Wilms' Tumor - An Audit

Abstract

Background and aims: Outcome analysis of patients with Wilms' tumors (WT) is presented.

Materials and methods: A retrospective analysis of 23 children having WT managed by a single surgeon over 3 years (2021-2024) using the International Society of Paediatric Oncology Umbrella protocol was done.

Results: The median age at presentation was 36 months; 32 months and 24 months for the unilateral WT (uWT) (n = 19) and bilateral WT (bWT) (n = 4), respectively. M: F ratio was 2.3: 1. WTs were localized in 19 (uWT-16; bWT-3) and metastatic in 4 (uWT-3; bWT-1) patients. Core-needle biopsy was done in 22 patients (26 renal units). Pre-therapy contrast-enhanced computed tomography volumetry (n = 20) showed a median tumor volume of 1023 ml (range: 47-2680 ml). Post-neoadjuvant chemotherapy (NACT) median tumor burden (n = 19) was 612 ml (range 59-3775 ml). Post-NACT, tumor volume decreased in 11/18 patients but increased in seven patients. NACT was avoided in one neonate. Nephroureterectomy (including one with excision of bladder cuff) and nephron-sparing surgery were done in 17 and 10 renal units including 3 with multifocal WT, respectively. Risk stratification was intermediate in 21 and High in 2. Overall staging in 19 uWT included Stage I-7, Stage II-5, Stage III-4, and Stage IV-3 (local staging-stage I in 1 and stage II in 2). Local staging in 8 renal units with bWT was Stage I in 7 and II in 1. One stage IV uWT had bilateral pulmonary metastatectomy. Adjuvant chemotherapy has been completed in 18 patients; two patients are still on adjuvant chemotherapy; flank radiation was administered in six patients. Three patients with synchronous bWT died; two due to acute kidney injury in the immediate postoperative period and one with metastatic disease who had abandoned adjuvant chemotherapy after the 1^st cycle. Another patient died of a huge metachronous tumor in the contralateral kidney after a year of completion of therapy. One patient had successful multimodality treatment of local relapse with liver metastasis. 1-year overall and event-free survivals are 84% and 76%, respectively.

Conclusions: Excellent short-term results for localized uWT from a center in a low-middle-income country are reported.

Keywords: Adjuvant chemotherapy; Wilm’s tumor; event-free survival; histopathology; immunohistochemistry; neoadjuvant chemotherapy; non-Wilms’; overall survival; radiotherapy; relapse; renal tumors; risk stratification; staging.

Figure 1

Kaplan–Meier survival analysis curve for overall survival

Figure 2

Kaplan–Meier survival analysis curve for event-free survival

Figure 3

Kaplan–Meier survival analysis curve comparing overall survival between stages

Figure 4

Kaplan–Meier survival analysis curve comparing overall event-free survival between stages

Figure 5

Kaplan–Meier Survival analysis showing overall survival and event-free survival for Unilateral localised Wilms’ tumors

Figure 6

State-wise distribution of radiotherapy centres in India