Irradiation of the tumor bed alone after lumpectomy in selected patients with early-stage breast cancer treated with breast conserving therapy.
OBJECTIVE
We present the interim 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 breast cancer treated with breast conserving therapy (BCT).


METHODS
From 1 March 1993 through 1 January 1995, 50 women with early-stage breast cancer were entered into a protocol of tumor bed irradiation alone using an interstitial LDR implant. Patients were eligible if their tumor was an infiltrating ductal carcinoma < or =3 cm in diameter, surgical margins were clear by at least 2 mm, the tumor did not contain an extensive intraductal component, the axilla was surgically staged with < or =3 nodes involved with cancer, and a postoperative mammogram was performed. Implants were positioned using a template guide delivering 50 Gy over 96 hr to the lumpectomy bed plus a 1-2-cm margin. Local control, cosmetic outcome, and complications were assessed.


RESULTS
Patients ranged in age from 40 to 84 years (median, 65). The median tumor size was 10 mm (range, 1-25). Seventeen of 50 patients (34%) had well-differentiated tumors, 22 (44%) had moderately differentiated tumors, and in 11 (22%) the tumor was poorly differentiated. Forty-five patients (90%) were node-negative while five (10%) had 1-3 positive nodes. A total of 23 (46%) patients were placed on tamoxifen and 3 (6%) received adjuvant systemic chemotherapy. No patient was lost to follow-up. The median follow-up for surviving patients is 47 months (range, 37-59). No patient has experienced a local, regional, or distant failure. Three patients have died at 19, 33, and 39 months after treatment. All were without clinical evidence of recurrent disease and all deaths were unrelated to treatment. Good-to-excellent cosmetic results have been observed in 49 of 50 patients (98%) (median cosmetic follow-up was 44 months with a range of 19-59). No patient has experienced significant sequelae related to their implant.


CONCLUSIONS
Interim results with treatment of the tumor bed alone with an LDR interstitial implant appear promising. Long-term follow-up of these patients and additional studies will be necessary to establish the equivalence of this treatment approach compared to standard BCT.
Vicini
F
F
Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan 48073, USA. fvicini@beaumont.edu
Kini
V R
VR
Chen
P
P
Horwitz
E
E
Gustafson
G
G
Benitez
P
P
Edmundson
G
G
Goldstein
N
N
McCarthy
K
K
Martinez
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy; D001943:Breast Neoplasms / Q000532:radiotherapy* / Q000601:surgery*; D018270:Carcinoma, Ductal, Breast / Q000532:radiotherapy* / Q000601:surgery*; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D010865:Pilot Projects; D011879:Radiotherapy Dosage; D016019:Survival Analysis