Goßler Christopher, May Matthias, Rosenhammer Bernd, Breyer Johannes, Stojanoski Gjoko, Weikert Steffen, Lenart Sebastian, Ponholzer Anton, Dreissig Christina, Burger Maximilian, Gilfrich Christian, Bründl Johannes
Department of Urology, Caritas St. Josef Medical Centre, University of Regensburg, Regensburg, Germany.
Department of Urology, St. Elisabeth Hospital Straubing, Brothers of Mercy Hospital, Straubing, Germany.
Cent European J Urol. 2020;73(4):457-465. doi: 10.5173/ceju.2020.0265.R1. Epub 2020 Dec 3.
Current results concerning the effect of body mass index (BMI) on positive surgical margins (PSMs) after robot-assisted radical prostatectomy (RARP) in patients with localized prostate cancer are inconsistent. Therefore, the aim of this study was to further analyse the association between BMI and PSMs after RARP.
Between March 2017 and December 2017 a multicentre, prospective, randomised, single-blind series with a blinded outcome assessment of 232 RARP patients was performed. Multivariate logistical regression models were used to analyse the independent effect of obesity, with body-mass-index (BMI) dichotomised at 30 kg/m (model-1) and at 90 percentile (model-2), on PSMs.
Median BMI was 27.2 kg/m, PSMs were found in 15.5% (n = 36). In multivariate model-1, obesity did not have a significant effect on PSMs (OR 2.34, p = 0.061). However, if BMI was dichotomized at the 90 percentile (BMI ≥33.7 kg/m²), patients with a higher BMI showed PSMs four-times more frequently (OR 3.99, p = 0.013). In both models, preoperative prostate-specific antigen (PSA) levels and pathological tumour stage had a significant effect on PSMs. There was no significant correlation between BMI and the extent of PSMs, nor a significant difference between the BMI groups and the localisation of PSMs. There was a higher percentage of posteriolateral PSM localisation in obese patients compared to patients with a BMI of less than 30 kg/m (58.3% and 25.3% of the localisations were posterolateral in obese and non-obese patients, respectively), however this effect was not statistically significant (p = 0.175).
In addition to a longer operation time and about twice as many complications, patients with a BMI of ≥33.7 kg/m² had a higher PSM rate after RARP. Differences in localization of PSMs in relation to obesity should be evaluated in future research.
目前关于体重指数（BMI）对局限性前列腺癌患者机器人辅助根治性前列腺切除术（RARP）后手术切缘阳性（PSM）影响的研究结果并不一致。因此，本研究的目的是进一步分析RARP术后BMI与PSM之间的关联。
2017年3月至2017年12月，对232例RARP患者进行了一项多中心、前瞻性、随机、单盲系列研究，并对结果进行了盲法评估。采用多变量逻辑回归模型分析肥胖的独立影响，将体重指数（BMI）分为30kg/m²（模型1）和第90百分位数（模型2），分析其对PSM的影响。
BMI中位数为27.2kg/m²，发现36例（15.5%）患者出现PSM。在多变量模型1中，肥胖对PSM没有显著影响（OR 2.34，p = 0.061）。然而，如果将BMI分为第90百分位数（BMI≥33.7kg/m²），BMI较高的患者出现PSM的频率高出四倍（OR 3.99，p = 0.013）。在两个模型中，术前前列腺特异性抗原（PSA）水平和病理肿瘤分期对PSM有显著影响。BMI与PSM范围之间无显著相关性，BMI组与PSM定位之间也无显著差异。与BMI小于30kg/m²的患者相比，肥胖患者后外侧PSM定位的百分比更高（肥胖和非肥胖患者的定位分别有58.3%和25.3%为后外侧），然而这种影响在统计学上并不显著（p = 0.175）。
除了手术时间延长和并发症多出约一倍外，BMI≥33.7kg/m²的患者在RARP术后PSM发生率更高。未来的研究应评估肥胖与PSM定位差异之间的关系。
