Renal mass biopsy to guide treatment decisions for small incidental renal tumors: a cost-effectiveness analysis.
OBJECTIVE
To evaluate the effectiveness, cost, and cost-effectiveness of using renal mass biopsy to guide treatment decisions for small incidentally detected renal tumors.


METHODS
A decision-analytic Markov model was developed to estimate life expectancy and lifetime costs for patients with small (< or = 4-cm) renal tumors. Two strategies were compared: renal mass biopsy to triage patients to surgery or imaging surveillance and empiric nephron-sparing surgery. The model incorporated biopsy performance, the probability of track seeding with malignant cells, the prevalence and growth of benign and malignant tumors, treatment effectiveness and costs, and patient outcomes. An incremental cost-effectiveness analysis was performed to identify strategy preference under a willingness-to-pay threshold of $75,000 per quality-adjusted life-year (QALY). Effects of changes in key parameters on strategy preference were evaluated in sensitivity analysis.


RESULTS
Under base-case assumptions, the biopsy strategy yielded a minimally greater quality-adjusted life expectancy (4 days) than did empiric surgery at a lower lifetime cost ($3466), dominating surgery from a cost-effectiveness perspective. Over the majority of parameter ranges tested in one-way sensitivity analysis, the biopsy strategy dominated surgery or was cost-effective relative to surgery based on a $75,000-per-QALY willingness-to-pay threshold. In two-way sensitivity analysis, surgery yielded greater life expectancy when the prevalence of malignancy and propensity for biopsy-negative cancers to metastasize were both higher than expected or when the sensitivity and specificity of biopsy were both lower than expected.


CONCLUSIONS
The use of biopsy to guide treatment decisions for small incidentally detected renal tumors is cost-effective and can prevent unnecessary surgery in many cases.
Pandharipande
Pari V
PV
Department of Abdominal Imaging and Interventional Radiology, Institute for Technology Assessment, Massachusetts General Hospital, Boston, MA 02114, USA. pari@mgh-ita.org
Gervais
Debra A
DA
Hartman
Rebecca I
RI
Harisinghani
Mukesh G
MG
Feldman
Adam S
AS
Mueller
Peter R
PR
Gazelle
G Scott
GS
D000704:Analysis of Variance; D001706:Biopsy / Q000191:economics*; D002292:Carcinoma, Renal Cell / Q000473:pathology*; D003362:Cost-Benefit Analysis; D003365:Costs and Cost Analysis; D003657:Decision Making; D006801:Humans; D033162:Incidental Findings; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery; D008017:Life Expectancy; D008390:Markov Chains; D019057:Quality-Adjusted Life Years; D012680:Sensitivity and Specificity