Disease control in patients with non-small cell lung cancer using pemetrexed: Investigating the best treatment strategy.

BACKGROUND: Pemetrexed (PEM) is the primary chemotherapy for non-small cell lung cancer (NSCLC), showing potential for long-term disease stability in certain cases. However, studies examining disease control with PEM therapy are lacking. This study aimed to pinpoint clinical traits in patients with NSCLC responding well to PEM therapy, predict factors influencing disease control, and suggest optimal treatment approaches. METHODS: A retrospective analysis of patients with NSCLC treated with PEM was performed to compare patients who achieved disease control after treatment with those who did not. RESULTS: Of 73 patients, 56 (76.7%) achieved disease control with PEM therapy. In the disease control group, a significantly higher proportion of patients exhibited good performance status (PS) and received PEM doses without reduction after the second cycle. Multivariate analysis identified bevacizumab (Bev) noncompliance, PEM dose reduction, and thyroid transcription factor-1 (TTF-1) negativity as significant independent risk factors for disease progression during PEM therapy. Additionally, overall survival was significantly longer in the disease control group (p < 0.001). CONCLUSIONS: Our findings indicated that maintaining the dose of PEM after the second treatment cycle in patients with NSCLC, along with concurrent use of Bev and the presence of TTF-1 positivity, could enhance disease control rates and extend survival.

Investigation of response factors for monotherapy with immune checkpoint inhibitors in non-small cell lung cancer patients with PD-L1 expression <50.

BACKGROUND: Immune checkpoint inhibitor (ICI) monotherapy is currently approved for the treatment of advanced non-small cell lung cancer (NSCLC) patients with programmed death ligand-1 (PD-L1) expression ≥50%. However, the efficacy of ICI monotherapy in patients with PD-L1 expression <50% has not yet been fully elucidated. The aim of this study was to identify the clinical characteristics of NSCLC patients with PD-L1 expression <50% who respond to single-agent ICIs and factors that predict response. METHODS: Patients with advanced or recurrent NSCLC with a PD-L1 tumor proportion score (TPS) of 50% or less who received new monotherapy with an ICI between July 2012 and December 2022 were retrospectively analyzed. Patients with response were compared with those without response in the post-treatment response assessment. RESULTS: Among the 37 patients, six (16.2%) NSCLC patients in the response group responded to ICI monotherapy and had a significantly lower body mass index (BMI) (p = 0.003). Significantly more patients in the response group developed immune-related adverse events (irAEs) than in the nonresponse group (p < 0.001). Multivariate analysis identified high BMI as a significant independent risk factor predicting nonresponse to ICI monotherapy in NSCLC patients with PD-L1 < 50%. CONCLUSIONS: Among NSCLC patients with PD-L1 < 50%, those with a higher BMI were more likely to be nonresponders to ICI monotherapy. In addition, the group that responded to ICI monotherapy may have been at higher risk of developing irAEs, suggesting that careful follow-up is warranted.