The findings suggest that some women with stage IIIb cervical cancer, an advanced form of the disease, should receive aggressive therapies or treatment for pain control and comfort. Anurag K. Singh, M.D., radiation oncology resident at Barnes-Jewish Hospital, presented the findings Oct. 7 at the American Society for Therapeutic Radiology and Oncology's annual meeting in New Orleans. Singh is first author on the paper; the senior author is Perry W. Grigsby, M.D., professor of radiation oncology at the School of Medicine's Mallinckrodt Institute of Radiology.
"These findings are important because they mean we can design future studies to provide patients with different treatments based on the extent of their disease as shown on a whole-body PET scan," says Singh.
The retrospective study found that women with clinical stage IIIb cervical cancer fell into four distinct groups on the basis of PET scans. Women whose cancer had not spread to the lymph nodes had the highest rates of survival, followed by women with cancer cells in the pelvic lymph nodes only. Those whose tumors had spread to lymph nodes in the upper abdomen had poor survival, and those whose cancer had spread to lymph nodes in the upper chest usually died within months of diagnosis.
The American Cancer Society estimates that 13,000 new cases of cervical cancer will occur in 2002 in the United States and 4,100 will die from the disease. Because of mass screening programs, the prevalence of cervical cancer in the United States and other developed countries is generally low compared with developing countries, where the disease is a leading cause of cancer death among women.
For this reason, a worldwide staging system for cervical cancer, developed by the International Federation of Gynecology and Obstetrics (FIGO), is used both developing and developed countries. FIGO staging combines physical measurements - such as tumor size, location and the degree to which it has penetrated the cervical tissues - and medical tests that are broadly available worldwide.
A FIGO stage IIIb cervical cancer, for example, is a tumor that has penetrated the cervix and into the bladder or rectum. Historically, however, women with this type of tumor show a range of response to therapy.
"We did not really understand why these differences existed," says Grigsby. "These findings suggest the answer."
Grigsby also is a member of the Clinical and Translational Research Program at the Siteman Cancer Center at Washington University School of Medicine and Barnes-Jewish Hospital.
The study examined the records of 47 patients with FIGO stage IIIb cervical cancer who were evaluated before treatment by whole-body PET. Patients received a combination of brachytherapy (implanted radioactive devices), external-beam radiation therapy and chemotherapy.
According to the pretreatment PET scan, 13 (28 percent) had tumor cells that had spread to lymph nodes in the upper chest.
The three year survival estimates for the first three groups were 73 percent, 58 percent and 29 percent respectively, with none surviving at three years in the most advanced tumors.
The full-time and volunteer faculty of Washington University School of Medicine are the physicians and surgeons of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient-care institutions in the nation. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC HealthCare.