By Katie Riley, Arizona Health Sciences Center, July 13, 2010
A new study by University of Arizona researchers suggests that breast cancer may be a significant risk factor for developing a serious form of endometrial cancer in women age 55 or younger.
Wenxin Zheng, MD, and Setsuko K. Chambers, MD, of the Arizona Cancer Center and the UA department of obstetrics and gynecology were among an international group of scientists who participated in the research study, which partially was funded by the Arizona Cancer Center from its National Cancer Institute core grant and from a Better Than Ever pilot grant.
Results will appear in an upcoming print issue of the International Journal of Cancer and are available now on the journal's online edition.
Cancer of the endometrium – the lining inside the uterus – is the most common malignancy of the female genital tract in the U.S. Most cases respond to treatment and have a fairly good prognosis, said Zheng, who also holds a professorship in the UA department of pathology and serves as director of gynecologic pathology and molecular pathology at the UA College of Medicine.
A less common form of endometrial cancer – Type II or endometrial serous carcinoma (ESC) – tends to afflict older women and is considered more dangerous because it presents few symptoms until the cancer is advanced, he said.
In their study, the researchers found that nearly 20 percent of the 348 women they studied with Type II endometrial cancer had a prior history of breast cancer, compared to only 3 percent in a control group of 830 women with the more common form of endometrial cancer.
Among the study subjects with Type II endometrial cancer, the incidence of breast cancer was significantly higher (41 percent) in patients 55 years or younger compared with those who were older than 55 (16 percent).
The study findings may have important implications for younger women with breast cancer. These patients and their physicians may want to be vigilant about symptoms (such as abnormal bleeding) of Type II endometrial cancer, a diagnosis that otherwise is rare in younger women, Zheng said. Abnormal bleeding in younger women is most commonly found to be from non-cancerous causes.
"This frequent association of breast cancer and ESC may suggest there is some genetic-based intrinsic linkage between these two women's cancers," Zheng said. "More studies are needed to address the potential impact for this particular group of patients."
Consultation for patients is available at the High-Risk Clinic (694-CURE) at the Arizona Cancer Center, where a group of experts focus on the education, genetic counseling, screening and prevention of women at risk, particularly for breast, ovarian and endometrial cancer, Chambers added.