Chromosome 1 abnormalities in cervical carcinoma.

Abnormalities of chromosome 1 have been reported in a number of solid tumors and hematologic malignancies, indicating that this is a frequent event in neoplasia. Here we report our observations on aberrations of chromosome 1 in malignancies of the uterine cervix. Tumor material obtained from 148 patients with invasive carcinoma of the cervix and two cases of carcinoma in situ (CIS) was analyzed on direct preparations by G-banding. The results showed abnormalities of chromosome 1 to be one of the most common karyotypic changes, with 95% of the patients showing rearrangements of this chromosome. These changes were never seen as the sole abnormality but were always found in association with other chromosomal aberrations. Numerical rearrangements were present in 54% of the cases, with losses of unaltered chromosome 1 predominating. Consistent marker chromosomes included deletions of chromosome 1 at bands q32, p34, q42, p32, and p22, isochromosomes of both the "p" and "q" arms and translocations, particularly on the long arm. Specific regions on both arms of chromosome 1 (1p11-p13 and 1q21-q32) were preferentially overrepresented in changes involving this chromosome. Certain breakpoints were nonrandomly involved in the structural changes, particularly band 1q32 breaks occurring at this site in 88 instances. The presence of chromosome 1 aberrations in the two cases of CIS suggests that rearrangements of this chromosome are not always a secondary change contributing to the progression of the cancer, but also may represent an early cytogenetic event as in neuroblastoma, some leukemias, and myeloproliferative disorders.