LOW-DOSE-RATE BRACHYTHERAPY AS THE SOLE RADIATION MODALITY IN THE MANAGEMENT OF PATIENTS WITH EARLY-STAGE BREAST-CANCER TREATED WITH BREAST-CONSERVING THERAPY - PRELIMINARY-RESULTS OF A PILOT TRIAL

Purpose: We present the preliminary findings of our in-house protocol treating the tumor bed alone after lumpectomy with low-dose-rate (LDR) interstitial brachytherapy in selected patients with early-stage brea st cancer treated with breast-conserving therapy (BCT). Methods and Ma terials: Since March 1, 1993, 60 women with early-stage breast cancer were entered into a protocol of tumor bed irradiation only using an in terstitial LDR implant with iodine-125. Patients were eligible if the tumor was less than or equal to 3 cm, margins were greater than or equ al to 2 mm, there was no extensive intraductal component, the axilla w as surgically staged, and a postoperative mammogram was performed. Imp lants were placed using a standardized template either at the time of reexcision or shortly after lumpectomy. A total of 50 Gy was delivered at 0.52 Gy/h over a period of 96 h to the lumpectomy bed plus a 2-cm margin. Perioperative complications, cosmetic outcome, and local contr ol were assessed. Results: The median follow-up for all patients is 20 months. Three patients experienced minimal perioperative pain that re quired temporary nonnarcotic analgesics. There have been four postoper ative infections which resolved with oral antibiotics. No significant skin reactions related to the implant were noted and no patient experi enced impaired would healing. Early cosmetic results reveal minimal ch anges consisting of transient hyperpigmentation of the skin at the pun cture sites and temporary induration in the tumor bed. Good to excelle nt cosmetic results were noted in all 19 patients followed up a minimu m of 24 months posttherapy. To date, 51 women have obtained 6-12-month follow-up mammograms and no recurrences have been noted. All patients currently have no physical signs of recurrence, and no patient has fa iled regionally or distantly. Conclusion: Treatment of the tumor bed a lone with LDR interstitial brachytherapy appears to be well tolerated, and early results are promising. Long-term follow-up of these patient s is necessary to establish the equivalence of this treatment approach compared to standard BCT, however. (C) 1997 Elsevier Science Inc.