Gommans G M, van Dongen A, van der Schors T G, Gommans E, Visser J F, Clarijs W W, de Waard J W, van de Bos J, Boer R O
Department of Nuclear Medicine, Westfries Gasthuis Hoorn, WFG Hospital Hoorn, The Netherlands.
Eur J Nucl Med. 2001 Oct;28(10):1450-5. doi: 10.1007/s002590100590.
The sentinel node (SLN) procedure has gained widespread acceptance for the axillary staging of patients who present with carcinoma of the breast. A first series of 21 patients were imaged 2 and 4 h after the injection of technetium-99m colloidal albumin. Preoperatively, axillary foci were located scintigraphically and with a hand-held gamma probe that was also used to detect the radiolabelled nodes 22 h later in the operating theatre. In a high percentage of our first series it was difficult to localise the sentinel node owing to a low count rate ex vivo. The aim of this study was to facilitate the detection of sentinel nodes by improving the count rate by the use of higher specific concentrations of 99mTc-colloidal albumin, with increased radiochemical labelling efficiency and stability. In vitro tests were performed to establish the radiochemical labelling efficiency and stability of different concentrations of 99-mTc-colloidal albumin. Concentrations of 2.5, 10, 20, 25, 30, 37 and 50 MBq 99mTc/microg colloidal albumin (Nanocoll) were prepared under nitrogen and in vacuum. The quality of the solutions was assessed by testing the radiochemical labelling efficiency and stability after 0.5, 2, 5, 8 and 24 h. The particle size of colloidal albumin was tested by dynamic light scattering at 30.2 degrees, 62.6 degrees and 90.0 degrees angles. Following the results of the in vitro studies, higher concentrations of 99mTc-colloidal albumin were used in vivo in a further series of 98 patients. For labelling under nitrogen, a maximum acceptable concentration of 10 MBq/microg was found, which complies with the specifications of the manufacturer. By preparing the labelling in vacuum vials, a 2.5 times greater radiochemical labelling efficiency over the entire period was achieved, and a significant improvement (P<0.002) in the in vivo series was found. It is concluded that although the rate of successful visualisation of the SLN was high in all studies, a better count rate (nine times higher) was achieved with the highest concentration of 99mTc-colloidal albumin, which facilitated the detection of the SLN by the gamma probe during surgery.
前哨淋巴结（SLN）活检术已被广泛应用于乳腺癌患者的腋窝分期。对首批21例患者在注射99m锝胶体白蛋白后2小时和4小时进行成像。术前，通过闪烁扫描法和手持式γ探针定位腋窝病灶，该探针在22小时后也用于在手术室中检测放射性标记的淋巴结。在我们的首批病例中，由于体外计数率较低，前哨淋巴结的定位在很大比例的病例中存在困难。本研究的目的是通过使用更高比浓度的99mTc-胶体白蛋白来提高计数率，从而促进前哨淋巴结的检测，同时提高放射化学标记效率和稳定性。进行体外试验以确定不同浓度的99mTc-胶体白蛋白的放射化学标记效率和稳定性。在氮气和真空条件下制备浓度为2.5、10、20、25、30、37和50 MBq 99mTc/μg胶体白蛋白（纳米胶体）的溶液。通过在0.5、2、5、8和24小时后测试放射化学标记效率和稳定性来评估溶液质量。通过动态光散射在30.2度、62.6度和90.0度角测试胶体白蛋白的粒径。根据体外研究结果，在另外98例患者中体内使用了更高浓度的99mTc-胶体白蛋白。对于在氮气下标记，发现最大可接受浓度为10 MBq/μg，符合制造商的规格。通过在真空瓶中进行标记，在整个期间实现了2.5倍更高的放射化学标记效率，并且在体内系列中发现了显著改善（P<0.002）。结论是，尽管在所有研究中前哨淋巴结成功可视化的比率都很高，但使用最高浓度的99mTc-胶体白蛋白实现了更好的计数率（高9倍），这有助于在手术期间通过γ探针检测前哨淋巴结。
