Preliminary Report of Partial-breast Irradiation Following Neoadjuvant Chemotherapy from COMBAT-NEO: Clinical Outcome of Multicatheter BrAchyTherapy after NEOadjuvant Chemotherapy

Main Article Content

Kazuhiko Sato
Hiromi Fuchikami
Naoko Takeda
Takahiro Shimo
Masahiro Kato
Tomohiko Okawa


Breast-conserving therapy, Partial-breast irradiation, Neoadjuvant chemotherapy, Multicatheter-interstitial brachytherapy


Background: Breast-conserving therapy (BCT) with partial-breast irradiation (PBI) has become a standard alternative to whole-breast irradiation. Recently, neoadjuvant chemotherapy (NACT) has been widely performed for early breast cancer. Although BCT using perioperative PBI decreased invasiveness and geographic miss, risks of adverse events and local recurrence remain a concern for patients receiving NACT. Thus, a prospectively registered study, the Clinical Outcome of Multicatheter BrAchyTherapy after NEOadjuvant chemotherapy (COMBAT-NEO), was conducted.
Methods: Patients who underwent BCT using multicatheter-interstitial brachytherapy (MIB) by intraoperative catheter implant were analyzed. Early and late adverse events (AEs) including higher grade skin toxicities and wound complications, and tumor control of patients receiving NACT were evaluated in comparison with adjuvant chemotherapy (ACT) and no chemotherapy (no-CT).
Results: Between April 2017 and February 2020, 265 consecutive patients who received single-stage BCT were evaluated, including 13 NACT (4.9%), 68 ACT (25.7%), and 184 no-CT (69.4%). The median follow-up time and age were 30.0 months and 59.0 years, respectively. All patients were followed up for at least 12 months. Although AEs in NACT, ACT, and no-CT were observed in 1 (7.7%), 5 (7.4%), and 11 (6.0%) patients, respectively (p = 0.91) and there was no acute AE in NACT patients. Overall, 3 (1.1%) ipsilateral and 1 (0.4%) contralateral breast tumor recurrences were observed in no-CT patients. There were no regional and distant recurrences.
Conclusion: Although this pilot study was based on a small sample size with short follow-up, these preliminary results support the study of a single-stage BCT with MIB-PBI following NACT.


1. Hepel JT, Wazer DE. Partial breast irradiation is the preferred standard of care for a majority of women with early-stage breast cancer. J Clin Oncol. 2020;38(20):2268-2273.
2. Polgár C, Fodor J, Major T, Sulyok Z, Kásler M. Breast-conserving therapy with partial or whole breast irradiation: Ten-year results of the Budapest randomized trial. Radiother Oncol. 2013;108(2):197-202.
3. Strnad V, Ott OJ, Hildebrandt G, et al. 5-year results of accelerated partial breast irradiation using sole interstitial multicatheter brachytherapy versus whole-breast irradiation with boost after breast-conserving surgery for low-risk invasive and in-situ carcinoma of the female breast: A randomised, phase 3, non-inferiority trial. Lancet. 2016;387(10015):229-238.
4. Sato K, Shimo T, Fuchikami H, Takeda N, Kato M, Okawa T. Predicting adherence of dose–volume constraints for personalized partial-breast irradiation technique. Brachytherapy. 2021;20(1):163-170.
5. Cambeiro M, Martinez-Regueira F, Rodriguez-Spiteri N, et al. Multicatheter breast implant during breast conservative surgery: Novel approach to deliver accelerated partial breast irradiation. Brachytherapy. 2016;15(4):485-494.
6. Cozzi S, Laplana M, Najjari D, et al. Advantages of intraoperative implant for interstitial brachytherapy for accelerated partial breast irradiation either frail patients with early-stage disease or in locally recurrent breast cancer. J Contemp Brachytherapy. 2018;10(2):97-104.
7. Sato K, Fuchikami H, Takeda N, Kato M, Shimo T, Okawa T. Validating the ef fi cacy of single-stage breast- conserving therapy using multicatheter partial-breast brachytherapy based on updated ASTRO guidelines. 2018;59(3):303-308.
8. Zur M, Shai A, Leviov M, et al. Short-term complications of intra-operative radiotherapy for early breast cancer. J Surg Oncol. 2016;113(4): 370-373.
9. Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials - The Lancet. Accessed March 27, 2021.
10. Volders JH, Negenborn VL, Spronk PE, et al. Breast-conserving surgery following neoadjuvant therapy-a systematic review on surgical outcomes. Breast Cancer Res Treat. 2018;168(1).
11. Masuda N, Lee S-J, Ohtani S, et al. Adjuvant Capecitabine for Breast Cancer after Preoperative Chemotherapy. N Engl J Med. 2017;376(22):2147-2159.
12. von Minckwitz G, Huang C-S, Mano MS, et al. Trastuzumab Emtansine for Residual Invasive HER2-Positive Breast Cancer. N Engl J Med. 2019;380(7):617-628.
13. Heil J, Kuerer HM, Pfob A, et al. Eliminating the breast cancer surgery paradigm after neoadjuvant systemic therapy: current evidence and future challenges. Ann Oncol. 2020; 31(1):61-71.
14. Sato K, Fuchikami H, Takeda N, Shimo T, Kato M, Okawa T. Efficacy of Single-Plane Implant Technique in Partial Breast Brachytherapy in Small-Breasted Patients. Int J Radiat Oncol Biol Phys. 2020;106(4):830-837.
15. Asselain B, Barlow W, Bartlett J, et al. Long-term outcomes for neoadjuvant versus adjuvant chemotherapy in early breast cancer: meta-analysis of individual patient data from ten randomised trials. Lancet Oncol. 2018;19(1):27-39.
16. Sato K, Fuchikami H, Takeda N, Shimo T, Kato M, Okawa T. Moving incision for covert breast-conserving surgery may prevent early wound complications in brachytherapy-based partial-breast irradiation. Brachytherapy. 2019;18(5):645-650.
17. Sato K, Shimo T, Fuchikami H, Takeda N, Kato M, Okawa T. Catheter-based delineation of lumpectomy cavity for accurate target definition in partial-breast irradiation with multicatheter interstitial brachytherapy. J Contemp Brachytherapy. 2019;11(2):108-115.
18. Budd GT, Barlow WE, Moore HCF, et al. SWOG S0221: A phase III trial comparing chemotherapy schedules in high-risk early-stage breast cancer. J Clin Oncol. 2015;33(1):58-64.
19. Jones S, Holmes FA, O’Shaughnessy J, et al. Docetaxel with cyclophosphamide is associated with an overall survival benefit compared with doxorubicin and cyclophosphamide: 7-year follow-up of us oncology research trial 9735. J Clin Oncol. 2009;27(8):1177-1183.
20. Vaidya JS, Joseph DJ, Tobias JS, et al. Targeted intraoperative radiotherapy versus whole breast radiotherapy for breast cancer (TARGIT-A trial): An international, prospective, randomised, non-inferiority phase 3 trial. Lancet. 2010;376(9735): 91-102.
21.Common Terminology Criteria for Adverse Events (CTCAE) | Protocol Development | CTEP. Accessed March 27, 2021.
22. National Nosocomial Infections Surveillance (NNIS) System Report, data summary from January 1992 through June 2004, issued October 2004. Am J Infect Control. 2004;32(8):470-485.
23. Kurtz JM, Amalric R, Brandone H, et al. Local recurrence after breast?conserving surgery and radiotherapy. Frequency, time course, and prognosis. Cancer. 1989;63(10):1912-1917.
24.Schmid P, Cortes J, Pusztai L, et al. Pembrolizumab for Early Triple-Negative Breast Cancer. N Engl J Med. 2020;382(9):810-821.
25. Heil J, Sinn P, Richter H, et al. RESPONDER - diagnosis of pathological complete response by vacuum-assisted biopsy after neoadjuvant chemotherapy in breast Cancer - a multicenter, confirmative, one-armed, intra-individually-controlled, open, diagnostic trial. BMC Cancer. 2018;18(1).
26.Kaidar-Person O, Meattini I, Zippel D, Poortmans P. Apples and oranges: comparing partial breast irradiation techniques. Reports Pract Oncol Radiother. 2020;25(5):780-782.
27. Keisch M, Vicini F, Beitsch P, et al. American Society of Breast Surgeons MammoSite Radiation Therapy System Registry Trial: ductal carcinoma-in-situ subset analysis-4-year data in 194 treated lesions. Am J Surg. 2009; 198(4):505-507.

Article Statistics :Views : 177 | Downloads : 140 : 3