A new research study completed by the Gynecologic Oncology Group and headed by Dr. Cornelia Trimble of the Johns Hopkins Kimmel Cancer Center found that uterine biopsy – normally thought to be the most definitive indicator of the presence of cancerous or precancerous cells in the uterus – is far less conclusive than previously thought, the Johns Hopkins Medicine web site and other sources reported June 2.
The study, which will be presented at the 40th annual American Society of Clinical Oncology, found that pathologists who routinely evaluate uterine biopsies to check for cancer and other abnormalities disagree frequently – as much as 60 percent of the time, in fact – about what the cells they are examining indicate.
"This study," noted Trimble, "brought into sharp focus the fact that it is very difficult to make an accurate diagnosis from uterine biopsies." Yet, since the most effective treatment option for uterine cancer is complete hysterectomy – the complete removal of the uterus and cervix – with additional chemical or radiation therapy, the stakes are high. If the uterus is not removed after a false negative result, then women face the possibility of the cancer’s spread and increased risk of fatality; on the other hand, younger patients who opt for hysterectomy are closing the doors on any possibility of bearing children in the future.
A faulty test result could lead to a potentially severe outcome, says Trimble, "So we suggest these patients get a second opinion from a pathologist who specializes in gynecology."
Uterine cancer is the most common reproductive cancer in the United States. It is characterized by the presence of cancerous uterine or endometrial (uterine lining) cells or precancerous lesions called atypical endometrial hyperplasia (AEH).
During the study, Dr. Trimble and colleagues evaluated the biopsies of 289 patients originally thought to have AEH, and their examination yielded results that agreed with the original findings in only 39.8 percent of cases. 25.6 percent of the cases were downgraded to non-cancerous status, while 29.1 percent of the cases were upgraded to full-blown cancer. 5.5 percent were unable to be diagnosed.
While current guidelines for the diagnosis of cancer by of uterine biopsy have been approved by both the World Health Organization and the Society of Gynecologic Pathologists, Dr. Trimble notes that these guidelines are not as strict as those for other forms of cancer, including cervical cancer.
In response to the study’s findings, Dr. Trimble says, "We will be looking at these data more closely to determine why there was such disagreement in the diagnosis and find a better system for classifying and grading these biopsies, including using improvements in molecular markers to help identify better ways to diagnose uterine cancer."