The use of an interstitial boost in the conservative treatment of breast cancer: how to perform it routinely in a radiotherapy department.
J Contemp Brachytherapy 2014;
6:397-403. [PMID:
25834585 PMCID:
PMC4300358 DOI:
10.5114/jcb.2014.46757]
[Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 09/26/2014] [Accepted: 10/22/2014] [Indexed: 11/17/2022] Open
Abstract
Purpose
To demonstrate the utility of a boost with interstitial brachytherapy (BT) in breast-conserving therapy (BCT) by doing a thorough review of the literature and describing in detail our technique for delivering this boost.
Material and methods
Our department has been delivering the boost with interstitial BT since 1989, in most cases with rigid needles and a theoretical dosimetry. In the early years, we used low-dose-rate (LDR) with iridium-192 wires. The dose administered was 15 Gy if there were no risk factors for local relapse or 20-25 Gy in the presence of risk factors. The risk factors considered were the presence of a close margin (less than 10 mm) and an extensive intraductal component (more than 25%). After 2002, we switched to high-dose-rate (HDR); using the linear quadratic model we changed the low dose to 3 fractions of 4.5 Gy in the case of no risk factors for local relapse or to 3 fractions of 5 Gy in the presence of risk factors.
Results
In 79 consecutive boost patients treated in our department between 2010 and 2011, with a median follow-up of 46 months, the local control rate was 97.47%. With respect to cosmesis, fibrosis occurred in 17 cases (21.5%) and hyperpigmentation in 26 cases (32.9%). Our hospital's results are comparable in terms of local control and cosmesis to those of other authors.
Conclusions
This educational article describes our department's boost technique with rigid needles and comments briefly on our results using this technique in a group of consecutively treated patients in our department. A review of the literature and the published results on local control and cosmesis is also described.
Collapse