The effect of patient and tumour characteristics on visualization of sentinel nodes after a single intratumoural injection of Tc 99m labelled human albumin colloid in breast cancer

Aims: The aim of the study was to study the influence of patient- or tumour-related factors on the lymphatic drainage patterns in breast cancer. Methods: The study included 290 consecutive breast cancer patients with lymphatic mapping and sentinel node biopsy. Lymphoscintigraphy was performed a median of four hours after a single intratumoral injection of 99mTc labelled human albumin colloid with two different particle sizes. Results: Lymphoscintigraphy showed axillary sentinel nodes in 253 (87%) and parasternal sentinel nodes in 49 (17%) patients. The median number of nodes seen in the axilla was one (range 0–5). No sentinel nodes were visualized in 27 (9%) patients. The number of the visualized axillary nodes was influenced by the particle size of the radiocolloid, and by metastatic involvement of the axillary nodes and the age and body mass index (BMI) of the patient. Patients with parasternal sentinel nodes were younger, had a lower BMI and had more often a non-palpable tumour. Conclusions:The age and BMI of the patient and the palpability of the tumour influence lymphatic drainage patterns in breast cancer. The metastatic involvement of axillary nodes seems to modify lymphatic drainage to the axilla.