Isochromosome of Chromosome 12: Clinically Useful Marker for Male Germ Cell Tumors

TLDR

The study included germ cell tumors from all primary sites and histologies. The authors propose further investigation of chromosome 12 abnormalities in male germ cell tumors. They analyzed 29 tumor specimens from 24 male patients with germ cell tumors. Isochromosome i(12p) was detected in 20 of 29 tumors across all sites and histologies, with ≥3 copies linked to higher treatment failure, suggesting it is an early, prognostically significant event in male germ cell tumors.

Abstract

Twenty-nine tumor specimens were obtained from 24 males with germ cell tumors. All primary sites and histologies were represented. An isochromosome of the short arm of chromosome 12 [i (12p)] was found in 20 specimens obtained from 16 patients, a 46,XY normal karyotype was present in seven specimens, and one specimen was a cytogenetic failure. The i(12p) was found in tumors from all primary sites and in all histologies, including a choriocarcinoma. The presence of three or more additional copies of 12p was associated with a statistically significant greater likelihood of treatment failure. With diagnostic and possibly prognostic importance in germ cell tumors in males, the high frequency of i(12p) in our series of studies and in those of others indicates that it probably occurs as a very early defect in the development of these tumors. Further studies of chromosome 12 in males with these tumors are warranted.