Immunohistochemistry of cases with t(6;14)(p21.1;q32.3).

(A) Hematoxylin and eosin (H&E) section of a lymph node biopsy of the index case (Table 1, case 1), showing a diffuse infiltrate of large neoplastic B cells including centroblasts and some immunoblasts (original magnification × 400). (B) Same section as A stained with antibody to cyclin D3, showing the majority of the tumor cells with strong nuclear positivity (original magnification × 400). (C) H&E section of case 5 (original magnification × 100), showing background parotid gland and extranodal marginal zone B-cell lymphoma of MALT type. (D) Cyclin D3 staining of a focal area of large B-cell transformation in a background of parotid gland and low-grade extranodal marginal zone B-cell lymphoma of MALT type. Note salivary gland duct epithelium without cyclin D3 staining (original magnification × 200). (E) Same section as D stained with antibody to cyclin D3, showing focus of large neoplastic B cells with nuclear staining (original magnification × 300). (F) Cytospin of cells in the peripheral blood of case 3 stained with antibody to cyclin D3, showing intense nuclear staining of virtually all cells (original magnification × 400). (G) H&E section of bone marrow biopsy (Table 1, case 3), showing infiltrate of small B cells (original magnification × 400). (H) Same section of bone marrow stained with antibody to cyclin D3, showing intense nuclear staining of the small neoplastic B cells (original magnification × 400).