Objective: To find out if the sentinel node can be detected in sufficient n
umbers of women with breast cancer to be useful as a prognostic sign, wheth
er it reflects that state of the entire axilla, and whether it detects micr
ometastases that would otherwise be missed.
Design: Prospective study.
Setting: 3 teaching hospitals, Sweden.
Subjects: 75 patients with breast cancer who were Listed to have axillary d
issection as well as resection of their tumour.
Interventions: Injection of Tc-99 nanocolloid 0.4 mi and patent blue dye 1
mi around the tumour or under the skin above the tumour, followed by preope
rative lymphoscintigraphy and then identification of the sentinel node duri
ng operation either because it had turned blue or with a gamma probe. Remov
al of the sentinel node and complete axillary dissection.
Main outcome measures: Identification of the sentinel node and presence of
metastatic nodes in the axilla.
Results: The sentinel node was identified in 69/75 (92%). It correctly pred
icted the state of the axilla in 66/69 (96%), and detected metastases in 24
of the 27 with invaded nodes in the axilla (89%). The false negative rate
was 11%. In 14/27 with axillary metastases (52%) the sentinel node was the
only involved node. In 3/24, metastases were detected by immunohistochemist
ry alone.
Conclusion: Biopsy of the sentinel node predicted the presence or absence o
f axillary metastases with acceptable accuracy. However, before axillary no
de dissection is rejected in favour of sentinel node biopsy alone, large mu
lticentre studies are needed to establish the true false negative rate.