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

Combination of epirubicin and cyclophosphamide for the treatment of advanced pulmonary sarcomatoid carcinoma: A case report and literature review

ABSTRACT

Pulmonary sarcomatoid carcinoma (PSC) is a rare and atypical subset of non-small-cell lung cancer (NSCLC) characterized by its aggressive nature, poor prognosis, and limited responsiveness to conventional therapeutic modalities. The effectiveness of chemotherapy in managing PSC remains controversial, with platinum-based regimens often yielding unsatisfactory outcomes in advanced PSC patients. Herein, we present a male patient with PSC who did not have a driver gene mutation or express the programmed death ligand 1. He received combination chemotherapy of epirubicin and cyclophosphamide for the first time, which resulted in progression-free survival for seven months and a noteworthy partial tumor response. These findings suggest that the combination of epirubicin and cyclophosphamide might prove promising as a therapeutic option for patients diagnosed with PSC. Nevertheless, the significance of this novel approach necessitates further validation through high-quality clinical trials.

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.

Rare transformation from lung adenocarcinoma to sarcomatoid carcinoma mediates resistance to inhibitors targeting different driver oncogenes

Background

Phenotypic transition is a common resistance mechanism of targeted therapy. While transformations from lung adenocarcinoma (LUAD) to small-cell lung cancer or squamous-cell carcinoma have been extensively studied, the conversion into sarcomatoid carcinoma (SC) is rarely reported.

Methods

Genetic and histological examinations were systematically performed on tumor re-biopsy samples obtained from patients with advanced EGFR-mutant LUAD who progressed on EGFR-tyrosine kinase inhibitors (TKIs). EGFR wild-type patients were also identified who underwent the rare transformation from adenocarcinoma to SC following the ineffectiveness of inhibitors that target distinct driver oncogenes. Furthermore, we also retrospectively collected 42 cases diagnosed with primary pulmonary SC as a comparison cohort to comprehensively characterize the biological events and clinical outcomes of transformed SC.

Results

The sarcomatoid transformation mediated drug resistance in 2.5 % and 4.8 % of patients after failure on the first/second, and third-generation EGFR-TKIs. Transformation of sarcomatoid carcinoma is characterized by a higher frequency of TP53, RB1, and MET genetic alterations compared to cases lacking histological transformation; the PI3K signaling pathway was also significantly activated. Fifteen individuals were identified with a rare transition from adenocarcinoma to SC, consisting of seven cases with EGFR-activating mutations and eight cases without EGFR mutations. All sarcomatoid-transformed samples not only retained their original driver mutations but also shared specific genetic alterations with primary LUAD. Moreover, transformed sarcomatoid carcinomas mimic the primary SC in terms of immunochemical and molecular features.

Conclusions

The transformation from lung adenocarcinoma to SC is a resistance mechanism wildly applied to inhibitors targeting different driver oncogenes. Immunotherapy plus chemotherapy shows potential to benefit patients with sarcomatoid transformation and warrants further study in larger cohorts.

Efficacy of immune checkpoint inhibitors in pulmonary sarcomatoid carcinoma and predictive potential of mutated TP53

OBJECTIVE

Pulmonary sarcomatoid carcinoma (PSC) is a rare, heterogeneous subgroup of non-small cell lung cancer (NSCLC). Patients with advanced PSCs have poor survival due to resistance to chemotherapy and radiotherapy, and narrow access to targeted therapy. Immune checkpoint inhibitors (ICIs) offer new hope, whereas data on their effectiveness is limited.

METHODS

This retrospective study collected medical records of patients with advanced PSCs from January 2010 to March 2024 across two centers in China, analyzing demographic, treatment, and survival data. Sixty cases were included.

RESULTS

In tumors tested for PD-L1 expression, 80 % had PD-L1 positivity, and 60 % exhibited TPS ≥ 50 %. The most frequently mutated genes in PSCs were TP53 (25.9 %), KRAS (22.8 %), MET (7.4 %), BRAF (7.4 %), CDKN2A/B (7.4 % each), and EGFR (6.2 %). Median OS of patients with advanced PSCs receiving anti-PD-1 or anti-PD-L1 antibodies in any line was significantly longer compared to those who did not (NR vs. 11.2 months, p = 0.015). ICI application was an independent favorable factor for the prognosis of patients diagnosed with advanced PSC (HR 0.32, p = 0.008). In the subgroup treated with ICI-based therapies, ORR and DCR were 34.5 % and 82.8 %, respectively. The mPFS and mOS of ICI-based therapies were 12.5 and 16.0 months, respectively. TP53 mutations and PD-L1 TPS ≥ 80 % were associated with prolonged PFS (p = 0.021, p = 0.035) and OS (p = 0.013 and p = 0.018).

CONCLUSIONS

Positive or high PD-L1 expression was prevalent in advanced PSCs. Anti-PD-1 or anti-PD-L1 antibodies were associated with favorable prognosis, and should be considered a key treatment option for patients with advanced PSC lacking actionable driver mutations. In addition to PD-L1 expression, TP53 mutations have the potential to predict the efficacy of ICIs in treating patients with advanced PSC and its prognostic significance deserves further validation in larger prospective studies.

Heterogeneity in advanced pulmonary sarcomatoid carcinoma and its efficacy to immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) have improved the prognosis of patients with non-small cell lung cancer but rarely been explored in pulmonary sarcomatoid carcinoma (PSC). This multicenter study aimed to evaluate the effectiveness of ICIs for PSC and its underlying mechanism.

METHODS

Advanced PSC who received ICIs between August 2018 and May 2022 from 11 centers in China were included. Clinical characteristics and treatment information were collected. Whole-exome sequencing (WES) and whole transcriptome sequencing were conducted on pre-treatment samples to explore the mechanism.

RESULTS

113 patients with PSC were enrolled, the median PFS for patients receiving ICIs therapy was 8.77 months (95 % confidence interval, 4.21 to 13.32). Combining ICIs with anti-angiogenic agents significantly increased PFS (p = 0.04). Liver metastasis and combination therapy with anti-angiogenic agents were independent risk factors for PFS (Hazard Ratio [HR] = 3.652, p = 0.019 and HR = 0.435, p = 0.017, respectively). WES showed that PSC presented with a TMB of 6.3 mutations per million base pairs. High expression of TNFα signaling and glycolysis related gene showed a better prognosis.

CONCLUSIONS

ICIs showed promising benefits for advanced PSC, and the addition of anti-angiogenic therapy might be a more effective treatment strategy for this disease.

Case report: Successful treatment of advanced pulmonary sarcomatoid carcinoma with BUBIB-ALK rearrangement and KRAS G12C mutation by sintilimab combined with anlotinib

Pulmonary sarcomatoid carcinoma (PSC) is a rare and aggressive subtype of non-small cell lung cancer (NSCLC) that is characterized by poor differentiation and invasiveness. According to the World Health Organization, PSC exhibits sarcoma or sarcomatoid differentiation and typically presents with an insidious onset, lacking specific symptoms and signs. It is associated with high malignancy, early metastasis, short survival time, and a poor prognosis. Treatment for PSC follows a similar approach to NSCLC; however, it presents significant challenges due to its high resistance to chemotherapy. Previous research has demonstrated the coexistence of two or more target mutations in PSC, and the presence of multiple mutations is correlated with higher mortality rates compared to single mutations. This is supported by our case study of a male patient with advanced BUBIB-ALK rearrangement and KRAS G12C missense mutation. There is currently no standard treatment protocol available for patients with this condition. The patient showed rapid progression after 1 month of alectinib treatment and was intolerant to paclitaxel + cisplatin chemotherapy. Following this, successful disease control was achieved with a combination therapy of sintilimab and anlotinib. The patient achieved a progression-free survival (PFS) of over 20 months, and long-term follow-up is still ongoing for the patient. Based on our clinical experience, the combination of anlotinib and programmed death-1 (PD-1) inhibitors may be a promising strategy for PSC patients, particularly those with multi-target mutations who do not respond to ALK-TKI and are resistant to chemotherapy.

Effectiveness and Safety of Immune Checkpoint Inhibitors Alone or in Combination With Chemotherapy in Pulmonary Sarcomatoid Carcinoma

Introduction

Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of lung cancer associated with poor prognosis and resistance to conventional chemotherapy. Immune checkpoint inhibitors (ICIs), alone or in combination with chemotherapy, were found to have clinical benefits in PSC in recent studies. Nevertheless, because these studies included a small number of patients owing to disease rarity, larger studies are needed to evaluate the effectiveness and safety of ICI-based therapy for PSC.

Methods

This multicenter retrospective study evaluated patients with ICI-naive advanced or metastatic PSC who were treated with ICI-based therapy at 25 hospitals in Japan.

Results

A total of 124 patients were evaluated. The overall response rate, median progression-free survival (PFS), and median overall survival (OS) were 59.0%, 10.5 months, and 32.8 months, respectively. The PFS and OS rates at 24 months were 35.3% and 51.5%, respectively. Programmed death-ligand 1 expression, concomitant chemotherapy, and the treatment line were not significantly associated with PFS or OS. Immune-related adverse events (irAEs) were observed in 70 patients (56.5%), including 30 (24.2%) with grade 3 to 5 events. Patients with mild irAEs (grades 1-2) had longer PFS and OS than did those with severe (grades 3-5) or no irAEs. In a multivariate analysis, any-grade irAEs and the absence of liver metastases were independently associated with PFS, whereas any-grade irAEs and Eastern Cooperative Oncology Group performance status less than or equal to 1 were independently associated with OS.

Conclusions

ICI-based therapy was found to have promising effectiveness in patients with advanced or metastatic PSC, regardless of programmed death-ligand 1 expression, concomitant chemotherapy, or treatment line.

Common clinicopathological and immunological features of sarcomatoid carcinoma across organs: A histomorphology-based cross-organ study

Sarcomatoid carcinoma (SC), which can occur in any organ, is a rare disease. To elucidate common characteristics of SC beyond organs, we evaluated clinicopathological and immunological features of SC defined by the single histological criterion beyond organs compared to randomly matched conventional carcinoma (non-SC) adjusted for the disease stage. Immunological features were assessed by multiplex immunohistochemistry, comparing immune cell density in tumor tissues and tumor programmed death-ligand 1 (PD-L1) expression. A total of 101 patients with SC or non-SC (31 lung, 19 esophagus, 22 pancreas, 15 liver, 4 bile duct, 6 kidney, 2 uterus and 2 ovary) were identified among 7197 patients who underwent surgery at our institute (1997-2020). SC was significantly associated with worse survival (HR: 1.571; 95% CI: 1.084-2.277; P = .017). The frequency of postoperative progression within 6 months was significantly higher for SC patients (54% vs 28%; P = .002). The immune profiling revealed the densities of CD8+ T cells (130 vs 72 cells/mm2 ; P = .004) and tumor-associated macrophages (566 vs 413 cells/mm2 ; P < .0001) and the tumor PD-L1 expression score (40% vs 5%; P < .0001) were significantly higher in SCs than in non-SCs. Among 73 SC patients with postoperative progression, multivariate Cox regression analysis showed that immunotherapy tended to be associated with favorable survival (HR: 0.256; 95% CI: 0.062-1.057; P = .060). Collectively, SCs shared clinicopathological and immunological features across organs. Our study can initiate to standardize the pathological definition of SC and provide a rationale for the investigation and development for this rare disease in a cross-organ manner.

Pembrolizumab combined with anlotinib improves therapeutic efficacy in pulmonary sarcomatoid carcinoma with TMB-H and PD-L1 expression: a case report and literature review

Background

Pulmonary sarcomatoid carcinoma (PSC) is a unique subtype of non-small cell lung cancer (NSCLC) with a high degree of malignancy and poor therapeutic effects. With the widespread use of immune checkpoint inhibitors (ICIs) in recent years, few studies have reported that immunotherapy is effective against PSC. As a multi-target anti-vascular targeting agent, anlotinib showed a better anti-tumor effect in various cancer species. The paper reported the therapeutic and side effects of pembrolizumab combined with anlotinib in a patient with advanced PSC.

Case presentation

This is a 73 year old female patient who underwent thoracoscopy right upper lobectomy and was diagnosed as locally advanced PSC. However, the patient experienced tumor recurrence and metastasis 7 weeks after surgery and was unable to tolerate chemoradiotherapy. Moreover, she detected TP53 mutation and found that tumor mutation burden (TMB) and PD-L1 were high expression. Therefore, the patient received pembrolizumab combined with anlotinib treatment. After 15 cycles of treatment, the tumor significantly shrank with no tumor activity. The evaluation of tumor efficacy is partial response (PR). During the treatment period, she experienced one-degree thyroid-stimulating hormone elevation and two-degree hand-foot syndrome. Pembrolizumab and anlotinib was continued for two years as a maintenance treatment. The patient had a good quality of life and no disease progression was observed. Currently, the patient is still alive without tumor progression and has overall survival exceeding 45 months and toxic side effects were tolerable.

Conclusions

Combining ICIs and anti-angiogenic targeted therapy has brought new hope in treating advanced PSC. Additionally, TMB and PD-L1 expression could be potential predictive biomarkers of the efficacy in advanced PSC with immunotherapy.

Anlotinib combined with pembrolizumab as first-line treatment for advanced pulmonary sarcomatoid carcinoma: a case report and literature review

Pulmonary sarcomatoid carcinoma (PSC) is an uncommon variant of non-small cell lung cancer (NSCLC), known for its unfavorable prognosis. Previous studies have elucidated that PSC generally exhibits a significant expression of programmed death-ligand 1 (PD-L1), an elevated tumor mutation burden, and marked vascular invasion. These factors imply the possible effectiveness of treatments like immunotherapy and anti-angiogenic therapy. The subject of this case was a 65-year-old male diagnosed with advanced PSC, characterized by high PD-L1 expression and devoid of known driver gene mutations. Owing to the restrictions imposed by the COVID-19 pandemic, the patient initially underwent home-based treatment with anlotinib, which led to symptomatic improvement after a single treatment cycle. Subsequent hospitalization allowed for the administration of anlotinib plus Pembrolizumab, resulting in a partial response. Radiotherapy was necessitated due to local disease progression. But after 15 cycles of treatment with Pembrolizumab, hyperprogression was observed. The patient's overall survival spanned 14 months, with no evident adverse reactions to the medications. Genomic analysis revealed potential associations between treatment efficacy and mutations in the TP53, NF1, and MET genes. This case underscores the effectiveness and safety of a first-line treatment regimen combining pan-target anti-angiogenic therapy (anlotinib) with anti-tumor immunotherapy.

Targeted therapy for rare lung cancers: Status, challenges, and prospects

Lung cancer causes the most cancer-related deaths worldwide. In recent years, molecular and immunohistochemical techniques have rapidly developed, further inaugurating an era of personalized medicine for lung cancer. The rare subset of lung cancers accounts for approximately 10%, each displaying distinct clinical characteristics. Treatments for rare lung cancers are mainly based on evidence from common counterparts, which may lead to unsolid clinical benefits considering intertumoral heterogeneity. The increasing knowledge of molecular profiling of rare lung cancers has made targeting genetic alterations and immune checkpoints a powerful strategy. Additionally, cellular therapy has emerged as a promising way to target tumor cells. In this review, we first discuss the current status of targeted therapy and preclinical models for rare lung cancers, as well as provide mutational profiles by integrating the results of existing cohorts. Finally, we point out the challenges and future directions for developing targeted agents for rare lung cancer.

Integrated Clinical, Molecular and Immunological Characterization of Pulmonary Sarcomatoid Carcinomas Reveals an Immune Escape Mechanism That May Influence Therapeutic Strategies

Pulmonary sarcomatoid carcinoma (PSC) has highly aggressive biological behaviour and poor clinical outcomes, raising expectations for new therapeutic strategies. We characterized 179 PSC by immunohistochemistry, next-generation sequencing and in silico analysis using a deep learning algorithm with respect to clinical, immunological and molecular features. PSC was more common in men, older ages and smokers. Surgery was an independent factor (p < 0.01) of overall survival (OS). PD-L1 expression was detected in 82.1% of all patients. PSC patients displaying altered epitopes due to processing mutations showed another PD-L1-independent immune escape mechanism, which also significantly influenced OS (p < 0.02). The effect was also maintained when only advanced tumour stages were considered (p < 0.01). These patients also showed improved survival with a significant correlation for immunotherapy (p < 0.05) when few or no processing mutations were detected, although this should be interpreted with caution due to the small number of patients studied. Genomic alterations for which there are already approved drugs were present in 35.4% of patients. Met exon 14 skipping was found more frequently (13.7%) and EGFR mutations less frequently (1.7%) than in other NSCLC. In summary, in addition to the divergent genomic landscape of PSC, the specific immunological features of this prognostically poor subtype should be considered in therapy stratification.

SMARCA4 as a support for the differential diagnosis of poorly differentiated lung carcinomas

Among non-small cell lung cancers (NSCLCs), sarcomatoid carcinomas account for 3%. They are rare tumours with a poor prognosis, classified into three subgroups, namely pleomorphic carcinoma, pulmonary blastoma and carcinosarcoma. In the 5th edition of WHO Classification of Thoracic Tumours more space is given to SMARC4-deficient lung cancers. Although studies on SMARCA4-deficient lung tumours are limited, a small percentage of SMARCA4 loss is present within NSCLCs. This finding is clinically relevant, as the loss of the SMARCA4 gene is associated with a worse prognosis. In our study, we analysed the presence of the main catalytic subunit of the SMARCA4 gene, the BRG1 protein, in 60 sarcomatoid lung tumours. The results of our study show that 5.3% of sarcomatoid carcinomas have BRG1-loss in tumour cells, proving that a non-negligible amount of lung sarcomatoid carcinomas are SMARCA4-deficient. These data open the debate on the necessity of including the detection of SMARCA4 within a standardised immunohistochemical panel.

Demographics and Clinicopathologic Profile of Pulmonary Sarcomatoid Carcinoma with Survival Analysis and Genomic Landscape

Background: Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small cell lung cancer (NSCLC) with an aggressive clinical nature and poor prognosis. With novel targeted therapeutics being developed, new ways to effectively treat PSC are emerging. In this study, we analyze demographics, tumor characteristics, treatment modalities, and outcomes of PSC and genetic mutations in PSC. Methods: Data from the Surveillance, Epidemiology, and End Results (SEER) database were reviewed to analyze cases of pulmonary sarcomatoid carcinoma from 2000 to 2018. The molecular data with the most common mutations in PSC were extracted from the Catalogue Of Somatic Mutations in Cancer (COSMIC) database. Results: A total of 5259 patients with PSC were identified. Most patients were between 70 and 79 years of age (32.2%), male (59.1%), and Caucasian (83.7%). The male-to-female ratio was 1.45:1. Most tumors were between 1 and 7 cm in size (69.4%) and poorly differentiated (grade III) (72.9%). The overall 5-year survival was 15.6% (95% confidence interval (95% CI) = 14.4-16.9)), and the cause-specific 5-year survival was 19.7% (95% CI = 18.3-21.1). The five-year survival for those treated with each modality were as follows: chemotherapy, 19.9% (95% CI = 17.7-22.2); surgery, 41.7% (95% CI = 38.9-44.6); radiation, 19.1% (95% CI = 15.1-23.5); and multimodality therapy (surgery and chemoradiation), 24.8% (95% CI = 17.6-32.7). On multivariable analysis, age, male gender, distant stage, tumor size, bone metastasis, brain metastasis, and liver metastasis were associated with increased mortality, and chemotherapy and surgery were associated with reduced mortality (p < 0.001). The best survival outcomes were achieved with surgery. The most common mutations identified in COSMIC data were TP53 31%, ARID1A 23%, NF1 17%, SMARCA4 16%, and KMT2D 9%. Conclusions: PSC is a rare and aggressive subtype of NSCLC, usually affecting Caucasian males between 70 and 79. Male gender, older age, and distant spread were associated with poor clinical outcomes. Treatment with surgery was associated with better survival outcomes.

Complete response to chemoimmunotherapy with bevacizumab in synchronous multiple primary cancers: pulmonary adenocarcinoma and sarcomatoid carcinoma

A small percentage of patients have multiple synchronous primary cancers at presentation. In the last five years, many regimens associated with immunotherapy and chemotherapy were approved for first-line metastatic non-small-cell lung cancer (NSCLC) and other solid tumors, but the study of immunotherapy when multiple cancers are present in one patient remains incomplete. Next-generation sequencing biomarkers and immunotherapy markers including PD-L1 can be effectively utilized in the diagnosis and treatment plan for multiple synchronous primary cancers. Immune biomarkers and PD-L1 expression warrant individualized treatments in synchronous primary adenocarcinoma and pulmonary sarcomatoid carcinoma. We describe the case of a patient with pulmonary sarcomatoid carcinoma and lung adenocarcinoma, metastatic to brain de novo. The patient achieved a complete response after only three cycles of carboplatin, paclitaxel, bevacizumab, and atezolizumab and remains free of any evidence of disease after 18 mo of maintenance therapy.

Immune checkpoint inhibitors plus chemotherapy in patients with locally advanced or metastatic pulmonary sarcomatoid carcinoma: a multicentric real-world study

INTRODUCTION

Immune checkpoint inhibitors (ICIs) have demonstrated promising efficacy as monotherapy in patients with pulmonary sarcomatoid carcinoma (PSC). We performed the current multi-institutional, real-world study to assess the efficacy of ICIs plus chemotherapy in patients with PSC.

METHODS

All consecutive patients with locally advanced or metastatic PSC from three centers treated with ICIs between January 2018 and July 2021 were enrolled. Programmed death ligand 1 (PD-L1) expression was stained and evaluated using immunohistochemical with 22C3. Single-cell RNA sequencing (scRNA-seq) was performed in two patients with PSC and two patients with adenocarcinoma to understand the cell-type-specific transcriptome landscape of cancer cells and tumor microenvironment (TME) of PSC.

RESULTS

A cohort of 42 PSC patients was identified. In the overall population, the objective response rate (ORR) was 73.8%, median progression-free survival (mPFS) was 10.3 months and median overall survival was not reached and 2-year survival rate was 51.2%. For 34 treatment-naïve patients who received first-line ICIs plus chemotherapy, the ORR was 70.6%, mPFS was 10.3 months and 2-year survival rate was 57.8%. In patients with PD-L1 tumor proportion score (TPS) < 1%, 1-49%, and ⩾50%, the ORR was 33.3%, 72.7%, and 85.7% and mPFS was 6.0, 6.7, and 10.3 months, respectively. Notably, two patients with transformed PSC from lung adenocarcinoma after epidermal growth factor receptor-tyrosine kinase inhibitor treatment also responded well to ICIs plus chemotherapy. scRNA-seq revealed immune-cell-inflamed TME, lower intratumoral heterogeneity, and activated immune response pathway in PSC.

CONCLUSIONS

Our study demonstrated remarkable efficacy of ICIs plus chemotherapy as first-line therapy for patient with locally advanced or metastatic PSC.

The efficacy and safety analysis of first-line immune checkpoint inhibitors in pulmonary sarcomatoid carcinoma

Background

Pulmonary sarcomatoid carcinoma (PSC) is a rare and aggressive disease without standardized treatment strategies. The efficacy of second-line or beyond immune checkpoint inhibitors (ICIs) has been proven in recent studies, whereas the evidence for first-line immunotherapy for PSC is still limited to case reports and remains poorly understood.

Materials and methods

This was a multicenter, retrospective analysis of 21 patients with a histological diagnosis of PSC who received ICI as first-line therapy from January 2019 to March 2022. The expression of PD-L1 was evaluated by immunohistochemistry (IHC) using the monoclonal antibody 22C3. Low and high PD-L1 expressions were defined using the tumor proportion score (TPS), with cutoffs of 1 and 50%, respectively.

Results

All eight patients had PD-L1 positivity who underwent PD-L1 expression assessment, and six patients (6/8, 75.0%) had high PD-L1 expression. Among the 21 PSC patients, seven received tislelizumab, six received camrelizumab, four received sintilimab, three received pembrolizumab, and one received durvalumab. Among them, 18 PSCs received combination therapy, whereas another three PSCs received immunotherapy alone. Out of the 21 PSC patients, 12 (57.1%) achieved a partial response (PR), and five patients had stable disease (SD) as the best response, whereas four PSCs experienced dramatic progressive disease (PD). The median progression-free survival (PFS) was 9.2 (95% CI [4.3, 14.1]) months, and the median OS was 22.8 (95% CI [4.0, 41.5]) months. Among the three treatment groups (immunotherapy alone, immunotherapy combined with anlotinib, and chemoimmunotherapy), the median PFS was 8.0, 9.4, and 9.6 months, and the median OS was 19.0, 22.8, and 30.6 months, respectively. There was no difference in PFS and OS between the three treatment regimen groups (P = 0.86 and P = 0.34, respectively) and different immunotherapies (P = 0.10 and P = 0.23, respectively). No serious adverse events (grade ≥ 3) were noted.

Conclusion

First-line immunotherapy has promising therapeutic potential in the treatment of PSC. More studies are warranted to confirm these findings.

Real-world treatment patterns and outcomes among patients with advanced non-small-cell lung cancer with spindle cell and/or giant cell carcinoma

Objectives

A definitive diagnosis of pulmonary sarcomatoid carcinoma cannot be made with small biopsies. In clinical practice, a diagnosis of advanced non-small-cell lung cancer with spindle cell and/or giant cell carcinoma (NSCLCsg), or possible sarcomatoid carcinoma, is acceptable. Therefore, we aimed to investigate the treatment patterns and outcomes of advanced NSCLCsg.

Materials and methods

Between 01 January 2012 and 01 April 2021, patients with pathologically proven advanced NSCLCsg were enrolled. The choice of treatment was based on clinician discretion.

Results

In all, 101 patients with advanced NSCLCsg were enrolled. In total, 77 (76.2%) patients received at least one line of systemic therapy; 44 patients (43.1%) had received platinum doublet chemotherapy; 27 (26.7%) patients had been treated with targeted therapies; and 23 patients (22.8%) had been given an immune checkpoint inhibitor (ICI). The median overall survival (OS) was 6.3 months [95% confidence interval (CI): 3.6-9.0 months]. Excluding patients without systemic therapy, patients who had received an ICI had better OS (median: 18.2 months) than those who had not (median 3.8 months, log-rank test p = 0.002). No significant difference in OS was detected between patients who had or had not received platinum doublet chemotherapy (log-rank test p = 0.279), or targeted therapy (log-rank test p = 0.416). Having received any systemic therapy [hazard ratio (HR): 0.33, 95% CI: 0.18-0.61, p < 0.0001) and ICI (HR: 0.38, 95% CI: 0.19-0.78, p = 0.008) were independent factors for better OS. Patients with programmed death ligand-1 (PD-L1) expression ⩾50% had better OS than those with PD-L1 expression <50% (HR: 0.51, 95%: 0.30-0.86, p = 0.012).

Conclusion

Although advanced NSCLCsg has a poor survival outcome, our results showed that ICI may prolong OS in patients with advanced NSCLCsg. Further prospective studies are warranted to gain more understanding of the role of ICI in this specific patient population.

Significant response of pulmonary sarcomatoid carcinoma with obstructive atelectasis to treatment with the PD-1 inhibitor camrelizumab combined with transbronchial cryoablation: A case report and literature review

Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small cell lung cancer with high malignancy and poor prognosis. Chemotherapy or radiotherapy do not usually provide satisfactory results in patients with PSC, especially in those with advanced-stage cancer. Targeted therapy and immunotherapy are more precise therapies that may be effective in the treatment of PSC; however, further research is needed. Here, we present a case of stage III PSC with obstructive atelectasis, which is more challenging and hinders treatment. Treatment with the PD-1 inhibitor camrelizumab and transbronchial cryoablation showed significant clinical efficacy. This type of combined treatment has not been reported previously for PSC. Thus, this case may provide a valuable reference for future clinical practice and research.

Genomic characterization of undifferentiated sarcomatoid carcinoma of the pancreas

Undifferentiated sarcomatoid carcinoma (USC) of the pancreas is a rare but especially aggressive variant of pancreatic ductal adenocarcinoma (PDAC), composed of at least 80% of sarcomatoid cells. This study aimed to elucidate its clinicopathological and molecular features. The study cohort included 10 patients with pancreatic USC. Clinicopathological parameters were determined for each patient. The molecular profile was investigated using next-generation sequencing (NGS). Histologically, all tumors were hypercellular neoplasms with spindle-shaped or sarcomatoid cells. All patients showed vascular and perineural invasion. Most patients had a poor prognosis. NGS showed important similarities with conventional PDAC, including frequent alterations in the classic PDAC drivers, KRAS (100% of cases), TP53 (90%), and CDKN2A (60%). There were also some important distinctions from conventional PDAC: 1) SMAD4, a typical PDAC driver gene, was mutated in only one case (10%); 2) Another distinctive molecular feature was the recurrent KRAS amplification (30% of cases), which is very rare in conventional PDAC. It has been previously reported in another subtype of pancreatic undifferentiated carcinoma, the rhabdoid variant, and may be a key event leading to the acquisition of an undifferentiated phenotype in a subgroup of cases; 3) Lastly, in two different cases, we detected two potentially actionable targets, not belonging to the typical PDAC molecular landscape, such as MCL1 amplification and POLQ mutation. Our study sheds light on this rare tumor type, which shows aggressive biological behavior and few druggable alterations. The most distinctive molecular features of pancreatic USC are the paucity of SMAD4 alterations and recurrent KRAS amplification.

Molecular and expressional characterization of tumor heterogeneity in pulmonary carcinosarcoma

The genetic concordance and heterogeneity of the two components of pulmonary carcinosarcoma (PCS), carcinoma, and sarcoma, have not been fully elucidated because of its rare occurrence. We performed targeted sequencing of the carcinoma and sarcoma components of four PCSs to identify genetic similarities and differences. Formalin-fixed paraffin-embedded tissue samples were macroscopically or microscopically dissected. DNA was extracted from each component, and genetic alterations were analyzed separately. Moreover, we performed RNA-seq analysis on both components of one PCS to compare differences in gene expression profiles. The carcinoma part consisted of adenocarcinoma in two cases, squamous cell carcinoma in one, and adenosquamous carcinoma in the last. TP53 mutation was observed in three samples from the trunk, although it was detected only in the sarcoma part in one case. No specific driver gene mutation was observed; however, KRAS mutations were observed in one case in the trunk. RNA-seq analysis revealed that the rhabdomyosarcoma component expressed various genes related to muscle development, whereas the carcinoma component did not; and that gene expression overall was completely different between the two components. Our study revealed that the two different components of PCS shared common gene mutations in most cases. Although gene expression was different among components, if driver genes such as KRAS were detected in PCS, molecular targeted therapy could be beneficial even when the tumor contains a sarcoma component.

Multimodality Treatment of Pulmonary Sarcomatoid Carcinoma: A Review of Current State of Art

Pulmonary sarcomatoid carcinoma (PSC) is an unconventional non-small-cell lung cancer (NSCLC) that is currently managed under guidelines used for conventional NSCLC and has poor survival. Surgery is the optimal choice for resectable PSC, and the prevalence of mutations in this type of tumor laid the foundation for novel systemic therapies such as targeted therapy and immunotherapy. PSC is resistant to chemotherapy and radiotherapy, and the effects of the 2 therapies are controversial. Targeted therapies have been reported to confer survival benefits, and savolitinib, an oral selective MET tyrosine-kinase inhibitor, has been approved in metastatic patients with MET exon 14 skipping mutations. Expression and positive rate of programmed death ligand 1 in PSC are high; our previous research has also revealed a high mutational burden and a T-cell-inflamed microenvironment of PSC. Correspondingly, immune checkpoint inhibitors have shown preliminary antitumor effects (overall response rates of 40.5% (15/37) and 31.6% (6/19) in two retrospective studies, respectively) in PSC patients. In summary, patients should receive operations at an early stage and multimodality treatments are needed to maximize the benefits of patients with advanced disease.

Daily Practice Assessment of KRAS Status in NSCLC Patients: A New Challenge for the Thoracic Pathologist Is Right around the Corner

Simple Summary

RAS mutation is the most frequent oncogenic alteration in human cancers and KRAS is the most frequently mutated, notably in non-small cell lung carcinomas (NSCLC). Various attempts to inhibit KRAS in the past were unsuccessful in these latter tumors. However, recently, several small molecules (AMG510, MRTX849, JNJ-74699157, and LY3499446) have been developed to specifically target KRAS G12C-mutated tumors, which seems promising for patient treatment and should soon be administered in daily practice for non-squamous (NS)-NSCLC. In this context, it will be mandatory to systematically assess the KRAS status in routine clinical practice, at least in advanced NS-NSCLC, leading to new challenges for thoracic oncologists.

Abstract

KRAS mutations are among the most frequent genomic alterations identified in non-squamous non-small cell lung carcinomas (NS-NSCLC), notably in lung adenocarcinomas. In most cases, these mutations are mutually exclusive, with different genomic alterations currently known to be sensitive to therapies targeting EGFR, ALK, BRAF, ROS1, and NTRK. Recently, several promising clinical trials targeting KRAS mutations, particularly for KRAS G12C-mutated NSCLC, have established new hope for better treatment of patients. In parallel, other studies have shown that NSCLC harboring co-mutations in KRAS and STK11 or KEAP1 have demonstrated primary resistance to immune checkpoint inhibitors. Thus, the assessment of the KRAS status in advanced-stage NS-NSCLC has become essential to setting up an optimal therapeutic strategy in these patients. This stimulated the development of new algorithms for the management of NSCLC samples in pathology laboratories and conditioned reorganization of optimal health care of lung cancer patients by the thoracic pathologists. This review addresses the recent data concerning the detection of KRAS mutations in NSCLC and focuses on the new challenges facing pathologists in daily practice for KRAS status assessment.

The treatment of advanced pulmonary sarcomatoid carcinoma

Pulmonary sarcomatoid carcinoma (PSC) is a pathological subtype of non-small cell lung cancer. Although the incidence of PSC in lung cancer is very low, it is an aggressive cancer, leading to a poor prognosis. Currently, there is no standard treatment for advanced PSC. Targeted therapy can be used for patients with MET exon 14 mutations and patients with other driver gene mutations may also benefit from treatment. The emergence of immune checkpoint inhibitors also provides potential options for advanced PSC treatment, but more clinical data is needed. Additionally, more research may be warranted to explore the effects of chemotherapy, radiotherapy and antiangiogenic therapy. In this review, the authors summarize the research regarding the treatment of advanced PSC.

Report of Two Pulmonary Sarcomatoïd Carcinoma Cases With Highlights on the Computed Tomography Features

Pulmonary sarcomatoïd carcinomas are a heterogeneous group of poorly differentiated non-small cell tumors with a sarcomatous component. On imaging, they appear as peripheral or central masses, sometimes excavated. We report two cases of pulmonary sarcomatoïd lung carcinoma. The first case involves a 73-year-old active smoker who presented with dyspnea. A computed tomography (CT) scan showed a large locally advanced left lower lobar tumor process. A CT-guided biopsy was performed and the histopathological examination concluded a pulmonary sarcomatoïd carcinoma. The second case involves a 52-year-old chronic smoker who presented with hemoptysis. CT pulmonary angiography showed an excavated right upper lobar tumor. Histologic work-up of the right upper lobectomy piece objectified a pulmonary sarcomatoïd carcinoma. Pulmonary sarcomatoïd carcinoma has a nonspecific appearance on imaging and should be a part of imaging differential diagnoses in front of a large, lobulated, highly invasive lung tumor with or without excavation.