32/Brachytherapy HDR in interoperative breast cancer treatment

Abstract

To present data from Linz, Austria, on survival and local control of a prospective treatment method and to demonstrate the safe use of combined external beam and interstitiallridium-192 HDR irradiation. This method has been transferred to Gynecological Clinic in Poznan, Poland, where the first implantation was performed in January 2004. a) Linz: Since 1984 HDR Ir-192 brachytherapy has been used to deliver an interstitial boost to the primary site in conservative breast cancer treatment. Until December 1995, 650 patients have been treated (T1: 434, T2: 216, N0: 467, N1: 183). Treatment method (after tumourectomy or quadrantectomy) included external beam irradiation of 45 to 50 Gy to the breast followed by an interstitial 10 Gy boost. Mean follow up of survivors: 105 months (range 36 to 189). b) Poznan: Ina 54 years old patient with breast cancer carcinoma ductale infiltrans G.2 pT2 tumourectomy was performed. In the same surgical session hollow needles where implanted into the tumour bed. Using an Iridium-192 source interstitial radiotherapy was delivered with a dose of 10 Gy as boost to the primary site. 5-years actuarial data for T1-2 tumours: Overall survival: 89.2%, local control: 96.9%, disease free survival: 86.4%, and disease specific survival: 92.8%. There were no severe complications, the cosmetic results are satisfactory (91% good to excellent after 5 years). The use of a HDR source in boosting the primary tumour site with a dose of 10 Gy in 1 fraction after external beam radiotherapy is a safe procedure; the impact on cosmetic results is minimal. Our 5-year local relapse rate of 3.1%and survival data are satisfactory and better compared to most of the results reported in literature. Therefore we will continue with the described prospective approach in Linz. The first implantation in Poznan was the kick off for further brachytherapy treatments in breast cancer patients. High dose rate implantantions in the treatment of breast cancer will continue at the Gynecological Clinic in Poznan, either as a boost or as the sole treatment of mammary glant carcinoma.