Performance of contrast-enhanced cone-beam breast CT to predict nipple-areolar complex involvement in early-stage breast cancer.

[OBJECTIVES] To evaluate the diagnostic performance of preoperative contrast-enhanced cone-beam breast CT (CE-CBBCT) and identify significant predictors of nipple-areolar complex (NAC) involvement in early-stage breast cancer patients.

[MATERIALS AND METHODS] This retrospective study included 641 breast cancer cases from 631 patients at Sun Yat-sen University Cancer Center (2019.3-2021.3). From these, 182 cases were selected after one-by-one matching with the NAC involvement group using the propensity score matching method. Two radiologists independently assessed CE-CBBCT imaging factors in 182 cases. Diagnostic performance indices were analyzed, and predictors of NAC involvement in breast cancer were identified using logistic regression analyses.

[RESULTS] The 182 matched cases were females with a median age of 50 (interquartile range, 44-55; range, 25-81 years). Interobserver agreement regarding CBBCT prediction by two radiologists was relatively substantial (κ = 0.730). The accuracy of radiologists in predicting NAC involvement in CE-CBBCT was 83.52% (152/182), with a sensitivity of 96.70% (88/91), specificity of 70.33% (64/91), negative predictive value of 95.52% (64/67), and positive predictive value (PPV) of 76.52% (88/115). On CE-CBBCT, asymmetric NAC enhancement (odds ratio, 5.279; p = 0.001) and TNE (tumor-nipple enhancement) within 2 cm of the NAC (odds ratio, 4.184; p = 0.02) were significant predictors of NAC involvement. When asymmetric NAC enhancement and TNE extending to the NAC were present, the PPV was 82.35% (56/68).

[CONCLUSIONS] CE-CBBCT is a safe and non-invasive modality with comparably high accuracy for the preoperative diagnosis of NAC involvement. Asymmetric NAC enhancement and TNE within 2 cm of the NAC performed well in predicting NAC involvement.

[KEY POINTS] Question Several imaging modalities have been studied to preoperatively evaluate NAC involvement, but CE-CBBCT's performance was unknown. Findings CE-CBBCT showed high accuracy in diagnosing NAC involvement. Asymmetric NAC enhancement and tumor-nipple enhancement within 2 cm of the NAC were independent predictors of NAC involvement. Clinical relevance CE-CBBCT can serve as a safe, non-invasive modality to diagnose NAC involvement preoperatively and help to identify candidates for nipple-sparing mastectomy.