[gdpawel]

Hope

This seems to confirmed the retrospective analysis presented at the 2011 European Multidisciplinary Cancer Congress by the Karolinska Institute, Sweden that tumor hormone-receptor and HER2 status can change in breast cancer patients during the course of their disease. And because these changes can significantly influence survival and can completely change the patient's clinical management, these patients should undergo regular biopsies.

For example, they saw that 32.4% of breast cancer patients had altered ER status and 40.7% had altered PR status and 14.5% of patients change HER2 status during the course of disease. A similar pattern was seen in patients who experienced multiple consecutive relapses, 33.6% in ER status, 30.2% in PR status and 15.7% in HER2 status. Treatment options that were effective in the primary cancer might not be optimal for the relapsed/metastatic disease.

Findings published in the Annals of Oncology (2010; 21:1254-1261) showed a much higher proportion of changes in these key receptors than has been previously reported; differences between nodal tumor tissue and primary breast cancer was seen in 46.9% of patients with metastatic disease. In addition, many of the differences in expression between the primary tumor and the node were large-magnitude (>5-fold) changes.

Changes in molecular phenotype between primary and metastatic breast cancer have been recognized in phenotype analyses. The endpoints of molecular profiling (genotyping analysis) are gene expression, examining a single process (pathway) within the cell or a relatively small number of processes (pathways) to test for theoretical candidates for targeted therapy. The endpoints of functional profiling (phenotyping analysis) are expression of cell-death, both tumor cell death and tumor associated endothelial (capillary) cell-death (tumor and vascular death), and examines not only for the presence of the molecular profile but also for their functionality, for their interaction with other genes, proteins and other processes occurring within the cell, and for their actual response to anti-cancer drugs (not theoretical susceptibility).

In other words, pheotype (functional profiling) analyses, which measure biological signals rather than DNA indicators, provides clinically validated information and plays an important role in cancer drug selection. The data that support phenotype analyses is demonstrably greater and more compelling than any data currently generated from genotype analyses.

Greg