Anatomical landmark-based proportional coordinate localization in laparoscopic partial nephrectomy for completely endophytic renal tumors.

BACKGROUND

Accurate localization of completely endophytic renal tumors remains challenging in laparoscopic partial nephrectomy, and conventional intraoperative ultrasonography is experience-dependent.

OBJECTIVE

To evaluate an intraoperative localization technique based on AI-assisted three-dimensional reconstruction and an anatomical landmark-based proportional coordinate system (XYZ).

METHODS

We retrospectively analyzed 105 patients treated from May 2016 to July 2025. Patients were assigned to the XYZ coordinate-guided localization group (n = 52), using preoperative three-dimensional planning, calculation of the proportional XYZ coordinates, and intraoperative ultrasonographic verification, or the traditional localization group (n = 53), using conventional imaging and intraoperative ultrasonographic scanning. Localization efficiency, perioperative outcomes, and trifecta achievement were compared.

RESULTS

Baseline characteristics were comparable. Compared with the traditional localization group, the XYZ coordinate-guided localization group had shorter localization time (225.5 s vs 317.0 s, p < 0.001), higher first-attempt localization success rate (59.62% vs 37.74%, p = 0.025), shorter warm ischemia time (21.73 min vs 27.19 min, p < 0.001), and higher trifecta achievement rate (61.54% vs 24.52%, p < 0.001). Estimated blood loss was lower (105.0 mL vs 130.0 mL, p = 0.035), blood transfusion tended to be reduced (3.85% vs 16.98%, p = 0.052), and acute kidney injury was less frequent (11.54% vs 28.30%, p = 0.032). Multivariable regression confirmed XYZ coordinate-guided localization group was associated with higher odds of achieving the trifecta and shorter warm ischemia time.

CONCLUSION

In the present study, XYZ coordinate-guided localization was associated with shorter intraoperative localization and warm ischemia times and a higher rate of achieving the trifecta than traditional localization. We will conduct prospective multicenter studies to further evaluate its effectiveness and generalizability.