Zihao Li, Li Wang, Chunzhi Qi, Hongliang Li, Tie Chong, Zhenlong Wang
The proposed "danger zone" concept offers an exploratory anatomical tool to assist in the preoperative risk assessment of T1 hilar tumors. Initial data suggest that LPN remains a viable option for lesions located outside the danger zone. When tumors invade the danger zone, LRN provides a safer perioperative course at the expense of functional preservation, whereas oncological efficacy seems equivalent between modalities. These preliminary observations necessitate rigorous prospective validation prior to clinical application.
BACKGROUND: Laparoscopic partial nephrectomy (LPN) is a preferred surgical approach for early-stage renal cell carcinoma. However, there is ongoing debate regarding the optimal surgical technique for highly complex renal hilar tumors. Moreover, long-term follow-up data assessing the applicability and outcomes of LPN for renal hilar tumors remain limited.
METHODS: A retrospective analysis was conducted on patients with pT1-stage clear cell renal cell carcinoma (ccRCC). We proposed an imaging-based "danger zone" defining the critical boundary of hilar vascular structures. Based on spatial location and surgical approach, patients were stratified into 4 groups: non-hilar partial nephrectomy (NHPN), hilar partial nephrectomy outside (HPNOUT) or inside (HPN-IN) the danger zone, and hilar radical nephrectomy (HRN). We compared perioperative parameters, postoperative renal function (eGFR), and recurrence-free survival (RFS) across these cohorts.
RESULTS: A total of 323 patients were included (NHPN, n = 204; HPNOUT, n = 46; HPN-IN, n = 21; HRN, n = 52). Over a median follow-up of 3,276 days, 24 overall oncologic events were recorded. The HPNOUT group demonstrated perioperative outcomes, postoperative eGFR, and RFS (HR = 1.16, 95% CI: 0.28-4.85, P = 0.836) comparable to the NHPN cohort. Conversely, the HPN-IN group exhibited significantly higher estimated blood loss (adjusted difference: +136.3 ml, 95% CI: 99.2-173.4, P < 0.001) compared to the HPNOUT group. However, when evaluating tumors exclusively within the danger zone, a distinct clinical trade-off emerged. Compared to HRN, the HPN-IN group experienced greater perioperative morbidity but achieved significantly superior long-term renal function preservation (across 3-month, 1-year, and 5-year follow-ups; all P < 0.05). Importantly, long-term oncological control remained comparable between these 2 approaches (RFS HR = 2.06, 95% CI: 0.60-7.09, P = 0.250).
CONCLUSIONS: The proposed "danger zone" concept offers an exploratory anatomical tool to assist in the preoperative risk assessment of T1 hilar tumors. Initial data suggest that LPN remains a viable option for lesions located outside the danger zone. When tumors invade the danger zone, LRN provides a safer perioperative course at the expense of functional preservation, whereas oncological efficacy seems equivalent between modalities. These preliminary observations necessitate rigorous prospective validation prior to clinical application.