GenesisCare UK reveals findings from interim study into spirometry-monitored DIBH
Findings from an interim study of left-sided breast cancer patients have been revealed by GenesisCare UK today, looking at the effects of radiation to the heart during and after radiotherapy treatment.
The study, which was peer-reviewed at ESTRO 2014, looked at treatment planning data from 42 left-sided breast cancer patients who were treated with spirometry-monitored deep inspiration breath-hold (DIBH) – a radiotherapy technique available in all GenesisCare UK’s centres – during 2013 and 2014. The results of the study showed that by not having DIBH, the heart can be exposed to more radiation, which can result in an increased risk of long-term cardiovascular side-effects and death.
By comparing the plans of 42 patients receiving DIBH with a comparable plan where DIBH is not used, the study illustrates a median decrease of 0.4Gy in the mean dose received by the heart for those patients receiving DIBH. Additionally, the total percentage of lung receiving the dose was also reduced, which has been investigated under another GenesisCare UK study[i].
More than 37,000 patients[ii] with breast cancer received radiotherapy in the UK in 2012 and with the support of increasingly sophisticated techniques, breast cancer survival rates are improving. But as more people live with or beyond the disease, doctors are also encountering more instances of individual’s presenting with longer-term healthcare issues as a direct consequence of the treatment that was designed to help save their lives. Spirometry-monitored DIBH has been specifically designed to alleviate these risks to patients as it moves the heart away from the radiation fields during treatment.
So far, the research suggests that spirometry-monitored DIBH has the potential to prevent two deaths and three major cardiac events per 1,000 patients treated with DIBH.
GenesisCare UK has conducted this study to monitor resulting effects on cardiac dose and cardiac risk to patients and demonstrate how DIBH can help reduce the risk of damage to vital organs and longer-term problems for the patient.
Matt Hickey, Cancer Partner UK’s Director of Clinical Outcomes, explains more about how the study has been conducted: “We compared CT scans taken from each of the 42 patients – one while the patient was free-breathing and one while the patient was performing a deep breath. Using these images, radiation delivery plans are designed against both the free-breathing and the spirometry-monitored deep-breath scans. We were then able to compare the difference between the two for each patient and draw these very powerful conclusions being announced today.”
This study supports a recent analysis of more than 30,000 women[iii] treated with radiotherapy for left-sided breast cancer, which demonstrated a three percent increase in the risk of death for every 1Gy – the basic measure of radiation dose – received by the heart. The analysis also showed that this risk
begins within the first five years after treatment and that up to 88% of patients with left-sided breast cancer treated with radiotherapy are likely to have screen-detected deformities of the cardiac muscle within the first five years after their treatment[iv][v][vi].
Furthermore, this risk is not short-term but rather continues into the third decade after treatment[vii]. Additionally, the risk is even greater in women with pre-existing cardiac risk factors e.g. smoking and obesity and further exacerbated if the woman is having other therapies that can also have negative effects on the heart e.g. anthracyclines.
Steve Bird, CEO of GenesisCare UK, commented on the study: “Our interim study indicates that spirometry-monitored DIBH is beneficial to patients with left-sided breast cancer. The short and long-term benefits for the patients with left-sided breast cancer are definitely worth considering. For insurers, this treatment could also prove to alleviate future claims and assist in making private healthcare as affordable as possible.
He continued: “At GenesisCare UK we pride ourselves on leading the industry especially when it comes to radiotherapy techniques. After assessing for each individual patient, 90% of all of our left-sided breast cancer patients have been treated with this technique.”
A whitepaper outlining these interim findings can be downloaded here and a video describing the technique can be viewed here. A Slideshare explaining the key findings can also be found here.
GenesisCare UK is developing protocols to ensure all patients treated for left-sided breast cancer with DIBH undergo a pre-participation cardiac assessment and have their blood pressure (BP), heart rate (HR) and SpO2 monitored before, during and after treatment.
GenesisCare is using the data collected from all patients treated with DIBH to continue to measure the results of this study. The cumulative results of a study of almost 300 patients will be released later this year following its inclusion in ESTRO 2015 in Barcelona which takes place 24-28 April 2015.
[i] Walsh K, Pettingell J, Kerr H, et al. How much lung is in the field? A comparison of lung depth measured in DRRs of breast tangential fields with the corresponding volume of lung receiving high doses in the DVHs of CT planned Ca Breast patients. European Society for Therapeutic Radiology and Oncology 11th Biennial Conference; 2011 May 8-12; London, UK.
[ii] Department of Health Cancer Policy. (2012): Radiotherapy Services in England 2012 https://www.gov.uk/government/uploads/system/uploads/attachment_data/fil....
[iii] Supplement to Darby SC, Ewertz M, McGale P, et al. Risk of ischemic heart disease in women after radiotherapy for breast cancer. N Engl J Med 2013;368:987-98. DOI: 10.1056/NEJMoa1209825
[iv] Darby SC, Ewertz M, McGale P, et al. Risk of ischemic heart disease in women after RT for breast cancer. N Engl J Med 2013:368:987-98.
[v] Shah. C., Badiyan. S., Berry. S., Khan. A., Goyal. S., Schulte. K.,Nanavati. A., Lynch. M., Vicini. F. (2014): Cardiac dose sparing and avoidance techniques in breast cancer radiotherapy. Radiotherapy and Oncology 112 (2014) 9–16.
[vi] Arriagada R, Averbeck D, Dahl AA, Darby S, Fosså S, Friberg S, et al. OECI Workshop on late side-effects of cancer treatments. Eur. J Cancer 2009;45(3):
[vii] Taylor C. Radiation-related heart disease following treatment for breast cancer (abstract). Radiother Oncol 2011;99:S76.