The abstract is now available on Pubmed at:
http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract
The study results indicate that the benefit of primary excision in metastatic breast cancer is only apparent when the only mets are bone mets.
I remember that a few years ago some oncs were hesitant to excise (not only because they thought it would not change the outcome as noted in the study) but also due to the observation that while primary tumors initiate local growth factors they also appear to generate antiangiogenesis agents acting remotely whose effect may be to slow the spread of mets.
I don't know if this theory has been confirmed later on.