New Way to Detect Residual Bladder Cancer in Lymph Nodes

***EMBARGOED UNTIL WEDNESDAY, JUNE 13, 2001, 6:00 A.M. EST

CONTACT: Catherine Seigerman, U.Va.Health System Media Relations,804-924-5679

STUDY FINDS WAY TO DETECT RESIDUAL BLADDER CANCER IN LYMPH NODES

CHARLOTTESVILLE, Va., June 13, 2001 -- A highly sensitive method for detecting residual bladder cancer present in a patient's lymph node at the time of surgery has been discovered through a study conducted at the University of Virginia Health System and the University of Western Ontario. Dr. Dan Theodorescu, associate professor of urology and molecular physiology at U.Va., led the research which developed this molecular method which identified uroplakin, a gene specific to bladder tissue, in many lymph node samples that were found to be negative for bladder cancer when examined through the microscope. By identifying this residual disease, doctors can prescribe a method of treatment to prevent the clinical recurrence of this form of cancer.

"If we can identify which patients harbor residual cancer in the lymph nodes after surgery, there are new chemotherapies that could decrease the chance of the cancer coming back," Theodorescu said. "Our technique has picked up some of the cancers in the tissues that were thought to be negative when examined microscopically and that group of patients is the one who may benefit the most from such adjuvant chemotherapy. Basically, this is a more sensitive way to see if cancer has spread to the lymph nodes. The good news is any modern molecular diagnostic hospital lab has the capability to do this."

When a patient is diagnosed with bladder cancer, one form of treatment is a radical cystectomy, or surgical removal of the bladder and nearby lymph nodes. Once these organs are removed, the lymph nodes status is the primary prognostic factor. Traditionally, a pathologist would examine the tissue microscopically and determine if the lymph nodes were positive or negative for cancer. In this study, an enzymatic reaction--reverse transcription polymerase chain reaction (RT-PCR) for the Uroplakin II (UPII) gene--was utilized for the analysis of lymph node tissue samples. The RT-PCR found traces of uroplakin in some of the lymph nodes that were negative for cancer when examined through a microscope.

The study was conducted over a 10-month period at U.Va and at the University of Western Ontario in London, Ontario. Bladder cancer patients with muscle invasive disease underwent a radical cystectomy and at the completion of the procedure, biopsies of the lymph nodes and bladder were obtained for molecular analysis. The RT-PCR analysis was carried out on these specimens and results were compared with data obtained from conventional pathological examination. The study concluded that the molecular examination appears to identify patients that may harbor residual disease that is not identified by conventional histology although the ultimate clinical relevance of these studies needs to be validated in larger studies with longer follow-up.

Bladder cancer is the sixth most common cancer in the United States. It is estimated that there are more than 53,000 cases of bladder cancer in the U.S. and over 1,100 in the state of Virginia. It is more common among men than women and, when found and treated early, the chances for survival are very good.

The study will be published in the June 13, 2001 issue of Clinical Cancer Research.

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