Sentinel node localization in patients with non-palpable breast cancer

The aim of this study was to demonstrate that radionuclide sentinel node detection can be applied to patients with non-palpable breast cancer. One hundred and ten consecutive women with unilateral breast cancer were studied. Group 1 was made up of 80 patients with palpable breast cancer (mean age, 58 years) and group 2 of 30 patients with non-palpable breast cancer detected mammographically (mean age, 55 years). 99mTc-nanocolloid (111 MBq) was injected peritumorally in palpable tumours, and in the tumour area (ultrasound guided) in non-palpable tumours. At 2 h post-injection, anterior and lateral scintigrams were obtained from patients in the supine position. The location of the sentinel node was marked on the patient's skin. Patients with non-palpable tumours were moved to the surgery room 3 h later, and those with palpable tumours 24 h later. The histopathological study included three haematoxylineosin sections and immunochemistry. All patients underwent axillary lymphadenectomy. The sentinel node was detected in 67 cases (84) in group 1 and in 28 cases (93) in group 2. In four patients (5) in group 1 and two patients (7) in group 2, no axillary sentinel node was detected in the surgical bed, although it had been seen in scintigraphy. In nine patients (11) in group 1, neither scintigraphic nor surgical detection was successful. Skip metastasis was seen in six cases (10) of palpable tumours and in one case (4) of non-palpable tumours. It can be concluded that non-palpable breast tumours cannot be considered an exclusion criterion for sentinel node localization and biopsy. Ultrasonography-guided injection, followed by scintigraphic and surgical detection of the sentinel node, may help in the management of patients with non-palpable breast tumours.