Comparative safety and efficacy of single-agent chemotherapy combined with microwave ablation versus radioactive seed brachytherapy in elderly patients with advanced NSCLC: a ten-year retrospective study

Elderly patients with advanced non-small cell lung cancer (NSCLC) often have limited tolerance for standard therapies and experience reduced efficacy with lower-intensity treatments. This study evaluated the safety and efficacy of single-agent chemotherapy combined with either microwave ablation (MWA) or radioactive iodine-125 seed ablation brachytherapy (RSABT) as first-line treatments, aiming to establish personalized, high-efficacy, and low-toxicity options for this vulnerable population. We conducted a retrospective analysis of 128 untreated elderly patients with advanced NSCLC from November 2013 to November 2023. 71 patients received RSABT plus chemotherapy, while 55 underwent MWA plus chemotherapy, with single-agent pemetrexed, docetaxel, or gemcitabine initiated 5-7 days post-procedure. Overall outcomes, including time to local progression (TTLP), overall survival (OS), and progression-free survival (PFS), did not differ significantly between the RSABT and MWA groups. However, in patients with tumors ≥ 4 cm, the RSABT group demonstrated significantly longer TTLP (14 versus 8 months, <i>P</i> = 0.005) and OS (15 versus 11 months, <i>P</i> = 0.039). The MWA group exhibited higher rates of postoperative pectoralgia (58% versus 34%, <i>P</i> < 0.001) and pleural effusion (18% versus 4%, <i>P</i> = 0.013). Additionally, tumors located within 10 mm of the pleura in the MWA group were linked to increased pulmonary complications, including pneumothorax and bronchopleural fistula (odds ratio [OR] = 9.455, <i>P</i> = 0.041), whereas no such association was observed in the RSABT group (OR = 0.872, <i>P</i> = 0.79). In conclusion, combining single-agent chemotherapy with either MWA or RSABT is effective and safe for elderly patients with advanced NSCLC. RSABT demonstrated superior safety and efficacy compared to MWA for tumors ≥ 4 cm or those located within 10 mm of the pleura, making RSABT a more suitable first-line treatment option in these cases.