Has the Pattern of Practice in the Prescription of Radiotherapy for the Palliation of Thoracic Symptoms Changed Between 1999 and 2006 at the Rapid Response Radiotherapy Program?
Received 15 September 2007; received in revised form 27 October 2007; accepted 30 October 2007.
Purpose
Eleven randomized controlled trials (RCT) comparing various radiotherapy (RT) schedules for locally advanced lung cancer published since 1991 found no difference in palliation of intrathoracic symptoms. The most commonly prescribed schedule by Canadian Radiation Oncologists (RO) (20 Gy in five fractions [20 Gy/5]), when first evaluated versus 10 Gy/1 in a 2002 RCT, showed a significant survival benefit. A subsequent RCT assessing 20 Gy/5 found worse survival versus 16 Gy/2. This study examines whether the RT prescription for lung cancer palliation in the Rapid Response Radiotherapy Program (RRRP) has changed over time.
Methods and Materials
Chart review was conducted for patients treated with palliative thoracic RT across three periods (1999–2006). Patient demographics, tumor, treatment, and organizational factors were analyzed descriptively. Chi-square test was used to detect differences in proportions between unordered categorical variables. Continuous variables were tested using analysis of variance. Multivariate logistic regression was used to identify independent predictors of RT schedule prescribed.
Results
A total of 117 patients received 121 courses of palliative thoracic RT. The most common dose (20 Gy/5) comprised 65% of courses in 1999, 68% in 2003, and 60% in 2005–2006 (p = 0.76). The next most common dose was 30 Gy/10 (13%). Overall, the median survival was 14.9 months, independent of RT schedule (p = 0.68). Multivariate analysis indicated palliative chemotherapy and certification year of RO were significant predictors of prescription of 20 Gy/5.
Conclusion
RT schedule for palliation of intrathoracic symptoms did not mirror the results of sequential, conflicting RCTs, suggesting that factors other than the literature influenced practice patterns in palliative thoracic RT.
∗Rapid Access Palliative Radiotherapy Program, Cross Cancer Institute, Edmonton, Alberta, Canada
†Rapid Response Radiotherapy Program, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
‡Department of Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada
Reprint requests to: Edward Chow, M.B.B.S., Ph.D., F.R.C.P.C., Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, Canada M4N 3M5. Tel: (416) 480-4998; Fax: (416) 480-6002
Presented in part in poster form at the 20th International Symposium of Supportive Care in Cancer, June 27–30, 2007, St Gallen, Switzerland.
This project was generously supported by the Michael and Karen Goldstein Cancer Research Fund. Dr. Barbera is supported by a Career Scientist Award from the Ontario Ministry of Health and Long Term Care.
ABSTRACT