Reviewer's report 
 A descriptive study of variables associated with obtaining nipple aspirate fluid in a cohort of Title: 
non-lactating women 
 1  2 June 2006 Version: Date: 
 Edward Sauter Reviewer: 
Reviewer's report: 
General 
The authors report a descriptive study of 3043 women in whom nipple aspiration was attempted by Otto Sartorious, one of the pioneers in the intraductal evaluation of the breast, and found that the ability to obtain nipple aspirate fluid (NAF) was related to age, being married, history of pregnancy, tranquilizer use and 
history of endocrine problems. Interestingly, after age adjustment, OCP use did not increase and 
postmenopausal did not decrease NAF yield, but HRT use did decrease yield. A major strength of the paper 
is the sample size. I do have some questions which I would like the authors to consider. 
Major compulsory revisions 
Based on the first sentence under Materials and Methods, â €œâ €¦Dr Otto Sartorius, who attempted NAF 
collection on 3043 women.â € it would appear that the initial cohort was 3043. The authors later state that 
women with breast cancer or women diagnosed with breast cancer within six months of their initial clinic 
visit were excluded. This would suggest that the population analyzed for this paper would be a subset of 
3043. However, under results, the authors state that â €œFluid was obtained from 43% of women 
(1314/3043),â € which would suggest that the actual number of women, before excluding those with breast 
cancer, was more than 3043. Please clarify. 
Since the authors indicate that exogenous estrogen use was not a significant determinant of ability to obtain 
fluid, yet younger age was (in which estrogen and progesterone are generally at higher circulating levels than in postmenopausal women), please speculate on the scientific reasons for the apparent paradox 
between exogenous vs endogenous female hormone effects on NAF yield. 
In the current report, the authors report a success rate of NAF collection of 43%. In a 1973 paper (Jama 
224: 825-27), Dr. Sartorius reported that â €œFor example, fluid was found in the breast aspirates of 
three-fourths of one series of 200 women who came to the clinic. The women ranged in age from 15-87 
years, and the breasts of older women contained less fluid.â € And a bit later, using oxytocin, â €œThis 
work is still experimental, buy already we find it gives almost double the yield of fluid and cellsâ €¦ We are 
now getting 90-95% cell yields.â € It would be helpful to reconcile the differences in success reported by 
Dr. Sartorius in the earlier publication with the present report, and clarify if the current cohort includes 
women who received preNAF oxytoxin. If it does, should these women be excluded? 
An important question which needs to be addressed is whether the findings in the current report can be 
generalized. The finding reported are based on the use of a device developed by Dr. Sartorius in which he 
was the sole NAF collector, as I understand it. There are many other devices which have been developed 
and different NAF collection techniques. Others investigators have reported higher NAF collection success. 
It would be appreciated if the authors could address each of the following points (why different success 
rates, influence of device, influence of technique, and influence of person performing the NAF collection). 
Minor essential revisions 
It would appear that the reference style is not that of BMC. 
 Unable to decide on acceptance or rejection until the authors have responded to the major What next?: 
compulsory revisions 
 An article of limited interest Level of interest: 
 Acceptable Quality of written English: 
 Yes Statistical review: 
Declaration of competing interests: 
I declare I have no competing interests