Laparoscopic nephrectomy for Wilms' tumor: Can we expand on the current SIOP criteria?

INTRODUCTION: Wilms' tumor now has a good overall prognosis with open radical nephrectomy having been the mainstay of surgical treatment. Recently laparoscopic nephrectomy (LN) has been growing in popularity. The aim of our study was to review our indications and outcomes for laparoscopic resections for Wilms' tumor and compare indications with International Society of Paediatric Oncology (SIOP) criteria for LN. MATERIAL AND METHODS: Patient demographics, preoperative management, surgical data, respect of SIOP criteria, complications, disease outcome, and follow-up were recorded on consecutive children who underwent nephrectomy for Wilms' tumor. RESULTS AND DISCUSSION: Fifty-four consecutive children with Wilms' tumor underwent a nephrectomy; 20 had a LN (Table). Nine of 20 (45%) patients who had LN did not meet SIOP criteria for LN. No patients had an intraoperative tumor rupture and one patient had positive margins because of preoperative rupture. There were two conversions: one caused by difficulty accessing the renal hilum and the other caused by difficulty maintaining oxygen saturations. There was one local recurrence. CONCLUSION: SIOP criteria are conservative and safe. Indications can be extended for teams experienced in surgical oncology and laparoscopy after agreement at a multidisciplinary meeting (MDM).

What is the risk of local recurrence after laparoscopic transperitoneal radical nephrectomy in children with Wilms tumours? Analysis of a local series and review of the literature.

BACKGROUND: To reduce long-term morbidity (adhesions-related complications and impaired quality of life due to scars), laparoscopy has been used as an alternative to open surgery in Wilms tumours (WTs). However, concerns have been raised on the risk of local recurrence after this type of resection. OBJECTIVE: The aim was to determine the incidence of local recurrence after laparoscopic transperitoneal radical nephrectomy (LTRN). STUDY DESIGN: We analysed 18 local cases and conducted a review of the English literature in Pubmed from 2004 to 2017 with the following keywords: (Wilms OR nephroblastoma) AND (laparoscopy OR minimally invasive surgery) AND 2004:3000. The review was conducted according to PRISMA guidelines. Data were collected independently in duplicate in a preformed Excel database. Review articles and duplicated case reports were excluded. Patients with retroperitoneoscopic or nephron-sparing surgery were also excluded. RESULTS: One hundred and four LTRNs have been performed for WT with neoadjuvant chemotherapy in 93 cases. Tumour was ruptured preoperatively in three cases but never intraoperatively. The median volume of the tumour was 229.4 mL (3.8-776 mL). Local stage was specified in 86 cases: 49 stage I, 28 stage II, and nine stage III. Lymph nodes were sampled in 48 patients (median 2.3 [0-14] nodes). Histology was reported in 90 cases: 27 favourable and two unfavourable histology (COG); and six low, 50 intermediate, and five high-risk tumours (International Society of Paediatric Oncology). With a median follow-up of 20.5 months (1-114 months), there were four local recurrences (3.8%) at a median of 8.5 (7-9) months after surgery. Three tumours were initial local stage I (2 intermediate and 1 high risk) and one stage III. The results are presented in the Figure. DISCUSSION: The incidence of local recurrence after LTRN is 3.8%. This is lower than previously reported after open resection. However, tumours amenable to minimally invasive surgery are smaller, with higher numbers of low stage and standard histology. Additionally, the quality of the reports is suboptimal and follow-up is relatively short. CONCLUSION: LTRN does not seem to increase the incidence of local recurrence in WT but inclusion of patients in international protocols with prolonged and systematic follow-up is of utmost importance to carefully evaluate this risk.