RCC, Renal Cell Cancer
Conditions
Keywords
Partial Nephrectomy, Robot-assisted, MEDULLARY SUTURE, MEDULLARY-ONLY SUTURE
Brief summary
Renal function preservation is a growing concern in the surgical management of kidney tumors, particularly with the rise in chronic kidney disease worldwide. Recent surgical innovations have focused on modifying renorrhaphy techniques to minimize renal damage. Emerging evidence suggests that omitting cortical suturing may reduce operative time, blood loss, and renal parenchymal loss without increasing major complications. This randomized controlled trial aims to compare outcomes between medullary-only and combined cortical-medullary suture techniques during robot-assisted partial nephrectomy, with the goal of identifying the approach that best balances functional preservation and surgical safety.
Detailed description
To investigate the clinical impact of a potentially modifiable surgical variable, namely, the choice of suture technique during renal reconstruction, on patient outcomes following robot-assisted partial nephrectomy. The preservation of renal function has become a central concern in the surgical management of renal tumors, especially given the long-term consequences of chronic kidney disease on patient morbidity and mortality. Partial nephrectomy is preferred for localized renal masses as it allows for oncologic control while maintaining renal function. Traditionally, renorrhaphy involves a two-layer closure including both medullary and cortical sutures. However, recent literature suggests that omitting the cortical suture may reduce renal parenchymal volume loss and warm ischemia time, while possibly introducing a higher rate of minor complications. Despite growing interest in minimally invasive nephron-sparing techniques, robust prospective and randomized trials directly comparing single-layer (medullary-only) and double-layer (cortical and medullary) renorrhaphy remain scarce. The single-layer technique, first proposed to address concerns over unnecessary cortical compression and ischemic injury, is gaining attention for its simplicity and potential advantages in reducing blood loss and operative time. This trial aims to evaluate whether avoiding cortical suturing during robot-assisted partial nephrectomy leads to improved postoperative renal function, reduced blood loss, and shorter surgical duration. Patients will be randomly assigned to undergo either medullary-only renorrhaphy or the conventional dual-layer approach. Both techniques will be assessed for their effect on warm ischemia time, complication rates, renal volume loss, and surgical efficiency. The study will enroll 80 patients undergoing partial nephrectomy for renal masses, distributed evenly across the two intervention groups. This sample size was calculated to ensure statistical power to detect differences in estimated blood loss, the primary outcome. A broad range of secondary outcomes will be measured at multiple postoperative time points, including estimated glomerular filtration rate, renal volume, incidence of surgical complications, and quality of life indicators. By employing a randomized, prospective, and blinded design, the trial seeks to minimize bias and deliver high-quality evidence to guide future surgical decision-making. Ultimately, the study aims to clarify whether cortical renorrhaphy can be safely omitted without compromising patient outcomes, potentially simplifying surgical technique and improving recovery profiles in this patient population.
Interventions
PROCEDUREMedullary-only suturing (single-layer)
Only the base layer (medulla) is sutured after tumor excision, Cortical suturing is omitted. Hemostatic agents are applied.
DEVICESuture
Synthetic absorbable monofilament suture (Caproyl™ 3-0).
PROCEDUREMedullary and cortical suturing (two-layer)
Both medullary and cortical layers are sutured after tumor excision, Performed with robotic assistance using absorbable sutures. Hemostatic agents are applied
DEVICEHemostatic Agent
Hemostatic agents (e.g., Bleed Stp Plus, Surgicel® Fibrillar, Hemopatch®).
Sponsors
Brazilian Institute of Robotic Surgery
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
The blinding protocol will include the patient, the physician responsible for patient selection, the physician overseeing postoperative care, the professional conducting follow-up consultations, the students involved in collecting clinical follow-up data, and the team responsible for statistical analysis. However, the surgical team and the operating surgeon will not be blinded, nor will the students responsible for collecting intraoperative data.
Intervention model description
The first group will undergo medullary-only suturing (single-layer) using 3-0 diameter synthetic absorbable monofilament poliglecaprone 25 suture (Caprofyl™), with early unclamping performed robotically. In the second group, both medullary and cortical suturing (two-layer) will be performed, using 3-0 Caprofyl™ for the medullary suture and, after early unclamping, 0-diameter braided synthetic absorbable polyglycolic suture (Vicryl™) for the cortical layer, also robotically assisted. If the surgeon deems it necessary to perform a second suture using Vicryl™ 0 in the first group after unclamping, it will be carried out, and the surgeon's reasoning will be documented. These patients will be analyzed separately in order to identify predictive factors for such a change. Hemostatic agents will be used in all groups.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Diagnosis of renal mass confirmed by computed tomography (CT) or magnetic resonance imaging (MRI) * Indication for partial nephrectomy * Written informed consent * Expected survival of at least 6 months * Eastern Cooperative Oncology Group (ECOG) score performance status ≤ 1 * Negative serum or urine pregnancy test within 24 hours before surgery for women of childbearing potential * Recovery from any prior therapy-related toxicity to grade 1 or better * If a biopsy has been performed, pathology consistent with renal cell carcinoma (RCC)
Exclusion criteria
* Solitary kidney * Multiple or bilateral renal masses if more than one mass is operated on simultaneously or within less than 4 months * Hepatic or renal toxicity grade ≥ 2 with glomerular filtration rate (GFR) \< 30 according to Common Terminology Criteria for Adverse Events (CTCAE v4) * Bleeding diathesis * Inability to maintain anticoagulation for surgery * Participation in another experimental trial simultaneously or within 30 days prior to enrollment * Significant acute or chronic medical, neurological, or psychiatric condition that could compromise safety, limit study completion, or impair study objectives in the opinion of the Principal Investigator
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Estimated Blood loss | Perioperative/Periprocedural time | Estimated blood loss, assessed to compare renorrhaphy techniques (single medullary suture vs. combined medullary and cortical suture) during partial nephrectomy. The volume, recorded in milliliters, was measured using a graduated collection canister connected to the assistant surgeon's suction device, with correction for the amount of saline solution instilled into the cavity. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in estimated glomerular filtration rate (eGFR) | 1 day, 2 weeks, 2 months, and 5 months | Difference in eGFR values calculated using the CKD-EPI formula between baseline (preoperative) and postoperative time points |
| Percentage renal volume loss | 4 months | Percentage reduction in renal parenchymal volume calculated from CT scan measurements at 4 months compared with baseline preoperative volume. |
| Warm ischemia time | Perioperative/Periprocedural time | Duration, in minutes, of arterial clamping recorded during partial nephrectomy |
| Participants requiring intraoperative conversion | Perioperative/Periprocedural time | Number of participants converted to open or radical nephrectomy during the procedure. |
| Console time | Perioperative/Periprocedural time | Time in minutes from docking to undocking of the robotic system. |
| Length of hospital stay | From the date of surgery until the date of hospital discharge, assessed up to 30 days postoperatively | Number of days from the date of surgery until the date of hospital discharge. |
| Participants with intraoperative or postoperative complications | Through 5 months | Number of participants experiencing complications such as hematuria, pseudoaneurysm, or urinary fistula, graded according to the Clavien-Dindo classification. |
Countries
Brazil
Contacts
Primary ContactNilo J Leão, MD.
Backup ContactFelipe P Albuquerque, MD.
Outcome results
None listed