OBJECTIVETo explore the incidence and prognostic significance of chromosome 7 anomaly in acute leukemia.

METHODSConventional cytogenetic analysis of R-band was used to detect the abnormalities of chromosome 7 in 410 acute leukemia patients.

RESULTSThirty-two cases (7.8%) with abnormalities of chromosome 7, of which 19 (59.4%) had -7/7q-; 3(9.4%) had t(7;11); and the rest had other abnormalities such as der(7), +7, t(2;7), t(5;7), t(7;9), t(7;8) and dic(1;7). The incidence of -7/7q- in M0, M1 and M2 was higher than that in other subtypes of acute myeloid leukemia (AML). Twenty cases had additional cytogenetic aberrations, such as t(9;22) with -7, +8, -5. In 30 cases treated with chemotherapy, 11 cases acquired complete remission (CR) and the CR rate was lower than that for all concurrent cases of acute leukemia(36.7% vs 65.8%); the CR rate of AML with -7/7q- was lower than that of AML with normal karyotype(25% vs 55.6%). There was no difference in the CR rate between acute lymphocytic leukemia(ALL) with -7/7q- and ALL with normal chromosome (57.1% vs 77.8%), but 4 cases with -7/7q- which attained complete remission for a time relapsed early. In other 11 patients with additional chromosome 7 aberration, only 4 patients acquired CR.

CONCLUSION-7/7q- was the frequent aberration in chromosome 7 anomaly, which was often detected in M0, M1 and M2. It might be associated with the pathogenesis of acute leukemia; the patients with chromosome 7 anomaly had poorer prognosis.