Impact of Diabetes on Pathologic Response to Multimodality Therapy for Esophageal Cancer

The incidence of esophageal cancer has increased faster than that of most cancers. Evidence from other malignant neoplasms suggests that diabetic patients have a worse response to multimodality therapy. We hypothesized that diabetic patients with esophageal cancer will have a decreased response to neoadjuvant chemotherapy and radiation therapy compared with nondiabetic patients.

A retrospective study of The Society of Thoracic Surgeons General Thoracic Surgery Database identified all patients who had an esophagectomy after neoadjuvant therapy for esophageal cancer between 2012 and 2019. Patients were compared on the basis of the presence of diabetes. A pathologic complete response (pCR) was defined as ypT0 N0. The χ² and Wilcoxon rank sum tests were used to compare patients' demographic and clinical characteristics between those with and those without diabetes. Multivariable logistic regression was used to evaluate the predictors of response to neoadjuvant therapy.

Of the 9171 patients who met inclusion criteria, 2011 (22%) patients were diabetic and 7160 (78%) patients were nondiabetic. Patients with diabetes were older, more likely to be male, and more likely to have all comorbidities. Univariate analysis revealed that diabetic patients were less likely to have pCR (16% vs 18%; P = .026). Although multivariable analysis showed a trend toward diabetic patients' having lower odds of achieving pCR, diabetes was not independently associated with pCR (odds ratio, 0.89; 95% CI, 0.78-1.01; P = .075).

Diabetic patients may be less likely than nondiabetic patients to achieve pCR after neoadjuvant treatment of esophageal cancer. This suggests the need for further exploration as diabetic patients with esophageal cancer can potentially benefit from different treatment paradigms compared with their nondiabetic counterparts.