THYMIDINE KINASE - THE FUTURE IN BREAST-CANCER PROGNOSIS

The ability to precisely describe tumour aggressiveness in human breas t cancer is inadequate. Current prognostic indicators, although useful , cannot accurately predict tumour behavior. As a result, multivariate analyses are required to obtain any significant value from a wide ran ge of prognostic indicators. Prognostic indications are generally dete rmined from the primary tumour, but real prognostic value is dependent upon the activity of potentially metastatic lesions. We present in th is paper evidence for the use of thymidine kinase, an enzyme indicativ e of cellular proliferation, as a tumour marker with individual progno stic value. It has been previously established that thymidine kinase l evels in both tumours and sera of patients with breast cancer have bee n shown in clinical studies to be positively correlated with tumour st age. The monitoring of serial serum samples has also proven to be of p rognostic value in predicting response to therapy. Measurements of thy midine kinase levels in primary tumours have demonstrated utility as a predictor of tumour recurrence. We propose that the development of a more accurate method of measuring thymidine kinase activity may aid si gnificantly in the management of breast cancer, while eliminating the current detection problems of radiolabeling assay systems. This can be done by the inclusion of an immunologically based detection system.