The aim of this study is to evaluate histological changes in tumor-parenchymal interface in clear cell renal cell carcinoma (ccRCC) after neoadjuvant axitinib treatment.
We obtained clinical and pathology materials from 23 ccRCC patients treated with neoadjuvant axitinib in a phase II clinical trial, and from 23 matched patients with ccRCC that had upfront surgery. Histology of the tumor pseudocapsule and peritumoral kidney parenchymal change was evaluated and compared between the 2 cohorts.
A tumor pseudocapsule was noted in all the neoadjuvant axitinib patients (23/23) and control patients (23/23). Most pseudocapsules were non-continuous and only partially covered the tumor (axitinib 17/23 (74%) and control 19/23 (83%)). In the axitinib cases, median thickness of the intrarenal and external pseudocapsule was 1.4 mm and 2.4 mm and it was significantly thicker than control cases (intrarenal, P=0.0008 and external, P<0.0001). The thickness of the pseudocapsule in axitinib treated cases was irregular [axitinib 16/23 (70%) and control 9/23 (39%), P=0.0746]. Inflammation, nephrosclerosis, glomerulosclerosis and arteriosclerosis decreased with increasing distance from the tumor edge in both the neoadjuvant axitinib and control groups.
Tumor pseudocapsule becomes irregularly thick after neoadjuvant axitinib therapy. Although axitinib likely evokes a strong fibrous reaction in tumor-parenchymal interface, it does not affect the frequency of infiltrative tumor invasion to the outside of the pseudocapsule or the degree of atrophic/inflammatory change in the tumor surrounding tissue. These findings support the notion that PN could be safely done in well-selected patients after neoadjuvant axitinib.
The Journal of urology. 2016 Sep 24 [Epub ahead of print]
Fumi Kawakami, Priya Rao, Pheroze Tamboli, Christopher G Wood, Jose A Karam
Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center., Department of Pathology, The University of Texas MD Anderson Cancer Center., Department of Urology, The University of Texas MD Anderson Cancer Center., Department of Urology, The University of Texas MD Anderson Cancer Center. Electronic address: .