Fine needle aspiration cytology of the breast: factors affecting sensitivity.

At Northampton General Hospital a pathologist takes, stains and immediately reports aspirates at a fine needle aspiration clinic which is run in conjunction with a busy surgical breast clinic. The effect of various factors on the sensitivity of the technique have been quantified. Small tumour size, certain types of tumour and lesions difficult to palpate are causes of reduced sensitivity. Acellular samples had little effect on sensitivity. In this clinic trainee aspirators achieved good results early in their experience. After one year each had improved to the level of an experienced aspirator.