Primary lung cancer tumor may go undiagnosed in some kidney cancer patients

Could lung cancer be hiding in kidney cancer patients? Researchers with the Harold C. Simmons Comprehensive Cancer Center's Kidney Cancer Program studied patients with metastatic kidney cancer to the lungs and found that 3.5 percent of the group had a primary lung cancer tumor that had gone undiagnosed. This distinction can affect treatment choices and rates of survival.

"Kidney cancer spreads primarily to the lungs making the detection of a primary lung cancer difficult. Lung cancer is typically more aggressive than kidney cancer. Undetected, lung cancer may spread and eventually kill the patient," said Dr. James Brugarolas, Director of the Kidney Cancer Program and Associate Professor of Internal Medicine at UT Southwestern Medical Center.

Mel Moffitt, an Army veteran who survived serving in Vietnam, is among those now fighting both lung cancer and kidney cancer.

Mr. Moffitt, 70, was initially diagnosed with kidney cancer in 2008, leading to removal of one of his kidneys. By 2012, the cancer had spread to his lungs and lymph nodes. Before coming to UT Southwestern, he had been told he had less than a year to live. In 2015, a new primary tumor was found in his lung.

"It was like we turned around, and the cancer said 'By the way, I'm over here too,'" said his wife of 47 years, Kennon Moffitt, whom he met at the officer's club in El Paso before shipping off to Vietnam.

"I will keep fighting," pledged Mr. Moffitt, who has been through molecularly targeted drug therapy, stereotactic radiotherapy, and is combating his latest lung and kidney cancer diagnosis with immunotherapy and chemotherapy treatment.

Still, he said, he is grateful to have survived so many years since his initial diagnosis, years that included the birth of his three grandchildren, now ages 8, 6 and 4, and the chance to restore a 1969 red Corvette, which the couple plans to drive in a Fourth of July parade this summer.

Nearly 400,000 Americans are now living with a diagnosis of kidney cancer and more than 60,000 people are expected to be diagnosed with kidney cancer this year, according to the National Cancer Institute (NCI). Five-year survival rate averages range from more than 80 percent for stage 1, when cancer is contained in the kidney, to about 53 percent for stage 3, when it has spread beyond the kidney, to just 8 percent for stage 4, when the cancer spreads to more distant parts of the body or other organs.

Texas has the fifth-highest rate of this cancer in the U.S. and it is the fourth most common cancer treated at the Simmons Comprehensive Cancer Center, where survival rates for patients with stage 4 kidney cancer are double national benchmarks, noted Dr. Brugarolas, a Virginia Murchison Linthicum Scholar in Medical Research at UT Southwestern.

In this retrospective study of 151 patients at the Simmons Comprehensive Cancer Center, investigators identified 85 people who had kidney cancer metastasized to the lungs, and three who had a primary lung cancer. Investigators found only four previous cases described in the literature, leading them to suspect the incidence of lung cancers in kidney cancer patients may be underreported.

Because UT Southwestern is a tertiary care referral center, investigators noted that rates could be different in the general population. Up to 6 percent of patients with metastatic kidney cancer also may have a lung cancer, investigators noted in the study, published in Clinical Genitourinary Cancer.

"Our report raises an important flag for medical oncologists and radiologists to be on the lookout for a hidden lung cancer," said Dr. Brugarolas.