Analysis of Clonal Cytogenetic Abnormalities in Persistent Cytopenia: Relation of Degree of Dysplasia and Prognosis

We aimed to detect clonal cytogenetic abnormalities in persistent cytopenia by fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) to assess their relations with degree of dysplasia and prognosis. The present study is a cohort prospective study that was conducted on 40 patients with persistent pancytopenia from Ain Shams University Hematology/Oncology clinics. The selection criteria included patients with normal karyotype. Fluorescence in situ hybridization technique was applied using routine probes of MDS (LSI 5q31-q33, LSI 7q33, LSI 17p13, LSI 11q23). Molecular analysis using real time PCR was applied for detection of p53 mutation. The present study revealed 18 patients (45%) with normal cytogenetic analysis by FISH. The most common gene deformity detected is del 17p in four cases (10%), followed by del 5q31 (7.5%), del 7q31 (7.5%), and complex chromosomal abnormalities in the form of del 5q31, del 7q31 and del17p in 2 patients (5%), On the other hand, real time PCR analysis for p53 mutation revealed eight cases (20%) positive for P53 mutation, out of them, five cases (12.5%) showed heterozygous mutation and three cases showed homozygous mutation (7.5%). Notably, Patients with poor prognosis had significantly higher frequencies of TP53 mutations (50% versus 0 %, p =0.01). There was no significant association between prognosis and FISH findings. A considerable proportion of the patients with MDS exhibit chromosomal abnormalities using FISH analysis, even if they have normal karyotype. Likewise, we found that TP53 presented a significant prognostic role in patients with MDS. Thus, integrating karyotyping, FISH and PCR analysis for TP53 mutation will add value to the diagnostic workup of suspected patients as MDS.