Secondary sarcopenia is defined as a decrease in muscle mass due to disease or malnutrition. Several studies have reported that secondary sarcopenia is an indicator of postoperative recurrence. We hypothesized that there is a correlation between the effect of immune checkpoint inhibitors (ICIs) and sarcopenia. We retrospectively analyzed 38 patients with advanced non-small cell lung cancer (NSCLC) who were treated with ICIs between February 2016 and April 2018. Patients were divided into two groups according to the change rate of the psoas major muscle area (PMMA) at the L2–L3 position and investigated the correlation between the change rate of the PMMA and the efficacy of ICIs was investigated. The objective response and disease control rates were lower in patients with sarcopenia than in those without sarcopenia. Patients with sarcopenia exhibited a significantly shorter median progression-free survival (PFS) than non-sarcopenia patients. Moreover, focusing on good Eastern Cooperative Oncology Group performance status patients, sarcopenia patients showed a shorter PFS than non-sarcopenia patients. Patients with sarcopenia are associated with poor outcomes for immunotherapy among those with advanced NSCLC, based on retrospective analysis. Further research is needed to validate the clinical biomarkers involved in ICI responders.

Treatment with immune checkpoint inhibitors has shown efficacy against a variety of cancer types. The effects of nivolumab and pembrolizumab on lung cancer have been reported, and further therapeutic advances are ongoing. The side effects of immune checkpoint inhibitors are very different from those of conventional cytocidal anticancer drugs and molecular targeted drugs, and they involve various organs such as the digestive and respiratory organs, thyroid and pituitary glands, and skin. The generic term for such adverse events is immune-related adverse events (irAEs). They are relatively infrequent, and, if mild, treatment with immune checkpoint inhibitors can be continued with careful control. However, early detection and appropriate treatment are critical, as moderate-to-severe irAEs are associated with markedly reduced organ function and quality of life, with fatal consequences in some cases. Of these, endocrinopathies caused by immune checkpoint inhibitors are sometimes difficult to distinguish from nonspecific symptoms in patients with advanced cancer and may have serious outcomes when the diagnosis is delayed. Therefore, it is necessary to anticipate and appropriately address the onset of endocrinopathies during treatment with immune checkpoint inhibitors. Here, we present a review of endocrine disorders caused by immune checkpoint inhibitor treatment.

Osimertinib is a mutant-selective EGFR inhibitor that is effective against non-small cell lung cancer (NSCLC) in patients with the EGFR-T790M mutation, who are resistant to EGFR-tyrosine kinase inhibitors (EGFR-TKIs). However, the factors affecting response to osimertinib treatment are unknown. In this retrospective study, 27 NSCLC patients with the EGFR-T790M mutation were enrolled at five institutions in Japan. Among several parameters tested, the progression-free survival (PFS) associated with the initial EGFR-TKIs was positively correlated with the PFS after osimertinib treatment (p = 0.021). The median PFS following osimertinib treatment and the overall survival (OS) were longer in patients who responded to osimertinib than in those who did not (17.7 months versus 3.5 months, p = 0.009 and 24.2 months versus 13.5 months, p = 0.021, respectively). A multivariate analysis demonstrated that the PFS with initial EGFR-TKIs was significantly related to the PFS with osimertinib treatment (p = 0.035), whereas osimertinib response was significantly related to the PFS and OS with osimertinib treatment (p = 0.016 and p = 0.006, respectively). Our retrospective observations indicate that PFS following the initial EGFR-TKI treatment and the response rate to osimertinib might be promising predictors for effective osimertinib treatment in NSCLC patients with the EGFR-T790M mutation.

The EGFR-T790M mutation is clinically detected using re-biopsy in approximately 50% of patients with acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in advanced non-small cell lung cancer (NSCLC) who harbor EGFR mutations. However, little is known about the population of NSCLC patients who develop acquired resistance due to the T790M mutation. In this study, we focused on the emergence of the T790M mutation and analyzed patients refractory to initial EGFR-TKIs with successful re-biopsy samples. Seventy-eight advanced NSCLC patients with EGFR mutations who had successful re-biopsy samples after resistance to initial EGFR-TKI treatment were enrolled at 5 institutions in Japan. We validated the association between the emergence of the T790M mutation and their clinical profiles. Thirty-nine patients tested positive for T790M and 39 tested negative in the re-biopsy samples. The objective response rate to initial EGFR-TKIs was higher in patients with the T790M mutation than in those without the mutation (89.7% versus 51.2%, p < 0.001). Moreover, there was a significant difference in the maximal tumor shrinkage rate relative to baseline in T790M-positive tumors compared with T790M-negative tumors (42.7% versus 24.0%, p = 0.001). Multivariate analysis demonstrated that the maximum tumor shrinkage rate was a significant predictive factor for the detection of the T790M mutation (p = 0.023, odds ratio 1.03, 95% confidence interval 1.00–1.05). Our retrospective observations suggested that the maximum tumor shrinkage rate with initial EGFR-TKI treatment might be one of the promising predictive biomarkers for emerging refractory tumors with the EGFR-T790M mutation.

Background: The long overall survival (OS) observed among patients with non-small cell lung cancer (NSCLC) with high programmed death-ligand 1 (PD-L1) expression in chemoimmunotherapy (CIT) groups in previous phase III trials suggests the limited efficacy of CIT among the subgroup with ≤49% PD-L1 expression on tumor cells. Hence, sequential treatment with first-line platinum-based chemotherapy followed by second-line immune checkpoint inhibitor treatment (SEQ) is an option. This study examined whether first-line CIT would provide better outcomes than SEQ in patients with advanced NSCLC with ≤49% PD-L1 expression. Methods: This retrospective study evaluated patients with untreated NSCLC who received first-line CIT or SEQ at nine hospitals in Japan. OS, progression-free survival (PFS), PFS-2 (the time from first-line treatment to progression to second-line treatment or death), and other related outcomes were evaluated between the CIT and SEQ groups. Results: Among the 305 enrolled patients, 234 eligible patients were analyzed: 165 in the CIT group and 69 in the SEQ group. The COX proportional hazards model suggested a significant interaction between PD-L1 expression and OS (p = 0.006). OS in the CIT group was significantly longer than that in the SEQ group in the 1–49% PD-L1 expression subgroup but not in the <1% PD-L1 expression subgroup. Among the subgroup with 1–49% PD-L1 expression, the CIT group exhibited longer median PFS than the SEQ group (CIT: 9.3 months (95% CI: 6.7–14.8) vs. SEQ:5.5 months (95% CI: 4.5–6.1); p < 0.001), while the median PFS in the CIT group was not statistically longer than the median PFS-2 in the SEQ group (p = 0.586). There was no significant difference between the median PFS in the CIT and SEQ groups among the <1% PD-L1 expression subgroup (p = 0.883); the median PFS-2 in the SEQ group was significantly longer than the median PFS in the CIT group (10.5 months (95% CI: 5.9–15.3) vs. 6.4 months (95% CI: 4.9–7.5); p = 0.024). Conclusions: CIT is recommended for patients with NSCLC with 1–49% PD-L1 expression because it significantly improved OS and PFS compared to SEQ. CIT had limited benefits in patients with <1% PD-L1 expression, and the median PFS-2 in the SEQ group was significantly longer than the median PFS in the CIT group. These findings will help physicians select the most suitable treatment option for patients with NSCLC, considering PD-L1 expressions.