Molecular markers in testicular germ cell tumors - Objects of clinical research or close to becoming clinical tools?

The aim of this short review is to critically evaluate hitherto investigate d molecular markers for testicular germ cell tumors. Molecular parameters h ave been clinically established as diagnostic and prognostic markers for a number of tumors; this has not yet been achieved for germ cell tumors. Ther e are interesting prospects, however. Studies on the ribonucleoprotein telo merase, for example, have demonstrated a correlation between enzyme activit y and chemotherapeutic drug sensitivity. Moreover, innovative treatment app roaches target this reverse transcriptase via telomerase antisense RNA. Ano ther potential diagnostic marker is the detection of circulating tumor cell s, which correlated with an increased relapse Fate in initial studies. Ther e are also interesting possibilities for the germ-cell-tumor-specific isoch romosome [i(12)p], which is helpful in the differential diagnosis of medias tinal masses. Here initial studies demonstrated a correlation between the c opy number and resistance against chemotherapeutic drugs. Without prospecti ve studies to validate data obtained thus far, neither these nor other para meters can be assessed as diagnostic and prognostic factors. Irrespective o f their immediate clinical applicability, however, investigations on molecu lar alterations in testicular germ cell tumors will become the basis for a molecular-diagnostically oriented subclassification of tumors as well as fo r novel therapeutic approaches.