flow cytometric dna ploidy analysis in haemato-lymphoid neoplasms: an analysis of 132 cases

Background: fxcycletm violet (fcv) based flow cytometric (fcm) dna ploidy analysis is a rapid and simple tool that can substantiate in characterizing the biological behaviour across the spectrum of haematological malignancies and correlates with cytogenetic studies.materials and methods: in this prospective study, we performed simultaneous immunophenotyping with fcv based on ploidy analysis in n=132 consecutive new samples, comprising n=110 samples of haemato-lymphoid neoplasms, including acute leukemias (n=67, 60.9%), cml with myeloid blast crisis (n=1, 0.9%), mds with excess blasts (n=2, 1.8%), mature b cell/ t cell neoplasms (n=37, 33.7%), multiple myeloma (n=3, 2.7%) along with n=22 normal samples. the fcm dna data was compared with corresponding conventional karyotyping results, wherever available.results: in fcm ploidy analysis (n=110), the overall dna index (di) ranged from 0.81 to 2.17 and s-phase fraction (spf) from 0.1-31.6%. diploidy was seen in n = 90 (81.8%), low-hyperdiploidy in n = 10 (9.1%), highhyperdiploidy in n = 7 (6.4%) with one case each (0.9% each) having near-tetraploidy, high-hypodiploidy and low-hypodiploidy. the di of all viable cell populations in normal samples ranged from 0.96-1.05. conventional karyotyping was performed in n=76/110 cases (70%) with n= 11/76 (15%) culture failures. the modal chromosome number ranged from 45 to 63. a concordance of 95.4% (n=62/65) was noted with corresponding fcm di.conclusion: fcv-based ploidy is a sensitive technique that provides complementary information and ascertains a strong correlation with conventional cytogenetics across all haemato-lymphoid neoplasms. it can detect aneuploidy in all b-all and myeloma cases, even in hemodiluted samples with cytogenetic culture failure; supplement the diagnoses of erythroleukemia, and provide a useful screen for a higher grade lymph node disease in lymphoma cases with spf > 3%.