Differentiation of Pure Mucinous Carcinoma and Fibroadenoma on Ultrasound of the Breast / 中山大学学报(医学科学版)

ABSTRACT

ObjectiveTo investigate the difference of ultrasound characteristics between pure mucinous carcinoma （PMC） and fibroadenoma （FA） of the breast. MethodsUltrasound data of 50 continuous patients with breast PMC from January 2012 to January 2021 and 100 continuous patients with breast FA from June 2018 to January 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were retrospectively reviewed. The ultrasound characteristics of the two groups were evaluated according to the 2013 BI-RADS Ultrasound Atlas， and the differences in age， maximum diameter and ultrasound characteristics between the two groups were compared. ResultsThe median age of PMC patients was 47 years and that of FA patients was 33 years. The age of PMC patients was higher than that of the FA group， and the difference between the two groups of patients was statistically significant （P<0.001）. The median maximum diameter of PMC patients was 2.4 cm， which was greater than that of the FA group （1.8 cm）， and the difference was statistically significant （P=0.001）. Of the PMC， 70% （35/50） were irregular， 82% （41/50） were parallel to the skin， 92% （46/50） had no circumscribed margin， 72% （36/50） were hypoechoic， and 68% （34/50） had enhanced posterior echo. Of the FA， 69% （69/100） were oval or round， 98% （98/100） were parallel to the skin， 54% （54/100） had circumscribed margin， 98% （98/100） were hypoechoic， and 75% （75/100） had no posterior features. The differences in the above ultrasound characteristics between the PMC and FA groups were statistically significant （P<0.001， P=0.001， P<0.001， P<0.001， P<0.001）. There was no significant difference between calcifications and blood flow. ConclusionsCompared with the FA group， patients with PMC are older and the diameter of the lesions are larger. On ultrasound， the morphology and margin of most breast PMC still show the growth characteristics of invasive cancer. Meanwhile， the posterior echo of PMC is enhanced， which is a unique manifestation.