Sarcomatoid neoplasms of the lung and pleura

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.

Management of sarcomatoid Malignant pleural mesothelioma brain metastases with stereotactic radiosurgery: an Illustrative case

Background: Malignant pleural mesothelioma (MPM) is a rare cancer of the respiratory system that rarely metastasizes to the brain. We report a case of sarcomatoid MPM (SMPM) managed with Stereotactic radiosurgery (SRS) to achieve intracranial tumor control and improve neurological symptoms.Illustrative case: This 67-year-old female patient underwent SRS twice in order to treat a total of 15 brain metastases. One-month follow-up imaging after the first SRS demonstrated local tumor response and seven tumors with symptomatic vasogenic edema that responded to initial corticosteroids followed by bevacizumab. At a three-month follow-up after the first procedure, eight new tumors were detected and required repeat SRS. Although sustained tumor control resulted in improved neurological function, the patient subsequently expired from systemic disease progression 12 months after initial diagnosis and six months after initial SRS for brain metastases despite the concurrent use of systemic immunotherapy and systemic chemotherapy.Conclusions: Although SRS provided overall tumor control of metastatic brain disease, further advances in systemic therapies will be needed to improve survival in this aggressive rare cancer.

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.

Pulmonary blastoma treatment response to anti-PD-1 therapy: a rare case report and literature review

Pulmonary blastoma (PB) is a rare and invasive malignancy of the lungs with a poor prognosis. Although the mainstay treatment of PB is surgery, and radiotherapy and chemotherapy have been reported, no standard therapy exists for patients inoperable in advanced stages. Moreover, little is known about driver mutation status and immunotherapy efficacy. This paper presents a male patient diagnosed with classic biphasic PB using CT-guided lung biopsy pathology and immunohistochemistry. The patient's symptoms included cough, chest pain, shortness of breath, hemoptysis, and hypodynamia. The primary focus of this paper is to discuss the impact of anti-PD-1 immunotherapy on PB. The patient experienced progression-free survival (PFS) of over 27 months following sintilimab second-line anti-PD-1 therapy. The patient has currently survived for nearly 40 months with a satisfactory quality of life.

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.

Sulfated Glycans Recognized by S1 Monoclonal Antibody can Serve as a Diagnostic Marker for Malignant Pleural Mesothelioma

PURPOSE

Malignant pleural mesothelioma (MPM) is a malignant neoplasm of the pleura caused by asbestos exposure. For diagnosis of MPM, immunohistochemistry using multiple markers is recommended to rule out differential diagnoses, such as pulmonary adenocarcinoma. However, the specificity of currently used markers is not fully satisfactory. We previously developed a monoclonal antibody named S1, which recognizes 6-sulfo sialyl Lewis x, an L-selectin ligand expressed on high endothelial venules. During the screening process, we discovered that this antibody stained normal pleural mesothelium. This finding prompted us to hypothesize that the epitope recognized by S1 might serve as a new diagnostic marker for MPM.

METHODS

To test this hypothesis, we immunostained human MPM (n = 22) and lung adenocarcinoma (n = 25) tissues using S1 antibody.

RESULTS

77.3% of MPM were S1 positive, and if limited to epithelioid type, the positivity rate was 100%, while that of lung adenocarcinoma was only 36.0%. Statistical analysis revealed a significant difference in the S1 positivity rate between each disease. Furthermore, immunohistochemistry using a series of anti-carbohydrate antibodies combined with glycosidase digestion revealed the structure of sulfated glycans expressed in MPM to be 6-sulfo sialyl N-acetyllactosamine attached to core 2-branched O-glycans.

CONCLUSION

We propose that the S1 glycoepitope could serve as a new diagnostic marker for MPM.

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.

Durvalumab Plus Tremelimumab in Solid Tumors: A Systematic Review

INTRODUCTION

Cancer immunotherapy represents one of the most important innovations in modern medicine. Durvalumab is an anti-programmed cell death ligand 1 (PDL-1) agent which is currently under investigation in several studies in combination with the anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) drug tremelimumab. The aim of this review was to systematically identify and revise the current scientific literature investigating the combination of these two drugs in solid tumors.

METHODS

A digital search on the Medline (PubMed interface) and Scopus databases for articles published from inception to 26 February 2021 was performed. The terms used for the search were durvalumab AND tremelimumab. Trials reported in English involving adult patients with solid cancers treated with the combination durvalumab plus tremelimumab were retrieved; the references of the articles were cross-checked to identify missing papers.

RESULTS

The electronic search produced 267 results; after exclusion of duplicates, irrelevant articles, reviews, and papers not in English or missing data, 19 articles were included for revision. The total number of patients treated with the combination of durvalumab and tremelimumab in the studies retrieved was 2052.

CONCLUSION

The combination of durvalumab plus tremelimumab showed some oncological advantages in comparison with traditional chemotherapies in some subsets of tumors, but generally has not shown consistent advantages in comparison with the employment of durvalumab monotherapy. A number of the studies examined had intrinsic methodological limitations; therefore, future well-designed studies involving larger cohorts are warranted.

Sarcomatoid carcinoma associated with chronic empyema and early lung and pleural metastases: A case report

INTRODUCTION

The relationship between chronic empyema and malignant tumors, most of which are lymphoma, has been recognized for many decades. Sarcomatoid carcinoma associated with chronic empyema is extremely rare, may metastasize to other organs in the early stage, and rapidly progresses to death. As far as we know, this was the first case report on sarcomatoid carcinoma associated chronic empyema.

THE PATIENTS MAIN CONCERNS AND IMPORTANT CLINICAL FINDINGS

A 59-year-old man presented to our hospital with a 9-year history of chronic empyema and a chief complaint of left chest wall pain for 5 months. The diagnostic contrast-enhanced computed tomography (CT) showed a large irregular soft tissue mass located on the left lower hemithorax at the margin of the empyema cavity extending to the adjacent chest wall and lung parenchyma. In addition, CT revealed pleural and pulmonary metastases surrounded by ground glass opacity.

THE MAIN DIAGNOSIS, THERAPEUTICS INTERVENTIONS, AND OUTCOMES

The patient underwent CT guided percutaneous core needle biopsy (PCNB). The histopathological evaluation showed carcinomatous proliferation of pleomorphic spindle cells with extensive necrosis. Immunohistochemically, tumor cells were positive for cytokeratin and vimentin. The final histopathological diagnosis was sarcomatoid carcinoma underlying chronic empyema. The tumors showed rapid progression on serial simple radiography. Palliative treatments were performed, but the patient still developed severe dyspnea and died shortly after on day 16.

CONCLUSION

Sarcomatoid carcinoma can occur very rarely as a complication of chronic empyema, and is more aggressive than usual. Early detection of developing malignancy during the follow-up of chronic empyema is an important factor for patient prognosis.

Sarcomatoid carcinoma of the lung

Sarcomatoid carcinoma (SC) of the lung is a rare histological subtype of nonsmall cell lung cancer and comprises a diagnostically and therapeutically challenging group of tumors. We report a patient of SC of the lung in an elderly patient who presented with a lung mass. Computed tomography-guided biopsy of the lung mass was done, which clinched the diagnosis. We present this case because of the rarity of this histological subtype and to expand understanding regarding this rare cancer.

A Partial Response of Pulmonary Pleomorphic Carcinoma to Camrelizumab (PD1 Monoclonal Antibody) Monotherapy: A Case Report

We report a case of a 68-year-old man diagnosed with pulmonary pleomorphic carcinoma who showed partial response after a single treatment with camrelizumab (PD1 monoclonal antibody). The patient's tumor was positive for programmed cell death ligand 1 (PD-L1) and progressed rapidly after a course of chemotherapy. Fortunately, the tumors dramatically shrank after one cycle of camrelizumab, an anti-programmed cell death-1 (PD-1) antibody developed by Chinese Hengrui Medicine. In conclusion, camrelizumab may be a good treatment option, especially in tumors that express PD-L1.

Phase II study of durvalumab and tremelimumab in pulmonary sarcomatoid carcinoma: KCSG-LU16-07

BACKGROUND

Pulmonary sarcomatoid carcinoma (PSC) is rare with a poor outcome and is resistant to conventional cytotoxic chemotherapy. The efficacy and safety of durvalumab and tremelimumab for treating recurrent or metastatic PSCs were assessed by a nonrandomized, open-label, phase II study.

METHODS

A total of 18 patients with recurrent or metastatic PSC received 1500 mg of durvalumab and 75 mg of tremelimumab every four weeks, followed by 750 mg of durvalumab every two weeks until the disease progressed, or an unacceptable toxicity level was reached. The primary endpoint was the objective response rate (ORR). The secondary endpoints were progression-free survival (PFS), overall survival (OS), and toxicity. Genomic profiling of PSC by next-generation sequencing (NGS) and determination of peripheral blood lymphocyte subsets using flow cytometry were performed for exploratory analysis.

RESULTS

A total of 15 out of 18 patients were evaluated for the analysis of the primary endpoint. At the data cutoff point, the ORR of 26.7% (95% confidence interval [CI]: 7.8-55.1) was achieved with the median follow-up duration of 12.0 months (range, 8.4-16.1). Median PFS and OS were 5.9 months (95% CI: 1.1-11.9) and 15.4 months (95% CI: 11.1-not reached), respectively. Treatment-related adverse events (AEs) of any grade were reported in 16 patients; the most common AEs were pruritus (n = 5), pneumonitis (n = 4), and rash (n = 4). Treatment was discontinued in two patients due to AEs of grade ≥ 3.

CONCLUSIONS

Durvalumab and tremelimumab demonstrated clinical benefit with a prolonged survival and manageable toxicity profile in patients with recurrent or metastatic PSC.

New vistas in malignant mesothelioma: MicroRNA architecture and NRF2/MAPK signal transduction

Malignant mesothelioma (MM) is a cancer of the mesothelial lining of the pleura, peritoneum, pericardium and testes. The most common form is asbestos-linked MM that is etiologically linked to repeated asbestos exposure with a long latency period, although non-asbestos MM has also been reported. Late diagnosis, poor survival rates, lack of diagnostic and prognostic markers act as major impediments in the clinical management of MM. Despite advances in immune checkpoint inhibition and CAR T-cell-based therapies, MM which is of different histologic subtypes remains challenging to treat. We review microRNAs (miRNAs) and the miRNA interactome implicated in MM which can be useful as circulating miRNA biomarkers for early diagnosis of MM and as biomarkers for prognostication in MM. Further, we underscore the relevance of the NRF2/MAPK signal transduction pathway that has been implicated in MM which may be useful as druggable targets or as biomarkers of predictive response. In addition, since MM is driven partly by inflammation, we elucidate chemopreventive phytochemicals that are beneficial in MM, either via crosstalk with the NRF2/MAPK pathway or via concerted anticancer mechanisms, and may be of benefit as adjuvants in chemotherapy. Taken together, a multifactorial approach comprising identification of miRNA target hubs and NRF2/MAPK biomarkers along with appropriately designed clinical trials may enable early detection and faster intervention in MM translating into better patient outcomes for this aggressive cancer.

Update on the pathologic diagnosis of malignant mesothelioma

Malignant mesothelioma is an uncommon tumor that may be difficult to diagnose. The International Mesothelioma Interest Group has been writing guidelines for pathological diagnosis that are periodically updated. The guidelines are being updated based on published literature in the last 3 years, and experience of more than 20 leading international pathologists in the field who will be co-authors. Updates were discussed by attendees of the Pulmonary Pathology Society Biennial Meeting (Dubrovnik, Croatia, June 2019). Areas with significant advancements/changes include utilization of immunohistochemistry (establishing mesothelial lineage and benign versus malignant), prognosis and nuclear grading, biphasic malignant mesothelioma, transitional pattern, malignant mesothelioma in situ, and therapeutic/molecular targets.

Essentials for Pathological Evaluation of Peritoneal Surface Malignancies and Synoptic Reporting of Cytoreductive Surgery Specimens-A review and evidence-based guide

Peritoneal surface oncology has emerged as a subspecialty of surgical oncology, with the growing popularity of surgical treatment of peritoneal metastases comprising of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Pathological evaluation plays a key role in multidisciplinary management but there are still many areas where there are no guidelines or consensus on reporting. Some tumors presenting to a peritoneal surface oncology unit are rare and pathologists my not be familiar with diagnosing and classifying those. In this manuscript, we have reviewed the evidence regarding various aspects of histopathological evaluation of peritoneal tumors. It includes establishing a diagnosis, appropriate classification and staging of common and rare tumors and evaluation of pathological response to chemotherapy. In many instances, the information captured is of prognostic value alone with no direct therapeutic implications. But proper capturing of such information is vital for generating evidence that will guide future treatment trends and research. There are no guidelines/data set for reporting cytoreductive surgery specimens. Based on the authors' experience, a format for handling/grossing and synoptic reporting of these specimens is provided.

Prognostic factors for sarcomatoid carcinomas of lung: A single-centre experience

Background:

Although lung sarcomatoid carcinomas (LSCa) arised from the epithelial tissue, they have very distinctive features than other non-small cell lung carcinomas in terms of histopathology and survival. It constitutes 0.1%–0.4% of all lung cancers. The aim of our study is to evaluate the survival analysis of LSCa in a single thoracic surgery clinic and to determine the prognostic factors.

Materials and Methods:

It was a retrospective cohort study. After the approval of the local ethics committee, a total of 34 patients who were operated in our department between January 2010 and December 2018, whose pathologies were reported as sarcomatoid carcinoma was included in the study. The patients were analyzed by age, gender, presence of necrosis in the histopathological examination, tumor stage, tumor diameter, and tumor location.

Results:

There were 28 males and 6 females. The median age was 60 years (range: 36–80 years). The median survival was 42 months (32.6–52.2 months), and the 5-year overall survival was 33.6%. Significantly negative prognostic factors were tumor diameter and tumor stage (P = 0.003 and 0.001, respectively). Median disease-free interval (DFI) was 38 months (27.3–49.1 months), and 5-year DFI was 32.6%.

Conclusion:

LSCa are highly heterogeneous epithelial malignancies, and it has worse survival than other epithelial cancers. Relatively, satisfactory results can be obtained in these tumors with surgical treatment.

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.

Pulmonary Carcinosarcoma: A Case Report of Biphasic Lung Tumor

Pulmonary carcinosarcoma is an unusual biphasic tumor of the lung with carcinomatous and sarcomatous components. We report a case in a 71-year-old female who presented with a 13-cm lung mass. Microscopic examination revealed squamous cell carcinoma and chondrosarcoma with focal spindle cell atypia. In the most recent version of the World Health Organization (WHO) classification, carcinosarcoma is included in the category of sarcomatous neoplasms with a poorer prognosis than non-small cell lung carcinoma.

The Diagnosis of Pleural Tumors Other Than Mesothelioma

CONTEXT

- Pleural pathology has been dominated by discussions relating to the diagnosis, prognosis, etiology, and management of malignant mesothelioma. However, there exists a diverse group of other neoplasms that involve the pleura; the most common by far is metastatic carcinoma, usually of pulmonary origin. Other metastatic tumors of varied histogenesis do occur but are less common. Primary pleural neoplasms other than diffuse malignant mesothelioma are either uncommon or rare and have received less attention.

OBJECTIVE

- To provide a review of those diverse tumors that can involve the pleura other than mesothelioma in order to facilitate their accurate diagnosis.

DATA SOURCES

- Review of relevant literature published via PubMed and other search engines.

CONCLUSIONS

- A wide variety of tumors can involve the pleura. In most cases, the approach of considering the morphologic features with appropriate immunohistochemistry, in the correct clinical context, allows for a confident diagnosis. For a number of those soft tissue tumors that are well recognized in the pleura, such as solitary fibrous tumor, desmoid-type fibromatosis, synovial sarcoma, and epithelioid hemangioendothelioma, novel markers now exist based on an understanding of the individual tumors' molecular characteristics. Primary pleural lymphomas are rare with poor prognosis. They represent localized specific diffuse large B-cell lymphomas, with either post-germinal center B-cell or plasma cell lineage, arising in the context of either immunodeficiency or immune sequestration and with viral infection.

CDKN2A copy number and p16 expression in malignant pleural mesothelioma in relation to asbestos exposure

Background

Deletion of the CDKN2A locus is centrally involved in the development of several malignancies. In malignant pleural mesothelioma (MPM), it is one of the most frequently reported genomic alteration. MPM is strongly associated with a patients’ asbestos exposure. However, the status of CDKN2A and the expression of the corresponding protein, p16, in relation to MPM patient’s asbestos exposure is poorly known. Copy number alterations in 2p16, 9q33.1 and 19p13 have earlier been shown to accumulate in lung cancer in relation to asbestos exposure but their status in MPM is unclear.

Methods

We studied DNA copy numbers for CDKN2A using fluorescence in situ hybridization (FISH) and p16 expression by immunohistochemistry (IHC) in 92 MPM patients, 75 of which with known asbestos exposure status. We also studied, in MPM, copy number alterations in 2p16, 9q33.1 and 19p13 by FISH.

Results

We were unable to detect an association between p16 expression and pulmonary asbestos fiber count in MPM tumor cells. However, significantly more MPM patients with high pulmonary asbestos fiber count (> 1 million fibers per gram [f/g]) had stromal p16 immunoreactivity than MPM of patients with low exposure (≤ 0.5 million f/g) (51.4% vs 16.7%; p = 0.035, Chi-Square). We found that an abnormal copy number of CDKN2A in MPM tumor cells associated with a high pulmonary asbestos fiber count (p = 0.044, Fisher’s Exact test, two-tailed). In contrast to our earlier findings in asbestos associated lung cancer, DNA copy number changes in 2p16, 9q33 and 19p13 were not frequent in MPM although single cases with variable copy numbers on those regions were seen.

Conclusions

We found two instances where the gene locus CDKN2A or its corresponding protein expression, is associated with high asbestos exposure levels. This suggests that there may be biological differences between the mesotheliomas with high pulmonary asbestos fiber count and those with low fiber count.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5652-y) contains supplementary material, which is available to authorized users.

Mutation landscape and tumor mutation burden analysis of Chinese patients with pulmonary sarcomatoid carcinomas

INTRODUCTION

Pulmonary sarcomatoid carcinoma (PSC) is a group of rare tumors with the presence of both cancerous and sarcoma components in tumor. In this study, we explore their cancer genomic background and the relationship with clinical prognosis.

MATERIALS AND METHODS

A cohort of 32 PSC patients were retrospectively collected from the First People's Hospital of Changzhou between 2005 and 2016. Targeted next-generation sequencing (NGS) of 416 cancer-relevant genes was performed on 32 PSC tumors.

RESULTS

EGFR (28%), KRAS (22%), and MET (16%) are the most commonly mutated oncogenes, while the top mutated tumor suppressor genes are TP53 (69%) and RB1 (25%). The majority of EGFR mutations are rare mutations, some of which have not been reported before. Moreover, 4 out of 6 MET alterations are exon 14 skipping, far more frequent than in NSCLC. Interestingly, ARID1A was found to be co-mutated with TP53 at all times. The tumor mutation burden (TMB) is ranging from 3.3 to 52.2 per megabase (MB) with a median of 11.7 per MB and 13 patients have more than 20 mutations per MB. Patients mutated in BRCA2, KMT2B, SMARCA4 or TSC2 have significantly higher TMB compared to patients with wide-type genes.

CONCLUSION

Our study characterizes the genetic background of Chinese PSC patients and demonstrates the importance of involving EGFR rare mutations and MET exon 14 skipping targeted therapies into clinical trials for treating PSC patients. High TMB are seen in about 40.6% Chinese patients with PSC, which could benefit from immune checkpoint inhibitors.

Role of cytokines in combinatorial immunotherapeutics of non-small cell lung cancer through systems perspective

Lung cancer is the leading cause of deaths related to cancer and accounts for more than a million deaths per year. Various new strategies have been developed and adapted for treatment; still the survival for 5 years is just 16% in patients with non‐small cell lung cancer (NSCLC). Most of these strategies to combat NSCLC whether it is a drug molecule or immunotherapy/vaccine candidate require a big cost and time. Integration of computational modeling with systems biology has opened new avenues for understanding complex cancer biology. Resolving the complex interactions of various pathways and their crosstalk leading to oncogenic changes could identify new therapeutic targets with lesser cost and time. Herein, this review provides an overview of various aspects of NSCLC along with available strategies for its cure concluding with our insight into how systems approach could serve as a therapeutic intervention dissecting the immunologic parameters and cross talk between various pathways involved.

Best Practices Recommendations for Diagnostic Immunohistochemistry in Lung Cancer

Since the 2015 WHO classification was introduced into clinical practice, immunohistochemistry (IHC) has figured prominently in lung cancer diagnosis. In addition to distinction of small cell versus non-small cell carcinoma, patients' treatment of choice is directly linked to histologic subtypes of non-small cell carcinoma, which pertains to IHC results, particularly for poorly differentiated tumors. The use of IHC has improved diagnostic accuracy in the classification of lung carcinoma, but the interpretation of IHC results remains challenging in some instances. Also, pathologists must be aware of many interpretation pitfalls, and the use of IHC should be efficient to spare the tissue for molecular testing. The International Association for the Study of Lung Cancer Pathology Committee received questions on practical application and interpretation of IHC in lung cancer diagnosis. After discussions in several International Association for the Study of Lung Cancer Pathology Committee meetings, the issues and caveats were summarized in terms of 11 key questions covering common and important diagnostic situations in a daily clinical practice with some relevant challenging queries. The questions cover topics such as the best IHC markers for distinguishing NSCLC subtypes, differences in thyroid transcription factor 1 clones, and the utility of IHC in diagnosing uncommon subtypes of lung cancer and distinguishing primary from metastatic tumors. This article provides answers and explanations for the key questions about the use of IHC in diagnosis of lung carcinoma, representing viewpoints of experts in thoracic pathology that should assist the community in the appropriate use of IHC in diagnostic pathology.

Factors influencing malignant mesothelioma survival: a retrospective review of the National Mesothelioma Virtual Bank cohort

Background: Malignant mesothelioma (MM) is a rare but deadly malignancy with about 3,000 new cases being diagnosed each year in the US.  Very few studies have been performed to analyze factors associated with mesothelioma survival, especially for peritoneal presentation. The overarching aim of this study is to examine survival of the cohort of patients with malignant mesothelioma enrolled in the National Mesothelioma Virtual Bank (NMVB).   Methods:  888 cases of pleural and peritoneal mesothelioma cases were selected from the NMVB database, which houses data and associated biospecimens for over 1400 cases that were diagnosed from 1990 to 2017. Kaplan Meier's method was performed for survival analysis. The association between prognostic factors and survival was estimated using Cox Hazard Regression method and using R software for analysis. Results: The median overall survival (OS) rate of all MM patients, including pleural and peritoneal mesothelioma cases is 15 months (14 months for pleural and 31 months for peritoneal).  Significant prognostic factors associated with improved survival of malignant mesothelioma cases in this NMVB cohort were younger than 45, female gender, epithelioid histological subtype, stage I, peritoneal occurrence, and having combination treatment of surgical therapy with chemotherapy. Combined surgical and chemotherapy treatment was associated with improved survival of 23 months in comparison to single line therapies. Conclusions: There has not been improvement in the overall survival for patients with malignant mesothelioma over many years with current available treatment options. Our findings show that combined surgical and chemotherapy treatment in peritoneal mesothelioma is associated with improved survival compared to local therapy alone.

Factors influencing malignant mesothelioma survival: a retrospective review of the National Mesothelioma Virtual Bank cohort

Background: Malignant mesothelioma (MM) is a rare but deadly malignancy with about 3,000 new cases being diagnosed each year in the US.  Very few studies have been performed to analyze factors associated with mesothelioma survival, especially for peritoneal presentation. The overarching aim of this study is to examine survival of the cohort of patients with malignant mesothelioma enrolled in the National Mesothelioma Virtual Bank (NMVB).   Methods:  888 cases of pleural and peritoneal mesothelioma cases were selected from the NMVB database, which houses data and associated biospecimens for over 1400 cases that were diagnosed from 1990 to 2017. Kaplan Meier's method was performed for survival analysis. The association between prognostic factors and survival was estimated using Cox Hazard Regression method and using R software for analysis. Results: The median overall survival (OS) rate of all MM patients, including pleural and peritoneal mesothelioma cases is 15 months (14 months for pleural and 31 months for peritoneal).  Significant prognostic factors associated with improved survival of malignant mesothelioma cases in this NMVB cohort were younger than 45, female gender, epithelioid histological subtype, stage I, peritoneal occurrence, and having combination treatment of surgical therapy with chemotherapy. Combined surgical and chemotherapy treatment was associated with improved survival of 23 months in comparison to single line therapies. Conclusions: There has not been improvement in the overall survival for patients with malignant mesothelioma over many years with current available treatment options. Our findings show that combined surgical and chemotherapy treatment in peritoneal mesothelioma is associated with improved survival compared to local therapy alone.

Factors influencing malignant mesothelioma survival: a retrospective review of the National Mesothelioma Virtual Bank cohort

Background: Malignant mesothelioma (MM) is a rare but deadly malignancy with about 3,000 new cases being diagnosed each year in the US.  Very few studies have been performed to analyze factors associated with mesothelioma survival, especially for peritoneal presentation. The overarching aim of this study is to examine survival of the cohort of patients with malignant mesothelioma enrolled in the National Mesothelioma Virtual Bank (NMVB).  

Methods:  888 cases of pleural and peritoneal mesothelioma cases were selected from the NMVB database, which houses data and associated biospecimens for over 1400 cases that were diagnosed from 1990 to 2017. Kaplan Meier’s method was performed for survival analysis. The association between prognostic factors and survival was estimated using Cox Hazard Regression method and using R software for analysis.

Results: The median overall survival (OS) rate of all MM patients, including pleural and peritoneal mesothelioma cases is 15 months (14 months for pleural and 31 months for peritoneal).  Significant prognostic factors associated with improved survival of malignant mesothelioma cases in this NMVB cohort were younger than 45, female gender, epithelioid histological subtype, stage I, peritoneal occurrence, and having combination treatment of surgical therapy with chemotherapy. Combined surgical and chemotherapy treatment was associated with improved survival of 23 months in comparison to single line therapies.

Conclusions: There has not been improvement in the overall survival for patients with malignant mesothelioma over many years with current available treatment options. Our findings show that combined surgical and chemotherapy treatment in peritoneal mesothelioma is associated with improved survival compared to local therapy alone.

Clinicopathological characteristics and prognosis of pulmonary pleomorphic carcinoma: a population-based retrospective study using SEER data

Background

Pulmonary pleomorphic carcinoma (PPC) is a rare malignancy; unique clinicopathological characteristics and prognosis have not been described.

Methods

PPC patient information collected in the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2014 were extracted, evaluated, and compared with NSCLC patient data. Overall survival (OS) was evaluated by the Kaplan-Meier method. Univariate analysis (UVA) and multivariate analysis (MVA) by the Cox proportional hazards regression identified risk factors that predicted OS and the results were used to construct a nomogram to predict 1-, 3-, and 5-year OS in PPC patients.

Results

A total of 309 patients diagnosed with PPC were identified among the records of 320,510 NSCLC patients. The median age was 66 (IQR, 57-75) years, 59.2% were men, 79.3% were White, 63.9% had upper lobe tumors, 77.0% were poorly differentiated, and 38.0% were AJCC stage IV. Median OS was 9 (95% CI: 6.69-11.31) months and 5-year OS was 25.1% (95% CI: 23.6-26.6%). PPC patients had significantly larger and less differentiated tumors, a higher rate of radical surgical resection, less N+ disease, and fewer distant metastases (P<0.001) than NSCLC patients. UVA and MVA identified age, T stage, M stage, surgery, and chemotherapy as independent risk factors. The nomogram had a calibration index of 0.798.

Conclusions

PPC had distinct clinicopathological characteristics. Age, T stage, M stage, surgery and chemotherapy were independently associated with OS. The nomogram accurately predicted 1-, 3- and 5-year OS.

Ensuring the Safety and Security of Frozen Lung Cancer Tissue Collections through the Encapsulation of Dried DNA

Collected specimens for research purposes may or may not be made available depending on their scarcity and/or on the project needs. Their protection against degradation or in the event of an incident is pivotal. Duplication and storage on a different site is the best way to assure their sustainability. The conservation of samples at room temperature (RT) by duplication can facilitate their protection. We describe a security system for the collection of non-small cell lung cancers (NSCLC) stored in the biobank of the Nice Hospital Center, France, by duplication and conservation of lyophilized (dried), encapsulated DNA kept at RT. Therefore, three frozen tissue collections from non-smoking, early stage and sarcomatoid carcinoma NSCLC patients were selected for this study. DNA was extracted, lyophilized and encapsulated at RT under anoxic conditions using the DNAshell technology. In total, 1974 samples from 987 patients were encapsulated. Six and two capsules from each sample were stored in the biobanks of the Nice and Grenoble (France) Hospitals, respectively. In conclusion, DNA maintained at RT allows for the conservation, duplication and durability of collections of interest stored in biobanks. This is a low-cost and safe technology that requires a limited amount of space and has a low environmental impact.

Classification and Pathology of Lung Cancer

Advancement in the understanding of lung tumor biology enables continued refinement of lung cancer classification, reflected in the recently introduced 2015 World Health Organization classification of lung cancer. In small biopsy or cytology specimens, special emphasis is placed on separating adenocarcinomas from the other lung cancers to effectively select tumors for targeted molecular testing. In resection specimens, adenocarcinomas are further classified based on architectural pattern to delineate tissue types of prognostic significance. Neuroendocrine tumors are divided into typical carcinoid, atypical carcinoid, small cell carcinoma, and large cell neuroendocrine carcinoma based on a combination of features, especially tumor cell proliferation rate.

Recurrent Severe Hypoinsulinemic Hypoglycemia Responsive to Temozolomide and Bevacizumab in a Patient With Doege-Potter Syndrome

Nonislet cell tumor hypoglycemia is rare. We highlight the diagnosis and treatment of recurrent severe hypoglycemia in a 49-year-old woman with malignant solitary fibrous tumor of the pleura (Doege-Potter syndrome). The clinical, laboratory and radiologic findings of the case are presented and a brief literature review is provided. Of note, imaging studies showed a large mass in the right hemithorax and pathology and immunehistochemical stains confirmed a malignant solitary fibrous tumor of the pleura. She was a poor surgical candidate owing to a large tumor burden. She was treated with a combination of temozolomide and bevacizumab to which she responded with resolution of hypoglycemia. The treatment of choice for hypoglycemia in patients with the Doege-Potter syndrome is surgical excision. We here report that a combination of temozolomide and bevacizumab may be a viable option in patients with inoperable disease.

Recent Advances in the Diagnosis of Malignant Mesothelioma: Focus on Approach in Challenging Cases and in Limited Tissue and Cytologic Samples

Mesothelial proliferations can be diagnostically challenging in small specimens, such as body fluid cytology and small tissue biopsies. A great morphologic challenge for pathologists is the separation of benign reactive mesothelial proliferations from malignant mesotheliomas. Reactive mesothelial proliferations may have histologic features that resemble malignancy including increased cellularity, cytologic atypia, and mitoses. Recent advances in mesothelioma genetics resulted in identification of BAP1 mutations and p16 deletions as features of malignant mesotheliomas. Hence, BAP1 immunohistochemistry and fluorescence in situ hybridization for p16 emerged as 2 most common diagnostically helpful ancillary studies used on limited samples when the question is whether the proliferation is malignant or benign. In contrast, separation of mesothelioma from other malignancies is relatively straight forward using morphology and immunohistochemical stains. The choice of antibody panel to be applied in an individual case is driven by morphology, either epithelioid or sarcomatoid. This brief review will focus on morphology and ancillary testing of mainly pleural mesothelial proliferations.

Sarcomatoid carcinoma of the lung: a rare histological subtype of non-small cell lung cancer with a poor prognosis even at earlier tumour stages

Objectives

Pulmonary sarcomatoid carcinoma (PSC) is a rare histological subtype of non-small cell lung cancer and comprises a diagnostically and therapeutically challenging group of tumours. We explored the clinicopathological features and prognostic factors of this tumour.

Methods

We conducted a retrospective study of all patients who were treated for PSC in the Department of Thoracic Surgery between May 2005 and December 2014. Primary outcomes of interest were patient survival and prognostic factors.

Results

A total of 58 patients were treated for sarcomatoid carcinoma within the described period and 46 patients underwent surgical resection with curative intent. The mean follow-up period was 30 months. Of the operated patients, 21.7% had pathological stage I disease, and 78.3% had more advanced disease. There were 25 carcinosarcomas, 10 pleomorphic carcinomas, 7 spindle cell carcinomas, 3 giant cell carcinomas and 1 pulmonary blastoma. Overall 5-year survival of the operated patients was 28.7%. A total of 28 patients experienced recurrence and died cancer-related. Our analysis revealed that tumour size, gender, histological entity, lymphatic vessel invasion (L1) and vascular invasion (V1) did not influence survival. There was a trend for decreased survival in older patients (>65 years).

Conclusions

Surgical treatment can achieve satisfactory results with low perioperative mortality, but the overall prognosis even with multimodality concepts and in earlier tumour stages is worse compared to other types of non-small cell lung cancer.

Guidelines for Pathologic Diagnosis of Malignant Mesothelioma 2017 Update of the Consensus Statement From the International Mesothelioma Interest Group

CONTEXT

- Malignant mesothelioma (MM) is an uncommon tumor that can be difficult to diagnose.

OBJECTIVE

- To provide updated, practical guidelines for the pathologic diagnosis of MM.

DATA SOURCES

- Pathologists involved in the International Mesothelioma Interest Group and others with an interest and expertise in the field contributed to this update. Reference material included up-to-date, peer-reviewed publications and textbooks.

CONCLUSIONS

- There was discussion and consensus opinion regarding guidelines for (1) distinguishing benign from malignant mesothelial proliferations (both epithelioid and spindle cell lesions), (2) cytologic diagnosis of MM, (3) recognition of the key histologic features of pleural and peritoneal MM, (4) use of histochemical and immunohistochemical stains in the diagnosis and differential diagnosis of MM, (5) differentiating epithelioid MM from various carcinomas (lung, breast, ovarian, and colonic adenocarcinomas, and squamous cell and renal cell carcinomas), (6) diagnosis of sarcomatoid MM, (7) use of molecular markers in the diagnosis of MM, (8) electron microscopy in the diagnosis of MM, and (9) some caveats and pitfalls in the diagnosis of MM. Immunohistochemical panels are integral to the diagnosis of MM, but the exact makeup of panels employed is dependent on the differential diagnosis and on the antibodies available in a given laboratory. Depending on the morphology, immunohistochemical panels should contain both positive and negative markers for mesothelial differentiation and for lesions considered in the differential diagnosis. Immunohistochemical markers should have either sensitivity or specificity greater than 80% for the lesions in question. Interpretation of positivity generally should take into account the localization of the stain (eg, nuclear versus cytoplasmic) and the percentage of cells staining (>10% is suggested for cytoplasmic and membranous markers). Selected molecular markers are now being used to distinguish benign from malignant mesothelial proliferations. These guidelines are meant to be a practical diagnostic reference for the pathologist; however, some new pathologic predictors of prognosis and response to therapy are also included.

A Rare Case of Sarcomatoid Carcinoma of the Lung with Spine Metastasis, Including a Literature Review

BACKGROUND Sarcomatoid carcinoma is a rare, aggressive, malignant cancer composed of sarcoma and sarcoma-like components, and can occur in different organs such as the thyroid gland, bone, skin, breast, pancreas, liver, urinary tract, and lung. Pulmonary sarcomatoid carcinoma accounts for only a small percentage of lung cancers and has histological variants that include pleomorphic carcinoma, giant cell carcinoma, spindle cell carcinoma, carcinosarcoma, and pulmonary blastoma. CASE REPORT Here, we present a case of sarcomatoid carcinoma in a 63-year-old HIV-positive Hispanic male who presented with back pain, dry cough, and weight loss. A CT scan of his chest showed an ovoid mass in the lower lobe of the left lung, and an MRI of the spine showed a left lateral paraspinal soft tissue mass causing central canal stenosis and mild cord compression. The patient underwent laminectomy and resection of the spinal mass. A transthoracic needle biopsy of the lung and spinal masses had similar histopathology, and were indicative of sarcomatoid carcinoma. CONCLUSIONS We report a rare case of sarcomatoid carcinoma involving both the lung and spinal cord in the same patient. Sarcomatoid carcinomas of the lung have poor prognosis and are aggressive cancers. Moreover, our case also had the co-occurrence of HIV and sarcomatoid carcinoma.

Pulmonary Sarcomatoid Carcinoma: An Analysis of the National Cancer Data Base

INTRODUCTION

Pulmonary sarcomatoid carcinoma (PSC) is a grouping of 5 rare non-small-cell lung cancer (NSCLC) subtypes. We studied the clinical characteristics and outcomes of PSC utilizing the National Cancer Data Base (NCDB), an oncology outcomes database.

METHODS

The NCDB lung cancer database was queried from 1998 to 2011 for PSC using ICD-O-3 codes. Data were extracted for patient demographics, tumor pathology, treatment, and outcomes. Overall survival (OS) data were available for patients diagnosed from 1998 to 2006 and comorbidity data from 2003 to 2011. Univariate association with covariates between PSC and other forms of NSCLC was assessed by the chi-square test or ANOVA, as appropriate.

RESULTS

Of the 1,547,531 NSCLC patients in the NCDB from 1998 to 2011, 7965 were identified with PSC (0.5%). PSC patients had a median age of 70 years, 59% were men, and 89% were white. At presentation, 18% had American Joint Committee on Cancer stage I disease, 10% stage II, 24% stage III, and 48% stage IV. The median OS for stage I-II PSC was 16.9 months, 5.8 months for stage III, and 5.4 months for stage IV. There was a higher risk of death on multivariate analysis for PSC patients compared to other histologic subtypes of NSCLC in all patients (hazard ratio = 1.34 (95% confidence interval, 1.20-1.48) P < .001) and in propensity score-matched subsets (hazard ratio = 1.34; 95% confidence interval, 1.15-1.56; P < .001).

CONCLUSION

PSC is a rare histologic subtype of NSCLC, accounting for 0.5% of all lung cancers. The disease of patients with PSC has aggressive clinical characteristics and an inferior survival outcome relative to other histologic subtypes of NSCLC.

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.

The Potential Malignancy of a Solitary Fibrous Tumour of the Lung

Solitary fibrous tumours (SFTs) are rare neoplasms that in the majority of cases are benign. We present the case of a 52-year-old male, with a 23-year history of a slow growing pleural mass, presenting to our department with worsening dyspnoea and localised chest discomfort. The purpose of this case report is to highlight the potential malignancy of a solitary fibrous tumour of the lung along with the key features in diagnosis and management.

[Pulmonary sarcomatoid carcinoma]

Pulmonary sarcomatoid carcinomas are a rare group of tumors accounting for about one percent of non-small cell lung carcinoma (NSCLC). In 2015, the World Health Organization classification united under this name all the carcinomas with sarcomatous-like component with spindle cell or giant cell appearance, or associated with a sarcomatous component sometimes heterologous. There are five subtypes: pleomorphic carcinoma, spindle cell carcinoma, giant cell carcinoma, carcinosarcoma and pulmonary blastoma. Clinical characteristics are not specific from the other subtypes of NSCLC. Epithelial to mesenchymal transition pathway may play a key role. Patients, usually tobacco smokers, are frequently symptomatic. Tumors are voluminous more often peripherical than central, with strong fixation on FDG TEP CT. Distant metastases are frequent with atypical visceral locations. These tumors have poorer prognosis than the other NSCLC subtypes because of great aggressivity, and frequent chemoresistance. Here we present pathological description and a review of literature with molecular features in order to better describe these tumors and perhaps introduce new therapeutics.

BAP1 (BRCA1-associated protein 1) is a highly specific marker for differentiating mesothelioma from reactive mesothelial proliferations

The distinction between malignant mesothelioma and reactive mesothelial proliferation can be challenging both on histology and cytology. Recently, variants of the BRCA1-associated protein 1 (BAP1) gene resulting in nuclear protein loss were reported in hereditary and sporadic mesothelioma. Using immunohistochemistry, we evaluated the utility of BAP1 expression in the differential diagnosis between mesothelioma and other mesothelial proliferations on a large series of biopsies that included 212 mesotheliomas, 12 benign mesothelial tumors, and 42 reactive mesothelial proliferations. BAP1 stain was also performed in 70 cytological samples (45 mesotheliomas and 25 reactive mesothelial proliferations). BAP1 was expressed in all benign mesothelial tumors, whereas 139/212 (66%) mesotheliomas were BAP1 negative, especially in epithelioid/biphasic compared with sarcomatoid/desmoplastic subtypes (69% vs 15%). BAP1 loss was homogeneous in neoplastic cells except for two epithelioid mesotheliomas showing tumor heterogeneity. By fluorescence in situ hybridization, BAP1 protein loss was paralleled by homozygous deletion of the BAP1 locus in the vast majority of BAP1-negative tumors (31/41, 76%), whereas 9/10 BAP1-positive mesotheliomas were normal. In biopsies interpreted as reactive mesothelial proliferation BAP1 loss was 100% predictive of malignancy, as all 6 cases subsequently developed BAP1-negative mesothelioma, whereas only 3/36 (8%) BAP1-positive cases progressed to mesothelioma. On cytology/cell blocks, benign mesothelial cells were invariably positive for BAP1, whereas 64% of mesotheliomas showed loss of protein; all 6 cases showing BAP1 negativity were associated with histological diagnosis of BAP1-negative mesothelioma. BAP1 stain also showed utility in the differential of mesothelioma from most common pleural and peritoneal mimickers, such as lung and ovary carcinomas, with specificity and sensitivity of 99/70% and 100/70%, respectively. Our results show that BAP1 protein is frequently lost in mesothelioma, especially of epithelioid/biphasic subtype and is commonly associated with homozygous BAP1 deletion. BAP1 immunostain represents an excellent biomarker with an unprecedented specificity (100%) in the distinction between benign and malignant mesothelial proliferations. Finding BAP1 loss in mesothelial cells should prompt to immediately reevaluate the patient; moreover, it might be useful in mapping tumor extent and planning surgical resection.

Primary hepatic sarcomatoid carcinoma: A case report

Sarcomatoid carcinoma (SC) is a malignant tumor type of unclear pathogenesis, which rarely occurs in the liver. The present study reports the case of a 60-year-old woman who presented with multiple masses in her liver, with no fever, abdominal pain or jaundice. Serological markers for hepatitis B and C virus were negative, as was the test for α fetoprotein. Abdominal enhanced magnetic resonance imaging examination confirmed multiple lesions in the liver, and liquefactive necrosis was observed. The patient underwent a right hepatectomy, in addition to a cholecystectomy. Cytokeratin 8 (CK8), cluster of differentiation 117, pancytokeratin and vimentin were positively detected using immunohistochemistry, and thus the diagnosis of primary hepatic SC (PHSC) was established. During the follow-up period, characteristic imaging manifestations of tumor recurrence were detected, including peripheral enhancement, central necrosis, variable enhancement, venous invasion and intrahepatic metastasis. The immunohistochemical detection of CK, epithelial membrane antigen and vimentin, with CK8 as a critical indicator, may be useful for the diagnosis of PHSC. The preferred treatment for PHSC is surgical resection and the prognosis is poor.

Sarcomatoid Carcinoma of the lung: A rare case of three small intestinal intussusceptions and literature review

INTRODUCTION

Sarcomatoid carcinoma is an extremely rare, biphasic tumor characterized by a combination of malignant epithelial and mesenchymal cells. Limited data showed that most cases occurred with advanced local disease and metastasis.

PRESENTATION OF CASE

We present a rare case of a 60-year-old man with three small intestinal intussusceptions due to metastatic pulmonary carcinosarcoma. He was explored for chest pain and hemoptysis in Emergency room. Due to his chest symptoms he had a computed tomography (CT) scan of the chest which showed a lesion about 60mm in diameter in the inferior lobe of the left lung. After 2 weeks physical examination demonstrated a distended abdomen and auscultation was indicated by hyperactive bowel sounds. Further imaging studies with abdominal computed tomography (CT) scan, showed multiple protruding small bowel tumors with entero enteric intussusceptions at three sites requiring a massive bowel resection at surgery. The pathology showed that it was positive for cytokeratin, vimentin, CD-34, and LIS; CK7 was focally positive; and CD117, CD20, and desmine were negative. The final diagnosis was metastatic small bowel carcinosarcoma with a lung primary.

DISCUSSION

Lung carcinosarcoma is a high grade biphase neoplasm. The survival rate at 6 months is only around 27%.

CONCLUSION

There are rare reports of small intestinal intussusceptions caused by metastatic lung carcinosarcoma, this presentation shows the third case in literature. Physicians should be more alert to symptoms or signs indicating GI metastais in patients with a history of lung cancer.

Sarcomatoid mesothelioma: future advances in diagnosis, biomolecular assessment, and therapeutic options in a poor-outcome disease

Malignant pleural mesothelioma (MPM) is the most frequent pleural neoplasm, with asbestos exposure as one of the recognized carcinogen agents, causative in 80% of cases. The prognosis is poor; median survival of untreated cases is 6-9 months, with fewer than 5% of patients surviving 5 years. Sarcomatoid mesothelioma (SM) represents the subtype with the worst outcome and median survival ranging from 3.5 to 8 months. In the last few years, an accurate differentiation between the subtypes of MPM has become a crucial issue, due to differences in chemosensitivity and clinical outcome, and several studies have evaluated different immunohistochemical markers to better define the diagnosis. The different and worse outcome of patients with SM and, in general, nonepithelioid subtypes makes it intriguing to select these cases to better study the biomolecular profile in order to find factors linked to prognosis and/or predictive of therapeutic response. Considering recent studies on miRNA and genetic mapping, further investigation of this rare subtype might represent a field for basic and clinical-translational research providing for more tailored therapies.