TIMP-1 as well as Microvessel Invasion and High Nuclear Grade Is a Significant Determinant Factor for Extension of Tumor Diameter in Localized RCC

Objectives. To clarify what kind of pathological factor is necessary for the extension of tumor diameter in localized RCC, we studied localized RCC patients. Methods. We retrospectively reviewed medical records of 237 RCC patients in our institute who underwent nephrectomy. We performed immune histological analysis of MMP-2, MMP-9, TIMP-1, TIMP-2, and MT-MMP-1 for all samples. Results. Among the clinicopathological factors, multivariate analysis revealed nuclear grade; TIMP-2 and MT-MMP-1 were independent prognostic factors of localized RCC (risk ratio 1.50, p = 0.037, risk ratio 1.12, p = 0.008, and risk ratio 1.84, p = 0.045, resp.). By the multiple logistic regression analysis among pT1a versus pT1b, TIMP-1 was an independent factor (risk ratio 3.30, p = 0.010) whereas all pT1 versus pT2a and all pT1 + pT2a versus pT2b high nuclear grade (risk ratio 5.15, p = 0.0015) and Micro vessel invasion (MVI, risk ratio 3.08, p = 0.002) were independent factors. For all pT1 + pT2a versus pT2b, nuclear grade (risk ratio 3.39, p = 0.020) and MVI (risk ratio 2.91, p = 0.018) were independent factors. Conclusion. Higher expression of TIMP-1 is necessary for advancement tumor diameter from pT1a to pT1b, and a process of tumor diameter extension beyond pT1 and pT2a category needs presence of MVI and high nuclear grade.