ACCELERATED PARTIAL BREAST IRRADIATION WITH INTERSTITIAL IMPLANTS: RISK FACTORS ASSOCIATED WITH INCREASED LOCAL RECURRENCE

作者：Ott Oliver J^*; Hildebrandt Guido; Poetter Richard; Hammer Josef; Hindemith Marion; Resch Alexandra; Spiegl Kurt; Lotter Michael; Uter Wolfgang; Kortmann Rolf Dieter; Schrauder Michael; Beckmann Matthias W; Fietkau Rainer; Strnad Vratislav

来源：International Journal of Radiation Oncology, Biology, Physics, 2011, 80(5): 1458-1463.

DOI：10.1016/j.ijrobp.2010.04.032

• Accelerated partial breast irradiation
• Local control
• In-breast recurrence
• Interstitial brachytherapy
• Risk factors

Purpose: To analyze patient, disease, and treatment-related factors regarding their impact on local control after interstitial multicatheter accelerated partial breast irradiation (APBI).
Methods and Materials: Between November 2000 and April 2005, 274 patients with early breast cancer were recruited for the German Austrian APBI Phase II trial (ClinicalTrials.gov identifier: NCT00392184). In all, 64% (175/274) of the patients received pulsed-dose-rate (PDR) brachytherapy and 36% (99/274) received high-dose-rate (HDR) brachytherapy. Prescribed reference dose for HDR brachytherapy was 32 Gy in eight fractions of 4 Gy, twice daily. Prescribed reference dose in PDR brachytherapy was 49.8 Gy in 83 consecutive fractions of 0.6 Gy each hour. Total treatment time was 3 to 4 days.
Results: The median follow-up time was 64 months (range, 9-110). The actuarial 5-year local recurrence free survival rate (5-year LRFS) was 97.7%. Comparing patients with an age <50 years (49/274) vs. >= 50 years (225/274), the 5-year LRFS resulted in 92.5% and 98.9% (exact p = 0.030; 99% confidence interval, 0.029-0.032), respectively. Antihormonal treatment (AHT) was not applied in 9% (24/274) of the study population. The 5-year LRFS was 99% and 84.9% (exact p = 0.0087; 99% confidence interval, 0.0079-0.0094) in favor of the patients who received AHT. Lobular histology (45/274) was not associated with worse local control compared with all other histologies (229/274). The 5-year LRFS rates were 97.6% and 97.8%, respectively.
Conclusions: Local control at 5 years is excellent and comparable to therapeutic successes reported from corresponding whole-breast irradiation trials. Our data indicate that patients <50 years of age ought to be excluded from APBI protocols, and that patients with hormone-sensitive breast cancer should definitely receive adjuvant AHT when interstitial multicatheter APBI is performed. Lobular histology need not be an exclusion criterion for future APBI trials.

• 出版日期2011-8-1