Related Experiment Video
Updated: Aug 4, 2025
Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns
Published on: August 30, 2013
Assessment of malignant risk stratification for microcalcifications interpreted as "amorphous" morphology on
Dajung Kim1, Jieun Kim1, Hyun Kyung Jung1
1Department of Radiology, Inje University Haeundae Paik Hospital, Busan, Republic of Korea.
Purpose:
To investigate the malignant risk stratification of microcalcifications interpreted as amorphous morphology on mammography according to the coexistence of punctate microcalcifications based on the 5th edition of the Breast Imaging Reporting and Data System.
Method:
Between March 2013 and September 2020, 367 microcalcifications interpreted as amorphous morphology on mammography with surgical biopsies were included. The amorphous microcalcifications were classified into a predominantly punctate group (A, <50% of amorphous), a predominantly amorphous group (B, >50% of amorphous), and an only amorphous group (C, 100% of amorphous). The distribution was classified into diffuse, regional, grouped, and linear/segmental. The reference standard was the pathology. The positive predictive values (PPV) were calculated and compared using the Chi-square's test or Fisher's exact test and Kruskal-Wallis test.
Results:
The overall PPV of microcalcifications interpreted as having an amorphous morphology was 5.2%. The PPV across groups significantly increased in proportion to the amorphous morphology, with 1.0% in group A, 5.6% in group B, and 23.3% in group C (p <.001). Furthermore, the PPV between group A and groups B plus C (10.1%) and groups A plus B (2.8%) and group C were significantly different (p <.001). The PPV of distribution was 0% for diffuse, 4.9% for regional, 5.0% for grouped, and 11.1% for linear/segmental distributions, without statistical significance.
Conclusions:
Pure amorphous microcalcifications are suitable for category 4B. However, when they coexist with punctate morphology, the malignant risk decreases suitable for category 4A or lower. When amorphous microcalcifications coexist with a predominantly punctate morphology, follow-up should be considered.
Insights
Amorphous microcalcifications on mammograms have varying malignant risks. Purely amorphous types may indicate higher risk (category 4B), while those with punctate features suggest lower risk (category 4A or less).
Area of Science:
- Radiology
- Oncology
- Pathology
Background:
- Mammographic microcalcifications are key indicators in breast cancer screening.
- Amorphous microcalcifications present a challenge in risk stratification.
- The Breast Imaging Reporting and Data System (BI-RADS) provides a framework for classifying mammographic findings.
Purpose of the Study:
- To assess the malignant risk of amorphous microcalcifications based on the presence of punctate microcalcifications.
- To stratify risk using the 5th edition of BI-RADS criteria.
Main Methods:
- Retrospective analysis of 367 mammographic microcalcifications with amorphous morphology and subsequent surgical biopsies.
- Classification of microcalcifications into predominantly punctate, predominantly amorphous, and only amorphous groups.
- Calculation and comparison of positive predictive values (PPVs) using statistical tests.
Main Results:
- The overall PPV for amorphous microcalcifications was 5.2%.
- PPV increased significantly with the proportion of amorphous morphology: 1.0% (punctate-predominant), 5.6% (amorphous-predominant), and 23.3% (purely amorphous).
- Distribution patterns did not show statistically significant differences in PPV.
Conclusions:
- Purely amorphous microcalcifications can be categorized as BI-RADS 4B.
- Coexistence with punctate morphology reduces malignant risk, suggesting BI-RADS 4A or lower.
- Amorphous microcalcifications with predominantly punctate features warrant consideration for follow-up.
