Pulmonary Sarcomatoid Carcinomas: A Review

Identification of CT Features to Differentiate Pulmonary Sarcoma from Carcinoma

Background  Primary lung sarcoma (PLS) differs in management protocols and prognosis from the more common primary lung carcinoma (PLC). It becomes imperative to raise a high index of suspicion on radiological and pathological features. Purpose  The aim of this study is to highlight the variable imaging appearances of PLS compared with PLC, which impacts radiologic - pathologic correlation. Materials and Methods  A retrospective observational study of 68 patients with biopsy-proven lung tumors who underwent baseline imaging at our tertiary care cancer hospital was conducted between January 2018 and March 2022. The patient details and imaging parameters of the mass on contrast-enhanced computed tomography (CECT) were recorded and analyzed for patients with PLS and compared with PLC. Follow-up imaging was available in 9/12 PLS and 52/56 PLC patients. Results  Among 12 patients with PLS, 5 patients had synovial sarcoma on histopathology. PLS was seen in patients with a mean age of 40.8 years; the mass showed a mean size of 13.2 cm, lower lobe (75%), parahilar (75%), hilar involvement (41.7%), oval shape (41.7%), circumscribed (25%) or lobulated (75%) margins, lower mean postcontrast attenuation of 57.3 HU, fissural extension (50%), calcification (50%), and no organ metastasis other than to the lung. PLC (56 patients) was seen in the elderly with a mean age of 54.8 years; the mass showed a mean size of 5.7 cm, irregular shape (83.9%), spiculated margins (73.2%), higher mean postcontrast attenuation (77.3 HU), chest wall infiltration (30.4%), and distant metastasis (58.9%) at baseline imaging. A statistically significant difference ( p  < 0.05) was seen between sarcoma and carcinoma in the mean age, size, site, shape, margins, postcontrast attenuation, presence of calcifications, fissural extension, and distant metastasis. Conclusion  The distinct imaging features of sarcoma help in differentiating it from carcinoma. This can also be used to corroborate with histopathology to achieve concordance and guide clinicians on further approach.

Utility of Immunohistochemistry in the Diagnosis of Pleuropulmonary and Mediastinal Cancers: A Review and Update

CONTEXT.—

Immunohistochemistry has become a valuable ancillary tool for the accurate classification of pleuropulmonary and mediastinal neoplasms necessary for therapeutic decisions and predicting prognostic outcome. Diagnostic accuracy has significantly improved because of the continuous discoveries of tumor-associated biomarkers and the development of effective immunohistochemical panels.

OBJECTIVE.—

To increase the accuracy of diagnosis and classify pleuropulmonary neoplasms through immunohistochemistry.

DATA SOURCES.—

Literature review and the author's research data and personal practice experience.

CONCLUSIONS.—

This review article highlights that appropriately selecting immunohistochemical panels enables pathologists to effectively diagnose most primary pleuropulmonary neoplasms and differentiate primary lung tumors from a variety of metastatic tumors to the lung. Knowing the utilities and pitfalls of each tumor-associated biomarker is essential to avoid potential diagnostic errors.

A case report: A new promising treatment for pulmonary sarcomatoid carcinoma - Tislelizumab and Anlotinib combined with local radiotherapy

Background

Pulmonary sarcomatoid carcinoma (PSC) is a rare pathological type of non-small cell lung cancer, only occurs in 0.1%-0.4 % of lung cancer patients. It has a poor prognosis and shows low response to conventional chemotherapy. Target therapy, immunotherapy, and other new approaches are worth exploring in PSC. Recently, patients with MET ex14 skipping mutation can obtain good therapeutic efficacy through target therapy. But there was no definitive treatment for patients without this special mutation.

Case description

Now, we report a female PSC patient without MET ex14 skipping mutation in the cT4N2M1 stage treated with Tislelizumab and Anlotinib obtained remarkable effect for more than 2 years. Significantly, in this case, immunotherapy and antiangiogenic therapy continued to prolong the survival time of more than 10 months for the patient after being treated by local radiotherapy. This is the first case that reported the effectiveness of immunotherapy and antiangiogenic therapy combined with local radiotherapy in treating PSC and achieved more long-term clinical efficacy than other treatments.

Conclusions

Thus, immunotherapy and antiangiogenic therapy combined with local radiotherapy may bring new hope to advanced PSC patients and is worth conducting further research. It provided an effective reference for the treatment of advanced PSC patients without METex14 skipping mutation. Moreover, this case also demonstrated the synergistic effect of radiotherapy and immunotherapy.

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.

An advanced pulmonary sarcomatoid carcinoma patient harboring a BRAFV600E mutation responds to dabrafenib and trametinib: a case report and literature review

Background

The pulmonary sarcomatoid carcinoma (PSC) is a rare and aggressive subtype of NSCLC with rapid progression and poor prognosis, and is resistant to conventional chemotherapy. Most PSC cases have potential targetable genomic alterations. Approximately 7% of PSC patients have BRAF mutations, and the efficacy of dabrafenib and trametinib in BRAFV600E mutated PSC is unclear.

Case presentation

Our report describes a patient with mutated BRAFV600E PSC who underwent surgery and adjuvant chemotherapy early but quickly relapsed. Both chemotherapy and immunotherapy were ineffective for him, combined dabrafenib and trametinib produced a 6-month progression-free survival, and a partial response was observed in the tumor response evaluation. As a result of financial pressure, he stopped taking the targeted drugs, and his disease rapidly progressed.

Conclusion

Dabrafenib combined with trametinib provides partial remission in patients with advanced PSC with BRAFV600E mutations, and large-scale NGS panels could offer more options for PSC treatment.

Individual risk and prognostic value prediction by machine learning for distant metastasis in pulmonary sarcomatoid carcinoma: a large cohort study based on the SEER database and the Chinese population

Background

This study aimed to develop diagnostic and prognostic models for patients with pulmonary sarcomatoid carcinoma (PSC) and distant metastasis (DM).

Methods

Patients from the Surveillance, Epidemiology, and End Results (SEER) database were divided into a training set and internal test set at a ratio of 7 to 3, while those from the Chinese hospital were assigned to the external test set, to develop the diagnostic model for DM. Univariate logistic regression was employed in the training set to screen for DM-related risk factors, which were included into six machine learning (ML) models. Furthermore, patients from the SEER database were randomly divided into a training set and validation set at a ratio of 7 to 3 to develop the prognostic model which predicts survival of patients PSC with DM. Univariate and multivariate Cox regression analyses have also been performed in the training set to identify independent factors, and a prognostic nomogram for cancer-specific survival (CSS) for PSC patients with DM.

Results

For the diagnostic model for DM, 589 patients with PSC in the training set, 255 patients in the internal and 94 patients in the external test set were eventually enrolled. The extreme gradient boosting (XGB) algorithm performed best on the external test set with an area under the curve (AUC) of 0.821. For the prognostic model, 270 PSC patients with DM in the training and 117 patients in the test set were enrolled. The nomogram displayed precise accuracy with AUC of 0.803 for 3-month CSS and 0.869 for 6-month CSS in the test set.

Conclusion

The ML model accurately identified individuals at high risk for DM who needed more careful follow-up, including appropriate preventative therapeutic strategies. The prognostic nomogram accurately predicted CSS in PSC patients with DM.

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.

Clinical analysis of 78 pulmonary sarcomatoid carcinomas with surgical treatment

OBJECTIVE

To evaluate clinical factors influencing the postoperative pulmonary sarcomatoid carcinoma (PSCs) prognosis.

METHODS

We retrospectively evaluated patients with PSCs treated from October 2012 to October 2017. Kaplan-Meier survival curves were calculated using univariable analysis (log-rank test). Univariable/multivariable Cox regression analysis was also performed.

RESULTS

Mixed PSCs were most common (64.10%). Pure PSCs occurred more often with large tumors compared with mixed PSCs. Patients with vs without pleural retraction, respectively, had significantly worse overall survival (OS; 16 vs 23 months) and disease-free survival (DFS; 11 vs 20 months), and patients with airway dissemination had significantly shorter OS (14 vs 21 months) and DFS (11 vs 20 months). Patients with PSC with an adenocarcinoma component had favorable OS. Airway dissemination, pleural retraction, metastatic mediastinal lymph node (LN) number, and pathological tumor-node-metastasis (pTNM) stage were risk factors for short OS. Neither adjuvant chemotherapy nor adjuvant radiotherapy provided a survival advantage. Airway dissemination was an independent prognostic factor (odds ratio, 1.87; 95% confidence interval, 1.04-3.36).

CONCLUSION

Pure PSCs were more likely with large tumors compared with mixed PSCs. Airway dissemination, pleural retraction, and metastatic mediastinal LN number were associated with OS. Airway dissemination was an independent prognostic factor.

MET alterations in advanced pulmonary sarcomatoid carcinoma

Pulmonary sarcomatoid carcinoma (PSC) is a rare subset of NSCLC that accounts for about 0.5-1% of all primary lung carcinoma, and its malignant biological behavior is more aggressive than other pathological types of lung cancer. Recent studies have reported a variety of gene mutations associated with the occurrence, development and treatment of PSC, especially the mesenchymal-epithelial transition (MET) proto-oncogene alterations, including the exon 14 (METex14) skipping mutations as well as the amplification and overexpression of MET gene, which are associated with molecularly targeted therapy for PSC. METex14 skipping mutation is the most common and well-studied mutation type, occurring in about 22-31.8% of PSC patients, while the prevalence of MET amplification is reported as 4.8-13.6% and MET ovexpression is about 20.2%. Molecular pathology tests, including IHC and NGS, are valuable in determining the prognosis of patients with PSC and helping to determine the treatment. The existing clinical data have confirmed the efficacy of MET-TKI in PSC patients with MET alteration, among which the clinical study of Savolitinib has enrolled the largest proportion of PSC patients and achieved relatively good efficacy, but more clinical researches are still needed. The multi-disciplinary team may maximize the optimal treatment options for patients with the advanced PSC.

Adjuvant chemotherapy is not a decisive factor in improving the overall survival of pulmonary sarcoma: A population-based study

Objective

This study aimed to investigate the impact of adjuvant chemotherapy on overall survival (OS) for pulmonary sarcomatoid carcinoma (PSC) and non-small-cell lung cancer (NSCLC) cohorts and to identify its potential risk factors.

Methods

A retrospective analysis was performed by querying the Surveillance, Epidemiology, and End Results (SEER) database for patients diagnosed as having PSC (n=460) and NSCLC (n=140,467) from 2004 to 2015. The demographics, tumor characteristics, treatment modes, and survival were included in the scope of statistical analysis. Confounding factors were controlled by propensity score matching (PSM) analysis. Kaplan–Meier survival curves were performed to compare the effects of adjuvant chemotherapy on OS of the patients in the two cohorts (PSC vs. NSCLC). A multivariable Cox regression model was constructed, and Kaplan–Meier analysis on each variate was applied to predict risk factors associated with OS.

Results

When adjuvant chemotherapy approach was applied in the treatment of patients with PSC or adjusted NSCLC, respectively, an improved OS could be observed in the NSCLC cohort (p=0.017). For the entire PSC cohort, 1-, 3-, and 5-year OS were 25.43%, 13.04%, and 6.96%, respectively, compared with 41.96%, 17.39%, and 10.00%, respectively, for the new adjusted NSCLC cohort after PSM, which were statistically significant difference (p<0.001). Multivariable Cox regression analysis was performed on OS covering prognostic factors such as primary site (p=0.036), first malignant indicator (p<0.001), age at diagnosis (p<0.001), marital status at diagnosis (p=0.039), and high school education (p=0.045). Additionally, patients with the following parameters had the worse impact on OS: a poorly differentiated pathology (Grade III/IV, p=0.023), older age (p<0.001), liver or lung metastasis (p=0.004, p=0.029), and the number of lymph nodes removed <4 (p<0.001).

Conclusions

Adjuvant chemotherapy did not play a decisive role in improving the OS of PSC, while it was associated with improved OS of NSCLC.

Pten and p53 Loss in the Mouse Lung Causes Adenocarcinoma and Sarcomatoid Carcinoma

Simple Summary

Lung cancer is the world leading cause of cancer death. Therefore, a better understanding of the disease is needed to improve patient survival. In this work, we have deleted the tumor suppressor genes Pten and Trp53 in adult mouse lungs to analyze its impact on tumor formation. Double mutant mice develop Adenocarcinoma and Pulmonary Sarcomatoid Carcinoma, two different types of Non-Small Cell Carcinoma whose biological relationships are a matter of debate. The former is very common, with various models described and some therapeutic options. The latter is very rare with very poor prognosis, no effective treatment and lack of models reported so far. Interestingly, this study reports the first mouse model of pulmonary sarcomatoid carcinoma available for preclinical research.

Abstract

Lung cancer remains the leading cause of cancer deaths worldwide. Among the Non-Small Cell Carcinoma (NSCLC) category, Adenocarcinoma (ADC) represents the most common type, with different reported driver mutations, a bunch of models described and therapeutic options. Meanwhile, Pulmonary Sarcomatoid Carcinoma (PSC) is one of the rarest, with very poor outcomes, scarce availability of patient material, no effective therapies and no models available for preclinical research. Here, we describe that the combined deletion of Pten and Trp53 in the lungs of adult conditional mice leads to the development of both ADC and PSC irrespective of the lung targeted cell type after naphthalene induced airway epithelial regeneration. Although this model shows long latency periods and incomplete penetrance for tumor development, it is the first PSC mouse model reported so far, and sheds light on the relationships between ADC and PSC and their cells of origin. Moreover, human ADC show strong transcriptomic similarities to the mouse PSC, providing a link between both tumor types and the human ADC.

Omega-6 Polyunsaturated Fatty Acids Enhance Tumor Aggressiveness in Experimental Lung Cancer Model: Important Role of Oxylipins

Lung cancer is currently the leading cause of cancer death worldwide; it is often diagnosed at an advanced stage and bears poor prognosis. It has been shown that diet is an important environmental factor that contributes to the risk and mortality of several types of cancers. Intake of ω-3 and ω-6 PUFAs plays an important role in cancer risk and progression. Current Western populations have high consumption of ω-6 PUFAs with a ratio of ω-6/ω-3 PUFAs at 15:1 to 16.7:1 This high consumption of ω-6 PUFAs is related to increased cancer risk and progression. However, whether a diet rich in ω-6 PUFAs can contribute to tumor aggressiveness has not been well investigated. We used a murine model of pulmonary squamous cell carcinoma to study the aggressiveness of tumors in mice fed with a diet rich in ω-6 PUFAs and its relationship with oxylipins. Our results shown that the mice fed a diet rich in ω-6 showed a marked increase in proliferation, angiogenesis and pro-inflammatory markers and decreased expression of pro-apoptotic proteins in their tumors. Oxylipin profiling revealed an upregulation of various pro-tumoral oxylipins including PGs, HETEs, DiHETrEs and HODEs. These results demonstrate for the first time that high intake of ω-6 PUFAs in the diet enhances the malignancy of tumor cells by histological changes on tumor dedifferentiation and increases cell proliferation, angiogenesis, pro-inflammatory oxylipins and molecular aggressiveness targets such as NF-κB p65, YY1, COX-2 and TGF-β.

Molecular Pathology of Lung Cancer

This overview of the molecular pathology of lung cancer includes a review of the most salient molecular alterations of the genome, transcriptome, and the epigenome. The insights provided by the growing use of next-generation sequencing (NGS) in lung cancer will be discussed, and interrelated concepts such as intertumor heterogeneity, intratumor heterogeneity, tumor mutational burden, and the advent of liquid biopsy will be explored. Moreover, this work describes how the evolving field of molecular pathology refines the understanding of different histologic phenotypes of non-small-cell lung cancer (NSCLC) and the underlying biology of small-cell lung cancer. This review will provide an appreciation for how ongoing scientific findings and technologic advances in molecular pathology are crucial for development of biomarkers, therapeutic agents, clinical trials, and ultimately improved patient care.

Establishment of a Competing Risk Nomogram in Patients with Pulmonary Sarcomatoid Carcinoma

Background and aim: Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of nonsmall cell lung cancer with a poor prognosis. This study aimed to analyze the clinicopathological characteristics and survival outcomes among patients with PSC, lung squamous cell cancer (SCC), and lung adenocarcinoma (LAC), and to construct a competing risk nomogram for patients with PSC. Method: Data of 3 groups of patients diagnosed with PSC, SCC, or LAC from the surveillance, epidemiology, and end results (SEER) database between 1988 and 2015 were retrospectively reviewed. A 1:1 propensity score matching (PSM) analysis was used to balance the baseline data of patients. Independent risk factors associated with survival outcomes were screened by the least absolute shrinkage and selection operator and further determined by univariate and multivariate Cox proportional risk regression analyses. The overall survival (OS) of patients was evaluated by Kaplan–Meier analysis and compared with a log-rank test. The cumulative incidence function was used to estimate the 5-year probabilities of the cancer-specific mortality of PSC. A nomogram was constructed to illustrate the competing risk model to predict the 3- and 5-year OS, and corresponding concordance indexes (C-indexes) and calibration curves were used to assess and validate the competing risk nomogram. Results: A total of 2285 patients with PSC were included in this study. Compared with SCC and LAC patients, the Kaplan–Meier analysis showed that patients with PSC had a worse prognosis, with a median survival of 5 months (95% confidence interval [CI]: 5-6 months) and a 5-year OS rate of 15.3% (95% CI: 13.9%-16.9%). Similar outcomes were demonstrated after 1:1 PSM. Moreover, the competing risk model showed that age, T stage, M stage, tumor size, lymph node ratio (LNR), surgery, and chemotherapy were associated with PSC-specific mortality. The 5-year C-index of the nomogram was 0.718. Calibration curves illustrated that the nomogram was well-validated and had great accuracy. Conclusions: Patients with PSC had a worse survival outcome compared with SCC or LAC patients. Age, T stage, M stage, tumor size, LNR, surgery, and chemotherapy were associated with PSC-specific mortality. The competing risk nomogram displayed excellent discrimination in predicting PSC-specific mortality.

Pulmonary sarcomatoid carcinoma mimicking pleural mesothelioma: A case report

INTRODUCTION

Pulmonary sarcomatoid carcinoma (PSC) is an extremely rare biphasic tumor characterized by a mixture of malignant epithelial and mesenchymal cells. Owing to the rarity, as well as the lack of typical manifestations and imaging signs, the rate of misdiagnosis is high. Herein, we present a case of PSC misdiagnosed as pleural mesothelioma in a 59-year-old man.

PATIENT CONCERNS

A 59-year-old man presented with recurrent coughing, fever, and chest pain.

DIAGNOSIS

Chest computed tomography showed 2 large and dense masses involving the inferior lobes of right lung, along with slight irregular pleural thickening and a small amount of effusion.

INTERVENTIONS

Chest computed tomography-guided tumor biopsy was performed. PSC was confirmed based on histopathology and immunohistochemistry. The patient refused treatment due to economic reasons.

OUTCOMES

The patient developed adrenal, multiple lung and brain metastasis. The overall survival time was 11 months.

CONCLUSIONS

PSC, despite its rarity, should be considered in the differential diagnosis of lung cancer. Besides, biopsy, histopathology, and specific immunohistochemical staining of larger tissue specimens can be contributing to the accurate diagnosis of PSC.

Integrin-linked kinase pathway in heterogeneous pulmonary sarcomatoid carcinoma

Pulmonary sarcomatoid carcinoma (PSC) is classified as poorly differentiated, and non-small cell lung carcinomas that contained a component of sarcoma or sarcoma-like differentiation are rare. The underlying carcinogenetic mechanism governing PSC remains unclear. The current study investigated the underlying carcinogenetic mechanism of PSC based on the hypothesis that it involves the epithelial-mesenchymal transition (EMT) process. Mutation analysis of PSCs, including carcinosarcoma, pleomorphic carcinoma and epithelial carcinoma specimens, was performed using targeted deep sequencing, whole transcriptome analysis and digital spatial profiling (DSP). PSCs exhibit a distinct mutation profile, with TP53, SYNE1 and APC mutations. Therefore, clustering of the gene expression profiles allowed the PSCs to be distinguished from the epithelial carcinomas. Increased gene expression of fibronectin in PSC was an important contributor to differential profiles. Pathway analysis revealed enhanced activity of the integrin-linked kinase (ILK) signaling pathway in the PSCs. DSP analysis using 56 antibodies of marker proteins confirmed significantly higher expression of fibronectin in PSCs. Intratumor heterogeneity of fibronectin expression was observed in sarcoma components. In conclusion, epithelial-mesenchymal transition process mediated by ILK signaling may be associated with carcinogenetic mechanisms of PSC. Overexpression of fibronectin mediated by ILK signaling appears to serve a role in the EMT involved in the PSC transformation process.

Adjuvant chemotherapy for pulmonary sarcomatoid carcinoma: A retrospective analysis of the National Cancer Database

OBJECTIVES

Pulmonary sarcomatoid carcinoma (PSC) is a rarely occurring variant of non-small cell lung cancer with sarcoma-like features. Compared with traditional non-small cell lung cancer, PSC patients typically present later and have poorer prognoses, irrespective of stage. The standard of care is resection, but guidelines for the use of adjuvant chemotherapy have not been established. To advance the development of evidence-based management algorithms for PSC after resection, a statistical analysis on a nationwide representative sample of patients was performed.

METHODS

A retrospective cohort study was performed by querying the National Cancer Database for patients with a diagnosis of PSC between 2004 and 2015. Patients who received complete anatomical resection with or without adjuvant chemotherapy were included. Multivariable regression was used to detect factors associated with the receipt of adjuvant chemotherapy. Multivariable Cox regression of overall survival and Kaplan-Meier survival analysis on propensity-matched groups was conducted to study the association between adjuvant chemotherapy and prognosis.

RESULTS

We included 1497 patients with PSC in the final analysis. Factors associated with receiving adjuvant chemotherapy were age, histology, and receipt of adjuvant radiation. The results of multivariable Cox analysis and Kaplan-Meier analysis on propensity matched groups yielded similar trends: adjuvant chemotherapy was associated with improved 5-year overall survival for stage II and III disease, but not for stage I disease.

CONCLUSIONS

Multiple factors are associated with receipt of adjuvant chemotherapy for PSC, and this treatment appears to be associated with improved survival in stage II and stage III, but not stage I patients.

Additional chemotherapy improves survival in stage II-III pulmonary sarcomatoid carcinoma patients undergoing surgery: a propensity scoring matching analysis

Background

The role of additional chemotherapy in pulmonary sarcomatoid carcinoma (PSC) is controversial. This study aimed to investigate the function of chemotherapy in PSC patients with surgical resection.

Methods

PSC patient information between 2004 to 2016 was extracted from the Surveillance, Epidemiology, and End Results (SEER) database. X-tile software was used to calculate the optimal cut-off value to divide groups. The disease stages were recalculated according to the American Joint Commission on Cancer (AJCC) 8^th edition tumor-node-metastasis (TNM) staging system. Propensity score matching (PSM) analysis was conducted to balance the baseline of patients. Kaplan-Meier analysis and Cox proportional hazards analysis were used to evaluate survival outcome.

Results

A total of 865 PSC patients were included in our study. Among them, 611 patients were only operated with surgery, and the 254 others were treated with additional chemotherapy. The median age was 69.0 years (interquartile range, 61.6 to 76.3 years). Kaplan-Meier analysis showed that patients with additional chemotherapy had longer overall survival (OS) and cancer-specific survival (CSS, P<0.05). The median OS and the 1-, 3-, 5-year OS rates were 36.0 months (95% CI: 20.5–51.5 months), 72.7%, 49.6% and 38.5% in the chemotherapy group and 29.0 months (95% CI: 23.6–34.4 months), 63.2%, 44.5% and 37.6% in the non-chemotherapy group, respectively. The OS advantage of chemotherapy was not statistically significant after PSM analysis. Moreover, Cox proportional hazards model showed that chemotherapy was an independent prognosis factor for better OS and CSS. In subgroup of stages II and III, the chemotherapy group had a survival advantage (P<0.05). Patients with young age, female gender, low histology grade, large tumor size and lobectomy surgical resection benefited more from chemotherapy.

Conclusions

Chemotherapy is recommended for stages II and III PSC patients undergoing surgery, especially for those with young age, female gender, low histology grade, large tumor size and lobectomy surgical resection.

First-line albumin-bound paclitaxel/carboplatin plus apatinib in advanced pulmonary sarcomatoid carcinoma: A case series and review of the literature

RATIONALE

Pulmonary sarcomatoid carcinoma (PSC) is an uncommon type of non-small cell lung cancer, exhibiting aggressive behavior and resistance to the conventional chemoradiotherapy. To date, the optimal treatment for PSC has not been elucidated.

PATIENT CONCERNS

Three male patients including a 69-year-old smoker (Case 1), a 45-year-old non-smoker (Case 2), and a 69-year-old smoker (Case 3) were admitted because of cough, back pain, and loss of body weight respectively.

DIAGNOSES

Radiographical examinations in these patients showed bulky intrathoracic lesions, which were pathologically diagnosed as PSC staging III-IV by computed tomography-guided percutaneous biopsy and endoscopy.

INTERVENTIONS

Immunotherapy was not covered by their health insurance and they refused immune checkpoint inhibitors for financial reasons. In addition, a radical resection was not appropriate due to the advanced staging of these lesions. Therefore, first-line albumin-bound paclitaxel (nab-paclitaxel, 260 mg/m of the body surface area) and carboplatin (area under curve 5) combined with oral apatinib (425 mg, daily) were administered empirically.

OUTCOMES

Two patients achieved a partial response and the other case showed stable disease lasting for more than 6 months. However, 1 of them indicated progression on the 7-month follow up.

LESSONS

Nab-paclitaxel/carboplatin plus apatinib showed limited short-term efficacy in advanced, unresectable PSC. The rapid resistance of PSC to the current therapeutic regimen necessitates further researches, as more effective agents are urgently needed.

Dramatic Response of Pulmonary Sarcomatoid Carcinoma to Nivolumab Combined with Anlotinib: A Case Report

Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small-cell lung cancer, which is resistant to the conventional chemotherapy and radiotherapy with a poor prognosis. Limited case reports have showed good response to the immunotherapy in PSC patients with high PD-L1 expression generally. Herein, we report a case of rapid recurrence of PSC during postoperative adjuvant chemotherapy in a 62-year-old male ex-smoker. The patient had high PD-L1 expression (tumor proportion score: 90%) and KRAS exon 2 mutation. Nivolumab combined with anlotinib was administered synchronously. Clinical symptoms gradually relieved and response evaluation on imaging revealed a partial response after 8 weeks. This case suggests immunotherapy combined with antiangiogenic agent anlotinib may be a potential promising strategy to treat PSC patients.

Frequent Mutations of POT1 Distinguish Pulmonary Sarcomatoid Carcinoma From Other Lung Cancer Histologies

INTRODUCTION

Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small-cell lung cancer (NSCLC) harboring mutations in many canonical NSCLC-driver genes (eg, TP53, KRAS, MET). Protection of telomeres 1 (POT1) mutations are observed in angiosarcoma and chronic lymphocytic leukemia, but their frequency in other solid tumors, including NSCLC subtypes, has not been rigorously explored.

MATERIALS AND METHODS

We analyzed next-generation sequencing data from 62,368 tumors, including 11,134 NSCLCs and 100 PSCs. We performed logistic regression to identify associations between POT1 mutation frequency and tumor histology across 184 tumor categories, adjusting for tumor mutational burden. We further explored co-occurring gene mutations in genes previously reported to underlie PSC tumorigenesis.

RESULTS

Across 184 tumor categories, POT1 mutations were most frequent in PSC and were 14 times more common in PSC (28%) than in other tumor types (P = 1.23 × 10^-31) and 6.7 times more common in PSC than other NSCLCs (P = 5.1 × 10^-17). PSCs harboring KRAS mutations were significantly more likely to harbor POT1 mutations (P = 1.3 × 10^-3), whereas those with TP53 mutations were less likely to harbor POT1 mutations (P = .037). One-fourth of POT1-mutated PSCs harbored a second POT1 mutation. Across all PSCs, 83% of POT1 mutations were in the OB1/OB2 (DNA-binding) domain (P = 1.5 × 10^-5), an enrichment not observed in other tumor types.

CONCLUSION

We report an unanticipated association between POT1 mutation and PSC. Unlike other molecular alterations that are frequent across NSCLC subtypes, POT1 mutations are largely unique to PSC. This finding may help to develop disease-defining molecular subgroups within PSC and presents opportunities for molecularly stratified prognostication and therapy.

The diagnostic utility of zinc E-box 1 (ZEB1) transcription factor for identification of pulmonary sarcomatoid carcinoma in cytologic and surgical specimens

OBJECTIVE

Although uncommon, pulmonary sarcomatoid carcinoma carries a worse prognosis due to poor chemotherapeutic response. Currently, a histologic spindle and/or giant cell component indicates sarcomatoid differentiation, with zinc E-box binding homeobox 1 (ZEB1) implicated in promoting epithelial-mesenchymal transition. However, diagnostic use of ZEB1 in limited specimens, including cell block (CB) preparations, remains unclear.

MATERIALS AND METHODS

Pulmonary sarcomatoid (SARC, n = 15), typical (TC, n = 10) and atypical carcinoid (AC, n = 10), small cell (SCLC, n = 8) and large cell neuroendocrine carcinoma (LCNEC, n = 9), squamous cell carcinoma (SQ, n = 7), and adenocarcinoma (ADC, n = 7) CBs along with 69 SARCs, 20 TCs, 21 ACs, 9 SCLCs, 10 LCNECs, 71 SQs, 402 ADCs, 16 large cell carcinoma (LCC) and 17 other thoracic tumor (OT) surgical specimens between 2007 and 2018 were retrieved. ZEB1 (Sigma Aldrich, St. Louis, Mo and Novus Biological, Centennial, Colo) immunohistochemistry was graded 1+ to 3+, with ≥1+ and >5% staining considered positive.

RESULTS

Nuclear ZEB1 was seen in 80% SARC (12/15), 0% TC (0/10), 0% AC (0/10), 12.5% SCLC (1/8) and 11.1% LCNEC (1/9), 0% SQ (0/7), and 0% ADC (0/7) CBs. In surgical specimens, 75.4% SARCs (52/69), 0% TCs (0/20), 0% ACs (0/21), 11.1% SCLCs (1/9), 30% LCNECs (3/10), 0% SQs (0/71), 0.2% ADCs (1/402), 12.5% LCCs (2/16), and 11.8% OTs (2/17) demonstrated ZEB1. ZEB1 sensitivity and specificity in cytology and surgical specimens were 80% and 96.1%, and 75.4% and 98.1%, respectively.

CONCLUSIONS

ZEB1 is sensitive and highly specific for pulmonary sarcomatoid carcinoma in limited cytologic and surgical specimens. Diagnostic pitfalls include high-grade neuroendocrine tumors and large cell carcinoma, which are resolvable by morphologic considerations.

Gingival metastasis of a mediastinal pulmonary sarcomatoid carcinoma: a case report

BACKGROUND

Pulmonary sarcomatoid carcinoma (PSC) is a rare malignancy with both epithelial and sarcoma components, and high tumor metastasis potential.

CASE PRESENTATION

A 63-year-old male patient had a tumor in the right posterior mediastinum, and was eventually diagnosed with PSC and gingival metastasis. The patient underwent thoracoscopic right upper pneumonectomy with lymph node dissections, and the subsequent gingival biopsy revealed a metastatic PSC. The immunohistochemistry revealed that both PSC site tissues were positive for vimentin, CKAE1/AE3 and Ki-67. The patient received radiotherapy and chemotherapy after surgery, and deceased two months later due to systemic tumor metastases.

CONCLUSION

PSC metastasis is variable, and leads to diagnostic dilemma or erroneous diagnosis. A differential diagnosis can help to distinguish it from gingival cancer.