Umberto Veronesi, an Italian oncologist, former health minister and senator widely respected for his work on preventing and treating breast cancer, has died, his foundation said. He was 90.

Veronesi's eponymous foundation announced his death late Tuesday, saying his final message was one of encouragement "to continue, because the world needs science and reason."

Veronesi was internationally recognized as one of the fathers of cancer research. He advocated conservative treatment of breast cancer and his research over three decades is credited with helping hundreds of thousands of women each year to receive curative surgery, preserving the breast.

His work on cancer research led him to vegetarianism and fasting, subjects of several books he wrote.

He also promoted a conservative approach to treating melanoma, adopted by the World Health Organization.

Umberto Veronesi M.D. Knight Grand Cross OMRI was also a politician, internationally known for his contributions on prevention and treatment of breast cancer throughout a career spanning over fifty years.

Veronesi was born in Milan. He obtained his degree in medicine from the University of Milan in 1952, and dedicated his professional life to the study and treatment of cancer.

After spending brief periods in England and France, he joined the Italian Cancer Institute in Milan as a volunteer. Veronesi was the founder of breast-conserving surgery in breast cancer treatment with the invention of the technique of quadrantectomy which challenged the dominant paradigm among surgeons that cancer could only be treated with aggressive surgery. He supported and promoted scientific research aimed at improving conservative surgical techniques, including sentinel lymph node biopsy, which resulted in axillary dissection in breast cancer with clinically negative lymph nodes no longer being performed. He also contributed to breast cancer prevention conducting studies on tamoxifen and retinoids and verifying their capabilities to prevent the formation of carcinoma. He was an activist in anti-tobacco campaigns. In 1994 he founded the European Institute of Oncology, which he directed until his death. He was appointed President of the Scientific Committee of the Italy-USA Foundation in 2010. In 2009, through his foundation (Fondazione Veronesi), he started the project "Science for Peace", in order to promote peaceful relations through scientific development.