Future chemoradiation strategies in pancreatic cancer.

Department of Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
Seminars in Oncology (Impact Factor: 4.33). 09/2007; 34(4):335-46. DOI: 10.1053/j.seminoncol.2007.05.001
Source: PubMed

ABSTRACT Although not universally accepted, 5-fluorouracil (5-FU)-based chemoradiation is considered a standard treatment for patients with localized pancreatic cancer. Randomized trials have indicated that chemoradiation improves median survival of both locally advanced and resected pancreatic cancer. While the use of adjuvant chemoradiation in pancreatic cancer has been called into question since the publication of the European Study Group for Pancreatic Cancer (ESPAC)-1 trial, this study has not changed standard practice in the United States. All randomized trials investigating adjuvant chemoradiation have reported significant local as well as distant disease control limitations, making the study of novel chemoradiation and adjuvant chemotherapy important. Selected centers are investigating neoadjuvant chemoradiation in radiographically resectable patients. Advantages of neoadjuvant chemoradiation compared to postoperative therapy include increased local control, increased access to therapy, addressing the systemic disease recurrence risk without delay, and optimal patient selection for pancreaticoduodenectomy through exclusion of patients with rapidly progressive metastatic disease. In the years since it was approved for use in pancreatic cancer, gemcitabine has stood the test of time as a systemic agent but has not been widely adopted as a radiosensitzer in pancreatic cancer. Single-arm clinical trials that initially explored gemcitabine as a radiosensitzer in locally advanced pancreatic cancer demonstrated the potential for significant toxicity without dramatic improvements in efficacy. Recent strategies for improving the efficacy of chemoradiation include improved chemoradiation sensitization through the concurrent incorporation of molecular targeted agents, and the use of new radiation technology such as intensity-modulated radiotherapy (IMRT) and stereotactic radiotherapy. Herein, we discuss the relative merits of strategies that seek to improve outcome through these novel means and present recent data from novel strategies that will provide the background for future trials.

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