False Negative Sentinel Lymph Node Biopsies in Melanoma May Result From Deficiencies in Nuclear Medicine, Surgery, or Pathology

Abstract

An FN SN can occur because of deficiencies in nuclear medicine, surgery, or pathology. qRT can detect "occult" metastatic melanoma in SNs that have been identified as negative by histopathology.

EANM practice guidelines for lymphoscintigraphy and sentinel lymph node biopsy in melanoma

“…Analysis of false-negative procedures has revealed that the cause may lie with each of its three elements [66,70,71]. Causative factors in lymphoscintigraphy may be imaging of the wrong nodal basin, or failure to depict all potential drainage basins, failure to visualize the afferent lymph vessel, or failure to detect an SLN in an unusual location.…”

False‐negative sentinel node biopsy in melanoma

“…The lack of a commonly accepted definition of a sentinel node implies that one man's sentinel node is not necessarily somebody else's [2]. Analysis of 33 patients with a false-negative sentinel node biopsy at the Melanoma Institute Australia showed that there were process deficiencies in nuclear medicine for 31% of these cases, in pathology for 31%, and in surgery for 13% [3]. The lymph flow may be diverted to another node-a ''neo''sentinel node-because the original sentinel node is largely replaced by metastatic disease or because the afferent lymph vessel is blocked by in-transit metastases.…”

“…False-negativity has also been found to be associated with increasing age, lower Breslow thickness, higher Breslow thickness, ulceration, and less lymphovascular invasion. A complete regression of a metastasis in the sentinel node but not in a subsequent node may also be a potential cause for failure [3].How does the false-negative rate for melanoma compare to that for other cancers? A recent study of 153 patients who underwent sentinel lymph node biopsy for Merkel cell carcinoma revealed a false-negative rate of 15% [5].…”

Uncertainties in the management of melanoma nodal metastasis

“…2 It has been shown up to 30% of the false negative cases of sentinel node biopsy could be avoided with a more comprehensive examination of the specimens. 3 Additionally, there remains some controversy regarding the prognostic value of sentinel node biopsy in thin (<1 mm) melanomas, in childhood melanoma, in melanocytic tumours of uncertain malignant potential as well as in patients with local recurrence or satellite/in transit metastasis and previous negative sentinel node biopsy. These are important areas for investigation.…”