Focal Radiation Therapy Dose Escalation Improves Overall Survival in Locally Advanced Pancreatic Cancer Patients Receiving Induction Chemotherapy and Consolidative Chemoradiation

Journal Article · Tue Mar 15 00:00:00 EDT 2016 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2015.12.003· OSTI ID:22645127

Krishnan, Sunil ^[1]; Chadha, Awalpreet S. ^[1]; Suh, Yelin ^[2]; Chen, Hsiang-Chun ^[3]; Rao, Arvind ^[4]; Das, Prajnan; Minsky, Bruce D.; Mahmood, Usama; Delclos, Marc E. ^[1]; Sawakuchi, Gabriel O. ^[2]; Beddar, Sam ^[2]; Katz, Matthew H.; Fleming, Jason B. ^[5]; Javle, Milind M.; Varadhachary, Gauri R.; Wolff, Robert A. ^[6]; Crane, Christopher H. ^[1]

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1. Department of Radiation Oncology, The University of Texas, Houston, Texas (United States)
2. Department of Radiation Physics, The University of Texas, Houston, Texas (United States)
3. Department of Biostatistics, MD Anderson Cancer Center, Houston, Texas (United States)
4. Department of Bioinformatics and Computational Biology, MD Anderson Cancer Center, Houston, Texas (United States)
5. Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)
6. Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

Purpose: To review outcomes of locally advanced pancreatic cancer (LAPC) patients treated with dose-escalated intensity modulated radiation therapy (IMRT) with curative intent. Methods and Materials: A total of 200 patients with LAPC were treated with induction chemotherapy followed by chemoradiation between 2006 and 2014. Of these, 47 (24%) having tumors >1 cm from the luminal organs were selected for dose-escalated IMRT (biologically effective dose [BED] >70 Gy) using a simultaneous integrated boost technique, inspiration breath hold, and computed tomographic image guidance. Fractionation was optimized for coverage of gross tumor and luminal organ sparing. A 2- to 5-mm margin around the gross tumor volume was treated using a simultaneous integrated boost with a microscopic dose. Overall survival (OS), recurrence-free survival (RFS), local-regional and distant RFS, and time to local-regional and distant recurrence, calculated from start of chemoradiation, were the outcomes of interest. Results: Median radiation dose was 50.4 Gy (BED = 59.47 Gy) with a concurrent capecitabine-based (86%) regimen. Patients who received BED >70 Gy had a superior OS (17.8 vs 15.0 months, P=.03), which was preserved throughout the follow-up period, with estimated OS rates at 2 years of 36% versus 19% and at 3 years of 31% versus 9% along with improved local-regional RFS (10.2 vs 6.2 months, P=.05) as compared with those receiving BED ≤70 Gy. Degree of gross tumor volume coverage did not seem to affect outcomes. No additional toxicity was observed in the high-dose group. Higher dose (BED) was the only predictor of improved OS on multivariate analysis. Conclusion: Radiation dose escalation during consolidative chemoradiation therapy after induction chemotherapy for LAPC patients improves OS and local-regional RFS.

• OSTI ID: 22645127
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Vol. 94, Issue 4; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
CHEMOTHERAPY
GY RANGE 10-100
INDUCTION
MULTIVARIATE ANALYSIS
NEOPLASMS
PANCREAS
PATIENTS
RADIATION DOSES
RADIOTHERAPY