Differential diagnosis of sclerosing lymphocytic lobulitis of breast in frozen section

Objective: To discuss the differential diagnosis for sclerosing lymphocytic lobulitis of breast from invasive ductal carcinoma and lymphoma in frozen section.Methods: The histopathological and immunohistochemical features of sclerosing lymphocytic lobulitis of breast were analyzed by HE staining and immunohistochemical assay.Results: The specimen was solid,yellowish-white.Frozen section examination revealed atrophy and destruction of lobules and proliferation of fibrous stroma with hyalinization.Diffusely infiltration of small round cells,which sometimes were arranged in cords or strand-like patterns,were seen in the stroma.Immunohistochemical assay showed the small round cells were positive for CD20,CD79α,CD3,CD45RO(+),but negative for CK and CK7.The Ki-67 labeling was less than 1%.Conclusion: Sclerosing lymphocytic lobulitis is a benign inflammatory lesion.This lesion is easily confused with invasive ductal carcinoma and lymphoma in frozen section.Immunohistochemical staining is helpful for differential diagnosis.