Chromosomal pattern in acute lymphoblastic leukaemia

Analysis of the chromosomal changes in various neoplasia is being increasingly carried out not only to evaluate its relationship with the prognosis and biological behaviour of the tumour but also for diagnostic purposes in some cases. Leukaemias are one such group of haematological malignancies which have been most extensively studied in this regard. Karyotypic analysis with Giemsa banding technique was carried out in 35 consecutive cases of Acute Lymphoblastic Leukaemia. Eighteen cases were in children (less than 15 years age) and 17 cases were in adults. M.F. ratio was 1.8:1 FAB classification of these cases showed 31 cases of L1 type and 4 cases of L2 type including one case of T-ALL. Fifteen cases (43%) had no karyotypic abnormality, 6 cases (17%) showed pseudodiploidy, one case each having (-20 + 21), t (9:22), (+ 2-6), (-6 + 8), while two cases had 6 q-.13 cases (37%) showed hyperdiploidy with 6 cases showing trisomy 8 alone, one case (+ 8 + 21), one case trisomy 18, one case + 15(r), one case trisomy 21 plus t (9:22) and one case with trisomy 21 only. Two cases showed more complex abnormalities i.e. + 2 + 8, t (13:22) and -11 + MR + Min + Min. There was one (3%) case of hypodiploidy showing monosomy 6. The above findings are in agreement with studies carried out in other countries except t (13:22) which is rather a scarcely reported abnormality.