Implications of cancer staging uncertainties in radiation therapy decisions.
BACKGROUND
Radiation therapy (RT) for cancer is a critical medical procedure that occurs in a complex environment involving numerous health professionals, hardware, software, and equipment. Uncertainties and potential incidents can lead to inappropriate administration of radiation to patients, with sometimes catastrophic consequences such as premature death or appreciably impaired quality of life. The authors evaluate the impact of incorrectly staging (i.e., estimation of extent of cancer) breast cancer patients and resulting inappropriate treatment decisions.


METHODS
The authors employ analytic and simulation methods in an influence-diagram framework to estimate the probability of incorrect staging and treatment decisions. As inputs, they use a combination of literature information on the accuracy and precision of pathology and tests as well as expert judgment. Sensitivity and value-of-information analyses are conducted to identify important uncertainties.


CONCLUSIONS
The authors find a small but nontrivial probability that breast cancer patients will be incorrectly staged and thus may be subjected to inappropriate treatment. Results are sensitive to a number of variables, and some routinely used tests for metastasis have very limited information value. This work has implications for the methods used in cancer staging, and the methods are generalizable for quantitative risk assessment of treatment errors.
Lee
Robert C
RC
University of Calgary, Alberta Cancer Board, Department of Community Health Science, Canada. rclee@ucalgary.ca
Ekaette
Edidiong
E
Kelly
Karie-Lynn
KL
Craighead
Peter
P
Newcomb
Chris
C
Dunscombe
Peter
P
D001943:Breast Neoplasms / Q000473:pathology* / Q000532:radiotherapy*; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D009362:Neoplasm Metastasis / Q000175:diagnosis; D009367:Neoplasm Staging; D010818:Practice Patterns, Physicians'; D035501:Uncertainty