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Lymphoscintigraphy is a nuclear medicine imaging technique for mapping the lymphatic system using radiopharmaceuticals or radiotracers. Lymphoscintigraphy is a critical evaluation tool for patients with various malignancies, including breast cancer and melanoma. Identifying sentinel lymph nodes via lymphoscintigraphy facilitates treatment planning and helps patients avoid unnecessary invasive procedures such as lymphadenectomy. Lymphoscintigraphy is a vital evaluation tool for patients with lymphedema unrelated to malignant disease. Lymphoscintigraphy is noninvasive, apart from targeted radiotracer injections, and has a low complication rate while having few contraindications. Applications for lymphoscintigraphy continue to expand as clinicians seek to minimize invasive, sometimes disfiguring, therapies for malignancy. This activity reviews the pertinent anatomy, indications, contraindications, complications, necessary equipment, procedural steps, and clinical application of lymphoscintigraphy and highlights the critical role of the interprofessional team in improving outcomes for patients undergoing this imaging study. Objectives: Identify appropriate candidates for lymphoscintigraphy based on their clinical history. Apply knowledge of lymphatic anatomy and physiology to interpret lymphoscintigraphy findings in the context of specific disease processes. Screen patients for contraindications to lymphoscintigraphy to mitigate potentially adverse outcomes. Develop and implement effective interprofessional team strategies to improve outcomes for patients undergoing lymphoscintography. Access free multiple choice questions on this topic.

Lymphoscintigraphy is a nuclear medicine imaging study for mapping the lymphatic system with scintigraphy. Attempts at understanding and mapping the lymphatic system began in the 1600s with the discovery of the cisterna chyli and thoracic duct.[1] The lymphatic drainage of the breast was first described in 1786 and identified 2 dominant drainage pathways of the breast: the axillary lymphatic basin and the internal mammary nodes.[2] Subsequently, intradermal or parenchymal injection of scintigraphic agents was found to be equivalent to an intralymphatic injection. In the late 20th century, protocols employing radiopaque contrast agents to visualize the first lymph node to receive the contrast agent, also termed the “sentinel lymph node,” were developed.[3] Several radioisotopes have been used for lymphoscintigraphy; current lymphoscintigraphic techniques utilize Technetium Tc 99m sulfur colloid.[4] The ideal radiotracer for lymphoscintigraphy will demonstrate rapid transfer to and prolonged stay within the lymph node. Understanding the map of lymphatic drainage patterns of anatomical structures defines the clinical application of lymphoscintigraphy. A sentinel lymph node is the first node that accepts lymphatic drainage from an anatomical site. In cases of malignancy, such as malignant melanoma or breast cancer, the sentinel lymph node is most likely to harbor occult metastases. Sentinel lymph node histopathologic analysis, in the absence of overt metastases, can potentially preclude the need for adjuvant therapies, including lymphadenectomy, radiotherapy, chemotherapy, or more invasive surgical procedures. Lymphoscintigraphy has become the standard of care when managing select breast cancer and melanoma cases; other applications include the evaluation of lymphedema.[4]

Lymphoscintigraphy is relatively noninvasive and has few adverse effects. One of the most common complications associated with lymphoscintigraphy is radiopharmaceutical extravasation into perivascular tissues; no long-term adverse effects have been reported. Another common complication of lymphoscintigraphy is an allergic reaction to the radiotracer or its preparation. Allergic reactions to radiotracers are rare; reactions to the preparation contents, such as lidocaine, are more common.

Lymphoscintigraphy is a diagnostic nuclear medicine imaging modality that employs radiotracers to identify neoplastic lymph node involvement and lymphatic system flow issues. The most effective way to enhance patient outcomes is through coordination of care to smoothly execute the examination, interpret the results, and relay those results to the pertinent parties. This coordination of care begins before the patient arrives at the imaging facility. Accurate and timely scheduling of the examination facilitates patient satisfaction. Once the study is scheduled, the ordering physician should be informed; some patients must proceed immediately to sentinel lymph node biopsy. A comprehensive preimaging questionnaire should be completed with the assistance of clinical nursing or scheduling staff. This questionnaire should include inquiries about recent surgical procedures, imaging studies with radiopharmaceuticals, and a general medical history. Particular attention must be paid to any history of allergic reactions, particularly to radiopharmaceuticals; while rare, such an allergy may require modifications to the radiotracer preparation or alternate imaging methods. The nuclear medicine technician must perform scintillation camera quality control measures according to the general guidelines of the Society of Nuclear Medicine. The chosen radiotracers should be prepared and shipped when necessary within an appropriate timeframe to avoid radioactive decay.