44
ICCS 2011
P8
“Indolent” T-Lymphoblastic Proliferation Involving
Bone Marrow? A Diffcult Diagnostic Dilemma.
Jennifer Crow
1
, Patrick Buckley
1
, Jon Gockerman
2
,
Anand Lagoo
1
1
Department of Pathology, Duke University Medical
Center, Durham, NC, USA,
2
Department of Medicine,
Duke University Medical Center, Durham, NC, USA
A 63 year old gentleman, previously in perfect health,
developed severe anemia and mild thrombocytopenia
following a lingering “cold” and upper respiratory
symptoms lasting several weeks. Joint and muscle
pains had developed during this time, but fever, chills
or weight loss were absent. Chest, abdomen, pelvic
CT scan was negative. Flow cytometric examination
of the bone marrow at another institution showed 10%
“blasts” based on CD45 and side scatter features and
expression of CD5, CD7, CD10, CD13, CD34, and
TdT, leading to a diagnosis of T-Acute Lymphoblastic
Leukemia. The patient declined chemotherapy and
was treated with blood transfusion, antibiotics and
steroids (prednisone 100mg). Over the next four
weeks his blood counts improved to just below normal
values and steroids were tapered off. Repeat bone
marrow examination showed a distinct population
of blasts, constituting 17% of nucleated cells (by
fow cytometry) and expressing cytoplasmic CD3
and surface CD5, CD7, CD13, CD34, CD38, CD117
(partial), CD123, HLA-DR, and TdT. No dysplasia was
seen in the normocellular marrow. Molecular studies
did not show clonal IgH or T-cell receptor gene
rearrangement and there was no evidence of EBV
infection. The patient remained clinically well without
further treatment. This is the frst description of an
indolent T-lymphoblastic proliferation involving the
bone marrow, although similar proliferations forming
mediastinal masses have been rarely described in the
literature. Awareness of this possibility draws attention
to a diffcult diagnostic dilemma and emphasizes the
need for careful clinical correlation.
POSTER ABSTRACTS