Lymphatic mapping and sentinel lymph node biopsy in breast cancer

Abstract

Lymphatic mapping with selective lymphadenectomy is an attractive approach in breast-cancer patients. It uses existing technology to exploit logical anatomic and physiological principles to identify occult regional lymph-node metastases. The lymphatic flow is visualized and the first (sentinel) lymph node on a direct drainage pathway from the primary tumour is identified. This is the node at greatest risk of harbouring metastatic deposits. Retrieving this node requires a concerted effort from the nuclear medicine physician, surgeon and pathologist. Lymphoscintigraphy can indicate the number of sentinel nodes and their location. The surgeon can use two techniques to find the node. A vital dye injected at the tumour site will stain the lymphatic duct as well as the sentinel node and allow their visual identification. Alternatively, a lymph-node-seeking radiopharmaceutical will also migrate from the tumour site to the sentinel node and will enable its retrieval with the use of a gamma detection probe. The pathologist has a number of techniques to identify tumour deposits in the lymph node. A review of the literature shows that the sentinel node can be found in more than 90% of the patients. With experience, the false-negative rate can be kept down to about 5%. This novel approach of lymphatic mapping with selective lymphadenectomy may lead to a substantial reduction in the need for axillary node dissection in patients with breast cancer without compromising survival and regional control, and without loss of prognostic and staging information. This development will translate into a great reduction in patient morbidity and medical expenses.

Detection of sentinel lymph nodes by SPECT/CT and planar scintigraphy: The influence of age, gender and BMI

“…SLN has been incorporated in the routine management of various solid tumor types [24][25][26] . SLN biopsy has an established role in malignant melanoma and breast cancer [26,27] .…”

Polymeric micelles and molecular modeling applied to the development of radiopharmaceuticals

“…Radiopharmaceutical colloidal preparations should have particulates with uniform size below 100 nm, which are able to travel from the injection site and reach the lymphatic ducts and lymph nodes. Very large particles fail to migrate and tend to remain in the interstitium at the injection site whereas particles smaller than 4-5 nm travel so quickly that only a fraction is retained in the first (sentinel) lymph node (Nieweg et al, 1999;Henze et al, 1982;Ege, 1976). In addition, excessively small particles will likely cross the endothelium and promptly enter into blood circulation (Nieweg et al, 1999).…”

“…The SLN in particular, is the first lymph node subject to direct drainage from the primary lesion site of the tumor, being more likely to contain metastatic tumor cells than other lymph nodes in the same region. Usually, the prognostic significantly improves when cancer cells are not found in the SLN by pathological examination (Kowalsky, Falen, 2004;Goins, Phillips, 2001 Tc-human serum albumin, are currently used for detecting SLNs (Sener et al, 2004;Vera, Wallace, Hoh, 2001;Nieweg et al, 1999). The colloidal forms, especially 99m Tc filtered sulfur colloid, have slower rate of clearance from the site of injection.…”

Surgical Management of Breast Cancer in the Future

“…Numerous reports are now emerging indicating that this assumption is valid, and a review of the literature shows that the sentinel node can be found in more than 90% of patients, and the false-negative rate can be held down by about 5%. (21). There are still unsolved questions on some technical details, but the method per se seems to have been accepted.…”