상부요로상피암에서 신장보존수술: 요관암에 대한 수술적 치료의 패러다임 변화

Abstract

Introduction Ureter cancer presents a unique benefit with a range of kidney-sparing surgical options, contrasting with renal pelvis cancer. Current guidelines lack a nuanced consideration of renal function, focusing predominantly on risk-based disease management and without distinction between renal pelvis and ureter cancers. In this study, I aimed to demonstrate appropriate management for ureter cancer, especially in terms of kidney sparing surgery (KSS), by comparing the oncologic outcomes and renal function between patients who underwent radical nephroureterectomy (RNU) and those who underwent KSS.

Materials and Methods Between 2011 and 2019, 708 upper tract urothelial carcinoma (UTUC) patients underwent RNU (N = 646) or KSS (N = 62) at Asan Medical Center. Retrospective analysis highlighted tumor unifocality as a significant prognostic factor in non-invasive (≤pT1) UTUC. Subgroup analysis focused on unifocal ureter cancer (UUC) to analyze renal function and oncological outcomes between RNU and KSS. Ultimately, I aimed to identify potential KSS candidates among patients with ureter cancer who initially underwent RNU.

Results No significant differences were observed in intravesical recurrence-free survival (IRFS), metastasis-free survival (MFS), cancer-specific survival (CSS), or overall survival (OS) between RNU and KSS groups in UTUC. In non-invasive (≤pT1) UTUC subgroup, tumor multifocality emerged as an independent risk factor for CSS (HR = 2.221, 95% CI: 1.231-4.010, P = 0.008). In non- invasive (≤pT1) pure ureter cancer (PUC) subgroup, tumor multifocality was also identified as a significant risk factor for CSS (HR = 2.627, 95% CI: 1.305-5.980, P = 0.019). In the UUC subgroup, the average change in estimated glomerular filtration rate (eGFR) decreased in the RNU group (-11.2 ± 17.8 mL/min/1.73 m2), while in the KSS group, it showed a slight increase (3.1 ± 7.9 mL/min/1.73 m2; P < 0.000). After 1:1 propensity score matching of the UUC subgroup into RNU (N = 50) and KSS (N = 50) groups, there was no significant difference in survival rates between the two surgical methods. Among the patients with PUC who underwent RNU (N = 292), the number of patients with UUC, excluding those with a single kidney (N = 2), CKD stage 4 or below (N = 15), contralateral renal function (CRF) ≥50 mL/min/1.73 m2 and ipsilateral renal function (IRF) <30 mL/min/1.73 m2 (N = 72), was 152 (52.1%). There were 28 patients with CRF ≥50 mL/min/1.73 m2 and IRF ≥30 mL/min/1.73 m2, 59 patients with CRF <50 mL/min/1.73 m2 and IRF <30 mL/min/1.73 m2, and 35 patients with CRF <50 mL/min/1.73 m2 and IRF ≥30 mL/min/1.73 m2.

Conclusions For ureter cancer patients with single kidneys, CKD stage 4 or below, bilateral tumors, or high surgical morbidity, KSS is the initial recommendation. When CRF is ≥50 mL/min/1.73 m2 and IRF is <30 mL/min/1.73 m2, RNU is proactive. If CRF is <50 mL/min/1.73 m2 and IRF is ≥30 mL/min/1.73 m2, KSS may be recommended to enhance the likelihood of adjuvant chemotherapy. The decision between RNU and KSS should take into consideration tumor characteristics, clinical staging, and patient preferences for kidney preservation.