Postoperative chemoradiotherapy following pancreaticoduodenectomy. Impact of dose-volumetric parameters on the development of diabetes mellitus.

PURPOSE

The purpose of this research was to analyze the relationship between dose-volumetric parameters and the development of diabetes mellitus (DM) in patients treated with chemoradiotherapy (CRT) following curative resection for upper gastrointestinal (GI) cancers.

PATIENTS AND METHODS

Medical records of patients who underwent postoperative CRT following curative resection, either pancreaticoduodenectomy (PD) or pylorus preserving pancreaticoduodenectomy (PPPD) for upper GI cancers including pancreas, biliary, ampullary, and duodenal cancers, between January 2006 and December 2008 were retrospectively reviewed. A total of 42 patients who were regularly followed for at least 2 years were included for analysis. Dose-volumetric parameters such as remnant pancreatic volume, mean dose, maximum dose (Dmax), and percentage of volume receiving specific dose or more were obtained from pre- and postoperative CT scan images and treatment plan.

RESULTS

Dmax and V50 (percentage of volume receiving at least 50 Gy) were statistically significant factors for the development of DM (p = 0.013, p = 0.031, respectively). The sensitivity and specificity of Dmax was 0.875 and 0.559, with cut-off value of 51.1 Gy, respectively. V50 had sensitivity of 0.875 and specificity of 0.618 for cut-off value of 16 %. No patient-related factor other than pretreatment cerebrovascular events was associated with the development of DM. On multivariate analysis, V50 was the only factor with statistical significance (p = 0.028), whereas Dmax showed borderline significance (p = 0.079).

CONCLUSION

V50 was the only independent factor associated with the development of diabetes and may function as guideline to predict the development of DM in patients receiving CRT following curative resection.