Nanocoll

SNd was accomplished by transurethral injection of 1 ml of intended technetium 80 MBq (Nanocoll^®, GE Healthcare, Milan, Italy), divided and deposited at four positions near the primary bladder tumor or around the resection scar if no residual tumor. Care was taken to solely inject into the detrusor muscle without perforation. The procedure was followed by direct RC. After removal of main specimen, SNd and nodal dissection were performed. The intended areas of nodal dissection were the obturator fossae bilaterally and along the iliac arteries up to iliac bifurcations. The SNd was completed by measuring radioactivity with a handheld Geiger meter over specifically dissected nodes. Counts per minute (CPM) were recorded for both SNs and non-SNs. Harvested lymph nodes were divided; one half for routine pathology and one for immunological analysis. Charts and anatomical maps were drawn, showing node-specific CPM, anatomical positions of obtained nodes and extracted tissues possibly harboring lymph nodes.

SLN scintigraphy was carried out according to the practical guidelines for lymphoscintigraphy and SLNB in melanoma of the European Association of Nuclear Medicine [13 (link)] and the german S3-guidline of melanoma treatment [14 ]. Hereby, a SLNB was recommended if tumor thickness was larger than 1 mm or additional risk factors like ulceration or an increased rate of mitosis were present. The implementation of SLNB was achieved by a defined protocol. The day prior to surgery, four intradermal peritumoral injections with 20 MBq ^99mTc-labeled human serum albumin colloid (Nanocoll®, GE Healthcare, Chicago, IL, USA) were applied. After imaging, SLNB was carried out using a portable gamma probe. Consecutively, all dissected lymph nodes were analyzed histopathologically. A false negative SLNB was assigned, if regional recurrence was detected in the exact lymphatic drainage of the previously performed SLNB.

Lymphoscintigraphy was performed on the day before surgery. Patients received Technetium-99m-labelled colloidal albumin (Nanocoll, GE Healthcare, Amersham, UK) 80 MBq in 0.2 ml injection intradermally into the primary tumour site on both sides of the excision scar and then proceeded to lymphoscintigraphy with static images at 30 min and 2 h from injection. The surgeon used a gamma-detecting probe intraoperatively for SLN detection and harvested all radioactive nodes until no focal residual activity remained. The surgeon decided individually the technique used to harvest pelvic lymph nodes, guided by lymphoscintigraphy and gamma probe. In most cases, a separate incision on the abdominal wall was made to retrieve deep pelvic lymph nodes. The radioactivity count of each sentinel node was recorded.

Technetium-99m-labeled albumin Nanocolloid (from January 2016 to February 2019: Nanocoll, GE Healthcare, Eindhoven, The Netherlands; from March 2019 to April 2021: Nanoscan, Radiopharmacy, Budaörs, Hungary) was administrated via an intratumoral injection, by a resident or an experienced nuclear medicine physician, either by palpation in palpable tumors or ultrasound-guided in nonpalpable tumors. An injected dose of approximately 120-MBq technetium-99m-labeled albumin Nanocolloid in a volume of 0.25 ml was administered in the afternoon of the day prior to surgery. Planar lymphoscintigraphy was performed at 15-min pi and 2-h pi. If planar lymphoscintigraphy showed SLN nonvisualization at 2-h pi, single photon emission computed tomography/computed tomography (SPECT/CT) imaging or a second periareolar injection of 120 MBq, followed by repeated planar lymphoscintigraphy, and sometimes additional SPECT/CT imaging, 2-h later (i.e. 4-h pi), were performed. As nonvisualization at 2-h pi is an important decision moment for further diagnostic intervention, we focused our analysis on this time point. Focal accumulations in at least one axillar lymph node were defined as SLN. SLN nonvisualization was clinically classified as nonvisualization when no SLN was visualized on routine clinical lymphoscintigraphy, as earlier described [8 (link)].