中老年肾癌患者内脏型肥胖与肿瘤分级的关系

Association between Visceral Obesity and Tumor Grade in Middle-aged and Elderly Patients with Renal Cell Carcinoma

目的探讨中老年肾癌患者内脏型肥胖与肿瘤病理学分级的相关性。方法回顾性分析2009年1月至2014年9月北京大学人民医院278例经病理证实的中老年(年龄≥50岁)肾癌患者资料。采用术前脐平面CT平扫进行内脏脂肪、皮下脂肪和总脂肪含量测定。内脏型肥胖以内脏脂肪占总脂肪的百分比表示。应用Logistic回归分析方法进行统计学分析,评估临床常用指标及肥胖评估指标与高级别肾癌风险肿瘤分级的相关性。结果 278例肾癌患者中,29例(10.43%)为高级别肿瘤。与低级别肿瘤组相比,高级别肿瘤组内脏型肥胖患者比例较高[(47.80±8.33)%比(43.24±10.24)%,P=0.022],肿瘤直径较大[(5.42±2.99)cm比(4.11±2.27)cm,P=0.021],但体质量指数、总脂肪含量、内脏脂肪含量和皮下脂肪含量在两组间无明显差异。Logistic回归分析结果提示,内脏型肥胖与较高的肿瘤分级相关(OR=1.045,95%CI:1.002~1.090,P=0.042)。亚组分析结果显示,在进展性肾癌和肿瘤直径较大(>4 cm)的病例中,内脏型肥胖与肿瘤分级相关(OR=1.131,95%CI:1.017~1.256,P=0.023;OR=1.061,95%CI:1.005~1.121,P=0.032),而在局限性肾癌和肿瘤直径较小(≤4 cm)的病例中未观察到该现象。结论在中老年肾癌患者中,尤其是进展性肾癌和肿瘤直径较大的患者中,内脏型肥胖与肿瘤分级相关,内脏型肥胖可能是高级别肾癌的危险因素。

Objective In this retrospective study,we investigated whether visceral obesity is associated with Fuhrman grade in middle-aged and elderly patients with renal cell carcinoma. Methods Medical records of 278 middle-aged and elderly patients who underwent radical or partial nephrectomy at Peking University People’s Hospital from January 2009 to September 2014 were retrospectively reviewed. The quantities of visceral ,subcutaneous and total adipose tissue were measured with pre-operative computed tomography scans at the level of umbilicus. Visceral obesity was indicated by the percentage of visceral adipose tissue. The logistic regression analysis was used to determine the risk factor of high grade disease （ Fuhrman grade Ⅲ or Ⅳ）. Results A total of 29 （10. 43%） tumors were classified as high-grade disease. Patients in high-grade group were found to have a higher percentage of visceral adipose tissue （ P =0. 022） and a larger tumor size （ P = 0. 021）. However, body mass index, total adipose tissue, visceral adipose tissue, and subcutaneous adipose tissue were comparable between low-grade and high-grade groups. The result of logistic analysis showed that visceral obesity was associated with high-grade tumors （ OR = 1. 045 , 95% Cl： 1. 002-1. 090, P = 0. 042）. In the subgroup analysis, the percentage of visceral adipose tissue was associated with Fuhrman grade in advanced patients （ OR =1.131, 95% CI： 1.017-1.256, P =0.023） or patients with a larger tumor （ OR =1.061, 95% CI： 1. 005-1. 121, P = 0. 032） , but not in patients with an organ-confined disease or a smaller tumor. Conclusions Visceral obesity was associated with higher Furhman grade in middle-aged and elderly patients with renal cell carcinoma, especially in patients with an advanced disease or a larger tumor. Vesceral obesity may be the risk factor of high-grade renal cell carcinoma.