Li Quan-Lin, Guan Hong-Wei, Zhang Qiu-Ping, Zhang Li-Zhi, Wang Fa-Peng, Liu Yong-Ji
Department of Urology, First Affiliated Hospital of Dalian Medical University, 222 Zhongshan Road, Dalian 116011, People's Republic of China.
Eur Urol. 2003 Oct;44(4):448-51. doi: 10.1016/s0302-2838(03)00310-5.
Renal cell carcinoma (RCC) of 4 cm or less is with a low incidence of multicentricity and metastasis and is usually considered suitable for nephron-sparing surgery (NSS). This study was designed to investigate the distance between extra-pseudocapsule cancer lesions and primary tumors, and to suggest the optimal margin of normal parenchyma in NSS for RCC 4 cm or less.
We prospectively studied 82 kidneys in which RCCs of 4 cm or less were resected by radical nephrectomy. According to UICC TNM classification (1997), all tumors were staged as T1 and classified as conventional RCC in 76 cases and papillary RCC in 6 cases. The kidney samples were first step sectioned at 3mm intervals and examined for multicentricity. Then, on each layer of tissue sectioned, parenchyma margins of 15 mm beyond pseudocapsule were continuously sectioned and examined microscopically to investigate completeness of pseudocapsule and possible presence of extra-pseudocapsule cancer lesions. The greatest distance between extra-pseudocapsule lesions and primary tumors was measured.
The diameter of 82 primary tumors was 3.4+/-0.7 mm (range 1.5-4.0 cm). Of them, 31.7% (26/82) were found without intact pseudocapsule. Of the 82 cases, 19.5% (16/82) were with positive cancer lesions beyond pseudocapsule, with invasion into normal parenchyma in 12.2% (10/82), into venule in 2.4% (2/82) and satellite tumors in 4.9%(4/82). The average distance between extra-pseudocapsule cancer lesions and primary tumors was 0.5+/-1.3mm (range 0-5.0mm), with a 95% confidential interval (CI) (0.11, 0.94). No significant difference was found in the incidence of extra-pseudocapsule cancer lesions between the tumors 2.5 cm or less and that greater than 2.5 cm.
These data suggest that when partial nephrectomy is performed in RCC 4 cm or less, a 10mm margin may be too large and go against renal function maintaining. Enucleation alone was associated with a significant risk of incomplete excision, and therefore liable for local recurrence. Thorough inspection of the whole kidney before and during operation may help to avoid leaving over large and distant multifocal lesions.
直径4cm及以下的肾细胞癌（RCC）多中心性和转移发生率较低，通常被认为适合保留肾单位手术（NSS）。本研究旨在探讨假性包膜外癌灶与原发肿瘤之间的距离，并提出直径4cm及以下RCC行NSS时正常肾实质的最佳切缘。
我们前瞻性研究了82例接受根治性肾切除术切除直径4cm及以下RCC的肾脏。根据UICC TNM分类（1997年），所有肿瘤均为T1期，76例为传统型RCC，6例为乳头状RCC。肾脏样本首先以3mm间隔进行连续切片以检查多中心性。然后，在每一层切片组织上，对假性包膜外15mm的肾实质切缘进行连续切片并显微镜检查，以研究假性包膜的完整性以及假性包膜外癌灶的可能存在情况。测量假性包膜外病灶与原发肿瘤之间的最大距离。
82个原发肿瘤的直径为3.4±0.7mm（范围1.5 - 4.0cm）。其中，31.7%（26/82）未发现完整的假性包膜。82例中，19.5%（16/82）有假性包膜外阳性癌灶，其中侵犯正常肾实质的占12.2%（10/82），侵犯小静脉的占2.4%（2/82），卫星灶占4.9%（4/82）。假性包膜外癌灶与原发肿瘤之间的平均距离为0.5±1.3mm（范围0 - 5.0mm），95%置信区间（CI）为（0.11，0.94）。直径2.5cm及以下肿瘤与大于2.5cm肿瘤的假性包膜外癌灶发生率无显著差异。
这些数据表明，对直径4cm及以下的RCC行部分肾切除术时，10mm切缘可能过大，不利于肾功能的维持。单纯剜除术存在切除不完整的显著风险，因此易导致局部复发。手术前后对整个肾脏进行彻底检查可能有助于避免遗留过大和远处的多灶性病变。
