ASCO GU 2018: Self-reported Quality of Life as a Predictor of Survival in Renal Cell Carcinoma

San Francisco, CA (UroToday.com) While biomarkers for various malignancies continue to be developed, sometimes there can be no substitute for a physical and mental exam. Clinical evaluation of the patient may provide guidance into their cancer-related status and perhaps even serve as a biomarker.

In this abstract, the authors utilize patient-reported outcomes to assess if quality of life can be a biomarker for survival in patients with renal cell carcinoma.To do so, they use the Medicare Health Outcomes Survey linked to SEER data from 1998-2014 (17 years).

Medicare Health Outcomes Survey was assessed for two main components: mental component summary (MCS) and physical component summary (PCS). MCS and PCS scores were classified as high (≥50) or low ( < 50) based on a population mean score of 50 points. High (designated as “+”) implies better QOL than low (designated as “-“).Patients were classified into four groups: 1) high MCS, high PCS; 2) high MCS, low PCS; 3) low MCS, high PCS; and 4) low MCS, low PCS.
• It is never stated when the surveys were completed in relation to treatment.

The primary outcome was association with all-cause mortality (ACM). However, they also completed a competing risks models adjusted for stage, demographics, and comorbidities to evaluate RCC-specific and non-RCC-specific mortality.

They identified 1,494 patients with a median age of 73.4 years (IQR 68.8-79.3); median follow-up was 5.6 years (IQR 4.0-8.3). There were 747 deaths (all-cause) and 139 RCC-related deaths.
71% of the entire cohort was cT1 and only 15% were cT3-4. 3.4% were metastatic RCC.

While the four subgroups were somewhat balanced, there were clear discrepencies:
- Group 3 had a higher proportion of cT1 than the other 3, and less cT3-4
- Each successive group (1->4) had higher rates of metastatic disease
- Each successive group (1->4) had higher rates of cardiovascular risk factors
- Each successive group (1->4) had lower rates of male patients

On multivariable analysis, each additional MCS and PCS point reduced the hazard of ACM by 1.3% (95% CI 0.981-0.993, P< 0.001) and 2.2% (95% CI 0.972-0.985, P< 0.001), respectively. Therefore, patients that had better mental and physical QOL had reduced ACS.

In the competing risks model, the hazard ratio (HR) of RCC mortality in Groups 2, 3, and 4 were 2.71 (95% CI 1.18-6.22, P= 0.02), 4.55 (95% CI 1.57-13.18, P= 0.005), and 3.11 (95% CI 1.35-7.16, P= 0.008), respectively, compared to Group 1. The HR for non-RCC mortality were 1.50 (95% CI 1.16-1.94, P= 0.002), 1.03 (95% CI 0.59-1.78, P= 0.9), and 1.83 (95% CI 1.41-2.38, P< 0.001), respectively, relative to Group 1.

It would appear, based on this analysis, that patients with worse physical and mental self-reported QOL metrics is associated with worse ACM in RCC patients with good accuracy; lower PCS and MCS scores led to higher rates of ACM, even after accounting for differences in disease, demographics, and comorbidity. This carried forward to RCC specific mortality. In non-RCC mortality, however, low physical health was more associated with worse outcomes than poor mental health.

However, this is obviously limited by the fact that this patient-reported. More importantly, the groups were soor poorly balanced, the difference likely represent differences in metastatic disease rates, cardiovascular disease, and clinical stage.

Speaker: Ridwan Alam

Co-Authors: Hiten Patel, Phillip M. Pierorazio

Institution(s): James Buchanan Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, MD; Johns Hopkins University, Baltimore, MD

Written by: Thenappan Chandrasekar, MD, Clinical Fellow, University of Toronto, Twitter: @tchandra_uromd at the 2018 American Society of Clinical Oncology Genitourinary (ASCO GU) Cancers Symposium, February 8-10, 2018 - San Francisco, CA