Lymphoblastic lymphoma is a malignant lymphoma of precur¬sor lymphocytes. Approximately 5 to 15% of Lymphoblastic lymphomas are of B-cell lineage. Although they may occur at any age, the majority of these rare lymphomas have been described in children and young adults. These neoplasms present frequently in cervical lymph nodes, bone, or the central nervous system or as skin tumors of the scalp and face (1).
Histologically, they exhibit a diffuse growth pattern with fre¬quent mitoses (Fig. 1A,B) and a "starry sky" appearance. Capsular and interfollicular involvement of lymph nodes is characteristic. Cytologically, the tumor cells are small to intermediate in size with irregular nuclear borders, dispersed chromatin, and small nucleoli. (2).
Most B-cell lymphoblastic lymphomas are CD19, CD79a, CD10, and terminal deoxynucleotidyl transferase (TdT) posi¬tive with undetectable cytoplasmic Ig and variable expression of CD45 and CD20 (3). |