"New guidelines issued by three leading cancer organizations suggest that more breast cancer patients should consider radiation therapy after a mastectomy.    Overall the guidelines say theres enough evidence to show radiation treatment after a mastectomy decreases the risk of breast cancer recurrence and that even women with smaller tumors and three or fewer lymph nodes involved can benefit from the therapy.    The new guidelines say there is clear evidence that the benefit of postmastectomy radiation therapy extends to women with limited lymph node involvement said Dr. Stephen Edge. He is vice president for health care outcomes and policy at Roswell Park Cancer Institute in Buffalo N.Y. Edge was cochair of the panel that developed the new guidelines.    One radiation treatment expert welcomed the updated recommendations.    The guideline is timely said Dr. Janna Andrews an attending physician in radiation medicine at Norwell Health Cancer Institute in Lake Success N.Y. The field of postmastectomy radiation is changing. Its always up for discussion now as to who needs postmastectomy radiation therapy.    The new guidelines help clarify what used to be a gray area Andrews explained. In the past if a woman had a small tumor less than  centimeters and not more than three or four positive lymph nodes many doctors would say she does not need postmastectomy radiation therapy she said.    The guidelines dont offer a single formula for which patients need radiation therapy Edge noted. But they do focus on the group of women for whom there is the most debate about the value of radiation.    There is a great deal of controversy about whether women with one two or three lymph nodes with cancer have sufficient risk to warrant radiation he said. For women with four or more lymph nodes involved everyone would recommend radiation.    The guidelines also strongly support input from all specialists who treat breast cancer in making the decision about radiation treatment. That typically includes the surgeon radiation physician and an oncologist.    Doctors need to weigh the risks and benefits Edge added. Side effects can include redness of the skin swelling and skin breakdown severe enough to compromise future breast reconstruction he explained.    Edge said that doctors need to consider patients individually. For instance he explained a woman  who has microscopic involvement in a single lymph node and an estrogenreceptor positive cancer would be very different from a yearold who has three lymph nodes involved and socalled triplenegative breast cancer. The younger woman he said would typically be advised to get radiation.    The older woman because her risk is lower should have a discussion with her doctor to decide if the benefit outweighs the risk Edge noted.    Andrews said that one takehome message for patients is to expect the surgeon to have consulted with the radiation oncologist and others on her team. If a womans doctor tells her she does not need radiation after a mastectomy the woman should be told why and she should ask if the radiation oncologist weighed in on the decision.    Edge was a panel representative from the American Society of Clinical Oncology which created the guidelines along with the American Society for Radiation Oncology and the Society of Surgical Oncology.    All three groups published the guidelines online this week in their respective journals the Journal of Clinical Oncology Practical Radiation Oncology and the Annals of Surgical Oncology.  More information  To learn more about radiation in breast cancer treatment visit BreastCancer.org.  SOURCES Stephen Edge M.D. vice president healthcare outcomes and policy Roswell Park Cancer Institute Buffalo N.Y. Janna Andrews M.D. attending physician radiation medicine Northwell Health Cancer Institute Lake Success N.Y. and assistant clinical professor HofstraNorthwell School of Medicine Hempstead N.Y. Sept.   Journal of Clinical Oncology Practical Radiation Oncology Annals of Surgical Oncology online"