Blazing a trail tackling deadly complication of kidney cancer

The Kidney Cancer Program at UT Southwestern Medical Center’s Harold C. Simmons Comprehensive Cancer Center has a long-standing tradition of executing complex kidney cancer surgeries, such as those involving tumors invading the largest vein of the body, the inferior vena cava or IVC. Now investigators report a new prognostic factor, better radiologic tests, and a new treatment paradigm.

Rates of recurrence after surgery from tumors invading the IVC vary from 20 to 60 percent. To help identify factors that can affect recurrence, Dr. Vitaly Margulis, Associate Professor of Urology, and Dr. Michael Wait, Professor of Cardiovascular and Thoracic Surgery, led a research team of top-tier surgeons from Mayo Clinic, MD Anderson Cancer Center, Emory University, Indiana University, and the University of Wisconsin.

They determined that when tumors invading the IVC triggered the development of a blood clot, the chances from dying from kidney cancer were increased fourfold.

Published in Urology, the study followed 446 patients with kidney tumors that invaded the IVC, who were treated with surgery. The patients were split into two groups – those who developed a blood clot (174) and those who did not (272). The investigators found that the presence of a blood clot was associated with a more advanced stage of the disease, more complications during surgery, and an increased risk of dying from kidney cancer.

Notably, blood clots can be identified using magnetic resonance imaging (MRI), “Which has now become a new standard for evaluating these patients,” said Dr. Ivan Pedrosa, Jack Reynolds, M.D., Chair in Radiology, and Chief of Magnetic Resonance Imaging (MRI).

“These important findings provide a new radiological marker for counseling patients and building the most effective, interdisciplinary treatment plans,” said Dr. Margulis, corresponding author of the study. “The results will help patients in making decisions about surgery, as well as participation in advanced clinical trials available at UT Southwestern.”

Data shows that up to 10 percent of patients with kidney cancer have IVC involvement, and even after surgery, 50 percent of patients develop recurrent metastatic disease.

Although surgery is the only treatment with proven efficacy, UT Southwestern researchers are investigating new possibilities. Previously, Dr. Raquibul Hannan, Associate Professor of Radiation Oncology and Immunology, and colleagues reported that stereotactic ablative radiation therapy (SAbR) has the potential to control kidney cancer invading the IVC. This approach, which was reported for the first time by UT Southwestern investigators in 2015 (Hannan et al., Cancer Biol Ther 2015), is now being evaluated in a prospective clinical trial.

In the clinical trial, patients are offered SAbR prior to surgery. “Treatment of the tumor inside the vein with SAbR may reduce the chances of spread during surgery,” says Dr. Hannan. While the clinical trial has been open for just a few months and only a handful of patients have enrolled so far (see KCP Clinical Trials), the concept drew so much attention that it was selected as a Late Breaking Abstract for presentation at the Plenary Session of the American Urological Association Annual Meeting in May, 2018.

Six newly diagnosed patients with IVC involvement received neo-adjuvant SAbR followed by surgery with removal of the kidney and the thrombus within 4-14 days after the patients’ last SAbR treatment. The approach was safe and there were no serious complications. Patients are currently being followed up to assess the impact of SAbR on recurrence rates.

“These studies showcase the multidisciplinary approach to kidney cancer that characterizes UT Southwestern. They involve teams of experts across the specialties of urology, cardiothoracic surgery, radiology, and radiation oncology,” says Dr. Jim Brugarolas, Sherry Wigley Crow Endowed Chair in Cancer Research, and Director of the Kidney Cancer Program.