Original Article
CT-based assessment of visceral adiposity and outcomes for esophageal adenocarcinoma
Abstract
Background: Various methods of quantifying and correlating obesity to outcomes for patients with esophageal adenocarcinoma (EA) have been evaluated. Published data suggest that quantification of adiposity may be more accurate than body mass index (BMI) as a prognostic factor. We report our analysis of adiposity as a prognostic factor in a series of patients with EA.
Methods: This single institution retrospective review included patients with EA who underwent esophagectomy from 1994–2008. Patients with BMI <20 were excluded. Using the preoperative CT scan, the visceral (VFA), subcutaneous (SFA), and total abdominal fat (TFA) areas were calculated. Each was contoured on a Siemens Leonardo workstation at the level of the iliac crest (L4/5). The Hounsfield threshold was −30 to −130. Outcomes were analyzed using Kaplan-Meier method and log-rank analysis. Multivariate analysis (MVA) was performed using the Cox proportion hazard regression model.
Results: We identified 126 patients for the analysis. There were no statistically significant differences in overall survival or disease-free survival between groups above and below the medians for TFA, SFA, or VFA/SFA ratio. However, an increase in VFA was significantly associated with worsened OS and DFS when we further classified patients into quartiles. Patients with VFA ≥182 cm² had larger tumor size (P=0.016), fewer involved lymph nodes (P=0.047), longer operating times (P=0.032), and were more likely to be males (P=0.042).
Conclusions: Published data have demonstrated an association between treatment outcomes and degree of adiposity; our study found a correlation between VFA and OS and DFS in patients with EA. Median TFA, SFA, and VFA/SFA were not prognostic on MVA. While VFA >182 cm2 was associated with larger tumors, there were also fewer lymph nodes harvested in this group.
Methods: This single institution retrospective review included patients with EA who underwent esophagectomy from 1994–2008. Patients with BMI <20 were excluded. Using the preoperative CT scan, the visceral (VFA), subcutaneous (SFA), and total abdominal fat (TFA) areas were calculated. Each was contoured on a Siemens Leonardo workstation at the level of the iliac crest (L4/5). The Hounsfield threshold was −30 to −130. Outcomes were analyzed using Kaplan-Meier method and log-rank analysis. Multivariate analysis (MVA) was performed using the Cox proportion hazard regression model.
Results: We identified 126 patients for the analysis. There were no statistically significant differences in overall survival or disease-free survival between groups above and below the medians for TFA, SFA, or VFA/SFA ratio. However, an increase in VFA was significantly associated with worsened OS and DFS when we further classified patients into quartiles. Patients with VFA ≥182 cm² had larger tumor size (P=0.016), fewer involved lymph nodes (P=0.047), longer operating times (P=0.032), and were more likely to be males (P=0.042).
Conclusions: Published data have demonstrated an association between treatment outcomes and degree of adiposity; our study found a correlation between VFA and OS and DFS in patients with EA. Median TFA, SFA, and VFA/SFA were not prognostic on MVA. While VFA >182 cm2 was associated with larger tumors, there were also fewer lymph nodes harvested in this group.
