The Prognostic Role of Sarcopenia in Wilms Tumor: Does It Influence Surgical Outcomes and Survival?

Background: Sarcopenia (SP) is described as a prognostic factor in adult and pediatric cancer patients. However, there are no data regarding Wilms tumor (WT). We aimed to study the association between sarcopenia and oncological outcomes in WT.

Methods: A retrospective study of patients diagnosed with WT at our institution between 2010 and 2022 was performed. SP at diagnosis was assessed by measuring the psoas muscle area (PMA) at the L4-L5 level on computed tomography (CT)/magnetic resonance imaging (MRI), and was defined as z-score values ≤2. Demographics, complications, and outcomes were analyzed.

Results: Forty-eight patients (50% male) were included, with a mean age of 44.91 ± 31.12 months. Twelve patients (25%) had SP at diagnosis versus 36 (75%) who did not. Forty-one patients (85%) underwent total nephrectomy and seven (15%) nephron-sparing surgery (NSS). No statistical differences were found in demographics, risk group, or treatment between the SP and non-sarcopenic (NSP) groups. SP was associated with a higher rate of postsurgical complications (33% for the SP-group vs. 5.6% for the NSP-group; p = 0.023) and with a higher rate of relapse (33% vs. 14%, respectively; p = 0.09). With a median follow-up of 57.75 (1.87-150.8) months, event-free survival (EFS) was lower for the SP group (84.20 ± 17.45 vs. 135.40 ± 8.65 months, respectively; p = 0,08). One patient in the SP group died. The 5-year overall survival (OS) was 89% for the SP group versus 100% for the NSP group.

Conclusions: Among our patients, SP can be considered a risk factor for complications in patients with WT and could be associated with poor outcomes, increasing the risk of relapse and decreasing EFS.