Predicting Adherent Perinephric Fat Using Preoperative Clinical and Radiological Factors in Patients Undergoing Partial Nephrectomy.

BACKGROUND: The decision to perform a partial nephrectomy (PN) relies largely upon the complexity of the renal mass and its surrounding anatomy. The presence of adherent perinephric fat (APF) can increase surgical complexity and extend operative times. The accurate prediction of APF may improve surgical planning and aid in decision making for the surgical approach. OBJECTIVE: We sought to develop and externally validate a score that predicts APF based on preoperative clinical and radiological prognostic factors. DESIGN, SETTING, AND PARTICIPANTS: We retrospectively analyzed 495 consecutive patients who underwent open or minimally invasive PN. APF was defined as the presence of "dense," "adherent," or "sticky" perinephric fat at the time of dissection by the surgeon, and this did not require subcapsular dissection. Additionally, we analyzed an independent cohort of 285 patients for external validation. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: A score model was developed using multivariate logistic regression analysis. Calibration of the fitted model was assessed graphically with a plot of the predicted versus the actual probability of APF, and discrimination was assessed by calculating the area under the receiver operating characteristic curve. RESULTS AND LIMITATIONS: Of the 495 patients, 95 (19%) had APF. Patients with APF had longer operative (p=0.02) and arterial clamp (p=0.01) times than non-APF patients. On multivariate analyses, diabetes mellitus (p=0.009), posterior perinephric fat thickness (p<0.001), and perinephric stranding (p<0.001) were predictors of encountering APF in PN. A risk score ranging from 0 to 4 was developed based on these three variables to predict APF. The scoring system demonstrated good discrimination of 0.82 and 0.84 for the development and external validation cohorts, respectively. CONCLUSIONS: The APF score can accurately predict the presence of APF in patients with a small renal mass who are planning to undergo PN. This score could aid in pre- and intraoperative planning and impact the surgical approach. PATIENT SUMMARY: The presence of "sticky" fat surrounding the kidney in patients undergoing partial nephrectomy has previously been linked to longer operative times, intraoperative complications, and surgical conversion. In our study, we found that this feature is more often presented in patients with diabetes mellitus, and thicker and more inflammatory fat on renal imaging. Based on these findings, we developed a risk score that can accurately predict this feature before surgery, in order to improve surgical planning and better counsel the patients.

18F-Fluciclovine Uptake in a Ureterocele.

A 60-year-old man with prostate adenocarcinoma status post radical prostatectomy and bilateral pelvic lymph node dissection referred for restaging F-fluciclovine PET/CT due to rising serum prostate-specific antigen levels (1.1 ng/mL at that time of imaging). PET/CT images were obtained from the proximal thighs to the vertex of the skull approximately 3 to 5 minutes after the IV administration of 347.8 MBq (9.4 mCi) of F-fluciclovine. PET/CT imaging demonstrated a focus of abnormally increased F-fluciclovine uptake at the right ureterovesical junction. Subsequent MRI of the pelvis revealed that this focus corresponded to a benign ureterocele.

Cytoreductive nephrectomy for metastatic renal cell carcinoma.

The incidence of renal cell carcinoma is increasing, with up to one-third of patients presenting with metastatic disease. Combination therapy is used to prolong survival in patients with metastatic renal cell carcinoma, which carries a poor prognosis. Although two pivotal phase 3 trials have demonstrated the efficacy of immunotherapy after cytoreductive nephrectomy for metastatic disease, for now, targeted therapy has replaced immunotherapy as the preferred systemic treatment in these patients. Two ongoing phase 3 trials are evaluating the role of cytoreductive nephrectomy prior to targeted therapy. Proper patient selection is paramount in achieving successful outcomes.