Short-term recall for 'probably benign' mammographic lesions detected in a three yearly screening programme

The outcome of short-term recall for the follow-up of 131 screen detected 'probably benign' non-palpable mammographic lesions is presented. Patients were selected for short-term recall after attending a dedicated assessment clinic and underwent repeat ipsilateral mammography 1 year later. Interval progression in the mammographic appearance prompted excision biopsy, whereas no change led to discharge back to the normal screening protocol. Of 35,671 asymptomatic women screened between 1988 and 1992, 1762 (5%) attended an assessment clinic. Subsequently, 131 women (7% assessed, 0.4% screened) were placed on short-term recall and were reviewed between 1989 and 1993 (age range 50-67 years). The 'probably benign' lesions were: calcifications (91 cases, 69%); circumscribed density (18 cases, 14%); parenchymal deformity/stellate density (13 cases, 10%); and asymmetric breast tissue (9 cases, 7%). 128/131 women attended for short-term recall (compliance 98%). Five from 128 were subject to excision biopsy with a yield of three invasive carcinomas and two ductal carcinomas in-situ. The positive predictive values for malignancy were: overall 'probably benign' lesions (PPV 3.9%); calcifications (PPV 3.3%); circumscribed density (PPV 0%); parenchymal deformity/stellate density (PPV 15.4%); and asymmetric breast tissue (PPV 0%). The largest carcinoma measured 15 mm and none of the tumours demonstrated vascular invasion or axillary metastases placing them in a favourable prognostic group. The results suggest that short-term recall is a reasonable management option for a small number of women with 'probably benign' calcifications. Parenchymal deformity and stellate densities should probably not be managed by this approach and require excision after initial assessment. Circumscribed densities and asymmetric breast tissue can be safely discharged following assessment.