A cytogenetic study of children in India with acute lymphocytic leukemia: correlation with clinical data.

We studied 25 children in India with acute lymphoblastic leukemia; all of them were less than 15 years old. The karyotypes, determined with banding techniques, were correlated with clinical data. Thirteen of these patients had an adequate chromosome analysis and two others were in remission when samples were obtained. For the remaining ten, specimens were inadequate for cytogenetic analysis. Thirty-one percent of the 13 patients had a normal karyotype. The most common abnormal pattern was a hyperdiploid karyotype with greater than 50 chromosomes observed in 38% of the patients. Two patients had a Ph chromosome. Other chromosome changes, such as t(8;14), del(6), t(4;11), or t(1;19), were not seen in our series. A correlation between the karyotype and response rate and survival time was noted. Patients with a normal karyotype had a good prognosis, whereas, hyperdiploidy (greater than 50 chromosomes) and a low white blood cell count were associated with poor prognoses. Trisomy for the long arm of chromosome #1 (bands 1q25 to 1q32), which was seen in most of our patients with hyperdiploidy, also indicated a poor prognosis. Of the 25 patients, eight were from agricultural areas where they were often exposed to pesticides; there was no correlation between a history of such exposure and the karyotype of the leukemic cells.