A retrospective study of preoperative malnutrition based on the Controlling Nutritional Status score as an associated marker for short-term outcomes after open and minimally invasive esophagectomy for esophageal cancer

Purpose: Preoperative malnutrition is a significant risk factor for post-esophagectomy morbidity. The Controlling Nutritional Status (CONUT) is an index used to assess nutritional status, and it has been suggested to predict post-esophagectomy morbidity. However, the difference in the predictive value of CONUT in estimating morbidities between open esophagectomy (OE) and minimally invasive esophagectomy (MIE) has not yet been elucidated.

Methods: This study included patients who underwent a three-incision esophagectomy for esophageal cancer between April 2005 and August 2021. The patients were further divided into two groups according to their preoperative CONUT scores: normal and light malnutrition and moderate and severe malnutrition. Short-term outcomes between these groups were retrospectively compared in the OE and MIE groups.

Results: A total of 674 patients who underwent OE (296) and MIE (378) were analyzed. Moreover, 32 patients of the OE group and 16 of the MIE group were classified as having moderate and severe malnutrition, respectively. Moderate and severe malnutrition was significantly associated with a low body mass index, poor performance status, poor American Society of Anesthesiologists physical status, advanced cancer stage, and frequent preoperative treatment. These patients also experienced significantly more frequent morbidities of grade ≥ IIIb according to the Clavien-Dindo classification (CDc), respiratory, and cardiovascular morbidities after OE. Moreover, moderate and severe malnutrition in CONUT was an independent risk factor for morbidity of CDc ≥ IIIb (odds ratio [OR] vs. normal and light malnutrition = 3.38; 95% confidence interval [CI], 1.225-9.332; p = 0.019), respiratory (OR = 3.00; 95% CI, 1.161-7.736; p = 0.023), and cardiovascular morbidities (OR = 3.66; 95% CI, 1.068-12.55; p = 0.039) after OE. Meanwhile, moderate and severe malnutrition in CONUT did not increase the incidence of postoperative morbidities after MIE.

Conclusion: Preoperative malnutrition in CONUT reflects various disadvantageous clinical factors and could be a predictor of worse short-term outcomes after OE, but it has no value in MIE. The low invasiveness of MIE might reduce the effect of preoperative malnutrition on worse short-term outcomes.