Dose-escalation, tolerability, and efficacy of intratumoral and subcutaneous injection of hemagglutinating virus of Japan envelope (HVJ-E) against chemotherapy-resistant malignant pleural mesothelioma: a clinical trial.

The hemagglutinating virus of Japan envelope (HVJ-E) is an inactivated Sendai virus particle with antitumor effect and inducing antitumor immunity. However, its dosage and efficacy have not been verified. We conducted a phase I clinical study on chemotherapy-resistant malignant pleural mesothelioma (MPM) aiming to determine the recommended dosage for a phase II study through dose-limiting toxicity and evaluate HVJ-E's preliminary efficacy. HVJ-E was administered intratumorally and subcutaneously to the patients with chemotherapy-resistant MPM. While no serious adverse events occurred, known adverse events of HVJ-E were observed. In the preliminary antitumor efficacy using modified response evaluation criteria in solid tumors (RECIST) criteria, three low-dose patients exhibited progressive disease, while all high-dose patients achieved stable disease, yielding disease control rates (DCRs) of 0% and 100%, respectively. Furthermore, the dose-dependent effect of HVJ-E revealed on DCR modified by RECIST and the baseline changes in target lesion size (by CT and SUL-peak; p < 0.05). Comparing targeted lesions receiving intratumoral HVJ-E with non-injected ones, while no clear difference existed at the end of the study, follow-up cases suggested stronger antitumor effects with intratumoral administration. Our findings suggest that HVJ-E could be safely administered to patients with chemotherapy-resistant MPM at both study doses. HVJ-E exhibited some antitumor activity against chemotherapy-resistant MPM, and higher doses tended to have stronger antitumor effects than lower doses. Consequently, a phase II clinical trial with higher HVJ-E doses has been conducted for MPM treatment. Trial registration number: UMIN Clinical Trials Registry (#UMIN000019345).

Peritoneal Dissemination in Patients with Recurrence After Post-pleurectomy/decortication for Pleural Mesothelioma.

BACKGROUND: In clinical practice, peritoneal dissemination after curative-intent surgery for pleural mesothelioma occasionally recurs. This study investigated the risk factors and prognosis associated with post-pleurectomy/decortication peritoneal dissemination in pleural mesothelioma, which are rarely reported. METHODS: This retrospective review included 160 patients who experienced recurrence after pleurectomy/decortication for pleural mesothelioma between January 2011 and December 2021. Patients with recurrence were classified according to the initial recurrence pattern. The P group experienced recurrence with peritoneal dissemination, and the non-P group experienced recurrence without peritoneal dissemination. The analysis determined the risk factors for peritoneal dissemination using multivariable logistic regression analysis. Survival was analyzed using the Kaplan-Meier method and the log-rank test. RESULTS: Of the 160 patients, 20 (12.5%) exhibited peritoneal dissemination and were assigned to the P group, whereas 140 (87.5%) had recurrence without peritoneal dissemination and were assigned to the non-P group. Multivariable logistic regression analysis showed that diaphragm reconstruction (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.0-8.0; p = 0.048) and female sex (OR, 3.7; 95% CI 1.26-10.8; p = 0.017) were associated with the P group. Post-recurrence survival was worse in the P group than in the non-P group (1-year post-recurrence survival: 22.2% vs. 65.3%; median: 6.7 months vs. 19.4 months; p = 0.0013). CONCLUSIONS: Peritoneal dissemination occurred in approximately one of every eight patients with recurrence after pleurectomy/decortication for pleural mesothelioma, and the incidence was significantly higher among females and patients undergoing diaphragm reconstruction. Moreover, postoperative recurrence of peritoneal dissemination was associated with a poor prognosis.

Clinical Efficacy and Safety of Nivolumab in Malignant Non-Pleural Mesothelioma: A Multicenter, Open-Label, Single-Arm, Japanese Phase II Trial (Viola) Protocol.

BACKGROUND: There is no authorized treatment for malignant non-pleural mesothelioma (MNPM) worldwide. In contrast to malignant pleural mesothelioma, MNPM has not been investigated, and no treatment has been established due to its rarity. OBJECTIVES: This multicenter, open-label, single-arm, Japanese phase II trial aims at evaluating the efficacy and safety of nivolumab, an immune checkpoint inhibitor, in advanced or metastatic MNPM treatment. METHODS: This phase II trial commenced in October 2020. Twenty-three patients with advanced or metastatic MNPM who meet the inclusion and exclusion criteria were enrolled from five institutions within 2 years. Regardless of prior therapy, 240 mg of nivolumab will be administered intravenously to MNPM patients every 2 weeks to investigate its efficacy and safety until disease progression or unacceptable toxicities are detected, or the patient's condition meets the withdrawal criteria. RESULTS: The primary endpoint is the objective response rate by central assessment following the Response Evaluation Criteria in Solid Tumors version 1.1. The secondary endpoints include disease control rate, overall survival, progression-free survival, adverse events, and treatment-related adverse events. CONCLUSIONS: This is the first prospective investigator-initiated trial to evaluate the effect of nivolumab monotherapy for MNPM.

Efficacy and safety of nivolumab with ipilimumab for recurrent malignant pleural mesothelioma after primary surgical intervention.

BACKGROUND: Treatment of recurrent malignant pleural mesothelioma (MPM) remains challenging. Our study examined the efficacy, tolerability, and safety of nivolumab with ipilimumab treatment for recurrent MPM after primary curative-intent surgery. METHODS: Treatment comprised 360 mg nivolumab every 3 weeks and 1 mg/kg of ipilimumab every 6 weeks, both administered intravenously. Both were discontinued for progressive disease or serious adverse events (AEs). Additional post-treatment data were evaluated, including objective response rate (ORR), disease control rate (DCR), post-treatment survival, progression-free survival (PFS), and AEs. Tumor response was assessed using the modified Response Evaluation Criteria in Solid Tumors (RECIST 1.1). Survival analysis was estimated using a Kaplan-Meier plot. Feasibility analysis was performed using the National Cancer Institute Common Terminology Criteria for AEs version 5.0. RESULTS: Forty-one patients received nivolumab with ipilimumab for recurrent MPM after primary curative-intent surgery (median follow-up, 10.4 months; median treatment, 5.1 months). Overall, 18 patients exhibited partial response, 13 exhibited stable disease, and 10 had documented progressive disease. ORR and DCR were 43.9 and 75.6%, respectively. The 12-month post-treatment survival rate and PFS rate were 74.2 and 40.0%, respectively (median survival, not calculated; median PFS, 7.3 months). Further, 47 AEs were reported in 29 patients (70.7%), including grade 3-4 AEs in 14 patients (34.1%). Grade 4 hepatobiliary disorders were observed in 2 patients and grade 4 neutropenia was observed in 1. CONCLUSION: Nivolumab with ipilimumab treatment in patients with recurrent MPM after primary surgical treatment may be clinically efficacious, although serious AEs may be frequently observed.

Complications and Predictive Factors for Air Leak > 10 Days with Neoadjuvant Chemotherapy Followed by Pleurectomy/Decortication for Malignant Pleural Mesothelioma.

BACKGROUND: A few studies have reported the incidence and clinical implications of complications after pleurectomy/decortication (P/D). OBJECTIVE: The aim of this study was to assess the details of complications and predictive factors of particularly durable air leak with P/D. METHODS: Data on 163 consecutive patients who underwent neoadjuvant chemotherapy (NAC) followed by P/D for malignant pleural mesothelioma between September 2012 and May 2020 at our institution were retrospectively analyzed. Postoperative complications and the significance of various preoperative risk factors for air leak > 10 days (AL10) to identify the group having a higher risk for particularly durable air leak were investigated. Risk factors for AL10 were sought using univariate and multivariate analyses. RESULTS: Of 163 patients, 30- and 90-day mortality was 0.6% and 2.5%, respectively. Eighty-four (51.4%) patients experienced grade III or worse postoperative complications according to the Clavien-Dindo classification. The median duration of air leak was 7 postoperative days. AL10 occurred in 53 (32.5%) patients. Fifty-eight patients (35.6%) underwent pleurodesis and five patients (3.1%) underwent reoperation to control the air leak. On univariate analysis, performance status (PS; p = 0.003), prognostic nutritional index (p = 0.01), and pleural effusion (p = 0.04) were statistically significant risk factors for AL10, while on multivariate analysis, PS (odds ratio 4.0, 95% confidence interval 1.3-12.7; p = 0.02) remained the only variable predicted for AL10. CONCLUSIONS: Recent postoperative mortality rates in NAC followed by P/D are quite acceptable. Approximately one in every three patients experienced AL10, and PS may be a risk factor associated with AL10.

Irinotecan and Gemcitabine as Second-Line Treatment in Patients with Malignant Pleural Mesothelioma following Platinum plus Pemetrexed Chemotherapy: A Retrospective Study.

BACKGROUND: Cisplatin-pemetrexed combination chemotherapy is the current standard primary treatment for malignant pleural mesothelioma (MPM). It was first approved for untreated and unresectable MPM in the 2003 National Comprehensive Cancer Network (NCCN) guidelines. However, to date, standard treatments for patients with MPM who previously underwent chemotherapy, as recommended by the NCCN Malignant Pleural Mesothelioma guidelines, have been inadequate. To explore treatment options for such patients, we performed this retrospective study of patients who received irinotecan plus gemcitabine as second-line therapy for MPM. METHODS: We investigated 62 patients diagnosed with unresectable MPM between January 2008 and October 2017 who experienced recurrence following cisplatin treatment (or carboplatin) plus pemetrexed or pemetrexed monotherapy as first-line treatment, and who underwent irinotecan plus gemcitabine combination therapy as second-line treatment. Irinotecan (60 mg/m2) and gemcitabine (800 mg/m2) were administered on days 1 and 8 every 3 weeks, including a 1-week washout period. Our endpoints were efficacy, survival period, and toxicity. RESULTS: patients' median age was 65 years (range 50-79), and the histological MPM types were epithelioid (n = 48), sarcomatoid (n = 6), biphasic (n = 6), and desmoplastic (n = 2). One patient experienced a partial response, 40 had stable disease, and 21 had progressive disease. The disease control rate was 66.1% and the response rate 2.1%. Additionally, the median progression-free and overall survival time were 5.7 and 11.3 months, respectively. The most common adverse events were neutropenia (32.2%), loss of appetite (16.1%), nausea/diarrhea (11.3%), and thrombocytopenia/phlebitis (9.7%). Grade 3 adverse events included neutropenia (12.9%) and thrombocytopenia/phlebitis (2.1%); however, all adverse events were managed with symptomatic therapy. CONCLUSIONS: Despite the fact that second-line irinotecan plus gemcitabine combination therapy did not produce marked tumor shrinkage, it achieved a relatively high disease control rate of >65% with an acceptable toxicity profile. Hence, the combination of irinotecan plus gemcitabine may be considered for MPM treatment, with consideration of combination with immune checkpoint inhibitors as a potential next step.

The utility of 68F-FDG PET/CT for evaluation of tumor response to immune checkpoint inhibitor therapy and prognosis prediction in patients with non-small-cell lung cancer.

OBJECTIVE: To compare three fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) (EORTC criteria and PERCIST) and computed tomography (CT) (RECIST1.1) for response evaluation and prognosis prediction in non-small-cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitor (ICI) monotherapy. SUBJECTS AND METHODS: Forty NSCLC patients underwent 18F-FDG PET/CT scans at baseline and after 4 to 8 cycles of nivolumab or pembrolizumab. Therapeutic response was evaluated according to EORTC criteria, PERCIST, and RECIST1.1,then concordance among those was assessed using Cohen's κ coefficient. Progression-free survival (PFS) and overall survival (OS) was examined using log-rank and Cox methods. RESULTS: The number of complete metabolic response (CMR)/partial metabolic response (PMR)/stable metabolic disease (SMD)/progressive metabolic disease (PMD) were 8/10/4/18 for EORTC criteria and 9/9/4/18 for PERCIST. Using RECIST1.1, those of CR/PR/SD/PD were 4/10/12/14. Although there was high concordance between PERCIST and EORTC (92.5% of patients; κ=0.924), that between PERCIST and RECIST1.1 was substantial (65.0%; κ=0.560) and that between EORTC and RECIST1.1 (65.0%; κ=0.574). After a median 23.2 months (range 7.2 to 51.8 months), 32 patients had documented progression and 24 patients died from NSCLC. According to both PET and CT, patients with no progression (CMR/PMR/SMD or CR/PR/SD) showed significantly longer PFS and OS than PMD or PD patients (EORTC: P<0.0001 and P<0.0001, respectively, PERCIST: P<0.0001 and P=0.0001, respectively, RECIST1.1: P<0.0001 and P<0.0001, respectively). In a univariate analysis total MTV (P=0.042) on pre-ICI treatment 18F-FDGPET/CT scans was significantly associated with progression. Highest SUVmax (P<0.0001), total MTV (P=0.0062), total TLG (P<0.0001), highest SULpeak (P<0.0001), and total TLGL (P<0.0001) on post-ICI treatment 18F-FDG PET/CT scans were also were significantly associated with progression. Moreover, the change rate of highest SUVmax (P<0.0001), total metabolic tumor volume (MTV) (P<0.0001), total lesion glycolysis(TLG) (P<0.0001), highest SULpeak (P<0.0001), total TLGL (P<0.0001), size (P=0.0012), EORTC (P<0.0001), PERCIST (P<0.0001), and RECIST 1.1 (P<0.0001) on two PET/CT scans were significantly associated with progression. A multivariate analysis confirmed the change rate of total MTV (P=0.034), and total TLGL (P=0.0027), EORTC (P=0.018), PERCIST (P=0.045), and RECIST1.1 (P=0.0037) as independent negative PFS predictors. CONCLUSION: Both 18F-FDG PET (EORTC criteria and PERCIST) and CT (RECIST1.1) after 4 to 8ICI monotherapy cycles are accurate for evaluation of tumor response and predicting prognosis in NSCLC patients.

Quantitative 67Ga-citrate SPECT/CT for evaluating disease activity in patients with interstitial lung disease.

OBJECTIVE: To determine whether results of a standardized uptake value (SUV)-based semi-quantitative analytic method for gallium-67 (67Ga)-citrate single photon emission tomography/computed tomography (SPECT/CT) reflects disease activity in patients with interstitial lung disease. SUBJECTS AND METHODS: Gallium-67-citrate SPECT/CT was used to evaluate disease activity in 24 patients with interstitial pneumoniaon clinical grounds at a single institution from June 2018 to August 2020. SUV in a given volume of interest over the bilateral pulmonary parenchyma was calculated using a dosimetry software package. Correlations of maximum SUV (SUVmax) and mean SUV (SUVmean) with clinical factors, including KL-6, lactate dehydrogenase (LDH), and C-reactive protein (CRP), were evaluated in all 24, as well as in 15 patients with spirometry results using Pearson's rank correlation test. RESULTS: The mean bilateral pulmonary SUVmax value showed a moderately significant correlation with KL-6 (Pearson's correlation coefficient r=0.51, P=0.012) and LDH (r=0.51, P=0.010), a weak non-significant correlation with DLCO% (r=-0.26, P=0.34), and no correlation with CRP (r=-0.01, P=0.94), FVC% (r=0.11, P=0.71), or FEV1.0% (r=0.14, P=0.62). Eleven patients with high KL-6 (≥1000U/mL) were defined as having disease activity. Maximum SUV sensitivity, specificity, and accuracy for predicting interstitial lung disease activity were 72.7%, 76.9%, and 75.0%, respectively, with a best cut-off value of 3.78. CONCLUSION: Semi-quantitative values obtained with 67Ga-citrate SPECT/CT showed a moderate correlation with KL-6 and moderate diagnostic performance for predicting disease activity of interstitial lung disease. It is rather unlikely that quantitative 67Ga-citrate SPECT/CT will have a role into the algorithm of interstitial lung disease.

Tumor-associated macrophage-derived inflammatory cytokine enhances malignant potential of malignant pleural mesothelioma.

Malignant pleural mesothelioma (MPM) is an asbestos-related aggressive malignant neoplasm. Due to the difficulty of achieving curative surgical resection in most patients with MPM, a combination chemotherapy of cisplatin and pemetrexed has been the only approved regimen proven to improve the prognosis of MPM. However, the median overall survival time is at most 12 mo even with this regimen. There has been therefore a pressing need to develop a novel chemotherapeutic strategy to bring about a better outcome for MPM. We found that expression of interleukin-1 receptor (IL-1R) was upregulated in MPM cells compared with normal mesothelial cells. We also investigated the biological significance of the interaction between pro-inflammatory cytokine IL-1ß and the IL-1R in MPM cells. Stimulation by IL-1ß promoted MPM cells to form spheroids along with upregulating a cancer stem cell marker CD26. We also identified tumor-associated macrophages (TAMs) as the major source of IL-1ß in the MPM microenvironment. Both high mobility group box 1 derived from MPM cells and the asbestos-activated inflammasome in TAMs induced the production of IL-1ß, which resulted in enhancement of the malignant potential of MPM. We further performed immunohistochemical analysis using clinical MPM samples obtained from patients who were treated with the combination of platinum plus pemetrexed, and found that the overexpression of IL-1R tended to correlate with poor overall survival. In conclusion, the interaction between MPM cells and TAMs through a IL-1ß/IL-1R signal could be a promising candidate as the target for novel treatment of MPM (Hyogo College of Medicine clinical trial registration number: 2973).

Adenosine Deaminase in Pleural Effusion and Its Relationship with Clinical Parameters in Patients with Malignant Pleural Mesothelioma.

Pleural effusion adenosine deaminase (ADA) levels are elevated in various diseases. We investigated whether pleural effusion ADA levels differ among patients with malignant pleural mesothelioma (MPM), lung cancer (LC), and benign diseases, including tuberculous pleurisy. We examined 329 patients from February 2002 to July 2013. There were 131 MPM cases with ADA levels of 32.29 IU/L; 117 LC cases with ADA levels of 21.12 IU/L; 54 benign disease cases with ADA levels of 20.98 IU/L. A significant difference existed in pleural effusion ADA levels between MPM and benign disease patients. Pleural effusion ADA levels were significantly higher in MPM patients.

Initial evaluation of nivolumab in patients with post-operative recurrence of malignant pleural mesothelioma.

BACKGROUND: Limited options exist for treating post-recurrence patients with malignant pleural mesothelioma (MPM). This study aimed to evaluate the efficacy and feasibility of nivolumab in patients with post-operative recurrence of MPM in a real-world setting. METHODS: This study included 35 patients with post-operative recurrence of MPM. Treatment consisted of 240-mg intravenous nivolumab administration every 2 weeks until progressive disease (PD) or serious adverse events (AEs). Additional post-treatment data were evaluated, including objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), post-treatment survival and AEs. Tumor response was assessed using the modified Response Evaluation Criteria in Solid Tumors. Survival analysis was performed using the Kaplan-Meier method. The feasibility analysis including AEs was performed with the National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0. RESULTS: Of the 35 patients who received nivolumab, median follow-up was 6 months. The median treatment duration was 3 months (range: 1-14 months), and median of 8 cycles (range: 2-32 cycles) was administered. Best overall responses were follows: 1 patient had complete response, 6 had partial response, 18 had stable disease and 8 had PD. The ORR was 20.0%, and the DCR was 77.1%. The median overall survival and PFS were 13.1 and 4.4 months, respectively. There were grade-3 AEs in four patients (11.4%). No grade-4 or -5 AEs were observed. CONCLUSION: Nivolumab treatment in patients with post-operative recurrence of MPM seems safe and clinical efficacy.

EphA2 inhibition suppresses proliferation of small-cell lung cancer cells through inducing cell cycle arrest.

Small-cell lung cancer (SCLC) is characterized by one of neuroendocrine tumors, and is a clinically aggressive cancer due to its rapid growth, early dissemination, and rapid acquisition of multidrug resistance to chemotherapy. Moreover, the standard chemotherapeutic regimen in SCLC has not changed for three decades despite of the dramatic therapeutic improvement in non-SCLC. The development of a novel therapeutic strategy for SCLC has become a pressing issue. We found that expression of Eph receptor A2 (EphA2) is upregulated in three of 13 SCLC cell lines and five of 76 SCLC tumor samples. Genetic inhibition using siRNA of EphA2 significantly suppressed the cellular proliferation via induction of cell cycle arrest in SBC-5 cells. Furthermore, small molecule inhibitors of EphA2 (ALW-II-41-27 and dasatinib) also exclusively inhibited proliferation of EphA2-positive SCLC cells by the same mechanism. Collectively, EphA2 could be a promising candidate as a therapeutic target for SCLC.

Utility of polaprezinc in reducing toxicities during radiotherapy: a literature review.

Chemoradiotherapy is important for treating malignancies. However, radiation-induced toxicities develop as chemoradiotherapy-related complications. Various agents reduce or prevent toxicities, but there are no standard treatments. Polaprezinc (PZ), a chelating compound used for gastric ulcers, has antioxidant and free radical scavenging effects. Although few studies have evaluated PZ and radiation-induced normal tissue damage, several clinical studies have shown the efficacy of PZ for oral mucositis, esophagitis, proctitis and taste alterations during and after radiotherapy. Moreover, preclinical data support the clinical data, indicating good potential of testing PZ in future trials. However, as there are only few well-documented review articles on PZ use in cancer treatment, we conducted this literature review. PZ reduced several radiation-induced toxicities and improved the quality of life.

Adenosine deaminase inhibitor EHNA exhibits a potent anticancer effect against malignant pleural mesothelioma.

BACKGROUND/AIMS: Malignant pleural mesothelioma (MPM) is an aggressive malignant tumor and an effective therapy has been little provided as yet. The present study investigated the possibility for the adenosine deaminase (ADA) inhibitor EHNA as a target of MPM treatment. METHODS: MTT assay, TUNEL staining, monitoring of intracellular adenosine concentrations, and Western blotting were carried out in cultured human MPM cell lines without and with knocking-down ADA. The in vivo effect of EHNA was assessed in mice inoculated with NCI-H2052 MPM cells. RESULTS: EHNA induced apoptosis of human MPM cell lines in a concentration (0.01-1 mM)- and treatment time (24-48 h)-dependent manner, but such effect was not obtained with another ADA inhibitor pentostatin. EHNA increased intracellular adenosine concentrations in a treatment time (3-9 h)-dependent manner. EHNA-induced apoptosis of MPM cells was mimicked by knocking-down ADA, and the effect was neutralized by the adenosine kinase inhibitor ABT-702. EHNA clearly suppressed tumor growth in mice inoculated with NCI-H2052 MPM cells. CONCLUSION: The results of the present study show that EHNA induces apoptosis of MPM cells by increasing intracellular adenosine concentrations, to convert to AMP, and effectively prevents MPM cell proliferation. This suggests that EHNA may be useful for treatment of the tragic neoplasm MPM.

Suppression of heme oxygenase-1 activity reduces airway hyperresponsiveness and inflammation in a mouse model of asthma.

OBJECTIVE: Carbon monoxide (CO) levels in expired gas are higher in patients with bronchial asthma than in healthy individuals. Heme oxygenase-1 (HO-1) is a rate-limiting enzyme that catalyzes the degradation of heme to yield biliverdin, CO and free iron. Thus, HO-1 is implicated in the pathogenesis of bronchial asthma. However, whether HO-1 expression and activity in lung tissue are related to allergic airway inflammation remains unclear. We investigated whether expression of HO-1 is related to allergic airway inflammation in lungs and whether HO-1 could influence airway hyperresponsiveness and eosinophilia in mice sensitized to ovalbumin (OVA). METHODS: C57BL/6 mice immunized with OVA were challenged thrice with an aerosol of OVA every second day for 8 days. HO-1-positive cells were identified by immunostaining in lung tissue, and zinc protoporphyrin (Zn-PP), a competitive inhibitor of HO-1, was administered intraperitoneally to OVA-immunized C57BL/6 mice on day 23 (day before inhalation of OVA) and immediately before inhalation on the subsequent 4 days (total five doses). Mice were analyzed for effects of HO-1 on AHR, inflammatory cell infiltration and cytokine levels in lung tissue. Ethical approval was obtained from the concerned institutional review board. RESULTS: Number of HO-1-positive cells increased in the subepithelium of the bronchi after OVA challenge, and HO-1 localized to alveolar macrophages. Zn-PP clearly inhibited AHR, pulmonary eosinophilia and IL-5 and IL-13 expression in the lung tissue. CONCLUSION: Expression of HO-1 is induced in lung tissue during attacks of allergic bronchial asthma, and its activity likely amplifies and prolongs allergic airway inflammation.

Circulating tumor cells (CTCs) in malignant pleural mesothelioma (MPM).

PURPOSE: To investigate the diagnostic and prognostic value of circulating tumor cells (CTCs), a potential surrogate of micrometastasis, in malignant pleural mesothelioma (MPM). METHODS: We prospectively evaluated CTCs in 7.5 mL of peripheral blood sampled from patients with a suspicion of MPM. A semiautomated system was used to capture CTCs with an antibody against the epithelial cell adhesion molecule. RESULTS: Of 136 eligible patients, 32 were finally diagnosed with nonmalignant diseases (NM), and 104 had MPM. CTCs were detected in 32.7 % (34 of 104) of MPM patients but in only 9.4 % (3 of 32) of NM patients (P = 0.011). The CTC count was significantly higher in MPM patients than in NM patients (P = 0.007), and a receiver operating characteristic (ROC) curve analysis showed an insufficient capability of the CTC test in discrimination between MPM and NM, with an area under ROC curve of 0.623 (95 % confidence interval, 0.523-0.723; P = 0.036). Among MPM patients, CTCs were more frequently detected in patients with epithelioid subtype (39.7 %, 31 of 78) than in those with nonepithelioid subtypes (11.5 %, 3 of 26; P = 0.016). Positive CTCs (CTC count ≥ 1) were a significant factor to predict a poor prognosis among epithelioid patients (median overall survival, 22.3 months for positive CTCs vs. 12.6 months for negative CTCs; P = 0.004) and not in nonepithelioid patients (P = 0.649). A multivariate analysis showed that positive CTCs were a significant and independent factor to predict a poor prognosis (hazard ratio, 2.904; 95 % confidence interval, 1.530-5.511; P = 0.001) for epithelioid MPM patients. CONCLUSIONS: CTC was a promising marker in diagnosis and prediction of prognosis in MPM, especially in epithelioid MPM.

True Benefits of Immune Checkpoint Inhibitors in the Treatment of Malignant Pleural Mesothelioma in Japan.

In February 2004, the Food and Drug Administration (FDA) was the first to approve the combination of cisplatin (CDDP) and pemetrexed (PEM) as standard first-line chemotherapy for untreated, unresectable malignant pleural mesothelioma (MPM). However, after that approval, no progress was made in the standard first-line treatment of MPM for almost 15 years. Positive results from a phase 3 study (Mesothelioma Avastin Cisplatin Pemetrexed Study: MAPS) verifying the effect of bevacizumab, an anti-angiogenesis agent added to CDDP/PEM for unresectable MPM, were published in The Lancet in December 2015; however, this did not lead to approval by national drug regulatory agencies. Furthermore, no second-line treatment was established for cases refractory to CDDP/PEM. In August 2018, the Pharmaceuticals and Medical Devices Agency of Japan was the first in the world to approve monotherapy with nivolumab, an immune checkpoint inhibitor (ICI), for previously unresectable, advanced, or recurrent MPM. Following Japan, in October 2020, the FDA approved the combination of nivolumab and ipilimumab for the treatment of previously untreated, unresectable MPM. In this article, we review the transition of drug treatment for MPM, in light of the historical background, focusing on the benefits of ICIs.

Comparison of FDG-PET/CT and CT for evaluation of tumor response to nivolumab plus ipilimumab combination therapy and prognosis prediction in patients with unresectable malignant pleural mesothelioma.

OBJECTIVES: Results for malignant pleural mesothelioma (MPM) patients following first-line treatment with nivolumab plus ipilimumab obtained with immunotherapy-modified PERCIST (imPERCIST), shown by [18F]fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT), and modified RECIST (mRECIST), shown by CT, were compared for response evaluation and prognosis prediction. RESULTS: imPERCIST indicated nine progressive metabolic disease (PMD), eight stable metabolic disease (SMD), four partial metabolic response (PMR), and five complete metabolic response (CMR) cases. mRECIST showed nine with progressive disease (PD), nine stable disease (SD), seven partial response (PR), and one complete response (CR). Although high concordance was noted (κ = 0.827), imPERCIST correctly judged a greater percentage with CMR (15.4%). Following a median 10.0 months, 15 patients showed progression and eight died from MPM. With both, progression-free survival (PFS) and overall survival (OS) were significantly longer in patients without progression (CMR/PMR/SMD, CR/PR/SD, respectively) as compared to PMD/PD patients (imPERCIST p < 0.0001 and p = 0.015, respectively; mRECIST p < 0.0001 and p = 0.015, respectively). METHODS: Twenty-six patients (23 males, 3 females; median 73.5 years) with histologically proven MPM and no curative surgery received nivolumab plus ipilimumab combination therapy. FDG-PET/CT and diagnostic CT scanning at the baseline, and after 2-4 cycles (2 in three, 3 in 17, 4 in six patients) were performed. Therapeutic response findings evaluated using imPERCIST and mRECIST were compared. PFS and OS analyses were done using log-rank and Cox methods. CONCLUSION: For unresectable MPM patient examinations, FDG-PET and CT provide accurate findings for evaluating tumor response and also prognosis prediction following first-line nivolumab plus ipilimumab immunotherapy (approximately three cycles).