Which among the following is the latest classification for Wilms tumor based on surgical and pathologic findings?

The NWTS staging system is most widely used and is based on surgical and pathologic findings. The original classification was used in the first and second NWTS trials and was modified for NWTS III. Fuher modifications have been introduced to the staging in the NWTS V study. NWTS staging system for Wilms tumor: Stage I Tumor limited to kidney and completely excised Stage II Tumor extends beyond the kidney but is completely removed Stage III Residual non-hematogenous tumor confined to abdomen Stage IV Hematogenous metastases to lung, liver, bone, and brain Stage V Bilateral renal involvement at diagnosis Ref: Konety B.R., Williams R.D. (2008). Chapter 21. Renal Parenchymal Neoplasms. In E.A. Tanagho, J.W. McAninch (Eds), Smith's General Urology, 17e.