A Case of Mediastinal Localized Malignant Pleural Mesothelioma Successfully Treated by Chemotherapy and Conversion Surgery

Localized malignant mesothelioma is a rare disease and little is known about its treatment strategy. We herein report a case of localized malignant pleural mesothelioma that had infiltrated into the anterior mediastinum, which was successfully treated using chemotherapy and conversion surgery. A 63-year-old man with a mediastinal tumor was referred to our hospital. Pathologic analysis of the biopsy specimen showed malignant mesothelioma. Significant tumor shrinkage by cisplatin and pemetrexed was observed and he underwent radical surgery via a median sternotomy. The patient has been disease free for 12 months

Therapeutic Outcomes of 15 Postoperative Bronchopleural Fistulas Including Seven Endoscopic Interventions

Therapeutic approaches to bronchopleural fistula (BPF) closure after lung resection are surgical or endoscopic interventions. We evaluated therapeutic outcomes to determine the optimal approach. We reviewed 15 patients who had developed BPF after lung resection for thoracic malignant diseases at our institution in the 10 years since 2008. The patients were 11 men and 4 women (mean age 68 years). We performed one pneumonectomy, 6 lobectomies, 7 segmentectomies, and one partial resection for malignant diseases. The median interval from lung resection to the BPF diagnosis was 46 days. The BPF-associated mortality rate was 26.7% (4/15). The rate of successful BPF closure was 66.6% (10/15). The endoscopic and surgical intervention success rates were 14.2% (1/7) and 69.2% (9/13), respectively (p<0.01). Of 5 patients who had failed BPF treatments, 4 died, and one transferred out without BPF closure. The therapeutic outcomes were related to preoperative comorbidities, performance status at the BPF diagnosis, time intervals from lung resection to BPF diagnosis, and presence of active pneumonia. The difference between endoscopic and surgical outcomes was nonsignificant, although the surgical intervention success rate was somewhat higher. The selection of endoscopic or surgical intervention for BPF does not significantly affect therapeutic outcomes

Crizotinib for recurring non-small-cell lung cancer with EML4-ALK fusion genes previously treated with alectinib: A phase II trial

Background The efficacy of crizotinib treatment for recurring EML4‐ALK‐positive non‐small cell lung cancer (NSCLC) previously treated with alectinib is unclear. Based on our preclinical findings regarding hepatocyte growth factor/mesenchymal epithelial transition (MET) pathway activation as a potential mechanism of acquired resistance to alectinib, we conducted a phase II trial of the anaplastic lymphoma kinase/MET inhibitor, crizotinib, in patients with alectinib‐refractory, EML4‐ALK‐positive NSCLC. Methods Patients with ALK‐rearranged tumors treated with alectinib immediately before enrolling in the trial received crizotinib monotherapy. The objective response rate was the primary outcome of interest. Results Nine (100%) patients achieved a partial response with alectinib therapy with a median treatment duration of 6.7 months. Crizotinib was administered with a median treatment interval of 50 (range, 20–433) days. The overall response rate was 33.3% (90% confidence interval [CI]: 9.8–65.5 and 95% CI: 7.5–70.1), which did not reach the predefined criteria of 50%. Two (22%) patients who achieved a partial response had brain metastases at baseline. Progression‐free survival (median, 2.2 months) was not affected by the duration of treatment with alectinib. The median survival time was 24.1 months. The most common adverse events were an increased aspartate transaminase/alanine transaminase (AST/ALT) ratio (44%) and appetite loss (33%); one patient developed transient grade 4 AST/ALT elevation, resulting in treatment discontinuation. Other adverse events were consistent with those previously reported; no treatment‐related deaths occurred. Conclusions Although the desired response rate was not achieved, crizotinib monotherapy following treatment with alectinib showed efficacy alongside previously described adverse events

Src mediates ERK reactivation in gefitinib resistance in non-small cell lung cancer

To study epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) resistance mechanisms, we established a novel gefitinib-resistant lung cancer cell line derived from an EGFR-mutant non-small cell lung cancer cell line (PC-9) pretreated with 4-(methylnitrosamino)1-(3-pyridy1)-1-butanone (designated PC9-GR). We found that gefitinib substantially suppressed the EGFR signaling pathway, whereas ERK was reactivated after several hours in PC9-GR but not in PC-9. The combination of gefitinib with ERK inhibition (by U0126) restored gefitinib susceptibility in PC9-GR, but PI3K-Akt inhibition with LY294002 did not. Although the levels of phosphorylated Src were up-regulated simultaneously with ERK reactivation, neither ERK suppression using U0126 nor an ERK-specific siRNA induced Src phosphorylation. Furthermore, dual inhibition of EGFR and Src restored gefitinib sensitivity in PC9-GR in vitro and in vivo. In conclusion, our results indicate that Src-mediated ERK reactivation may play a role in a novel gefitinib resistance mechanism, and that the combined use of gefitinib with a Src inhibitor may be a potent strategy to overcome this resistance

Utility of immune checkpoint inhibitors in non-small-cell lung cancer patients with poor performance status

Most clinical trials of non-small-cell lung cancer (NSCLC) exclude patients with poor ECOG performance status (PS). Thus, the efficacy of immune checkpoint inhibitors (ICIs) in patients with poor PS remains unclear. Herein, we used data from a retrospective cohort to assess the potential clinical benefits of ICIs in NSCLC patients with poor PS. Data from NSCLC patients who received ICI monotherapy at 9 institutions between December 2015 and May 2018 were retrospectively analyzed. After excluding 4 patients who lacked PS data, a total of 527 ICI-treated patients, including 79 patients with PS 2 or higher, were used for our analyses. The progression-free survival (PFS) and overall survival (OS) of patients with PS 2 or higher were significantly shorter compared with those of PS 0-1 patients (median PFS, 4.1 vs 2.0 months;P < .001 and median OS, 17.4 vs 4.0 months;P < .001). Among NSCLC patients with programmed cell death protein-ligand 1 (PD-L1) expression of 50% or higher who were treated with pembrolizumab as first-line therapy, the median PFS times of patients with PS 2 and 0-1 were 7.3 and 8.1 months, respectively. There was no significant difference in PFS between patients with PS 2 and 0-1 (P = .321). Although poor PS was significantly associated with worse outcomes in NSCLC patients treated with ICIs, pembrolizumab as a first-line treatment in NSCLC patients expressing high levels of PD-L1 could provide a clinical benefit, even in patients with PS 2

Subpopulation of small-cell lung cancer cells expressing CD133 and CD87 show resistance to chemotherapy

Tumors are presumed to contain a small population of cancer stem cells (CSCs) that initiate tumor growth and promote tumor spreading. Multidrug resistance in CSCs is thought to allow the tumor to evade conventional therapy. This study focused on expression of CD133 and CD87 because CD133 is a putative marker of CSCs in some cancers including lung, and CD87 is associated with a stem-cell-like property in small-cell lung cancer (SCLC). Six SCLC cell lines were used. The expression levels of CD133 and CD87 were analyzed by real-time quantitative reverse transcription-polymerase chain reaction and flow cytometry. CD133+/- and CD87+/- cells were isolated by flow cytometry. The drug sensitivities were determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Non-obese diabetic/severe combined immunodeficiency mice were used for the tumor formation assay. SBC-7 cells showed the highest expression levels of both CD133 and CD87 among the cell lines. CD133-/CD87-, CD133+/CD87-, and CD133-/CD87+ cells were isolated from SBC-7 cells; however, CD133+/CD87+ cells could not be obtained. Both CD133+/CD87- and CD133-/CD87+ subpopulations showed a higher resistance to etoposide and paclitaxel and greater re-populating ability than the CD133-/CD87- subpopulation. CD133+/CD87- cells contained more G0 quiescent cells than CD133-/CD87- cells. By contrast, CD133-/CD87- cells showed the highest tumorigenic potential. In conclusion, both CD133 and CD87 proved to be inadequate markers for CSCs; however, they might be beneficial for predicting resistance to chemotherapy. (Cancer Sci 2013; 104: 7884

Everolimus prolonged survival in transgenic mice with EGFR-driven lung tumors

Everolimus is an orally administered mTOR inhibitor. The effect, and mechanism of action, of everolimus on lung cancers with an epidermal growth factor receptor (EGFR) mutation remain unclear. Four gefitinib-sensitive and -resistant cell lines were used in the present work. Growth inhibition was determined using the MTT assay. Transgenic mice carrying the EGFR L858R mutation were treated with everolimus (10 mg/kg/day), or vehicle alone, from 5 to 20 weeks of age, and were then sacrificed. To evaluate the efficacy of everolimus in prolonging survival, everolimus (10 mg/kg/day) or vehicle was administered from 5 weeks of age. The four cell lines were similarly sensitive to everolimus. Expression of phosphorylated (p) mTOR and pS6 were suppressed upon treatment with everolimus in vitro, whereas the pAKT level increased. The numbers of lung tumors with a long axis exceeding 1 mm in the everolimus-treated and control groups were 1.9 +/- 0.9 and 9.4 +/- 3.2 (t-test, p<0.001), respectively. pS6 was suppressed during everolimus treatment. Although apoptosis and autophagy were not induced in everolimus-treated EGFR transgenic mice, angiogenesis was suppressed. The median survival time in the everolimus-treated group (58.0 weeks) was significantly longer than that in the control group (31.2 weeks) (logrank test, p<0.001). These findings suggest that everolimus had an indirect effect on tumor formation by inhibiting angiogenesis and might be effective to treat lung tumors induced by an activating EGFR gene mutation