Teaching points on lymphatic mapping for melanoma from the Sydney Melanoma Unit

If incorrect or misleading information is obtained from a sentinel node (SN) biopsy procedure for melanoma, inappropriate management decisions may be made, and the patient's outcome compromised as a result. As well, misleading prognostic indications may be provided to the patient. It is therefore important to correctly identify all SNs in every patient and to remove them all for examination. To reduce the likelihood of error, a high-quality preoperative lymphoscintigraphy (LSG) is the first prerequisite. The surgical procedure must then be undertaken with great care to remove all of the SNs that have been identified by the LSG. This will involve both blue dye mapping and use of a gamma probe. A thorough knowledge and understanding of common and uncommon sites at which SNs can be located, as outlined here, will not only make the surgery simpler and quicker, but will reduce the possibility of error by diminishing the risk of overlooking possible locations at which SNs may be found.