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Introduction: Sentinel lymph node (SLN) biopsy is the evolving standard of care for the management of early breast cancer. Accurate identification of the SLN is paramount for success of this procedure. Various techniques are described for SLN identification, but the superficial injection techniques, advocated by the UK National Training Programme (NEW START), are validated, reproducible and rapid. Pre-operative lymphoscintigraphy provides a road map for the surgeon and requires a reporting template., Methods: As one of the NEW START training institutions in the UK practising this technique, we reviewed a mature series of 100 unselected, consecutive SLN lymphoscintigraphy procedures. We correlated the imaging, operative and pathology findings and have provided technical details of the technique and a template for reporting SLN lymphoscintigrams., Results: The SLN localisation rate was 99% with one failed imaging. Seven patients required delayed imaging. The mean activity of the radiocolloid injected was 14.4MBq (range 8.3-23 MBq). The SLNs were visualised in the ipsilateral axilla in 98 images, intramammary in 3, and internal mammary in 1. A mean of 1.35 nodes were classified as 'True' SLNs on imaging criteria. Intra-operatively, a mean of 1.91 SLNs were excised. 32 of 116 hot and blue nodes, 7 of 15 only blue nodes, 13 of 47 only hot and 7 of 13 parasentinel nodes harboured metastases., Conclusion: The NEW START recommended, combined superficial injection techniques, have high localisation rates. Pre-operative sentinel node imaging is recommended and a template for reporting is provided.

Procedure guidelines for scintigraphic detection of sentinel node in breast cancer are presented.

Background: Sentinel node biopsy is becoming the staging investigation of choice for early breast cancer. Optimal identification of the sentinel node requires the utilization of a radionuclide in combination with blue dye. Gamma probe guided surgery is a skill that is currently unfamiliar to many surgeons. Appropriate training within the surgical skills laboratory could play a major role in the widespread implementation of this technique, but no suitable model currently exists for this purpose., Aim: To develop a realistic phantom for the teaching and practice of the core new skills required of a surgeon to perform gamma probe guided sentinel node biopsy in breast cancer., Methods: We describe the development of our sentinel node biopsy simulator which consists of a torso with its arm extended in an operating position. The replaceable breast and axilla are constructed from a thermoplastic elastomer gel, which has similar physical and radiation attenuation properties to that of human tissue. Radionuclide injection sites and radioactive sentinel nodes are simulated by hollow blue coloured PVC beads filled with Technetium-99m. The model allows demonstration and practice of injection techniques, imaging techniques and gamma probe guided removal of sentinel nodes., Conclusion: We believe that training for sentinel node biopsy should begin in the surgical skills laboratory. The model we have developed is able to provide an accurate simulation of all new practical skills required for accurate sentinel node identification. It is an important aid to training in the sentinel lymph node biopsy procedure for breast carcinoma.

The aim of this study was to evaluate the role of dynamic imaging in sentinel lymph node (SLN) biopsy in breast cancer. Patients with T1/T2, N0 invasive breast cancer underwent SLN localisation using intra-dermal injection of 15 MBq of 99mTc-nanocolloid. Gamma camera anterior-oblique dynamic imaging commenced simultaneously with tracer administration for 45 min, and was followed by anterior and lateral static imaging. Dynamic imaging data was reformatted into image files of different time-frames. Patterns of uptake were analysed using the sequences of dynamic frames and time-activity curve (TAC). SLN localisation was successful in 70/73 studies (96%) in 72 patients. Imaging information was present within the first 15 min of dynamic imaging in 67/70 studies (96%). Critical analysis of dynamic data helped to differentiate true SLN from secondary echelon nodes in eight studies and transient foci of radioactivity in six studies. In 17 studies, SLN contained metastatic disease. The detection of SLN metastasis was independent from the use of dynamic imaging. Dynamic imaging improves the interpretation of preoperative SLN imaging for breast cancer, but does not contribute significantly to the successful detection of SLN. Hence, preoperative dynamic imaging is not necessary in SLN biopsy for breast cancer.

Many publications attest to the potential of the sentinel lymph node technique in advancing the clinical management of melanoma and, more recently, breast cancer. Whilst not yet universally regarded as the standard of care, the technique is gaining wide acceptance. Use of a radiolabelled colloidal tracer is central to optimising sensitivity, and this brings with it the need to address radiation safety issues relating to the use of radioactive materials in the operating theatre and pathology laboratory, and the generation of radioactive waste. The radiation dose to the patient should also be determined if the professional is to reassure the patient by placing this in its proper context. For the purpose of this investigation, biodistribution data were obtained from patient studies to quantify the migration of tracer beyond the injection site, thereby permitting a detailed assessment of the internal dosimetry of the tracer and the resulting radiation dose to the patient. Uptake of tracer in the sentinel nodes, reticulo-endothelial system and circulating blood was investigated. The radiation dose to surgical staff was recorded using whole-body monitors and extremity dosimeters worn at the fingers. Clinical waste in the operating theatre was monitored and the radioactive content of significantly contaminated items determined. The radiation dose to pathology staff was estimated from knowledge of the radioactive content of the specimens obtained and a study of work practices. Migration of tracer was found to be minimal, with greater than 95% retention at the injection site. The effective dose resulting to the patient was 2.1x10(-2) mSv/MBq, with a mean breast dose of 7.2x10(-1) mGy/MBq. A mean whole-body dose of 0.34 microSv was received by surgical staff per procedure, with a mean finger dose of 0.09 mSv (90 microSv). Radiation doses received by pathology staff will be predominantly below measurable levels and are likely to be negligible unless primary specimens from a large number of studies are analysed promptly upon their excision. At operation, surgical swabs can become significantly contaminated and have been found to contain up to 22% of the administered activity, dependent upon the surgical procedure performed. It is concluded that moderate activities of technetium-99m labelled tracer are administered to the patient, and the radiation risk to the patient is consequently low relative to that from many other medical exposures. The radiation doses to staff groups involved in all aspects of the technique are low, and under normal circumstances and levels of workload, routine radiation monitoring will not be required. Standard biohazard precautions prevent direct intake of radioactive contamination. Radioactive waste is created in the operating theatre, and may be generated in the pathology laboratory if specimens are not routinely stored until fully decayed. This will require special handling if the disposal of radioactive material is not permitted.