Letter to the Editor: EGFR-TKIs Combined with Allogeneic CD8+ NKT Cell Immunotherapy to Treat Patients with Advanced EGFR-Mutated Lung Cancer

Dear Editor,

We would like to comment on the publication “EGFR-TKIs Combined with Allogeneic CD8+ NKT Cell Immunotherapy to Treat Patients with Advanced EGFR-Mutated Lung Cancer. ¹ ” This trial looked at the combination of donor CD8+ NKT immunotherapy with gefitinib for the treatment of advanced or metastatic EGFR-mutated non-small cell lung cancer. A total of 19 patients with common EGFR mutations (exon 19 deletion or L858R mutation) were randomized into two groups: gefitinib alone and gefitinib+NKT. The results showed that the gefitinib/NKT group had considerably longer progression-free survival (PFS), with a median PFS of 12 months compared to 7 months in the gefitinib alone group. Serum carcinoembryonic antigen (CEA) levels were also controlled in the NKT group. However, the study found a greater frequency of grade 3 clinical side events in the gefitinib/NKT group (64% vs 39%), including abnormal liver function in 73% of patients, raising concerns regarding the safety of these combination therapy. The study's methodology includes possible flaws, such as a limited sample size of only 19 patients, limiting the findings’ generalizability and statistical power.

Furthermore, the large disparities in cohort sizes (8 patients in the gefitinib group vs 11 patients in the gefitinib/NKT group) may have influenced the findings. To corroborate these findings, future research should include bigger multicenter studies with a broader patient population and longer follow-up periods to investigate long-term outcomes and toxicity. Innovative techniques could include investigating the appropriate dose and timing of NKT therapy in combination with gefitinib, as well as combining other immune checkpoint inhibitors to maximize therapeutic benefit while reducing side effects. Collaborations on tailored immunotherapy techniques based on tumour microenvironment analysis may improve therapeutic efficacy for NSCLC patients with EGFR mutations.