ABSTRACT
A retrospective study was conducted from a review of the medical records of patients with early-stage, invasive breast cancer who underwent surgical treatment and sentinel node biopsy with a radiotracer from January 2008 to August 2012 at a single institution (221 patients included). The patients were grouped according to the time of (99m)Tc Dextran-500 injection, which was preoperatively (with lymphoscintigraphy) (81 patients) or intraoperatively (140 patients). The purpose of the report is to compare the results of sentinel node biopsy of early-stage breast cancer patients who were subjected to intraoperative (99m)Tc Dextran-500 injections with the patients who received preoperative injections. The following parameters were analyzed: clinical tumor staging, histological and pathological results, size and number of tumor foci, peritumoral vascular invasion, number of lymph nodes removed, size of lymph node metastasis and hormone receptor expression.There were no differences in sentinel lymph node localization whether (99m)Tc Dextran-500 was injected preoperatively or intraoperatively.
ABSTRACT
BACKGROUND: Breast cancer surgery has evolved towards minimizing morbidity, maximizing cure rates and stratifying treatments according to disease stage. Sentinel lymph node biopsy is becoming standard practice in most centres. However, no standard radiopharmaceutical exists. OBJECTIVES: To blindly compare 99mTc dextran 500 and 99mTc phytate in the scintigraphic detection of sentinel lymph nodes. Endpoints were the detection of axillary or internal mammary lymph nodes, number of lymph nodes detected, detectability in the first versus the second hour of evaluation and the relationship between rate of detection and age or body mass index. METHODS: Forty-six patients with histological diagnosis of early breast cancer, without previous surgical treatment, were enrolled in our study. Each patient underwent lymphoscintigraphy twice: on one day with 99mTc dextran 500 and on another day with 99mTc phytate. Images were acquired 1 h and 2 h after tracer administration. RESULTS: Eighty-eight lymphoscintigraphic studies were performed in 44 patients. On the first image (taken at 1 h), 34 patients from the 99mTc dextran group showed sentinel nodes compared with 28 positive examinations using 99mTc phytate (P = 0.113). On the second image (taken at 2 h) 39 patients from the 99mTc dextran group showed positive results compared to 30 positive examinations using 99mTc phytate (P = 0.036). There was no statistically significant correlation between the body mass index or age and the result of the lymphoscintigraphy. CONCLUSION: 99mTc dextran 500 is better than 99mTc phytate for use in a 2 h interval scintigraphic protocol because it demonstrates the sentinel node in a significantly higher number of patients and also showed more lymph nodes suitable for pathological examination.
