Analyzing National Incidences and Predictors of Open Conversion During Minimally Invasive Partial Nephrectomy for cT1 Renal Masses

Preparing for the Worst: Management and Predictive Factors of Open Conversion During Minimally Invasive Renal Tumor Surgery (UroCCR-135 Study)

Background and objective

Data regarding open conversion (OC) during minimally invasive surgery (MIS) for renal tumors are reported from big databases, without precise description of the reason and management of OC. The objective of this study was to describe the rate, reasons, and perioperative outcomes of OC in a cohort of patients who underwent MIS for renal tumor initially. The secondary objective was to find the factors associated with OC.

Methods

Between 2008 and 2022, of the 8566 patients included in the UroCCR project prospective database (NCT03293563), who underwent laparoscopic or robot-assisted minimally invasive partial (MIPN) or radical (MIRN) nephrectomy, 163 experienced OC. Each center was contacted to enlighten the context of OC: "emergency OC" implied an immediate life-threatening situation not reasonably manageable with MIS, otherwise "elective OC". To evaluate the predictive factors of OC, a 2:1 paired cohort on the UroCCR database was used.

Key findings and limitations

The incidence rate of OC was 1.9% for all cases of MIS, 2.9% for MIRN, and 1.4% for MIPN. OC procedures were mostly elective (82.2%). The main reason for OC was a failure to progress due to anatomical difficulties (42.9%). Five patients (3.1%) died within 90 d after surgery. Increased body mass index (BMI; odds ratio [OR]: 1.05, 95% confidence interval [CI]: 1.01-1.09, p = 0.009) and cT stage (OR: 2.22, 95% CI: 1.24-4.25, p = 0.008) were independent predictive factors of OC.

Conclusions and clinical implications

In MIS for renal tumors, OC was a rare event (1.9%), caused by various situations, leading to impaired perioperative outcomes. Emergency OC occurred once every 300 procedures. Increased BMI and cT stage were independent predictive factors of OC.

Patient summary

The incidence rate of open conversion (OC) in minimally invasive surgery for renal tumors is low. Only 20% of OC procedures occur in case of emergency, and others are caused by various situations. Increased body mass index and cT stage were independent predictive factors of OC.

Role and Utility of Mixed Reality Technology in Laparoscopic Partial Nephrectomy: Outcomes of a Prospective RCT Using an Indigenously Developed Software

Objective

To develop a software for mixed reality (MR) anatomical model creation and study its intraoperative clinical utility to facilitate laparoscopic partial nephrectomy.

Materials and Methods

After institutional review board approval, 47 patients were prospectively randomized for LPN into two groups: the control group (24 patients) underwent operation with an intraoperative ultrasound (US) control and the experimental group (23 patients) with smart glasses HoloLens 2 (Microsoft, Seattle, WA, USA). Our team has developed an open-source software package called “HLOIA,” utilization of which allowed to create and use during surgery the MR anatomical model of the kidney with its vascular pedicle and tumor. The study period extended from June 2020 to February 2021 where demographic, perioperative, and pathological data were collected for all qualifying patients. The objective was to assess the utility of a MR model during LPN and through a 5-point Likert scale questionnaire, completed by the surgeon, immediately after LPN. Patient characteristics were tested using the chi-square test for categorical variables and Student's t-test or Mann–Whitney test for continuous variables.

Results

Comparison of the variables between the groups revealed statistically significant differences only in the following parameters: the time for renal pedicle exposure and the time from the renal pedicle to the detection of tumor localization (p < 0.001), which were in favor of the experimental group. The surgeon's impression of the utility of the MR model by the proposed questionnaire demonstrated high scores in all statements.

Conclusions

Developed open-source software “HLOIA” allowed to create the mixed reality anatomical model by operating urologist which is when used with smart glasses has shown improvement in terms of time for renal pedicle exposure and time for renal tumor identification without compromising safety.

Conversion to Open Radical or Partial Nephrectomy Associated with Unplanned Hospital Readmission After Attempted Minimally Invasive Approach

Introduction/Objectives: We endeavored to explore the rates of unplanned hospital readmission (UHR) in patients who underwent minimally invasive radical or partial nephrectomy who were subsequently converted to open surgery. Patients and Methods: The National Cancer Database (NCDB) was used for this study. Patients diagnosed with renal cancer and who had minimally invasive partial or radical nephrectomy from 2004 to 2016 were included in the study. Patients were categorized as converted or not converted to open surgery. UHR was the outcome of the study and was defined as UHR within 30 days of discharge. We conducted a one-to-one nearest-neighbor propensity-score matching using baseline clinical, tumor, and facility characteristics. To evaluate the relationship between conversion to open surgery and UHR, we conducted a multivariable logistic regression on the propensity-matched cohort, a propensity score-matched model without controlling for any covariate, and a propensity score-adjusted model, controlling for only the propensity score. Results: A total of 142,040 patients were identified, with a 2.98% conversion rate. There was an overall decrease in the rate of conversion to open surgery from 2010 (4.11%) to 2016 (2.43%). Laparoscopic radical nephrectomy remained a significant contributor to the rate of conversion (at least 50% per year). In the unmatched cohort, the UHR rate was higher among those who had a conversion to open surgery (n = 710, 0.52% versus n = 44, 1.04%; P < .001). Similarly, in the propensity score-matched cohort, the UHR rate was higher among those who had a conversion to open (n = 22, 0.52% versus n = 44, 1.04%; P = .007). After controlling for other factors, conversion to open remained independently associated with UHF. Conclusion: Conversion to open radical or partial nephrectomy from a minimally invasive approach is independently associated with an increased risk of 30-day UHR.

Strengths and Limitations of Registries in Surgical Oncology Research

Over the past two decades, there has been a dramatic increase in studies based on large multi-institutional tumor registries. Applications of such databases span various research themes including epidemiology, oncology, surgical techniques, perioperative outcomes, and prognosis. Although these databases are acquired relatively easily, offer larger sample sizes and improved generalizability compared with institutional data, acknowledging limitations within analysis and cautious interpretation of data is important. Questionable conclusions can result when insufficient attention is paid to issues such as data quality and depth, potential sources of bias and missing data. This article reviews research themes and important limitations of these databases. The contemporary reporting of these issues in the literature and an increased awareness among surgical oncologists of potential applications and limitations will ensure that studies in the surgical oncology literature achieve high standards of methodological quality and clinical utility.