Biomarker for nutritional status helps assess postcystectomy prognosis for patients with bladder cancer
Patients with bladder cancer are two times more likely to have complications after a radical cystectomy procedure if they have a biomarker for poor nutritional status before the operation, according to a study presented at the 2013 Clinical Congress of the American College of Surgeons in Washington, DC. A low preoperative level of albumin was identified as a potentially modifiable risk factor for postsurgical problems. Albumin is a marker of the protein level in blood.
The study was led by David C. Johnson, MD, MPH, of the University of North Carolina School of Medicine in Chapel Hill. The research team evaluated the impact of patients' nutritional status before radical cystectomy on the rate of complications within 30 days after the operation. Radical cystectomy is a procedure that involves the surgical removal of the bladder and lymph nodes.
The researchers mined the American College of Surgeons National Surgical Quality Improvement Program database to analyze postoperative complications data from 1,085 patients who underwent radical cystectomy at 315 medical centers across the United States from 2005 to 2011. This database is a nationally validated, risk-adjusted, outcomes-based program to measure and improve the quality of care in private sector hospitals.
Bladder cancer will be newly diagnosed in more than 72,500 people this year, the American Cancer Society estimates, and about one-third of all cases involve cancer that has spread into the muscular wall of the bladder, which permits spread to other organs. For these patients, radical cystectomy is the standard treatment, but the complication rate after the operation remains high, particularly for infections and poor wound healing, explained study authors.
"Poor nutrition is a known risk factor for adverse results after radical cystectomy," Johnson explained. "The prevalence of nutritional deficiency is very high in patients with bladder cancer, partly because of their disease and partly because of their advanced age—73 years on average."
Among study patients who experienced complications within the first month after the surgical procedure, the authors looked for the presence of a low albumin level (less than 3 g/dL); weight loss greater than 10% of body weight 6 months before the operation; and obesity, defined as a body mass index (BMI) of 30 kg/m2 or higher.
Study results showed that 575 patients (53%) experienced complications within the first month after the surgical procedure. The investigators found that only low albumin level was a significant predictor of experiencing a postoperative complication. Patients with low albumin levels before surgery had 2.1 times the risk of having a complication within 30 days after the operation compared with those whose albumin level was in a normal range or above (3 g/dL and higher), the authors reported.
"There's very little risk in improving nutritional status before the operation and significant possible benefits," said a study coauthor Angela Smith, MD, an assistant professor of urology at UNC.