The purpose of this study was to compare diagnostic capacity of videothoracoscopic parasternal lemphadenectomy and open lymph node biopsy in detection of parasternal lymph node involvement and frequency of complications after use of these approaches. The study was performed on a population of 884 women with stage I-IIB breast cancer receiving conservation treatment at the Radiosurgery Department, N. N. Blokhin RCRC, RAMS, during 1990 through 2005. Open biopsy of parasternal lymph nodes on the affected side was made in 125 and videothoracoscopic parasternal lymphadenectomy was made in 759 of the 884 patients. By logistic regression analysis, videothoracoscopic parasternal lymphadenectomy provides a 2.5-fold higher chance to detect parasternal lymph node metastases as compared to open biopsy (p = 0.018). Complications were reported in 1.6% of cases following open biopsy versus 1.2% after videothoracoscopic parasternal lymphadenectomy (p = 0.1). As compared to biopsy, videothoracoscopic parasternal lymphadenectomy is a surgical intervention of choice ensuring more objective information on the status of the lymph nodes in question and associated with a lower frequency of complications.