| Abstract | Objectives: Pediatric leukemias are generally characterized by recurrent genetic aberrations, which are thought to be specifically associated with diagnosis and prognosis. The aim of the study was to investigate the frequency and types of acquired chromosomal aberrations and correlation with other biological characteristics and prognostic risk factors.
Materials and methods: We retrospectively reviewed clinical features and results of cytogenetics and molecular analysis for patients younger than 18 years with newly diagnosed pediatric leukemia from January 2000 to December 2017.
Results: In an 18-year period, 98 children with pediatric leukemia were hospitalized, 47 girls (48 %) and 51 boys (52 %). We had 76 patients diagnosed with ALL (77%), 20 with AML (21%), and 2 with CML (2%). Fever, pallor, lymphadenopathy, and hepatomegaly were the four most common presenting symptoms of leukemia in children (more than 50%). Among all patients, 29% had normal karyotype while 71% had acquired numerical and/or structural chromosomal aberrations. The most frequent chromosomal aberrations in pediatric ALL were t(12;21) ETV6/RUNX1 fusion gene (27%) and hyperdiploidy (15%), both associated with prognostic favorable outcomes and B cell lineage immunophenotype. In AML subgroup, the most frequent chromosomal aberration was translocation t(8;21) with RUNX1-RUNX1T1 fusion gene (21%), slightly higher than reported in the 2008 WHO Classification. On the other hand, the frequency of 11q23 MLL-rearrangements, t(15;17) with PML-RARA fusion gene, inv(16) or del(16q), deletion -7/del(7q) was in accordance to the literature. Two patients were diagnosed with CML, Ph-positive.
Conclusion: In this study, the frequency of various acquired chromosomal aberrations as well as their correlation with clinical and biological risk factors in a group of children with newly diagnosed leukemia are similar to previously published studies at pediatric population in Europe and US. |
| Abstract (croatian) | Uvod: Pedijatrijske leukemije općenito su karakterizirane ponavljajućim genetičkim aberacijama, a za koje se smatra da su specifično povezane s dijagnozom i prognozom. Cilj istraživanja bio je ispitati učestalost i vrste stečenih kromosomskih aberacija i usporediti ih s drugim biološkim karakteristikama i prognostičkim čimbenicima rizika.
Materijali i metode: Retrospektivnim istraživanjem prikazali smo kliničku sliku i rezultate citogenetičke i molekularne analize kod pacijenata mlađih od 18 godina sa novodijagnosticiranom pedijatrijskom leukemijom u periodu od siječnja 2000. do prosinca 2017. godine.
Rezultati: U osamnestogodišnjem razdoblju leukemija je dijagnosticiranau 98 djece, 47 djevojčica (48%) i 51 dječaka (52%). Od toga 76 pacijenata imalo je dijagnozu ALL (77%), 20 AML (21%), i 2 CML (2%).Više od 50% djece imalo je četiri najčešća simptoma leukemije:vrućicu, bljedilo, limfadenopatiju i hepatomegaliju.Od svih pacijenata uredan kariotip imalo je 29% pacijenata dok je 71% imalo stečene numeričke i/ili strukturne kromosomske aberacije.Najučestalije aberacije u pedijatrijskoj ALL bile su t(12;21) s fuzijom ETV6/RUNX1 gena (27%) i hiperploidija (15%), a obje su povezane sa prognostički povoljnim ishodom i B staničnim imunofenotipom. U grupi djece sa AML najučestalija kromosomska aberacija bila je t(8;21)s fuzijom gena RUNX1/RUNXT1(21%), nešto viša nego što je objavljeno u klasifikaciji SZO 2008. S druge strane učestalost 11q23 MLL- preuređenja, t(15;17) s fuzijom PML-RARA gena, inv (16) ili del (16q), -7/del(7q) bile su u skladu s podacima iz literature. Philadelphiapozitivnu CML leukemiju imalo je dvoje djece.
Zaključak: Učestalost i raznolikost stečenih kromosomskih aberacija upedijatrijskim leukemijama iz našestudijekao i njihova povezanost s kliničkim i biološkim prognostičkim čimbenicima slična je podacima iz literature za pedijatrijsku populaciju u Europi i SAD-u. |
