The primary objective is to determine if 3D modelling shortens total console operation time as a surrogate endpoint for clinical outcomes like perioperative complications and morbidity in robotic-assisted partial nephrectomy.

3DPN is a prospective, multicentre, randomised, controlled, two-armed, open trial to compare the 3D modelling with the 2D modelling in robotic-assisted partial nephrectomy. According to the randomisation the 3D or 2D modelling is used for patient information (before intervention) and for partial nephrectomy. A six-month follow-up visit is provided.

Inclusion Criteria:

• Patients with kidney tumours ≤ 7cm and planned robotic-assisted partial nephrectomy with the DaVinci Surgical System
• CT scan with contrast medium available
• Age ≥ 18 years
• Written informed consent

Exclusion Criteria:

• History of surgery on affected kidney (e.g., partial nephrectomy, pyeloplasty, kidney cyst deroofing, percutaneous nephrolitholapaxy, radiofrequency ablation)
• Clinical suspicion of metastases (stage cN1/cM1)
• Horseshoe kidney
• Previous malignancy with ongoing or planned nephrotoxic chemotherapy
• Multifocal kidney tumour
• Von Hippel-Lindau syndrome and other hereditary kidney cancer syndromes
• Patient is immunosuppressed (e.g., organ transplantation, leukaemia)
• Tumor thrombus in Vena renalis or Vena cava inferior
• Severe cognitive impairment
• Pregnancy or lactation or women with desire for children
• Patients under legal supervision or guardianship
• Unable to give informed consent or suspected lack of compliance
• Patients who decline data collection and storage for the main study

According to the recommendations on data sharing by the International Committee of Medical Journal Editors (ICMJE) data resulting from the 3DPN trial will be made available to the scientific community.

After publication of the major results

After publication of the major results and upon reasonable request from researchers performing an individual patient data meta-analysis, individual patient data that underlie published results will be shared after de-identification.

This requires approval by the local Institutional Review Board (IRB) of the researcher requesting the data along with public registration of the metaanalysis.

Summary statistics that go beyond the scope of published material will be made available to researchers for meta-analysis upon reasonable request and if the necessary data analysis is not unduly time-consuming. Together with publication of the main results, the trial protocol in full will be made publicly available as well as the statistical analysis plan.