Correlation of MRI features and the expression of immunohistochemistry in mucinous breast carcinoma

Objective: To investigate the MRI features in correlation with the expression of immunohistochemistry in mucinous breast carcinoma. Methods: MRI and the expression of immunohistochemistry of 35 patients with mucinous breast carcinoma confirmed by histopathology were analyzed retrospectively. Results: Of 22 pure and 13 mixed mucinous breast carcinoma, 22 presented as masses, 6 as non-mass, and 7 as nodules. The tumor was T₁ hypointense (24), isointense (9), and heterogeneously hyperintense (2). On fat-saturated T₂-weighted images, 15 were homogeneously and 20 were heterogeneously hyperintense. Dynamic contrast enhancement show typical rim enhancement in 11 cases with wash-in (9), wash-out (9), and plateau (17) patterns of time-signal intensity curves. The tumors were positive for ER (32/35, 91.43%), PR (24/35, 68.57%), HER-2 (10/35, 28.57%), and Ki-67 (22/35, 62.86%). Pure tumors had higherpositive rates of ER and PR whereas mixed tumors had higher positive rates of HER-2 and Ki-67. ER and PR were correlated with contrast enhancement; HER-2 with maximum lesion diameter and shape; Ki-67 with time-signal intensity curve pattern and lymphatic metastasis. Conclusion: MRI features correlate with the expression of immunohistochemistry in mucinous breast carcinoma. (authors)