Background: Lymphatic mapping in patients with breast cancer can reveal sen
tinel lymph nodes that are not located at level I-II of the axilla. Little
is known about the clinical relevance of these nodes.
Methods: Some 113 consecutive patients with clinical stage T1-3N0M0 breast
cancer were studied. Based on preoperative lymphoscintigraphy, sentinel nod
e biopsy was performed guided by a gamma probe and patent blue dye. All sen
tinel nodes that were visible on lymphoscintigraphy were sought. Pathologic
al examination of the sentinel nodes included step-sections and staining wi
th CAM 5.2. Axillary node dissection was performed regardless of sentinel l
ymph node status.
Results: Twenty-one (19 per cent) of 113 patients had sentinel lymph nodes
outside level I-II of the axilla, mostly in the internal mammary chain. Twe
nty-two of the 30 sentinel nodes at these sites were harvested. Three patie
nts had sentinel nodes only outside the axilla. Four other patients had met
astases outside the axilla. This changed postoperative treatment in three p
atients. No postoperative complication occurred.
Conclusion: Sentinel lymph nodes outside level I-II of the axilla were pres
ent in 19 per cent of patients with breast cancer in this series. Biopsy of
these nodes was technically demanding but was performed without additional
morbidity. The clinical impact was limited; treatment changed in only 3 pe
r cent.