SUSPICIOUS MICROCALCIFICATIONS ON FULL-FIELD DIGITAL MAMMOGRAPHY AND ITS CORRELATION WITH RISK OF MALIGNANCY: ASSESSMENT OF POSITIVE PREDICTIVE VALUE.

Abstract

Abstract:

Objectives:

To evaluate retrospectively the positive predictive value of suspicious microcalcifications diagnosed on full-field digital mammography (FFDM) and establish the likelihood of malignancy using stereotactic biopsy results as gold standard.

Study duration and Settings:

Retrospective study was conducted at the Department of Diagnostic Radiology, Dallah hospital, Riyadh, Saudi Arabia.  Study duration was 2.3year (January 2018-March 2020).

Material and methods:

The study included 60 female patients with microcalcification on Mammogram who underwent stereotactic guided biopsy between January 2018 and March 2020. The sample size was calculated using the WHO calculator. Non probability consecutive sampling was used for selection of patients.  Ethical approval was taken.

Patients underwent digital mammography with tomosynthesis and stereotactic biopsy. The morphology and distribution of microcalcifications was assessed on mammogram and subsequently BI-RADS (Breast Imaging-Reporting and Data System) descriptors were recorded. Finally, correlation with histopathology was performed. Data was analysed using SPSS version 24. Chi-square and Pearson’s correlation was applied. P value ≤0.05 was considered significant.

Results

Total 60 biopsies were included in this study. Mean age of women was 50years±30.1SD. There were 30(50%) women in the age group 30-40 years and 30(50%) women in the age group of 40-50 years. In mammography, microcalcification is seen in the right breast in 20(33.3%) cases and in the left breast in 38(63.3%) cases.

Of the 60 microcalcification lesions biopsied, 33 were benign and 27 were malignant, representing an overall positive predictive value of 45% for the microcalcification on mammogram  The morphologic characteristics of the suspicious  microcalcifications were as follows: amorphous in 13(22.0%) of the 60 cases, coarse heterogeneous in 14(23.3%), Pleomorphic in 25(41.6%) and linear microcalcifications in 8(13%). Among the 60 cases, the distribution of the suspicious microcalcifications was classified as grouped in 51(85%), as segmental in 8(13.3%), and as regional in 1(1.6%).

 The 22 malignant lesions consisted of 2 cases of DCIS (9.1%) and 20(90%) cases of invasive ductal carcinoma.

In our study 63% of patients with a BIRADS score of 4 to 5 had Microcalcifications associated with benign tissue.

Conclusion:

Suspicious microcalcifications (BIRADS category 4 and 5) on digital mammography had high positive correlation with histopathological findings. Appropriate screening for high risk patients leads to early diagnosis and lowers the disease progression.

Key words:

Stereotactic biopsy, FFDM, VABB, Suspicious microcalcification, DCIS, BI-RADS.