Abstract
455
Background: Systemic therapy is a critical part of the management of locally advanced pancreatic cancer (LAPC) due to the risk of distant failure. In the clinic, anecdotal evidence suggests that maintaining dose intensity of chemotherapy is more challenging after prior chemoradiotherapy (CRT). We thus evaluated whether treatment or patient factors limit the amount of systemic therapy received in LAPC patients receiving CRT. Methods: Following IRB approval, we retrospectively reviewed all patients diagnosed with LAPC undergoing CRT between 2006 and 2012. Exclusion criteria included receipt of non-gemcitabine chemotherapy or chemotherapy prior to CRT. Patient and treatment factors were evaluated for their relationship to total gemcitabine dose received during CRT and within the first three months post-CRT. Statistical analysis was performed using regression models. Results: A total of 76 patients met the inclusion criteria with a median age of 69 (range 44-89) and a median follow-up of 13.2 months (range 3-68). The median gemcitabine dose received during CRT was 3,000 mg/m2 of a planned 3,600 mg/m2 and post-CRT was 5000 mg/m2 of a planned 9,000 mg/m2. Patients receiving a higher percentage of the desired chemotherapy dose during CRT received a lower percentage of desired chemotherapy dose post-CRT (p<0.01). Patients who underwent subsequent surgical resection (p<0.01) or received a higher radiation dose (p=0.03) were more likely to have received a higher total post-CRT chemotherapy dose. There were no variables correlated to chemotherapy dose received during CRT. Conclusions: Our analysis suggests that chemotherapy dosing during CRT rather than radiation dose impacts subsequent gemcitabine dose intensity. As a number of different CRT regimens are utilized in practice, this finding warrants further confirmation in a larger database.
