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). Tc-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.