Three unrelated clonal cell lines identified by cytogenetic analysis in a patient with acute myeloid leukemia (AML) evolved from a pre-existing polycythemia vera (PV)
Purpose: Study the dynamics of transformation of MPDs into AML by molecular (PCR/FISH),cytogenetic techniques, morphology & flow cytometry.
Methods: A peripheral blood specimen from a 58 year old male with a long history of polycythemia vera (PV)was received for leukemia work up by morphology, flow cytometry & cytogenetics. FISH testing is in progress.
Results: Flow cytometry analysis showed involvement by acute myeloid leukemia (AML). The blasts were positive for CD34, CD13 (dim), CD33 & GPHA, suggesting an acute eythroleukemia (AML-M6) Because of his known history of PV, molecular study for JAK V617F mutation was performed, which was positive. Cytogenetic studies showed three unrelated abnormal clones:
45,XY,add(5)(q13),-17[9]/
61-64,XY,+1,+2,+6,+13,add(14)(p11.2),+15,+18,+19,+19,+8-11mar[cp8]/
46,XY,dup(1)(q21q42)[2]/
46,XY[1]
Conclusions: Our observations confirmed that the patient had an underlying MPD consistent with P.vera. The findings also indicate that the AML-M6 may harbor the JAK V617F mutation. Further, that the P. vera with JAK2 mutation may evolve into AML. The fact that the three unrelated cytogenetically abnormal clones coexisted, suggests that blastic transformation may not always result in a monoclonal process at a given time & that the JAK2 mutation may not always be confined within a clonal process.
Implications of FISH/PCR/cytogenetic results with clinical & hematopathologic findings will be discussed in the prognosis of MPD & transformation to AML.