Malignant pleural mesothelioma with an EML4-ALK fusion: Expect the unexpected!

Case report of malignant pleural mesothelioma with an ALK gene rearrangement, detected by FISH and confirmed by RNA-based next-generation sequencing. The co-occurrence of ALK gene fusions with the more common genetic alterations in CDKN2A, NF2 and BAP1 has, to our best knowledge, not yet been described in malignant mesothelioma. Furthermore, this unexpected finding could suggest a potential target for therapy in this subset of malignant mesotheliomas.

The Oncolytic Caprine Herpesvirus 1 (CpHV-1) Induces Apoptosis and Synergizes with Cisplatin in Mesothelioma Cell Lines: A New Potential Virotherapy Approach.

Malignant mesothelioma (MM) is an aggressive asbestos-related cancer, against which no curative modalities exist. Oncolytic virotherapy is a promising therapeutic approach, for which MM is an ideal candidate; indeed, the pleural location provides direct access for the intra-tumoral injection of oncolytic viruses (OVs). Some non-human OVs offer advantages over human OVs, including the non-pathogenicity in humans and the absence of pre-existing immunity. We previously showed that caprine herpesvirus 1 (CpHV-1), a non-pathogenic virus for humans, can kill different human cancer cell lines. Here, we assessed CpHV-1 effects on MM (NCI-H28, MSTO, NCI-H2052) and non-tumor mesothelial (MET-5A) cells. We found that CpHV-1 reduced cell viability and clonogenic potential in all MM cell lines without affecting non-tumor cells, in which, indeed, we did not detect intracellular viral DNA after treatment. In particular, CpHV-1 induced MM cell apoptosis and accumulation in G0/G1 or S cell cycle phases. Moreover, CpHV-1 strongly synergized with cisplatin, the drug currently used in MM chemotherapy, and this agent combination did not affect normal mesothelial cells. Although further studies are required to elucidate the mechanisms underlying the selective CpHV-1 action on MM cells, our data suggest that the CpHV-1-cisplatin combination could be a feasible strategy against MM.

The Collagen Receptor uPARAP in Malignant Mesothelioma: A Potential Diagnostic Marker and Therapeutic Target.

Malignant mesothelioma (MM) is a highly aggressive cancer with limited therapeutic options. We have previously shown that the endocytic collagen receptor, uPARAP, is upregulated in certain cancers and can be therapeutically targeted. Public RNA expression data display uPARAP overexpression in MM. Thus, to evaluate its potential use in diagnostics and therapy, we quantified uPARAP expression by immunohistochemical H-score in formalin-fixed paraffin-embedded bioptic/surgical human tissue samples and tissue microarrays. We detected pronounced upregulation of uPARAP in the three main MM subtypes compared to non-malignant reactive mesothelial proliferations, with higher expression in sarcomatoid and biphasic than in epithelioid MM. The upregulation appeared to be independent of patients' asbestos exposure and unaffected after chemotherapy. Using immunoblotting, we demonstrated high expression of uPARAP in MM cell lines and no expression in a non-malignant mesothelial cell line. Moreover, we showed the specific internalization of an anti-uPARAP monoclonal antibody by the MM cell lines using flow cytometry-based assays and confocal microscopy. Finally, we demonstrated the sensitivity of these cells towards sub-nanomolar concentrations of an antibody-drug conjugate formed with the uPARAP-directed antibody and a potent cytotoxin that led to efficient, uPARAP-specific eradication of the MM cells. Further studies on patient cohorts and functional preclinical models will fully reveal whether uPARAP could be exploited in diagnostics and therapeutic targeting of MM.

Case of a 57-Year-Old Man With Malignant Mesothelioma Presenting With Miliary Nodules on Chest Imaging.

CASE PRESENTATION: A 57-year-old man with history of stage IIIB right-sided malignant pleural mesothelioma was admitted from his oncologist's office for progressive dyspnea of two weeks duration. He had associated dyspnea at rest and a new dry cough. He denied sputum production, hemoptysis, or fevers, but he did endorse chills, fatigue, and weight loss. The patient was a veteran of the Navy and had extensive international travel in his 20s. He had never been incarcerated and denied any sick contacts or recent travels. He had received a diagnosis of mesothelioma 11 months earlier after presenting to his physician's office with complaints of shortness of breath on exertion. Initial imaging revealed a large right-sided pleural effusion with irregular pleural thickening. He underwent right-sided thoracoscopy, and the pleural biopsy result was consistent with epithelioid mesothelioma. Because of invasion of his seventh rib, he was not a candidate for surgery and underwent palliative radiation and chemotherapy with cisplatin, pemetrexed, and bevacizumab. He was undergoing his eighth cycle of chemotherapy at the time of presentation.

Malignant mesothelioma: A clinicopathological study of 76 cases with emphasis on immunohistochemical evaluation along with review of the literature.

INTRODUCTION: Malignant mesothelioma is an aggressive neoplasm arising from serosal lining and has a poor prognosis. Definite diagnosis requires confirmation through a biopsy; however, it is sometimes difficult on microscopic evaluation alone and requires the use of a wide panel of immunohistochemical markers. So, immunohistochemistry (IHC) is of paramount importance and must be routinely used for a definite diagnosis. Till date, very few studies on morphology and detailed IHC markers of mesothelioma have been reported from India. AIMS: To analyze the histomorphological findings of malignant mesothelioma, study the utility and role of the various immunohistochemical markers. MATERIAL AND METHODS: A total of 76 cases of mesotheliomas diagnosed at a tertiary cancer center in Udaipur were analyzed retrospectively from January 2015 to January 2020. Comprehensive data were analyzed including demographic, clinical, radiological, histopathological features along with a wide panel of IHC markers. RESULTS: Mesothelioma occurs over a wide age range from 40 to 70 years. It most commonly involved pleura in 68 cases (89.47%) with very few cases from the peritoneum. On computed tomography (CT) scan, nodular pleural or peritoneal thickening was present. On microscopy, the most common histopathological type was epithelioid mesothelioma (58 cases, 74.3%) followed by sarcomatous (9 cases, 12.8%), deciduoid (6 cases, 8.6%), and 3 cases of biphasic (4.3%). On IHC, WT1, mesothelin, and calretinin markers were positive in 85.91%, 80%, and 93.33% cases of mesothelioma, respectively. Other markers were helpful to rule out differential diagnosis in difficult scenarios. CONCLUSION: Therefore, the correlation of histopathology with clinico-radiological findings and judicious use of a panel of IHC markers is required for routine evaluation and definite diagnosis. IHC is also useful in situations with similar morphological spectrum in specific locations.

The usefulness of biomarkers in diagnosis of asbestos-induced malignant pleural mesothelioma.

INTRODUCTION: Malignant pleural mesothelioma (MPM) is a malignant tumor that is associated mostly with asbestos exposure. The present study was to evaluates the diagnostic value of neopterin, periostin, YKL-40, Tenascin-C (TNC), and Indolamine 2,3-dioxygenase (IDO) as noninvasive markers of malign pleural mesothelioma. METHODS: Included in the study were 30 patients diagnosed with malign pleural mesothelioma, and 25 people as a control group. Biomarker levels were determined using an enzyme immunoassay . A Mann-Whitney U test and Spearman correlation methods were used for the statistical analysis. RESULTS: All evaluated biomarkers were found to be significantly higher in the MPM group than in the control group (p < 0.05). There was no effect of such variables as gender, age or MPMsubtype on the parameters (p > 0.05) in the patient group. All biomarkers were positively correlated with each other (p < 0.001). CONCLUSIONS: The current non-invasive biomarkers that can be used in the diagnosis of MPM yielded significant results and can make important contributions to the early diagnosis of MPM.

Does the LENT score risk-stratify patients with malignant pleural mesothelioma? An observational study.

BACKGROUND: Malignant pleural mesothelioma (MPM) is a rare, highly aggressive and deadly disease with a poor patient life expectancy. A few years ago, the main challenge was the histological diagnosis of this disease; at present, the search for the best therapeutic strategy is now a priority. However, an optimal therapeutic strategy is not yet clear, despite growing efforts in the treatment armamentarium and research, and at the era of tailored and individualized treatment, tools to predict patient survival are needed for therapeutic decision-making. Among them, the LENT scoring system was developed to predict prognosis in patients with malignant pleural effusion. The aim of this study was to assess the performance of the LENT score in predicting prognosis in patients with MPM. METHODS: A retrospective observational study was conducted by analyzing the prospective collected databases of patients undergoing medical thoracoscopy in a single center with a final diagnosis of MPM confirmed by the MESOPATH National Reference Center. RESULTS: A total of 41 patients with MPM were studied. All patients underwent platinum-based chemotherapy combined with pemetrexed ± bevacizumab. No high-risk category patients were found using the LENT scoring system in this cohort. The median (range) LENT score at the time of medical thoracoscopy was 0 (0-3) and the median survival was 15.5 (2-54) months for the entire cohort. The median survival of low-risk and moderate-risk category patients was 21.4 months (2-54, 32 patients) and 6.7 months (2-19, nine patients), respectively. A total of 27 patients with MPM of epithelial subgroup had a median LENT score of 1 (0-2) with a 26 (2-54) months median survival. The median LENT score and median survival of nonepithelial mesothelioma patients (biphasic MPM subgroup, eight patients; sarcomatoid MPM subgroup, six patients) were 0 (0-3) and 11 (2-52) months, respectively. CONCLUSIONS: Applied to a homogenous cohort of MPM patients, the LENT score underestimated prognosis and was not useful per se for the management of this disease, as evidenced in the epithelial mesothelioma subgroup of patients in our study.

Clinicopathological characteristics of primary peritoneal epithelioid mesothelioma of clear cell type: A case report.

RATIONALE: Primary peritoneal epithelioid mesothelioma of clear cell type is an extremely rare entity composed of clear cytoplasm. It is challenging to diagnose because of the morphological resemblance to clear cell tumor. PATIENTS CONCERNS: A 69-year-old male patient had swollen lymph nodes in the right inguinal region for 7 months and was constipated for 1 month. DIAGNOSIS: The patient was diagnosed as peritoneal epithelioid mesothelioma of clear cell type based on computed tomography scan, pathology, immunohistochemistry, special staining and whole-exome sequencing. This patient harbored VHL gene alteration in exon 1 and homologous recombination defect (with a score of 45). This finding indicated that this patient might be sensitive to platinum-based therapy and Poly ADP-ribose Polymerase (PARP) inhibitor. This patient carried no microsatellite instability, a low level of tumor mutation burden, and a high extent of intratumoral heterogeneity. Eighteen neoantigens were detected. INTERVENTIONS: The patient received surgery-based multidisciplinary treatment by integrating cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). HIPEC was administered with docetaxel 120 mg plus cisplatin 120 mg, at 43°C, for 60 minutes. After operation, the patient received intravenous (IV) chemotherapy with docetaxel 60 mg, pemetrexed 750 mg and cisplatin 100 mg, and then intraperitoneal (IP) chemotherapy with docetaxel 40 mg. The patient received interventional therapy of hepatic artery embolization for 5 times. OUTCOMES: Regular follow-up was performed until Oct 14, 2020. The patient died 31.6 months later owing to incomplete intestinal obstruction. LESSONS: Primary peritoneal epithelioid mesothelioma of clear cell type needs to be differentiated from a variety of clear cell tumors. This disease is characterized by specific genetic alteration. Whole-exome sequencing contributes to guide individualized therapy. CRS-HIPEC helps achieve long-term overall survival.

Prolonged Progression-Free Survival in a Patient With Malignant Pleural Mesothelioma Following Korean Herbal Medicine Treatment Alone: A Case Report.

Korean herbal medicine treatment (KHMT) involves treating with a combination of natural products, which have been used for thousands of years. Recently, it has been reported to be effective and safe in cancer patients. This case report demonstrates the efficacy of KHMT in a 49-year-old man with malignant pleural mesothelioma (MPM), a rare and highly aggressive cancer. The patient showed recurrent pleural effusion and was diagnosed with epithelioid MPM at cT3NxM0 stage III in December 2017. The multidisciplinary care team recommended multimodal treatment based on an extrapleural pneumonectomy, but he refused this because the treatment was aggressive and the effectiveness was unclear. He decided to undergo pemetrexed plus cisplatin chemotherapy if his condition worsened. He visited the Korean Medicine Cancer Center for alternative treatment options. A KHMT regimen, consisting of twice-daily Gunchil-dan and thrice-daily Bangam-tang, was initiated in December 2017. Since commencement of KHMT, computed tomography and X-ray imaging scans have shown no significant interval changes and progression. At 21 months into treatment (September 2019), no significant adverse events have occurred. Given that the median overall survival of patients with MPM is approximately 1 year, the ongoing progression-free survival of this patient for 21 months is relatively long. This case, therefore, suggests that KHMT is a potential treatment option for MPM patients.