632. CAN CARDIOPULMONARY EXERCISE TESTING PREDICT NEOADJUVANT CHEMOTHERAPY TOXICITY IN OESOPHAGEAL ADENOCARCINOMA PATIENTS?

Abstract Background Cardiopulmonary exercise testing (CPET) is a method of assessing cardiopulmonary fitness. In the context of surgery, it is used to risk-stratify patients, allowing targeted prehabilitation to optimise comorbidities and fitness prior to surgery, and triage patients to the appropriate level of care after the operation. Various CPET-derived variables have been shown to be associated with short- and long-term outcomes after various surgery. In patients post-oesophagectomy, these variables are predictive of long-term survival. This study aimed to assess the use of this tool to predict neoadjuvant chemotherapy (NAC) related complications in patients receiving neoadjuvant FLOT prior to oesophagectomy. Methods All patients who underwent routine CPET during the staging process prior to NAC with FLOT and oesophagectomy in a single high-volume centre between September 2018 and January 2023 were included. Data were extracted from the unit’s contemporaneously maintained database. The Mann-Whitney U test was used to compare CPET variables in patients who completed NAC with FLOT fully versus those who did not finish NAC with FLOT due to acute chemotherapy toxicities. Results There were 129 patients who received neoadjuvant FLOT and had routine CPET performed during the defined study period. Six of those patients (4.7%) did not complete neoadjuvant chemotherapy due to acute chemotherapy toxicities but progressed to surgery. The median anaerobic threshold, VO2 peak, and VE/VCO2 among those who completed NAC were 14.2 ml/kg/min, 20.3 ml/kg/min, and 28, respectively, compared to 13.4 ml/kg/min, 19.7 ml/kg/min, and 31 in those who did not complete NAC (p=0.595, p=0.695, and p=0.160, respectively). Conclusion Although patients who received all four cycles of NAC with FLOT prior to oesophagectomy demonstrated CPET values indicating better base-line fitness than those who had to discontinue NAC due to acute chemotherapy toxicity, these differences did not reach the level of statistical significance. This study, therefore, did not demonstrate any predictive value of CPET in assessing the risk of incomplete NAC treatment prior to oesophagectomy.