Does bilateral Wilms' tumor involving the collecting system in children have a worse prognosis?

Abstract

Abstract Objective To summarize the clinical characteristics, treatment methods and prognosis of bilateral Wilms' tumor (BWT) in children involving the collecting system. Methods Patients with BWT admitted to our pediatric surgery center between January 2008 and June 2022 were reviewed. Children were grouped according to the relationship between the tumor and the collecting system. Group Ⅰ included children with tumor infiltrating the collecting system, group Ⅱ included children with tumor growing into the collecting system, and group Ⅲ included children whose tumor did not involve the collecting system. The clinical features, treatments and prognosis of the patients were analyzed. Results Seventy patients were enrolled, including 20 patients with 25 sides of tumors infiltrating the collecting system in group Ⅰ,10 patients with 13 sides of tumors growing into the collecting system in group Ⅱ, and 40 patients in group III. There was no significant difference in patients age and gender between group I and group II. In total, 20 patients in group Ⅰ and 9 patients in group II had partial response (PR) after neoadjuvant chemotherapy. In group I, 22 of 25 sides of tumors underwent nephron-sparing surgery (NSS); in group Ⅱ, 11 of 13 sides of tumors underwent NSS. During an average follow-up of 47 months, in group I, 6/20 patients relapsed and 2/20 patients died; in group Ⅱ, 3/10 patients relapsed and 1/10 patient died. There was no significant difference in 4-year overall survival (OS) rate among groups I, Ⅱ and Ⅲ(86.36% vs. 85.71%vs. 91.40%, P = 0.902). Conclusions To preserve renal parenchyma, NSS is feasible for children with BWT involving the collecting system. There was no significant difference in postoperative long-term OS between patients with BWT involving the collecting system and not involving the collecting system.