Lowen, Mary Ann

Abstract Background: The ECOG E5194 study was a prospective trial designed to evaluate surgical excision (lumpectomy) without radiation for selected women with ductal carcinoma in situ (DCIS) of the breast with low risk clinical and pathologic features. Methods: Eligible patients were enrolled on two study cohorts (not randomized): (1) low or intermediate grade DCIS, tumor size < 2.5 cm; or (2) high grade DCIS, tumor size < 1.0 cm. Cohort assignment was based on pathology assessment from the treating institution. Protocol specifications included surgical excision of the DCIS tumor with a minimum negative margin width of at least 3 mm or no tumor on re-excision. Radiation treatment was not allowed. From April 1997 to October 2002, 665 evaluable patients were enrolled through ECOG or NCCTG (561 in Cohort 1; 104 in Cohort 2). Tamoxifen was optional (not randomized) beginning in May 2000, and was given to 30% of the patients. The primary study endpoint was the rate of developing an ipsilateral breast event (IBE), defined as local recurrence of DCIS or invasive carcinoma in the treated breast. The median follow-up was 12.3 years. We have previously reported 7-year results (L. Hughes, J Clin Oncol 27:5319, 2009; median follow-up 6.3 years; 66 IBE’s), and we herein provide 12-year results. Results: Median patient age was 60 years and 58 years for Cohort 1 and Cohort 2, respectively. Tumor size was < 10 mm for 79% and 80% of patients, respectively. The minimum negative margin width was > 5 mm for 64% and 69% of patients, respectively. There were 99 IBE’s, of which 51 (52%) were an invasive IBE. The IBE and invasive IBE rates increased over time in both cohorts (see Table). The 12-year rates of an IBE were 14.4% for Cohort 1 and 24.6% for Cohort 2 (p = 0.003), and for an invasive IBE, 7.5% and 13.4%, respectively (p = 0.08). No difference was seen for the 12-year rates of overall survival (84.0% vs 82.8%; p = .96) or contralateral breast events (6.7% vs 12.0%; p = 0.16). On multivariate analysis, study cohort (hazard ratio = 1.81; p = 0.01) and tumor size (p = 0.01) were statistically significant for an IBE, and study cohort was borderline statistically significant for an invasive IBE (p = 0.08). On central pathology review (75% of cases), neither grade nor comedo necrosis was associated with the risk of an IBE or invasive IBE (all p > 0.15). Salvage treatment at the time of an IBE included mastectomy for 42% (31/74) and 64% (16/25) of the patients, respectively. Conclusions: For these selected patients with favorable DCIS based on clinical and pathologic characteristics treated with surgical excision without radiation, the rates of an IBE and an invasive IBE continued to increase through at least 12 years of follow-up. IBE Rates According To Study Cohort. Cohort 1 (Low or Intermediate Grade)Cohort 2 (High Grade)TimeIBEInvasive IBEIBEInvasive IBEAt 5 years6.0% (4.0%, 8.1%)2.7% (1.3%, 4.1%)15.0% (7.7%, 21.7%)5.3% (0.8%, 9.7%)At 7 years9.5% (7.0%, 12.0%)4.8% (2.9%, 6.6%)18.2% (10.6%, 25.8%)7.6% (2.2%, 13.0%)At 10 years12.5% (9.5%, 15.4%)6.4% (4.2%, 8.6%)24.6% (15.7%, 33.4%)13.4% (5.9%, 20.9%)At 12 years14.4% (11.2%, 17.6%)7.5% (5.1%, 10.0%)24.6% (15.7%, 33.4%)13.4% (5.9%, 20.9%) Citation Format: Lawrence J Solin, Robert Gray, Lorie L Hughes, William C Wood, Mary Ann Lowen, Sunil Badve, Frederick L Baehner, James N Ingle, Edith A Perez, Abram Recht, Joseph Sparano, Kathy Miller, Nancy E Davidson. Local excision without radiation for ductal carcinoma in situ: 12-year results from the ECOG E5194 study [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-13-01.

PurposeTo determine the risk of ipsilateral breast events in patients with ductal carcinoma in situ (DCIS) treated with local excision without irradiation.Patients and MethodsPatients with either low- or intermediate-grade DCIS measuring 2.5 cm or smaller, or high-grade DCIS measuring 1 cm or smaller who had microscopic margin widths of 3 mm or wider and no residual calcifications on postoperative mammograms were eligible for a prospective trial conducted from 1997 to 2002 by the Eastern Cooperative Oncology Group and North Central Cancer Treatment Group. Patients entered in 2000 and later could take tamoxifen if they wished. Median age at last surgery for the entire population was 60 years (range, 28 to 88 years), and median tumor sizes in the two strata were 6 mm and 5 mm, respectively.ResultsWith a median follow-up of 6.2 years, the 5-year rate of ipsilateral breast events in the 565 eligible patients in the low/intermediate grade stratum was 6.1% (95% CI, 4.1% to 8.2%). With a median follow-up of 6.7 years, this incidence for the 105 eligible patients in the high-grade stratum was 15.3% (95% CI, 8.2% to 22.5%).ConclusionRigorously evaluated and selected patients with low- to intermediate-grade DCIS with margins 3 mm or wider had an acceptably low rate of ipsilateral breast events at 5 years after excision without irradiation. Patients with high-grade lesions had a much higher rate, suggesting that excision alone is inadequate treatment. Further follow-up is necessary to document long-term results.