Editorial Comment for Tatsugami et al.

T he surgical management of renal tumors has undergone significant improvement in the last two decades with an increasing number of nephron-sparing surgeries being undertaken. Specialist centers now undertake partial nephrectomy for technically challenging cases such as solitary kidney, T_1b tumors, and tumours near the hilum. As the surgical techniques have been refined within the confines of good oncologic outcome, the importance of ischemic time has become the mainstay in deciding the nuances of surgical technique and the expected long-term renal recovery.

Godoy and associates ¹ and Bhayani and colleagues ² have suggested that warm ischemia times of ≤ 55 minutes are safe and effective. Other studies, ^{3 –5} however, dispute this and suggest that warm ischemia should be limited to < 20 minutes. The Mayo and Cleveland groups suggest that longer warm ischemic effects were masked by the normal contralateral kidneys in such patients. ⁵ Cold ischemia has been deemed superior and considered imperative when warm ischemia time is expected to be > 30 minutes. In the last decade, laparoscopic partial nephrectomy has raised many questions concerning the superiority of different surgical approaches and mode of ischemia.

Tatsugami and coworkers have dealt with this complex question. The small numbers, short follow-up, and nonstandardized patient selection hamper the quality of the study. Despite the inherent bias in patient selection, the authors have reported some interesting results. They have reported that cold ischemia of up to 55 minutes was still compatible with renal function preservation. The studies to date have used serum creatinine level and/or glomerular filtration rate to quantify renal function. The comparative renal scintigraphy gives a more accurate renal function study, as evidenced in this study.

Retroperitoneal laparoscopic partial nephrectomy should be considered as the best possible approach for patients who are identified for laparoscopic partial nephrectomy, taking into consideration the need for advanced laparoscopic skills and potential technical challenges. Robot-assisted partial nephrectomy is another safe and feasible surgical option. ⁶