Objective: To investigate expressions of E-cadherin (E-cad), p120catenin (p120), 34βE12 in invasive lobular carcinomas of the breast and their roles of diagnoses.
Methods: The 81 cases of ILC, including 67 cases of pure type and 14 cases of ductal-lobular mixed type, which had been diagnosed in our department were collected and immunohistochemistry of E-cad, p120 and 34βE12 were performed. All the cases were diagnosed again according to morphology and immunophenotypes (MaxVision method), and difference of diagnoses and expressions of the three indexes were analysed.
Results: Sixty four of 81 cases were permantly diagnosed of ILC. In the 61 cases of pure type, 54 cases displayed E-cad negative and p120 cytoplastic positive, 1 case displayed E-cad negative and p120 atypical positive, 3 cases displayed E-cad membrane positive and p120 cytoplastic positive, and 3 cases displayed both atypical positive. Fifty two of 61 cases displayed 34βE12 positive. The 3 cases of mixed type displayed p120 cytoplastic positive, and 2 cases displayed E-cad negative and 1 case displayed atypical positive. All the 3 cases displayed 34βE12 positive.
Conclusions: The diagnosis of ILC is one of the most difficult problems in breast pathology, and combination of E-cad and p120 immunostaining is an effective method for assistance. It needs further studies for invasive ductal carcinomas with morphological features of lobular carcinomas.