Sentinel node biopsy is not sensible in breast cancer patients with large primary tumours

Aims We aimed to evaluate the outcome of sentinel node biopsy (SNB) in breast cancer patients with large primary tumours. Methods Nine hundred and eighty-four patients with invasive breast cancer and SNB were studied. The histological tumour size was larger than 3 cm in 70 patients. The advantages of SNB like avoiding axillary clearance (AC) or more accurate staging by detecting micrometastases or parasternal sentinel node metastases were evaluated in relation to the tumour size. Results Axillary metastases were detected in 351/914 patients with a tumour size of 3 cm or smaller and in 50/70 patients with larger tumours (pmuch less-than0.0001). Micrometastases or isolated tumour cells only, were observed in 134/351 node positive patients with tumours not larger than 3 cm and in 10/50 cases with larger tumours (p=0.022). Parasternal sentinel node metastases were detected in 17/914 patients with a tumour size of 3 cm or smaller and 2/70 patients with larger tumours (p=ns). AC was omitted because of tumour negative sentinel node findings 168 of the 232 patients with stage T1 a–b tumours and 281 of those 489 with T1c tumours. Twenty of the 70 patients with tumours larger than 3 cm avoided AC. Conclusions SNB is not sensible in breast cancer patients with tumours larger than 3 cm, because of the small proportion avoiding AC after SNB.