Radiological predictors of successful therapeutic wide local excision of ductal carcinoma in situ : findings from the Sloane project

The aim of this analysis was to ascertain whether mammographic unidimensional measurement (UDM), bidimensional product (BDP) measurement and pathological grade are helpful in predicting which patients could be offered a successful single therapeutic wide local excision (WLE) for ductal carcinoma in situ (DCIS).

The study group was 505 patients with DCIS whose mammograms showed calcification, and in whom a nonoperative diagnosis had been obtained and a WLE attempted. Mammographic calcifications were measured in two planes at 90° on the oblique view and were classified pathologically as high, low or intermediate nuclear grade. In the sample, 342 patients had a successful first WLE and 163 patients had further surgery.

A UDM <35 mm and a BDP <800 mm were associated with successful excision at first operation (69% vs 54%, P = 0.02 and 70% vs 27%, P = 0.0001, respectively). If the BBP cut-off had been applied to these cases, 16 unsuccessful WLEs would have been prevented but six successful WLEs may have been replaced by mastectomies. The histological nuclear grade did not influence the chance of a successful first WLE (66%, 69% and 80% for low, intermediate and high nuclear grade, respectively). The BDP maintained significance in subgroups based on nuclear grade more frequently than UDM.

The BDP of mammographic calcification is a better predictor of successful WLE than UDM.