Objectives: Mayo adhesive probability (MAP) score quantifies adherent perinephric fat (APF) and is associated with the prolongation of surgery duration or the increase of surgical complication rates.
Patients and methods: In this study, 311 patients who underwent robot-assisted partial nephrectomy (RAPN) at our institute were included. APF was quantified using the MAP score calculated using perinephric fat thickness and stranding seen on a preoperative enhanced CT scans. The surgery duration was classified into the dissection (robotic manipulation to hilar clamping) and resection (hilar clamping to robotic surgery completion) phases.
Results: The MAP score was found to be 0, 1, 2, 3, 4, and 5 in 98 (32%), 86 (28%), 21 (7%), 48 (15%), 44 (14%), and 14 (4%) patients, respectively. The dissection and resection phase times increased with an increase in the MAP score. The median dissection phase times for MAP scores of 0, 1, 2, 3, 4, and 5 were 71.7, 79.1, 88.9, 97.0, 99.7, and 118.8 minutes, respectively. The MAP score was more strongly associated with the prolongation of the dissection phase than with the prolongation of the resection phase. In multivariate analysis for dissection phase time of more than 90 minutes, the body mass index [odds ratio (OR) = 1.09, p = 0.0209], early surgical experience (first 100 cases) (OR = 2.32, p = 0.0024), and MAP score ≥3 (OR = 6.20, p < 0.0001) significantly associated with the prolongation of dissection phase in a logistic regression model.
Conclusions: The MAP score is a factor significantly associated with the prolongation of the dissection phase during RAPN.
Keywords: MAP score; RAPN; operation time; partial nephrectomy; robotic surgery.