Gene technology identifies two types of papillary RCC

"Despite its moderate incidence, there is a disproportionately limited understanding of its underlying genetic programs," said Bin Tean Teh, MD, PhD, at the American Society of Clinical Oncology annual meeting here. "There is no effective therapy for metastatic papillary RCC, and patients are often excluded from kidney cancer trials."

Dr. Teh is deputy director for research operations and distinguished scientific investigator at the Van Andel Research Institute in Grand Rapids, MI. In 2000, he established a kidney cancer research program and now has about 15 scientists working on kidney cancer. One of the group's current areas of research is the use of genomic microarray analysis to identify two distinct types of papillary RCC with contrasting prognoses.

Papillary RCC encompasses about 20% of the surgical series of kidney cancer and about 10% of metastatic series. His group has idenfitied two distinct types of molecular subclasses of papillary RCC that are biologically and clinically distinct, and that are characterized by distinct gene expression profiles, distinct chromosomal alterations, and distinct putative molecular pathways.

"This may also have therapeutic implications. We looked at each molecular pathway and tried to identify the targets that are involved in these tumors and hopefully, we can design the proper treatment for these types of tumors," Dr. Teh said.

By using genetic technology to recognize gene expression profiles, physicians will potentially be able to identify the cases of papillary RCC associated with a potentially poor outcome and can use the biomarkers to identify these patients.

"Genes that are thus identified may serve as potential molecular therapeutic targets, which is very important," Dr. Teh said.

Commenting on Dr. Teh's presentation, Janice Dutcher, MD, professor of medicine at New York Medical College, Bronx, NY, noted that papillary RCC represents a very small sub-type of metastatic renal cell cancer.

Dr. Dutcher called Dr. Teh's presentation exciting and professed to be "very impressed that there is such a clear delineation that you could see such difference in such small numbers of patients."