Diagnosis: ALL T-CELL SUBTYPE LEUKEMIA CUTIS (1997 Uniformed Services Dermatology Seminar, Case#14) submitted by: Richard Laws, CPT, MC, USA

History: presented with a five month history of an increasing number of asymptomatic scalp nodules. These were originally diagnosed as bug bites by his primary care physician. Two weeks before presenting to the dermatology clinic, the patient had a CBC as part of Gulf War veteran screening which revealed increased lymphocytes and the presence of blast cells.

Exam: PHYSICAL EXAM: On the scalp there were numerous 1-2 cm subcutaneous erythematous nodules with overlying partial alopecia. LABORATORY: Hct = 32, Wbc = 7.2, Neuts 9, blasts 10, lymphs 65, plts 50K HISTOPATHOLOGY: Sections demonstrated a dense, diffuse infiltrate of atypical monomorphic lymphoid cells that replaced much of the dermis and subcutaneous tissue. Immunophenotyping of cells from paraffin block revealed a T-cell population. Flow cytometry demonstrated this population to be CD2+, CD3+, CD4+, CD8+, C5+, and CD7+ as well as CD10+. These findings were consistent with the diagnosis of T-cell lymphoblastic leukemia, Group 2.