Case 98

Submitting Author: Behdad, Amir, MD
Institution: University of Michigan
Additional authors:Lauren Smith, MD
Session: B Lymphoblastic Leukemia/Lymphoma

HISTORY

59-year-old female with history of high-grade serous carcinoma of the ovary

(diagnosed three years before); treated with surgery and cytotoxic chemotherapy. Patient presented with bruising. CBC showed pancytopenia and circulating blasts concerning for acute leukemia.

DETAILS

0.9 cm right posterior iliac crest bone marrow aspirate and core biopsy.

A 500-cell differential count of the bone marrow touch preparation revealed 94% blasts; characterized by increased nuclear:cytoplasmic ratio, fine chromatin, prominent nucleoli,

and scant blue/agranular cytoplasm. Background hematopoiesis was nearly absent.

IMMUNOHISTOCHEMISTRY AND FLOW CYTOMETRY

Flow cytometry showed approximately 87% progenitors with immunophenotype consistent with B-lymphoblasts expressing CD19, CD22 (dim) CD34, CD38, CD45 (dim), and TdT. CD10 was negative.

CYTOGENETIC FINDINGS

Cytogenetic studies showed 42~45,XX,add(1p),add(1q),add(2q),add(3q),del(5q),-7,add(10q),

del(11q),add(13p),add(15q),add(16q),-17,-18,-18,-20,+2~5mar,inc[cp10].

FISH studies revealed no rearrangement of MLL(11q23) but amplification was present.

INTERESTING FEATURES

New data support the existence of therapy-related precursor B-acute lymphoblastic

leukemia. In a study by Tang, et al. the authors suggest that cases with abnormalities including hypodiploidy with loss of chromosomes 5, 7, and 17, as reported in this case, are likely to be therapy-related and have a poor prognosis.

PROPOSED DIAGNOSIS

B lymphoblastic leukemia (B-ALL)

CONSENSUS DIAGNOSIS

Therapy-related myeloid neoplasm, mixed phenotype acute leukemia (myeloid/B)