To evaluate roles of preoperative lymphoscintigraphy for sentinel lymph node biopsy in breast cancer patients.

Five hundred and sixty-five consecutive breast cancer patients were prospectively randomized into groups with or without preoperative lymphoscintigraphy.

In a group with lymphoscintigraphy, 238 patients had sentinel lymph nodes spotted in lymphoscintigram. The visualization of sentinel lymph nodes in lymphoscintigram was not associated with patients' age, primary tumor size and location, histopathologic type and time interval from injection of radiocolloid to lymphoscintigraphy. However, patients with axillary metastasis had a lower identification rate of sentinel lymph nodes by lymphoscintigraphy than those without metastasis (P = 0.003). The identification rate of axillary sentinel lymph nodes was 99.3% in the group and the rate was similar whether there was sentinel lymph nodes spotted in axillary in lymphoscintigram or not (99.6% vs. 98.1%, P = 0.327). The false-negative rate in this group was 4.2%. While in a group without lymphoscintigraphy, the identification rate and the false-negative rate were 99.6% and 4.8%, respectively. There was no significant difference between the two groups in the identification rate of axillary sentinel lymph nodes (P = 0.594) and in the false-negative rate (P = 1.00).

Preoperative lymphoscintigraphy could neither improve the identification rate nor reduce the false-negative rate of breast cancer sentinel lymph node biopsy, and it is not necessary for sentinel lymph node biopsy in breast cancer patients.