Long‐term follow‐up of a prospective policy of margin‐directed radiation dose escalation in breast‐conserving therapy

Abstract

BACKGROUND A prospectively applied treatment policy for breast‐conserving therapy used margin assessment as the exclusive guide to the intensity of radiation therapy directed at the tumor bed. METHODS From 1982 to 1994, 498 women with 509 Stage I/II breast carcinomas with a median follow‐up of 121 months were treated. Final margin status (FMS) categories were defined as greater than 5 mm, greater than 2–5 mm, greater than 0–2 mm, and positive. For margins less than or equal to 2 mm or indeterminate, reexcisions were performed if feasible. All patients received whole breast irradiation to 50.0–50.4 Gy. Final tumor bed boosts as a function of FMS were as follows: no residual on reexcision, no boost performed; FMS greater than 5 mm, boost of 10 Gy; FMS greater than 2–5 mm, boost of 14 Gy; FMS greater than 0–2 mm or positive, boost of 20 Gy. Cases were analyzed for local failure with respect to histology, age, tumor size, excision volume, reexcision, and total dose. RESULTS FMS was positive, greater than 0–2 mm, greater than 2–5 mm, and greater than 5 mm, and no residual tumor on reexcision in 21%, 20%, 17%, 14%, and 28% of cases, respectively. At 12 years, Kaplan–Meier local failure rates were 17% for FMS positive, 9% for FMS greater than 0–2 mm, 5% for FMS greater than 2–5 mm, 0% for FMS greater than 5 mm, and 6% for specimens without evidence of residuum on reexcision (P = 0.009). Patients 45 years old and younger had a 12‐year local failure rate of 15% whereas patients older than 45 years had a 12‐year local failure rate of 6% (P = 0.01). On multivariate analysis, young age (P = 0.03) predicted increased local failure rate, whereas margins that were less than or equal to 2 mm or positive predicted late (> 5 years) but not early (≤ 5 years) recurrence (P = 0.003). CONCLUSIONS Graded tumor bed dose escalation in response to FMS results in very low rates of local failure over the first 5 years for all FMS categories. However, tumors with close/positive margins have significantly increased local failure rates after 5 years of follow‐up even with increased radiation boost dose. In addition, graded tumor bed dose escalation does not fully overcome the adverse influence of young age. Cancer 2003;97:30–9. © 2003 American Cancer Society. DOI 10.1002/cncr.10981

Breast Cancer in Turkey: Clinical and Histopathological Characteristics (Analysis of 13.240 Patients)

“…In addition to the data above, in younger breast cancer patients the rate of axilla positivity and HG were higher, ER and PR positivity were lower and HER-2 positivity was also higher (17)(18)(19)(20). In our database, in patients under 40 years of age pN0 was 44%, HGIII rate was 60%, ER positivity was 61%, PR positivity was 57%, and HER-2 positivity was 26.5%, while in the more advanced aged group pN0 was 60%, HG3 rate was 44%, ER positivity was 71%, PR positivity was 59%, and HER-2 positivity was 23%.…”

Radiation therapy for operable breast cancer

“…146 The ability to achieve negative surgical margins before radiation has been identified as the most consistent factor associated with a low risk for local recurrence. 136,138,139,[147][148][149][150][151][152][153] Kurtz et al reported a 5-year local recurrence in 6% of patients with negative margins and 23% for positive margins. 136 Heimann et al reported a 5-year local recurrence in 2% with negative versus 11% with positive margins.…”

“…Young patient age was also a factor linked with increased local recurrence after BCS and radiation. 136,139,141,[152][153][154] This was suspected to be because of other adverse features in younger patients, such as EIC and high-grade disease. 136 Haffty et al reported that mammographically detected breast cancer had a trend to improved local control rates with breast-conserving surgery and radiation compared with palpable breast cancers.…”

“…The dose to the breast was 4500 cGy to 5000 cGy to the whole breast at 180 cGy to 200 cGy per day, with a tumor bed boost of 1000 cGy to 2000 cGy with electrons or, less often, interstitial implants. 145,150,152,166,174 Improvements in technique of both surgery and radiation have also been associated with good or excellent cosmetic results in over 90% to 95% of patients. 140,150 2000 to Present ''The supplementary use of local irradiation of the breast for local control is inarguable.…”

“…This has resulted in 10-to 15-year rates of local recurrence after radiation of 10%. 152,153,[176][177][178][179] BCS and radiation remain the standard alternative to mastectomy. Two prospective randomized trials were reported in Cancer in the past decade that showed equivalent long-term disease-free and overall survival.…”