Surgical Management of Bilateral Wilms Tumors

According to the 2016 Wilms tumor guidelines of the International Society of Pediatric Oncology (SIOP) (13 (link)), children with bilateral Wilms tumors first received neoadjuvant chemotherapy. Preoperative chemotherapy drugs included Actinomycin D combined with Vincristine and Epirubicin. Surgical assessment using imaging techniques was first performed after 2 cycles of chemotherapy, and thereafter after every 2 cycles. In non-resectable cases, the number of preoperative chemotherapy courses was increased.
If deemed resectable, one of the 3 following operation methods was chosen: 1. Radical nephrectomy was performed for huge tumors when the kidney could not be preserved at all. 2. NSS surgery was performed for small tumors that could be removed in vivo completely. 3. Renal tumor ex vivo resection and autologous kidney in-situ transplantation was selected for huge or multiple tumors adjacent to the renal hilum; or located in the deep middle of kidney, or proximal to renal vessels.
Intraoperatively, the patient was placed in a supine position, the lumbar region was elevated, and a transverse incision was made on the upper abdomen. Intraoperatively, the renal hilar vessels and ureters were freed, and sufficient lengths of the ureters and renal hilar vessels were reserved. The proximal renal artery and vein were clamped with blood vessel clamps. The distal ureter was also handled, and the kidney (including the tumor) was removed. While removing the renal tumor in vitro and processing the renal pelvis and blood vessels, another group of surgeons removed the retroperitoneal lymph nodes.
The isolated kidney was immediately placed in sterile ice pellets to lower the kidney's temperature. Within 2 min, 4 °C hypertonic citrate adenine solution (HCA) cryopreservation solution was simultaneously injected. The preservation solution was perfused in the kidney to completely replace the residual blood. This perfusion was continued during the whole process of removing tumors and kidney repairing in vitro to keep the kidney in a bloodless state. After incising the renal capsule, tumors were peeled from the normal tissue carefully with complete tumor capsule. Hemostasis and ligation were given to blood vessels at the cutting edge, and renal arteries and veins were trimmed for anastomosis. Then, we repaired the damaged renal system, and sutured the renal capsule. The excised and processed tumor-free kidney was orthotopically implanted into the body (Figure 1). The renal artery and vein were sutured end-to-end. The ureter was also anastomosed end-to-end, with a built-in double J tube. Depending on the surgeon's experience, a ureteral stent can be placed during the operation for drainage, to reduce anastomotic pressure. A perinephric drainage tube can also be placed at the same time to drain the leaked urine.