Researchers at The University of Texas MD Anderson Cancer Center recently published their latest findings on the role a diagnosing urologist plays in deciding whether older men with low-risk prostate cancer should receive treatment for their disease, and consequently the type of treatment they receive.
Prostate cancer is the most common non-skin cancer in men, with 233,000 new cases being diagnosed every year, according to the American Cancer Society, with similar mortality rates between older patients that opt for surveillance versus treatment.
“What’s striking was just how much variation exists in managing prostate cancer, with the diagnosing physician playing as much a role, if not more of a role, than accepted patient factors that impact surveillance use,” said Karen Hoffman, M.D., assistant professor in Radiation Oncology and lead author of the study.
The findings, published in JAMA Internal Medicine, aimed to determine why active surveillance, a management program for low-risk disease including repeated prostate exams and biopsies (PSAs), is not commonly used in this patient population.
Using the Surveillance, Epidemiology and End Results (SEER) registry, researchers identified 12,068 men ages 66 and older diagnosed with low-risk prostate cancer from 2006—2009 alongside physician characteristics such as medical degree, year of training, training location and board certifications obtained from linked Medicare. Additionally, the investigators also sought to determine the impact of the diagnosing urologist on treatment decisions, quantify the rate of surveillance versus treatment and identify urologist and patient factors associated with surveillance selection.
Of the 12,068 men studied, 80% received treatment and only 20% underwent observation, with observation rates varying considerably between a total of 2,145 urologists, from 4.5 to 64.2%, and radiation oncologists, from 2 to 47%. As such, the team found that the diagnosing urologist accounted for more than double the rate of variation seen in treatment versus observation decisions compared to individual patient characteristics such as age, comorbidities and PSA level.
They concluded that no cancer-directed therapy was preformed within 12 months of diagnosis and that physicians influence decision-making as well as the type of treatment selected, verifying that patients diagnosed by urologists who treated low-risk prostate cancer are more likely to receive treatment as well as a therapy commonly used by their urologist. Treated patients were more likely to undergo prostatectomy, cryotherapy, brachytherapy, or external-beam radiotherapy if their urologist billed for that treatment. These observations raised some financial considerations, although the research could not determine those physicians with ownership interests in radiation equipment.
“Primary care physicians play a key role because they refer patients to urologists for elevated PSA levels and prostate biopsies. Increasing transparency could lead to selecting physicians more open to surveillance,” Hoffman said, stressing that public reporting of physician’s cancer management profiles would enable primary care providers and patients to make more informed decisions regarding prostate cancer diagnose and treatment.
Future studies intend to address if patient counseling in a multidisciplinary setting and patient decision aids increase active surveillance acceptance.
This study was supported by grants from the Cancer Prevention and Research Institute of Texas, the National Cancer Institute, the American Cancer Society, the McCombs Institute, Center for Radiation Oncology Research at MD Anderson and the National Cancer Institute.
In addition to Hoffman, other authors on the all MD Anderson study include: Benjamin Smith, M.D., Grace Smith, M.D., Ph.D., Thomas Buchholz, M.D., George Perkins, M.D., Deborah Kuban, M.D. of Radiation Oncology; Sharon Giordano, M.D. and Jiangong Niu, Ph.D. of Health Services Research; Yu Shen, Ph.D. and Jing Jiang of Biostatistics; John Davis, M.D. and Jay Shah, M.D. of Urology; Jeri Kim, M.D. of Genitourinary Medical Oncology; and Robert Volk, Ph.D., General Internal Medicine.