(The FASEB Journal. 2008;22:898.36)
© 2008 FASEB
(The FASEB Journal. 2008;22:898.36.)
© 2008 FASEB
Atypical B-cell infiltrate in a pediatric patient: diagnostic and pathogenetic considerations
Alina Emilia Dulau Florea1,
Ira Richmond Abbott2,
Howard Ratech1,
Josefina Llena1,
Yvonne Lui3,
Joaquim Farinhas3 and
Karen Weidenheim1
1 Pathology
2 Neurosurgery
3 Neuroradiology, Montefiore Medical Center, Bronx, NY
ABSTRACT
Pediatric primary central nervous system lymphoma (PCNSL) represents1–1.5% of all PCNSL. Pediatric PCNSL are usually high grade B-cell lymphoma (30%) or anaplastic large cell lymphomas. Herein we report a 15 year-old male with a well-circumscribed, enhancing mass centered on the right thalamus with mass effect on the 3rd ventricle and obstructive hydrocephalus. Endoscopic biopsy produced only hemorrhage; repeat biopsy three months later produced multiple fragments of pink-tan soft tissue including pineal gland, grey matter, granulation tissue, choroid plexus, and a diffuse mononuclear cell infiltrate composed of a mixture of small round and large atypical lymphoid cells with irregular vesicular nuclei, 2 to 3 nucleoli attached to the nuclear membrane, and moderately abundant eosinophilic cytoplasm. The large lymphoid cells showed immunoreactivity for CD20, PAX-5, and CD79a (B-cell markers) but were negative for epithelial and germ cell markers; small T lymphocytes were also present. The lymphocytic process infiltrated brain tissue containing atypical astrocytes and large binucleated neurons. Immunoglobulin heavy chain (Ig-VDJ; B-cell) and T-cell receptor (TCR) beta and gamma gene rearrangement studies showed a monoclonal B-cell population. This atypical B-cell infiltrate with features of lymphoma may have arising in an inflammatory infiltrate accompanying a pre-existing glio-neuronal tumor.
