Reviewer's report 
 A study of 0.5 Tesla dedicated magnetic resonance imaging for the detection of breast cancer Title: 
in young, high risk women 
 1  15 December 2005 Version: Date: 
 Bruce Kimler Reviewer: 
Reviewer's report: 
General 
There are two major points that the authors which to make: 1) That medium strength 0.5 tesla MRI is suitable for screening for breast cancer in high risk women based on its ability to detect a tumor not detected by mammography. 
2. The use of quantitative risk assessment for enrollment into a surveillance study. 
The first point is made with the successful detection of a tumor. While this study is not a comparison 
of the utility of 0.5 T to standard 1.5 T MRI (or higher strength magnets) which has been reported, 
the experiment succeeds with an N of 1. Likewise unanswered is whether high strength MRI might 
not have detected additional lesions. But as a feasibility study, the data are adequate. 
The second point is clouded by loose writing and by some missing information concerning 
methodology. In the Abstract (page 3; para 2; line 4) and in Methods (page 7; para 1; last line) the 
authors state that participants had a certain risk (based on standard models) and/or a known 
mutation in BRCA1 or BRCA2. But if this were indeed the basis for selection, then it would 
substantiate the "quantitative risk assessment" claim. Rather, it would be similar to the Kreige (2004) 
study which included mutation carriers and which employed a lower limit of 15% lifetime risk (which 
is certainly a quantitative risk assessment) for study eligibility but which these authors discount in 
making their claim to be the first to do so. Next, the authors state (page 7; para 1; line 2) that subjects were "consecutively recruited". What 
does this mean? If it is truly consecutive 30 subjects who met the initial requirements (negative 
mammogram and dense breast noted on the prior report), then there is no selection. If the review of 
mammograms did exclude potential subjects, then they are not consecutive. Lastly, potential subjects had their quantitative risk modeled and only those with >3.5% 5-year risk were eligibile. If 
the whole point of this is to demonstrate the use of quantitative risk assessment for selection into a 
study, it would seem pertinent to mention the efficiency of screening. How many potential subjects (negative mammograms and dense breasts) were excluded? How many (consecutive?) subjects 
were considered to arrive at the 30? Even here, the assumption must be made that no potential 
subject declined enrollment even though she was eligible. With this information omitted, the 
contention of using risk assessment for selection for a study can not be substantiated. 
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Major Compulsory Revisions (that the author must respond to before a decision on publication can 
be reached) 
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Minor Essential Revisions (such as missing labels on figures, or the wrong use of a term, which the 
author can be trusted to correct) 
Page 4; para 2; last line: Replace surveillance with screening. It may just be semantics but I think of 
surveillance as an ongoing series of examinations over time; while screening is a one-time 
evaluation which is what was done here. 
Page 7; para 1; lines 5 and 10: Seems to be disagreement over the minimum interval allowed 
between previous mammography and enrollment. 3 or 6 months? Also, page 8, last paragraph. 
Page 17; Authors contributions: Did JHS "perform"the MRI? Or was she responsible for reading and 
interpretation of theMRI? As well as confirming the negative mammograms and characterization of 
"dense breast"? 
Figure 2B: It would be helpful to have an arrow pointing to teh mammographically visible lesion, 
similar to what is done for MRI images. 
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Discretionary Revisions (which the author can choose to ignore) 
 Accept after discretionary revisions What next?: 
 An article whose findings are important to those with closely related research Level of interest: 
interests 
 Acceptable Quality of written English: 
 No Statistical review: 
Declaration of competing interests: 
I declare that I have no competing interests