ABSTRACTS – ORAL PRESENTATIONS - AMCA, spol. s r.o.

P53. SELECTED UNQUESTIONABLE ONCOLOGIC DIAGNOSIS IN CASE OF FLOW
CYTOMETRY APPLICATION
Jana Chovancová 1,2 , Olga Stehlíková 1 , Tomáš Bernard 1 , Jiří Mayer 1,2 , Michael Doubek 1,2
1
Department of Internal Medicine – Hematology and Oncology, University Hospital, Brno
and Faculty of Medicine, Masaryk University, Brno, Czech Republic
2
Central European Institute of Technology, Masaryk University, Brno, Czech Republic
The aim of our study is to show some hematological diagnosis as well as nonhematological
disorders in different stages, which were identified in our laboratory
of flow cytometry and could cause confusion from the flowcytometric point of view.
Following disorders have been selected: T-cell prolymphocytic leukemia (T-PLL), acute B
lymphoblastic leukemia (B-ALL), where the presence of pathologic cells is extremely low,
and bone marrow metastatic infiltration of rhabdomyosarcoma (RMS).
T-PLL is a rare, aggressive lymphoid malignancy with characteristic morphologic,
immunophenotypic, cytogenetic, and molecular features. However, the flow cytometric
discrimination of T-PLL from other T-cell disorders might be challenging. The case is
presented of 65-year-old man, showing the pathologic population with hyperexpression
of antigens CD5 and CD7, negative expression of cytoplasmatic TdT, surface antigen
CD3 and TCR. Thus, the whole measured phenotype is CD2 + s3 - c3 + 4 + 5 ++ 7 ++ 8 - cTdT - TCR -
(Dearden, 2012).
B-ALL is quite common leukemia in children, so detecting usually does not cause any
trouble. What could lead to make misdiagnosis is a type of relapse which presents just a
low level of blastic cells in peripheral blood (< 1 % of leukocytes) that is hardly detected
by morphology approach. Since a pathologic population is commonly CD45 negative, the
small number of blastic cells hides in the area of erythrocytes, trombocytes and debris
showing fallacious healthy results.
RMS is the most common soft tissue sarcoma in children under 15 years. The patients
typically present with a tumor mass in the head and neck region, urogenital tract or lower
extremities. Unusual massive bone marrow infiltration that could imitate hematologic
neoplasm is presented of a teenage boy, where typical phenotype CD45 - 56 ++ 57 + 90 + of
pathologic cells was found (Bozzi et al., 2008).
Flow cytometry is a well-established approach for diagnosing hematological and
lymphoid disease as well as detecting metastatic cells of some solid tumors in bone
marrow. Nevertheless, considering some rare cases results could lead to deceptive
conclusions.
Acknowledgements
This work was supported by grant MUNI/A/0723/2012.
References
Bozzi F, Collini P, Aiello A, Barzann E, Gambirasio F, Podda M, Meazza C, Ferrari A, Luksch
R.: Flow Cytometric Phenotype of Rhabdomyosarcoma Bone Marrow Metastatic Cells
and its Implication in Differential Diagnosis with Neuroblastoma – Anticancer Research
Analytical Cytometry VII 151