OBJECTIVES

To evaluate the prognostic significance of extratumoral structural abnormalities associated with malignant nonspiculate and noncalcified masses (NSNCMs) detected on mammography.

METHODS

Data from 354 breast cancer patients with mammographically detected NSNCMs between December 2017 and December 2018 were retrospectively analyzed. Cox regression analysis was performed to assess the impact of mammographic findings, particularly extratumoral structural abnormalities such as parenchymal and trabecular signs, on progression-free survival (PFS). Additionally, Kaplan-Meier survival curves were used for risk stratification.

RESULTS

The median follow-up period was 74 months (range: 10-83 months). Disease progression occurred in 122 patients (34.5%). Cox regression analysis revealed that among the mammographic features, the extratumoral contraction sign [hazard ratio (HR) = 2.56, 95% confidence interval (CI): 1.60-4.09, P < 0.001] and the extratumoral parallel sign (HR = 2.71, 95% CI: 1.57-4.70, P < 0.001) were independent predictors of NSNCM progression, demonstrating strong prognostic performance. In contrast, tumor signs did not show significant predictive value. Kaplan-Meier analysis further confirmed that these two extratumoral features effectively stratified the risk of progression in patients with malignant NSNCMs. Additionally, lymph node metastasis (HR = 2.37, 95% CI: 1.64-3.42, < 0.001) and histological grade (HR = 2.03, 95% CI: 1.05-3.92, = 0.036) were also identified as independent predictors of disease progression.

CONCLUSIONS

Specific extratumoral structural abnormalities and their subclassifications on mammography are independent prognostic indicators in breast cancer patients with malignant NSNCMs. These findings provide an important basis for personalized treatment strategies in clinical practice.