Detection of micro calcifications in breast specimen by 4-fold DIMA directmagnification radiography compared to 1.5-fold conventional magnification radiography.

The purpose of this study was to investigate the efficacy of 4-fold magnifi cation breast specimen radiography (direct magnification, DIMA) compared to conventional 1.5-fold magnification radiography in evaluating the presence or absence of carcinoma at the surgical margins by detection of microcalci fication. Methods: Fifty breast specimens with non-palpable microcalcificat ions were examined during surgical biopsy using both DIMA (4-fold) and conv entional (1.5-fold) magnification specimen radiography. The number of detec ted microcalcifications of the whole specimen, of an area of 5 mm distance to the margins and of the area of the suspicious cluster of microcalcificat ions was counted and the results compared with the histological examination as a gold standard. Results: In 50 specimen 2821 (1305 within 3 mm distanc e to the margins) microcalcifications were detected with the DIMA mammograp hy technique compared to 1608 (446) microcalcifications with the convention at technique. This increased detection rate by DIMA-magnification radiograp hy was accompanied by a decreased specificity in comparison to the conventi onal magnification radiography (33,3% DIMA versus 83,3% conventional) regar ding the evaluation of presence or absence of carcinoma at the surgical mar gins. Differentiating the microcalcifications into calcifications belonging to the suspicious cluster and those that are located outside the cluster l ed to an increase in specificity (83,3 % DIMA versus 100% conventional). Co nclusions: The efficacy of breast specimen radiography in evaluating the pr esence or absence of carcinoma at the surgical margins by detection of micr ocalcification is not improved by 4-fold magnification radiography (direct magnification, DIMA) compared to conventional 1.5-fold magnification radiog raphy due to an increase in false-positive results. Analysis of the attache ment of the microcalcifications to the cluster can improve the specificity.