Abstract Rationale Surgery is a driver of systemic inflammation and immune suppression, which are often poorly tolerated in elderly patients with extensive comorbidities common to thoracic oncology. Prognostic nutritional index (PNI) is a measure of nutritional and immune status and is used commonly as a preoperative measurement. Therefore, the postoperative-to-preoperative PNI ratio may serve as a marker for surgical stress. This analysis evaluates the association between PNI ratio and perioperative outcomes after robotic-assisted video-thoracoscopic (RAVTS) lobectomy. Methods A retrospective cohort study was conducted for patients who underwent RAVTS lobectomy by a single surgeon from 2015-2025. Patients with both preoperative and postoperative (within one day of surgery) albumin and lymphocyte counts were included. PNI was calculated as PNI = (10*albumin gdL) + (0.005*total lymphocyte count /mm3) preoperatively and postoperatively, and PNI ratio was calculated as postoperative PNI / preoperative PNI. Outcomes included intraoperative complications, estimated blood loss (EBL), skin-to-skin operative duration, cardiac and respiratory complications, prolonged air leak 5 days, hospital length of stay (LOS), 30-day mortality, and median overall survival time (MST). Statistical methods included Mann Whitney U, Spearman correlation, multivariable logistic regression, and Kaplan Meier. Results Of 859 total patients, 557 study patients (mean age 69.2±9.7 years; mean BMI 27.8±5.6kg) had evaluable data and were included, with a mean PNI ratio of 0.82±0.08. PNI ratio was significantly correlated with increased EBL (r=-0.196, p 0.001), skin-to-skin operative duration (r =-0.153, p 0.001), and chest tube duration (r =-0.096, p = 0.024). PNI ratio trended to be associated with hospital LOS, but this association did not reach significance (p = 0.06). PNI ratio was not significantly associated with intraoperative complications (p = 0.34), respiratory complications (p = 0.36), cardiac complications (p = 0.07), or 30-day mortality (p = 0.70). After adjusting for age, sex, BMI, pack-year history, and Charlson comorbidity index (CCI), PNI ratio was not independently associated with prolonged air leak 5 days (OR = 0.145; 95%CI=0.012-1.716; p = 0.126). For Kaplan-Meier OS analysis, a previously described cutoff PNI ratio=0.88 was utilized. However, PNI ratio was not significantly associated with MST (log-rank p-value=0.675). Conclusion PNI ratio correlated with markers of operative complexity and chest tube duration but was not an independent predictor of major outcomes following RAVTS lobectomy. Based on this analysis, PNI ratio may reflect the physiological stress imposed by surgery rather than predict major postoperative outcomes. Analyses with larger multi-institutional studies are necessary to further assess the prognostic value of PNI ratio and determine if dynamic changes in PNI later in recovery are a stronger approximation of clinical outcomes. This abstract is funded by: None
Bedard et al. (2026) studied this question.