Presentation Authors: Andrew Silagy*, New York, NY, Julian Marcon, Roy Mano, Cihan Duzgol, Kyle Blum, Renzo DiNatale, Oguz Akin, Jonathan Coleman, Paul Russo, Ari Hakimi, New York City, NY
Introduction: Cytoreductive nephrectomy (CN) for clear cell renal cell carcinoma (RCC) may be undertaken on patients with varying tumor size and metastatic burden. A recent publication reported that the percentage of overall disease resected may predict post-operative survival. We aimed to validate this finding and further explore the importance of number and distribution of metastases.
Methods: After obtaining IRB approval, we reviewed 68 patients who underwent CN with clear cell histology and had a pre-operative contrast enhanced Computer Tomography (CT) available for review.CT scans were reviewed with image segmentation analysis software (TerareconÂ®). Measurement of all discernable disease, irrespective of size, was performed. The tumor and metastases&[prime] RECIST values, volume, compactness, mean attenuation, location and number were measured. Baseline clinicopathological characteristics were recorded. Tumor volume resected was categorized based on previous publications and their association with outcome was evaluated with Cox regression analyses. Associations between outcome and the residual disease volume, number and site of lesions were also evaluated.
Results: The study cohort included 68 patients with a median age of 58 years (IQR 53 - 66); 25% of patients were female. 22% of patients had a pre-operative metastasectomy. 96% of patients had a KPS â‰¥80. Median follow-up for survivors was 26 months (IQR 22 - 30). 2- and 5-year survival rates were 60% and 16%, respectively.The median total disease volume was 236cm3 (IQR 95 - 522) most of which was confined to the primary tumor (median 98.6%; IQR 89.3 - 99.6) (Figure 1A).Published cutoffs of fraction of disease resected ( < 90%, 90-95% and >95%) did not predict for overall survival in this cohort (Figure 1B). On multivariate analysis disease volume >236cm3 (HR 2.16 (CI 1.18 - 3.97) p = 0.01) and number of lesions (HR 2.10 (CI 1.07 - 4.11) p =0.03) were statistically significant predictors of overall survival.
Conclusions: Our findings demonstrate that oligometastatic disease and lower total volume of disease predicted for a better outcome following CN. However, the findings were not significant when using the previously reported cutoffs. Patients with lower volume of disease should be considered more favorably for surgical management.
Source of Funding: This research was funded in part through the NIH/NCI Cancer Center Support Grant P30 CA008748