Background. To evaluate the outcomes, adverse events, and therapeutic role of Dose-Painted Intensity-Modulated Radiation Therapy (DP-IMRT) for locally advanced pancreas cancer (LAPC). Methods. Patients with LAPC were treated with induction chemotherapy ( ) and those without metastasis ( ) received DP-IMRT consisting of 45？Gy to Planning Treatment Volume 1 (PTV1) including regional lymph nodes with a concomitant boost to the PTV2 (gross tumor volume ？cm) to either 50.4？Gy ( ) or 54？Gy ( ) in 25 fractions. DP-IMRT cases were compared to three-dimensional conformal radiation therapy (3D-CRT) plans to assess the potential relationship of radiation dose to adverse events. Kaplan-Meier and Cox regression analyses were used to calculate survival probabilities. The Fisher exact test and t-test were utilized to investigate potential prognostic factors of toxicity and survival. Results. Median overall and progression-free survivals were 11.6 and 5.9 months, respectively. Local control was 90%. Post-RT CA-19-9 levels following RT were predictive of survival ( ). Grade 2 and ≥grade 3？GI toxicity were 60% and 20%, respectively. In comparison to 3D-CRT, DP-IMRT plans demonstrated significantly lower V45 values of small bowel ( ), stomach ( ), and mean liver doses ( ). Conclusions. Dose-escalated DP-IMRT offers improved local control in patients treated with induction chemotherapy for LAPC. Radiation-related morbidity appears reduced with DP-IMRT compared to 3D-CRT techniques, likely due to reduction in RT doses to organs at risk. 1. Introduction Pancreatic cancer is currently the fourth leading cause of cancer-related deaths in the United States [1]. There were an estimated 37,680 new cases in 2008 and that approximation has now risen to 43,920 for 2012 [1, 2]. Pancreatic cancer has a very poor overall survival, due in part to the fact that less than 15% of patients have resectable disease at diagnosis [3]. Furthermore, an estimated 15–50% of patients who were initially thought to have resectable cancer will be found at the time of surgery to have unresectable or metastatic disease [3], suggesting an aggressive biology of this cancer. Various modalities have been developed for the treatment of locally advanced pancreatic cancer (LAPC), including chemotherapy alone, chemotherapy followed by chemoradiotherapy, stereotactic body radiotherapy (SBRT), and combination regimens of chemoradiotherapy and SBRT [4–6]. Despite the judicious application of such treatment modalities, LAPC continues to have an extremely poor prognosis with median survival rates range between 7.9
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