Masaru Matsumoto

Acute exacerbation (AEx) of interstitial pneumonia is the most common lethal adverse event related to the pharmacological treatment of patients with lung cancer complicated with interstitial pneumonia. Although small cell lung cancer (SCLC) is linked to poor prognosis, it exhibits good response to chemotherapy. Few previous research studies have investigated the safety and efficacy of treatment for advanced SCLC complicated with idiopathic interstitial pneumonia (IIP). We conducted a single-arm phase II study to evaluate the safety and efficacy of carboplatin plus etoposide for the treatment of patients with SCLC complicated with IIP. Chemotherapy-naïve patients with advanced SCLC complicated with IIP were enrolled. Patients received carboplatin every 21–28 days at a dose of area under the curve 4–6 on day 1 and etoposide at a dose of 80–100 mg/m2 on days 1–3. Thirty-one patients were enrolled between December 2009 and December 2022. A median of four cycles of carboplatin plus etoposide were administered. Acute exacerbation of idiopathic interstitial pneumonia was not observed; the rate of AEx was 0% (95% confidence interval [CI]: 0–9.6%, p = 0.038). The objective response rate was 83.9% (95% CI: 82.5–85.2). The median progression-free survival and overall survival were 5.9 (95% CI: 4.7–6.8) months and 14.0 (95% CI: 7.6–27.6) months, respectively. The 1-year survival rate was 61% (95% CI 41–76). The carboplatin plus etoposide treatment was tolerable and effective in SCLC patients complicated with IIP.

A 73-year-old man with lung squamous cell carcinoma was administered carboplatin + nab-paclitaxel + pembrolizumab for four cycles. Subsequently, he presented with multiple purpuras on his extremities, joint swelling on his fingers, abdominal pain, and diarrhea, accompanied by acute kidney injury (AKI), increased proteinuria, hematuria, and elevated C-reactive protein levels. Skin biopsy showed leukocytoclastic vasculitis as well as IgA and C3 deposition in the vessel walls. Based on these findings, the patient was diagnosed with IgA vasculitis as an immune-related adverse event (irAE) induced by carboplatin + nab-paclitaxel + pembrolizumab. After discontinuation of pembrolizumab and glucocorticoids, the symptoms immediately resolved. Regular monitoring of skin, blood tests, and urinalysis are necessary, and the possibility of irAE IgA vasculitis should be considered in cases of purpura and AKI during treatment with immune checkpoint inhibitors.

The relationship between lung cancer surgery and venous thromboembolism (VTE) in Japan has not been elucidated. This was a post hoc analysis of the Cancer-VTE Registry. The 1057 patients who underwent surgery for lung cancer were divided into the surgery alone (SA) group (n = 598) and the surgery plus chemotherapy (SC) group (n = 459), and the 1-year incidences of VTE and cerebral ischemia were analyzed. In the SA and SC groups, composite VTE was observed in one (0.2%) and 15 (3.3%) patients, respectively, and cerebral ischemia was observed in eight (1.3%) and four (0.9%) patients, respectively. Lymph node metastasis was more common in patients with D-dimer >1.2 μg/ml (odds ratio: 1.781, P = .004). SA had a low risk of VTE but a high risk of cerebral ischemia. Chemotherapy increases the risk of VTE. The D-dimer level was related to VTE and advanced cancer.

Osimertinib induces a marked response in non–small‐cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) gene mutations. However, acquired resistance to osimertinib remains an inevitable problem. In this study, we aimed to investigate osimertinib‐resistant mechanisms and evaluate the combination therapy of afatinib and chemotherapy. We established osimertinib‐resistant cell lines (PC‐9‐OR and H1975‐OR) from EGFR‐mutant lung adenocarcinoma cell lines PC‐9 and H1975 by high exposure and stepwise method. Combination therapy of afatinib plus carboplatin (CBDCA) and pemetrexed (PEM) was effective in both parental and osimertinib‐resistant cells. We found that expression of thrombospondin‐1 (TSP‐1) was upregulated in resistant cells using cDNA microarray analysis. We demonstrated that TSP‐1 increases the expression of matrix metalloproteinases through integrin signaling and promotes tumor invasion in both PC‐9‐OR and H1975‐OR, and that epithelial‐to‐mesenchymal transition (EMT) was involved in H1975‐OR. Afatinib plus CBDCA and PEM reversed TSP‐1‐induced invasion ability and EMT changes in resistant cells. In PC‐9‐OR xenograft mouse models (five female Balb/c‐Nude mice in each group), combination therapy strongly inhibited tumor growth compared with afatinib monotherapy (5 mg/kg, orally, five times per week) or CBDCA (75 mg/kg, intraperitoneally, one time per week) + PEM (100 mg/kg, intraperitoneally, one time per week) over a 28‐day period. These results suggest that the combination of afatinib plus CBDCA and PEM, which effectively suppresses TSP‐1 expression, may be a promising option in EGFR‐mutated NSCLC patients after the acquisition of osimertinib resistance.

Introduction: A neurotrophic tropomyosin receptor kinase (NTRK)‐tyrosine kinase inhibitor (TKI) has shown dramatic efficacy against malignant tumors harboring an NTRK fusion gene. However, almost all tumors eventually acquire resistance to NTRK‐TKIs. Method: To investigate the mechanism of resistance to NTRK‐TKIs, we established cells resistant to three types of NTRK‐TKIs (larotrectinib, entrectinib, and selitrectinib) using KM12 colon cancer cells with a TPM3‐NTRK1 rearrangement. Result: Overexpression of 3‐hydroxy‐3‐methylglutaryl‐CoA synthase 2 (HMGCS2) was observed in three resistant cells (KM12‐LR, KM12‐ER, and KM12‐SR) by microarray analysis. Lower expression of sterol regulatory element‐binding protein 2 (SREBP2) and peroxisome proliferator activated receptor α (PPARα) was found in two cells (KM12‐ER and KM12‐SR) in which HMGCS2 was overexpressed compared to the parental KM12 and KM12‐LR cells. In resistant cells, knockdown of HMGCS2 using small interfering RNA improved the sensitivity to NTRK‐TKI. Further treatment with mevalonolactone after HMGCS2 knockdown reintroduced the NTRK‐TKI resistance. In addition, simvastatin and silibinin had a synergistic effect with NTRK‐TKIs in resistant cells, and delayed tolerance was observed after sustained exposure to clinical concentrations of NTRK‐TKI and simvastatin in KM12 cells. In xenograft mouse models, combination treatment with entrectinib and simvastatin reduced resistant tumor growth compared with entrectinib alone. Conclusion: These results suggest that HMGCS2 overexpression induces resistance to NTRK‐TKIs via the mevalonate pathway in colon cancer cells. Statin inhibition of the mevalonate pathway may be useful for overcoming this mechanistic resistance.