B AND T LYMPHOBLASTIC LYMPHOMA/LEUKEMIA
abnormalities: Most pre-B-cell tumors are hyperdiploid. Translo-cations are common
in both B-ALL and T-ALL.
tumors are positive for terminal deoxytransferase (TdT).
lineage classification is based on
presence or absence of cytoplas-mic or surface markers, including surface
immunoglobulin (sIg) pres-ence (mature B-ALL) and cytoplasmic μ presence
(pre-BALL). The B-cell tumors almost always express B-cell molecules CD19 and
T-cell lineage: The majority of T-ALLs
stain with CD2, CD3, CD5, and CD7.
B-ALL is more common in children;
symptoms include fever, anemia, and bleeding
T-ALL often presents as a
mediastinal mass in an adolescent male
Most cases of lymphoblastic
lymphoma are T-cell neoplasms that are aggressive and rapidly progressive. Most
patients are young males with a mediastinal mass (think thymus). The leukemic
phase of lymphoblastic lymphoma is similar to T-ALL and some consider them the
same entity. Most cells are CD1+, CD2+, CD5+, and CD7+.