Background: The increasing use of mammography has led to a significant increase in the detection of clinically occult lesions, the majority of which prove to be benign. SFNB has been suggested as a means of expediting a diagnosis for lesions that are malignant while limiting surgical biopsies for those that are benign.
Methods: Clinically occult mammographic lesions were assessed by SFNB in 2,988 patients. Definitive histologic diagnoses were made on surgical specimens in all instances in which the cytologic diagnosis was malignant, suspicious, or atypical. Patients with benign cytology were either followed with interval mammograms or underwent surgical biopsy.
Results: Two hundred ninety-one of the 295 lesions (99%) diagnosed as cancer via SFNB were confirmed by histopathology. Twenty-two of the 22 lesions (100%) that were diagnosed as suspicious were diagnosed on histopathology as malignant. Forty-three of the 70 lesions (61%) with cytologic atypia were diagnosed on histopathology to be malignant.
Conclusions: SFNB is an accurate means of diagnosing carcinoma, but must be followed by surgical biopsy when the cytology shows atypia. For lesions diagnosed as benign by SFNB, close interval mammography is essential.