Shota Mitsuboshi, Motoka Omata, Hiroaki Shidei, Akira Ogihara, Tamami Isaka, Masato Kanzaki
Stapler lavage cytology (SLC) is an intraoperative method used to detect malignant cells by cytologic examination of saline used to rinse the stapling device. This study evaluated the prognostic significance of positive SLC after lung cancer surgery. Of 674 patients who underwent lung cancer surgery between January 2013 and July 2019, 589 were included after excluding biopsy-only cases, clinical stage IIIB-IV disease, small-cell lung cancer, and cases with unavailable SLC results, and were classified according to SLC status. Overall survival (OS) and recurrence-free survival (RFS) comparisons showed a significantly lower 5-year survival rate in the SLC[+] group. Univariable analysis showed that older age, pleural invasion, higher pathological T and N classifications, non-adenocarcinoma histology, and SLC positivity were associated with poorer OS. Similarly, pleural invasion, higher pathological T and N classifications, non-adenocarcinoma histology, and SLC positivity were associated with poorer RFS. Notably, all five recurrences in the SLC[+] group were local recurrences. SLC positivity was associated with poor OS and RFS. These findings suggest that SLC may have prognostic value and warrant validation in larger prospective studies.