The effect of needle gauge and local anaesthetic on the diagnostic accuracy of breast fine-needle aspiration cytology

Aims: The value of breast fine needle aspiration cytology (FNAC) is well es tablished. This prospective study evaluates the effects of local anaestheti c (LA) and different gauge needles on the diagnostic accuracy of breast FNA C. Methods: Aspirates were obtained from 59 consecutive excised breast tumours (51 malignant, eight benign) using green (21-G) and blue-hub (23-G) needle s, both before and after infiltration of LA at the aspiration site. Results: There was good agreement for the cytological diagnosis of each tum our when compared by needle size (kappa = 0.85) and the presence of LA (kap pa = 0.77). Diagnostic sensitivity ranged from 88 to 92%. None of the diffe rences were statistically significant. In addition LA appeared to have no e ffect upon the cytological grading of breast carcinomas (chi(2) = 1.98, df 3, P = 0.58). Discussion: The use of the smaller gauge blue-hub needle or LA does not app ear to affect adversely the diagnostic accuracy of breast FNAC, Whether usi ng LA or the blue needle routinely in the breast clinic will have an effect upon the discomfort experienced during FNAC remains to be proven.