 skipping was evaluated to assess clinical translatability.

RESULTS

In addition to confirming mutations in known cancer-associated genes (TP53, KRAS, PIK3CA, MET, NOTCH, STK11, and RB1), several novel mutations in additional genes, including RASA1, CDH4, CDH7, LAMB4, SCAF1, and LMTK2, were identified and validated. MET mutations leading to exon 14 skipping were identified in eight (22%) of 36 patient cases; one of these tumors also harbored a concurrent PIK3CA mutation. Short interfering RNA silencing of MET and MET inhibition with crizotinib showed marked effects on cell viability and decrease in downstream AKT and mitogen-activated protein kinase activation in Hs746T and H596 cells. Concurrent PIK3CA mutation required addition of a second agent for successful pathway suppression and cell viability effect. Dramatic response to crizotinib was noted in a patient with advanced chemotherapy-refractory PSC carrying a MET exon 14 skipping mutation.

CONCLUSION

Mutational events of MET leading to exon 14 skipping are frequent and potentially targetable events in PSC.

EGFR and KRAS mutations in pulmonary pleomorphic carcinoma and their correlation with clinicopathologic features

Aim of the study

Pulmonary pleomorphic carcinoma (PPC) of the lung is a subset of poorly differentiated non-small cell lung cancers (NSCLCs). Because of its rarity, information on epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene (KRAS) mutations is controversial and sparse. The aim was to investigate the two key oncogenes’ characteristics and their correlation with clinical variables.

Material and methods

We retrospectively screened 110 paraffin-embedded surgically resected specimens from patients with PPC. Of these, follow-up information was available for 48 patients. We then successfully analyzed 70 PPC samples and examined EGFR and KRAS mutation status by direct sequencing. The findings were correlated with a control group of patients with other NSCLCs.

Results

In our department, PPC comprised about 1.57% of surgical resected cases (110/6990). 37.4% of patients smoked. EGFR mutations were detected in 11 cases (15.7%), with a significantly higher frequency in women than men (p = 0.011). KRAS mutations were detected in 10 cases (14.3%) and were more often found at age 65 or older (p = 0.02). Of interest, in PPC, all KRAS mutations occurred in never smokers. Also, most never smokers have transversion mutations (G→T) in PPCs and other NSCLCs.

Conclusions

Our results demonstrated a similar EGFR and KRAS mutation rate in Chinese PPC patients. EGFR tyrosine kinase inhibitors may be a treatment option for PPCs with EGFR mutations. Of note, EGFR mutations in PPC were commonly identified in women; therefore women should be high-priority candidates for mutation screening.

Anaplastic lymphoma kinase gene copy number gain in inflammatory breast cancer (IBC): prevalence, clinicopathologic features and prognostic implication

BACKGROUND

Inflammatory breast cancer (IBC) is the most aggressive form of breast cancer, and its molecular pathogenesis still remains to be elucidated. This study aimed to evaluate the prevalence and implication of anaplastic lymphoma kinase (ALK) copy number change in IBC patients.

METHODS

We retrospectively collected formalin-fixed, paraffin-embedded tumor tissues and medical records of IBC patients from several institutes in Korea. ALK gene copy number change and rearrangement were assessed by fluorescence in situ hybridization (FISH) assay, and ALK expression status was evaluated by immunohistochemical (IHC) staining.

RESULTS

Thirty-six IBC patients including those with HER2 (+) breast cancer (16/36, 44.4%) and triple-negative breast cancer (13/36, 36.1%) were enrolled in this study. ALK copy number gain (CNG) was observed in 47.2% (17/36) of patients, including one patient who harbored ALK gene amplification. ALK CNG (+) patients showed significantly worse overall survival compared to ALK CNG (-) patients in univariate analysis (24.9 months vs. 38.1 months, p = 0.033). Recurrence free survival (RFS) after curative mastectomy was also significantly shorter in ALK CNG (+) patients than in ALK CNG (-) patients (n = 22, 12.7 months vs. 43.3 months, p = 0.016). Multivariate Cox regression analysis with adjustment for HER2 and ER statuses showed significantly poorer RFS for ALK CNG (+) patients (HR 5.63, 95% CI 1.11-28.44, p = 0.037).

CONCLUSION

This study shows a significant presence of ALK CNG in IBC patients, and ALK CNG was associated with significantly poorer RFS.

Anaplastic Lymphoma Kinase (ALK) Rearrangement-positive Lung Cancer with Transformation to Pleomorphic Carcinoma

A 55-year-old woman was diagnosed with a tyrosine kinase inhibitor of anaplastic lymphoma kinase (ALK) rearrangement-positive lung adenocarcinoma and treated with chemotherapy consisting of crizotinib, a tyrosine kinase inhibitor of ALK, as second-line chemotherapy. However, the size of the metastatic adrenal lesion increased, and the patient died due to multiple organ failure. An autopsy report revealed that the metastatic lesion of the adrenal tumor was ALK rearrangement-positive pleomorphic carcinoma. The epithelial-mesenchymal transition (EMT) marker vimentin was immunohistochemically positive in both the lung and adrenal lesions. The present case report suggests the possibility of transformation into pleomorphic carcinoma as a result of EMT in patients with ALK rearrangement-positive lung cancer.