In the wake of accusations of conflict of interest stemming from their relationship to breast implant manufactures, two Harvard Medical School researchers have resigned from the nation's largest study of the effects of implants on women's health.

Professor of Medicine Peter H. Schur and Dr. Matthew Liang, both physicians at Brigham and Women's Hospital, have worked as consultants for lawyers representing corporations producing breast implants.

The industry is now facing billions of dollars worth of legal suits from 8,000 women charging the silicone implants damaged their health.

The two doctors announced their resignation December 20 after acknowledging their ties to implant makers, according to Dr. Charles Hennekens, the director of the part of the Women's Health Cohort Study that is investigating breast implants.

The Cohort Study surveys 450,000 female nurses and other health professionals, whose data is used by researchers in various smaller studies. The implant study centers on the three percent of the participants who have breast implants.

Schur and Liang were the principal rheumatologists in the implant study.

This is the second run-in the two doctors have had with a medical ethics probe. Their resignations occur just one month after a similar conflict-of-interest issue arose from a medical journal article the doctors co-authored defending breast implants.

An investigation is currently under-way into a possible conflict of interest regarding that article, which appeared in Arthritis and Rheumatism, a journal which their edits. Allegedly, both doctors were consultants at the time they wrote the article, which was published in February.

Since Schur started his consulting last October, he has made about $30,000 critiquing medical reports, reviewing patient records and testifying in trials for four law firms. Liang's earnings were not available.

Still, Hennekens said there was no reason to suspect ulterior motives behind the doctors' research.

"Our agreement with both is based far more on the perception of how the results of the studies might be viewed, rather than any reality," Hennekens said late last month. "We are not accusing them of anything. This was bad judgment more than anything."

With their resignations, the two doctors have also agreed to stop consulting for the law firms, officials at Brigham and Women's Hospital said last month.

According to Michelle Scarlatelli, spokesperson for Brigham and Women's, the hospital will formally investigate conflict-of-interest issues raised by the incident.

Neither Schur nor Liang will comment publicly during the investigation, Scarlatelli said last month.

Questionable Funding

The research project itself is funded by a major breast implant manufacturer, casting doubt on the study's objectivity.