A comparison of rapid methods including imprint cytodiagnosis for the diagnosis of breast tumours.

Rapid diagnoses were made on 510 breast lumps by three methods in sequence and the results compared with those obtained by paraffin histology.Naked-eye examination of the excised lumps correctly distinguished between benign and malignant tumours in 95.1% of cases with 23 (4.5%) false negative and two (0.4%) false positive results.Rapid imprint cytodiagnosis was correct in 96.9% of the 391 lumps imprinted with 12 (3.1%) false negatives and no false positive results. Frozen sections gave the correct diagnosis in 99.4% of the 510 cases with three (0.6%) false negative and no false positive results. The use of cytology in the diagnosis of breast tumours is discussed.