Long term results of a phase II trial of hypofractionated adjuvant radiotherapy for early-stage breast cancer with volumetric modulated arc therapy and simultaneous integrated boost. (November 2021)

• Record Type: Journal Article
• Authors: Franceschini, D.; Fogliata, A.; Spoto, R.; Dominici, L.; Lo Faro, L.; Franzese, C.; Comito, T.; Lobefalo, F.; Reggiori, G.; Cozzi, L.; Sagona, A.; Gentile, D.; Scorsetti, M.
• Is Part Of: Radiotherapy and oncology. Volume 164(2021)
• Page Start: 50
• Page End: 56
• Publication Date: 2021-11
• Subjects: VMAT Volumetric modulated arc therapy -- SIB Simultaneous integrated boost -- RT Radiotherapy -- IMRT Intensity-modulated radiotherapy -- 3D-CRT 3 dimensional conformal radiotherapy -- DCIS Ductal carcinoma in situ -- CT Computed tomography -- AJCC American Joint Committee on Cancer -- CTV Clinical target volume -- PTV Planning target volume -- MLC Multi-leaf collimator -- CBCT Cone-beam computed tomography -- RTOG Radiation Therapy Oncology Group -- CTCAE Common Terminology Criteria for Adverse Events -- DVH Dose-volume histogram -- OAR Organ at risk -- OS Overall survival -- DSFS Disease-specific free survival -- ALARA As low as reasonably achievable; Early-stage breast cancer -- Simultaneous integrated boost -- SIB -- Hypofractionation -- VMAT -- Late toxicity; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2021.09.006
• Languages: English
• ISSNs: 0167-8140

Abstract

Highlights: Results from an early-stage breast cancer trial with VMAT in hypofractionated SIB. 450 patients were included in the trial with median follow-up of 6 years. Late toxicity and cosmesis showed good results. Recurrence, new breast tumour, metastasis developed in 1.8%, 1.1%, 2.2% of patients. Abstract: Purpose: to report toxicity and cosmetic outcome with a median follow-up of 6 years of a phase II trial of hypofractionated radiotherapy with volumetric modulated arc therapy (VMAT) and simultaneous integrated boost (SIB) for early-stage breast cancer after conservative surgery. Materials and methods: From August 2010 to September 2014, patients requiring adjuvant radiotherapy for early-stage breast cancer were treated according to a phase I–II protocol with SIB to 40.5 and 48 Gy to the breast and the boost region, respectively, with VMAT technique. The primary endpoint evaluated the treatment feasibility regarding adherence to required dose constraints for target, heart and lungs. Acute and late toxicity, local and distant control were secondary endpoints. Results: 450 patients were included in the trial and analysed after a median follow-up of 6 years. Acute toxicity was already presented in a previous paper. Regarding late toxicity, 93% of patients had no skin alteration at five years, while 5.3% and 1.3% did record G1 and G2 residual toxicity, respectively. Cosmetic outcome was scored good or excellent in almost all cases (97.2%), fair only in 2.3% of patients. Residual tenderness in the irradiated breast was reported by 10% of patients. Cosmesis and breast pain improved during follow-up. Two cases of G2 pneumonitis and two cases of ischemic cardiopathy were registered during follow-up. Five cases presented local recurrence in the homolateral breast, four patients had a new primary cancer in the contralateral breast, while distant metastasis developed in 7 patients. Conclusion: After more than six years, hypofractionated VMAT with SIB for adjuvant radiotherapy in early-stage breast cancer patients remains a safe and effective approach. Mature data on skin toxicity and cosmetic outcome are encouraging. However, longer follow-up is required to evaluate local control, cardiac toxicity and secondary carcinogenesis.