Quality and Outcome Metrics for Curative-Intent Interventional Oncology Procedures

Quality and outcome metrics for interventional oncology (IO) procedures do not exist.  By examining metrics such as length of stay, 30-day mortality, and 30-day readmission rates after surgery,  the National Surgical Quality Improvement Program (NSQIP) established pivotal surgical quality thresholds.  The purpose of this study was to establish baseline outcome measures for IO interventions performed for curative intent in cancer patients and to evaluate the predictive value of risk factors associated with poor surgical outcomes to IR interventions.

Materials and Methods:

A single institution retrospective review of liver and renal ablations performed for curative intent between 4/1/2020 – 10/1/2022 was conducted at a cancer center. In addition to demographic characteristics, the presence of five comorbidities (performance status, diabetes, COPD, hypertension requiring medication, and myocardial infarction) found to recapitulate patient frailty for patients undergoing surgery (Subramaniam et al.) was evaluated for each patient. Outcome measures including length of stay, 30-day readmissions, and mortality were determined. Univariable and multivariable analysis for the significance of the 5 frailty indices on prolonged length of stay was performed. All statistical analysis was conducted using R (R Foundation).

Results: A total of 643 patients were identified during the study period, with a median age of 64 (53 – 72 IQR). Microwave liver ablation (69%) comprised the majority of interventions, followed by radiofrequency renal ablation (21%) and renal cryoablation (10%). The most common ECOG status was 0 (55%), followed by 1 (37%), and 2 (7%). The most common histology was adenocarcinoma (34%). Diabetes, COPD, MI, and hypertension requiring medications were present in 31%, 4.2%, 4.9%, and 35% of the study cohort, respectively. The 30-day, 1 year, and 2 year survival rates were 100%, 94%, and 89%, respectively. The 30-day readmission rate was 0.6%.  A total of 30 patients (5.0%) had hospital lengths of stay longer than 1 night. On univariate and multivariate analysis, the type of intervention (liver ablation) and cancer type were significantly associated with this outcome, while the five frailty variables were not.

Conclusion: Mortality, 30-day readmissions, and length of stay greater than 1 night following curative-intent liver and renal ablations are low. Frailty, which has been associated with poor surgical outcomes, may not be relevant to oncology patients undergoing liver and renal ablations.