Comparison of combined and intradermal radiocolloid injection techniques to performe sentinel lymph node biopsy at early stage breast cancer

Breast cancer is the second most common cancer in women. It accounts for 33 percent of all female cancers and is responsible for 20 percent of the cancer-related deaths in women. The axillary nodal status is the most powerful prognostic factor for early breast cancer. Axillary lymph node dissections have traditionally been used to establish the malignant status of the lymph nodes. Sentinel node biopsy has rapidly emerged as a minimally invasive, highly accurate method of axillary staging, and has replaced routine axillary lymph node dissection as the new standard of care in breast cancer.The aim of our study was to compare the efficacy of combined (pericaviter+intradermal and peritumoral+intradermal) and intradermal radiocolloid injection in sentinel lymph node mapping for early stage breast cancer. Totally, two hundred and thirty-seven patients with histopatologically confirmed breast cancer underwent SLN mapping using radiocolloid and blue dye followed by a axillary dissection. The first 41 patients had combined injection of radioicolloid given in four sides around the tumor and one injection into dermis over the tumour. The remaining 196 patients had an intradermal injection given in four sides over the tumour. 110 patients in both groups had blue dye injected around the tumour or periareolar or subdermal. Sentinel nodes were identified using a lymphoscintigraphy, blue dye and an gamma probe. Overall the SLN detection rate for preoperative lymphoscintigraphy, gamma probe and blue dye procedure were %96.2, %94.2 and %76.4 respectively. The SLN detection rate of combined and intradermal radiokolloid injection by preoperative lymphoscintigraphy and gamma probe were %90.2, %96.2 and %85.4, %94.9 respectively. The preoperative lymphoscintigraphy and hand held gamma probe demonstrated a SLN significantly more often in the intradermal injection than combined injection (p value respectivly 0.051 and 0.002). False negative rate was % 16.6 in the combined injection and %9.2 in the intradermal injection.Our results show that intradermal injection of radiocolloid is more successfull at the SLN dedection compared with combined injection. The false-negative rate is also minimized by the use of intradermal injection.