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The role of boost irradiation in the conservative treatment of stage I-II breast cancer

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  • Published:
Pathology & Oncology Research

Abstract

In this article, we review the current status, indication, technical aspects, controversies, and future prospects of boost irradiation after breast conserving surgery (BCS). BCS and radiotherapy (RT) of the conserved breast became widely accepted in the last decades for the treatment of early invasive breast cancer. The standard technique of RT after breast conservation is to treat the whole breast up to a total dose of 45 to 50 Gy. However, there is no consensus among radiation oncologists about the necessity of boost dose to the tumor bed. Generally accepted criteria for identification of high risk subgroups, in which boost is recommended, have not been established yet. Further controversy exists regarding the optimal boost technique (electron vs. brachytherapy), and their impact on local tumor control and cosmesis. Based on the results of numerous retrospective and recently published prospective trials, the European brachytherapy society (GEC-ESTRO), as well as the American Brachytherapy Society has issued their guidelines in these topics. These guidelines will help clinicians in their medical decisions. Some aspects of boost irradiation still remain somewhat controversial. The final results of prospective boost trials with longer follow-up, involving analyses based on pathologically defined subgroups, will clarify these controversies. Preliminary results with recently developed boost techniques (intraoperative RT, CT-image based 3D conformal brachytherapy, and 3D virtual brachytherapy) are promising. However, more experience and longer follow-up are required to define whether these methods might improve local tumor control for breast cancer patients treated with conservative surgery and RT.

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Abbreviations

ABS:

American Brachytherapy Society

BCS:

breast conserving surgery

BT:

brachytherapy

CT:

computer tomograph

DBCG:

Danish Breast Cancer Group

EIC:

extensive intraductal component

EORTC:

European Organization for Research and Treatment of Cancer

GEC-ESTRO:

Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology

HDR:

high dose rate

HG:

histological grade

IGR:

Institut Gustav-Roussy

ILC:

infiltrating lobular carcinoma

IORT:

intraoperative radiation therapy

LDR:

low dose rate

LTC:

local tumor control

L:

lumpectomy

LVI:

lympho-vascular invasion

MRI:

magnetic resonance imaging

NCI:

National Cancer Institute

NSABP:

National Surgical Adjuvant Breast and Bowel Project

Q:

quadrantectomy

RFS:

relapse-free survival

RR:

relative risk

RT:

radio-therapy

TE:

tumorectomy

3D:

three dimensional

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Authors and Affiliations

  1. Department of Radiotherapy, National Institute of Oncology, Ráth György u. 7-9, H-1122, Budapest, Hungary

    Csaba Polgár, János Fodor, Tibor Major & György Németh

  2. Department of Pathology, National Institute of Oncology, Budapest, Hungary

    Zsolt Orosz

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  1. Csaba Polgár
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  2. János Fodor
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  3. Tibor Major
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  4. Zsolt Orosz
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  5. György Németh
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Correspondence to Csaba Polgár.

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Polgár, C., Fodor, J., Major, T. et al. The role of boost irradiation in the conservative treatment of stage I-II breast cancer. Pathol. Oncol. Res. 7, 241–250 (2001). https://doi.org/10.1007/BF03032380

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