Intraoperative radiation therapy deserves to be made more readily available to patients
Editorial

Intraoperative radiation therapy deserves to be made more readily available to patients

Mohammed Keshtgar, Norman R. Williams

The Breast Unit, Royal Free Hospital, Royal Free London Foundation Trust, Hampstead, London NW3 2QG, UK

Correspondence to: Norman R. Williams, PhD, Principal Research Associate. The Breast Unit, Royal Free Hospital, Royal Free London Foundation Trust, Pond Street, Hampstead, London NW3 2QG, UK. Email: norman.williams@ucl.ac.uk.

Submitted Jan 18, 2016. Accepted for publication Feb 01, 2016.

doi: 10.21147/j.issn.1000-9604.2016.04.10

Whole breast external beam radiotherapy is an effective adjuvant treatment for early breast cancer,and was a key factor in the move from mastectomy to breast-conserving surgery for women with low-risk disease. The logical development from partial surgical removal of the breast is partial breast radiotherapy. Several methods of delivery have been investigated,but as yet none has been widely accepted.

The article by Vincent Vinh-Hung and colleagues describes very well their experience with the use of a single dose of low kilovoltage X-rays delivered intra-operatively from within the breast using Intrabeam® (the TARGIT technique) (1). Although the results are from a single site with a relatively small number of patients and short follow-up (median 370 days),their data are consistent with the results from the short and intermediate term (median 2.4 y) follow-up data from the TARGIT A randomised controlled trial (2). In particular,it is noteworthy that the reported toxicities with Intrabeam® are less than the institution's own retrospective control group that received external beam radiotherapy.

It has been shown that TARGIT can be applied to a large proportion of patients with early breast cancer,either as sole (TARGIT alone) or as a replacement for the tumour-bed boost (TARGIT boost) (3),regardless of age (4). This is important,as evidence is growing for the long-term toxicities of whole-breast radiotherapy,as normal tissues are inevitably exposed to radiation. For example,conventional radiotherapy delivers a mean dose of 5.2 Gy to the heart (5). Even with modern radiotherapy techniques,the heart receives an appreciable dose of radiation. Mean heart dose for intensity modulated radiotherapy (IMRT) was 12.9±3.9 vs. 4.5±2.4 Gy for 3D conformal radiation therapy (3DCRT). Heart volumes receiving >40 Gy were 2.6% (3DCRT) vs. 1.3% (IMRT); doses were >50 Gy with 3DCRT (6). Breath-holding techniques and prone positioning of the patient are effective and can reduce the volume of heart in the radiotherapy field,but there is limited data on late cardiac events (7). Even a single fraction of external beam radiotherapy can produce measurable changes to the DNA of circulating lymphocytes (8). Exposing women with small,focal,screen-detected lesions to these risks should be questioned more widely.

There are several other reasons why the use of Intrabeam® should be considered; for reviews,see (9-11). Ultimately,we agree with the author's final sentence: "The technique deserves to be made more readily available to our patients."

Acknowledgements

None.

Footnote

Conflicts of Interest: The authors have no conflicts of interest to declare.

References

  1. Vinh-Hung V, Nepote V, Rozenholc A, et al. First year experience with IORT for breast cancer at the Geneva University Hospitals.  Transl Cancer Res 2014;3:65–73.
  2. Vaidya JS, Joseph DJ, Tobias JS, et al. Targeted intra-operative radiotherapy versus whole breast radiotherapy for breast cancer (TARGIT-A trial): an international, prospective, randomised, non-inferiority phase 3 trial. Lancet 2010;376:91–102. [PubMed] DOI:10.1016/S0140-6736(10)60837-9
  3. Sperk E, Astor D, Keller A, et al. A cohort analysis to identify eligible patients for intraoperative radiotherapy (IORT) of early breast cancer. Radiat Oncol 2014;9:154. [PubMed] DOI:10.1186/1748-717X-9-154
  4. Abbott AM, Dossett LA, Loftus L, et al. Intraoperative radiotherapy for early breast cancer and age: clinical characteristics and outcomes. Am J Surg 2015;210:624–8. [PubMed] DOI:10.1016/j.amjsurg.2015.05.012
  5. Taylor CW, Wang Z, Macaulay E, et al. Exposure of the heart in breast cancer radiation therapy: A systematic review of heart doses published during 2003 to 2013. Int J Radiat Oncol Biol Phys 2015;93:845–53. [PubMed] DOI:10.1016/j.ijrobp.2015.07.2292
  6. Heggemann F, Grotz H, Welzel G, et al. Cardiac function after multimodal breast cancer therapy assessed with functional magnetic resonance imaging and echocardiography imaging. Int J Radiat Oncol Biol Phys 2015;93:836–44. [PubMed] DOI:10.1016/j.ijrobp.2015.07.2287
  7. Shah C, Badiyan S, Berry S, et al. Cardiac dose sparing and avoidance techniques in breast cancer radiotherapy. Radiother Oncol 2014;112:9–16. [PubMed] DOI:10.1016/j.radonc.2014.04.009
  8. Woolf DK, Williams NR, Bakshi R, et al. Biological dosimetry for breast cancer radiotherapy: a comparison of external beam and intraoperative radiotherapy. Springerplus 2014;3:329. [PubMed] DOI:10.1186/2193-1801-3-329
  9. Keshtgar M, Davidson T, Pigott K, et al. Current status and advances in management of early breast cancer. Int J Surg 2010;8:199–202. [PubMed] DOI:10.1016/j.ijsu.2010.02.004
  10. Williams NR, Pigott KH, Keshtgar MR. Intraoperative radiotherapy in the treatment of breast cancer: a review of the evidence.  Int J Breast Cancer 2011;2011:375170. [PubMed]
  11. Williams NR, Pigott KH, Brew-Graves C, et al. Intra-operative radiotherapy for breast cancer. Gland Surg 2014;3:109–19.
    12. Cite this article as: Keshtgar M, Williams NR. Intraoperative radiation therapy deserves to be made more readily available to patients. Chin J Cancer Res 2016;28(4):461-462. doi: 10.21147/j.issn.1000-9604.2016.04.10