Waiting too long after a hysterectomy to begin radiation therapy may increase the risk of uterine cancer recurrence, according to a new study from researchers at Henry Ford Hospital in Detroit.
The study shows that for patients with uterine cancer not receiving chemotherapy, tumors were more likely to return if radiation therapy was delayed nine weeks or longer following surgery, with only 43 percent having relapse-free survival after five years.
By comparison, patients starting radiation treatment soon after surgery had a five-year relapse-free survival of 90 percent.
"Our data suggests that a shorter interval of time between hysterectomy and start of radiation treatment may be beneficial for patients," says lead author Mohamed Elshaikh, M.D., senior staff physician in the Department of Radiation Oncology at Henry Ford Hospital.
Study results will be presented Monday, October 30 at the 54th Annual Meeting of the American Society for Radiation Oncology (ASTRO) in Boston.
Endometrial cancers mainly arise from the tissue lining the uterus. They are the most common gynecologic cancers in the US, with more than 43,000 women diagnosed and an estimated 7,950 dying from the disease in 2010, according to the National Cancer Institute.
A total hysterectomy (surgical removal of the uterus) is the most common approach for treatment of endometrial cancers.
To assess the impact of time between hysterectomy and the start of radiation treatment on tumor recurrence, Dr. Elshaikh and his colleagues conducted a retrospective study of patients who underwent surgery for uterine cancer between 1988 and 2010.
Of the 1,450 Henry Ford patients reviewed with stage I-III uterine cancer, 308 received radiation therapy without chemotherapy after hysterectomy with at least one year follow-up. The median age for patients was 65 and the median follow-up was six years.
About 75 percent of the study group started radiation therapy less than nine weeks after surgery, while the others began treatment nine weeks or more after surgery.
Among the study group, there were 43 cases where the cancer returned. Tumor recurrence was significantly associated with treatment delay of nine weeks or longer.