RT Journal
A1 Deville C, Ben-Josef E, Vapiwala N
T1 RAdiation therapy modalities for prostate cancer
JF JAMA
JO JAMA
YR 2012
FD August 1
VO 308
IS 5
SP 450
OP 450
DO 10.1001/jama.2012.8110
UL http://dx.doi.org/10.1001/jama.2012.8110
AB 
To the Editor: The analysis by Dr Sheets and colleagues1 on the morbidity of prostate cancer patients treated with new radiation treatments has serious flaws. The subgroup treated with proton therapy was comprised of a demographically homogenous cohort from California treated at a single institution. This center has previously reported on nearly twice as many patients (N = 1255), with lower rates of serious gastrointestinal toxicity (<1% acutely; 1% in 5-year follow-up)2 than the 17.8 events per 100 person-years for gastrointestinal morbidity reported in the study. Other institutions have similarly reported much lower rates of clinically relevant grade 2 and 3 gastrointestinal toxicity.3- 4 The authors of this study based gastrointestinal morbidity on diagnoses and procedure codes, but that is misleading when a screening colonoscopy may be counted. Patients receiving proton therapy may be more likely to undergo routine screening procedures; this is supported by a trend toward increased gastrointestinal diagnosis and procedures in the proton therapy group at baseline.