Impact of visceral adipose tissue on compliance of adjuvant chemotherapy and relapse-free survival after gastrectomy for gastric cancer: A propensity score matching analysis.

BACKGROUND & AIMS: It has been reported that skeletal muscle mass loss during adjuvant chemotherapy and preoperative reduced skeletal muscle mass are associated with discontinuation of adjuvant chemotherapy. However, the relationship between visceral fat mass and compliance has not yet been investigated. In this study, we clarified the impact of low preoperative visceral fat mass on compliance and relapse-free survival (RFS) in gastric cancer patients.

METHODS

This was a retrospective cohort study of consecutive patients with gastric cancer who underwent radical gastrectomy for pathological stages II and III, and who received postoperative S-1 adjuvant chemotherapy between April 2008 and April 2017. Treatment failure was defined as discontinuation of adjuvant chemotherapy within 1 year. Visceral fat mass was measured preoperatively at the umbilical level on computed tomography, which was divided by height (m to obtain the visceral adipose tissue index (VAI). Patients with a VAI below the median cut-off value were categorized as low-VAI, while those above the cut-off value were classified as high-VAI. We compared the treatment failure rate and RFS in the low-VAI and high-VAI groups after adjusting for group differences with propensity score matching. In addition, risk factors related to treatment failure and poor prognostic factors for RFS were analyzed in multivariate analyses that included all cases.

RESULTS

Among all 263 patients, treatment failure and recurrence were observed in 44 patients (16.7%) and 90 patients (34.2%), respectively. The median follow-up period was 52 months. After propensity matching, there were 101 patients in both low -and high-VAI groups. Treatment failure rate was higher (P = 0.037) and RFS was worse (P = 0.025) in the low-VAI group. In multivariate analyses, low-VAI was an independent risk factor associated with treatment failure (odds ratio (OR): 2.360, 95% CI: 1.120-5.000, P = 0.025), and was a poor prognostic factor for RFS (hazards ratio (HR):1.652, 95% CI: 1.057-2.582, P = 0.028).

CONCLUSIONS

Preoperative low visceral fat mass was an independent risk factor for poor compliance with adjuvant chemotherapy and a poor prognostic factor for RFS after radical gastrectomy in gastric cancer patients. Preoperative evaluation using body composition may be useful for post-treatment and prognosis prediction.