Introduction: For some renal tumors, the indication to nephron sparing surgery (NSS) becomes imperative, such as chronic kidney disease (CKD) and bilateral tumours. For these patients three-dimensional virtual models (3DVMs) assistance could allow to reshape the surgical strategy, considering the anatomy of the organ in a perspective of postoperative real organ functioning instead of focusing the surgery on the tumor excision alone.
Methods: Three patients with high complexity renal masses, with abnormal anatomy and imperative indication to NSS were selected. All patients performed contrast-enhanced CT from which a 3DVM was obtained. Using such technological tools, it was possible to set the surgical strategy considering the anatomical kidney details, leading the surgeon to plan the sacrifice of the upper portion of the whole organ in light of its irrelevant contribution to the postoperative global renal function even if spared.
Results: Two out of three patients harbored bilateral renal tumors. The third patient presented a renal mass in the left kidney and a contralateral renal hypoplasia (right split renal function of 25%). All of them demonstrated similar anatomical and tumoral features, with a potential independent vascularization and drainage for the lower pole. In one of them the upper pole of the kidney was spared, exiting in an hydrocalyx functionally excluded, while in the other two cases it was removed together with the lesion. The spared portion of the kidney-maintained vascularization, as demonstrated by intraoperative ultrasound and indocyanine green injection.
Conclusions: 3DVMs, especially in case of complex renal masses with imperative indication to NSS, allow to plan the surgical strategy on the basis of the anatomical characteristics of the organ in which the tumor grows, focusing the attention on the effective functional gain of the surgery, even considering sacrificing portions of the organ technically preservable but functionally not useful.