Sole brachytherapy for partial breast irradiation is a new approach in the adjuvant treatment of early stage breast carcinoma. The method is suitable for patients with low risk of local recurrence - tumor less than 3 cm, NO, oř maximal 3 nodes positive, invasive ductal histology with negative margins, age over 40 years, steroid receptors positive, low grade tumors. The aim of the clinical study performed in the Masaryk Memoriál Cancer Institute was to establish the method of peroperative interstitial HDR brachytherapy and evaluate the local control, complications and cosmesis of this method. Methods: Between March 2002 and July 2004,25 women with stage I-II breast cancer without risk factors for the local relapse were enrolled into the study. All patients underwent partial mastectomy with dissection of the axilla oř sentinel node biopsy. Brachytherapy catheters were placed into the area of tumour bed at the time of excision. Conformal planning was performed in the BrachyVision planning systém using the three-dimensional reconstruction of CT scans. Irradiation was started 5 days after surgery when the finál histology was received. High dose rate (HDR) afterloader Varisource with 192Ir source was ušed to deliver 3,4 or 4,0 Gy per fraction, 8-10 fractions in 4-5 consecutive days to the target volume. Results: 19 patiens were eligible for this study. The medián patient age was 63 years. The medián follow-up was 11 months. One local recurrence was diagnosed 19 months after brachytherapy. It occurred in another quadrant and was histologically distinct from the originál tumor. The globál cosmetic scores were good to excelent in 18 cases and fair in I patient. Conclusion: The preliminary results of our study are encouraging for the use of sole peroperative interstitial brachytherapy in selected patients with early stage breast cancer

        Key words: breast cancer, radiotherapy, peroperative radiotherapy, interstitial HDR brachyterapy