This patient has had a previous liver transplant for biliray atresia, splenectomy, and has been on tacrolimus since 1998. Never has has rejection issues. PET scan (not shown) demonstrated FDG avid lymph nodes above and below the diaphragm.
Appearances in the spine are consistent with lymphoma, although other metastatic disease could have similar appearances.
Histology of a cervical lymph node biopsy.
The lymph node is partially effaced by an atypical lymphoid infiltrate, comprising large cellular nodules separated by thin bands of hyalinized stroma. These nodules contain sheets of large atypical lymphoid cells with rounded to irregular nuclei and one to three large eosinophilic nucleoli. The cells have minimal pale eosinophilic cytoplasm. Admixed lymphocytes, histiocytes and sparse plasma cells are noted. Eosinophils are not seen and discrete granulomas are not identified. No transgression beyond the lymph node capsule is found.
Immunohistochemical studies have been performed. The large atypical lymphoid cells are strongly positive for CD20, Pax-5, CD45, CD30 and EBER-ISH. They are negative for EMA, ALK, CD15, CD79a, and Cyclin D1. The Ki-67 proliferative index in the large cells is approximately 95%.
The admixed small lymphocytes are reactive T cells (CD3 and CD5 positive) and there are a few admixed macrophages showing paranuclear dot - like pattern of staining for CD15. The atypical lymphoid population is CD10 negative, bcl-6 positive, and MUM1 positive.
DIAGNOSIS: Right cervical lymph node - monomorphic post transplant lymphoproliferative disorder, diffuse large B cell lymphoma type, with partial nodal involvement.