The Persephone clinical trial set out to establish whether 6 months treatment with Herceptin is as effective as 12 months for women with early HER2+ breast cancer.
I was diagnosed HER2+ in 2012 and should point out I quickly established Googling HER2+ can scare you senseless. Almost everything I read suggested my situation was bleak. Looking back, I wish I hadn’t found those articles before talking to my consultant. They created unnecessary stress at a time that was already stressful enough.
My consultant didn’t deny the challenges of HER2+ breast cancer but she strongly emphasised a new monoclonal antibody treatment called Herceptin. In her view it improved the outlook for HER2+ patients considerably, but Google articles had yet to catch up with those developments.
If surgery was followed with chemotherapy and Herceptin, early HER2+ breast cancer was probably as treatable as hormone positive breast cancer. I was lucky – in 2012 Herceptin had only just been approved for people like me and without it I might not have been here to write this post!
I cannot deny chemotherapy was something I hoped to avoid. My aunt and mother went through it but neither survived cancer. Once again my consultant offered helpful advice: chemotherapy and Herceptin could help prevent metastases. No one dies of early breast cancer and for early breast cancer patients, the key to survival is preventing metastases. My loved ones didn’t get that chance, they both had metastases and these treatments weren’t available in the 1980’s and 90’s.
I was prescribed FEC-TH, the namesake of this blog and one of the most effective chemotherapy regimes for my particularly aggressive form of cancer. It was an adjuvant (post-surgery) therapy involving several rounds of intravenous anthracyclines followed by a concurrent taxane plus Herceptin protocol, then Herceptin on its own. At the point of consent, my oncologist asked if I’d participate in clinical trials. Breast cancer wiped out at least five generations of women in my family, all below the age of 50. It really is our family curse. Volunteering for trials was therefore quite easy and even if trials couldn’t help me, the prospect of results that might benefit future generations provided something positive to hold on to during a very turbulent period. Without hesitation, my participation in the Persephone Trial began.
Information about trials
Doctors are obliged to provide lots of information because taking part in a trial means trying something new and unproven. The first thing I had to do was read and digest the information about Persephone and there was quite a lot of it. It told me there could be risks, for example if I was randomised into the 6 month treatment group and this proved inferior to 12 months treatment, the likelihood of cancer returning might be increased. It explained possible benefits too, for example if 6 months treatment was as effective as 12 months in dealing with cancer, it could reduce the risk that I’d suffer heart damage or a serious cardiac event. (Herceptin and anthracyclines can damage the heart, sometimes irreparably). The information also made it clear that if I was randomised into the 6 month group and decided to change my mind, I could withdraw and receive the full 12 months of Herceptin treatment. Throughout the trial I’d be closely monitored and if I had any problems at all, I could contact people who’d be able to help.
There was a lot of detail and a lot to weigh up, so if you’re considering taking part in a clinical trial, I recommend reading the information all the way through. Then read it again, making notes on anything you’d like your doctor or trial coordinator to explain. There are no silly questions so ask whatever you need to know or are concerned about. None of us is forced to participate in trials, but for some of us personal history or exhausting the existing range of treatments makes trials the obvious or only option. In a best case scenario, we benefit as trial participants and the research we contribute to also goes on to benefit future generations.
Follow-up during treatment
I was carefully monitored throughout the trial as well as receiving the same excellent standard of care as non-trials patients. In addition, every three weeks I completed a questionnaire summarising my experiences, sense of well-being, impact of treatment on my general health, any side-effects I’d had, and the financial impact of my treatment. Financial impacts for patients are all too often overlooked – I was glad Persephone included this alongside the clinical factors. Herceptin caused some problems for me and at one point my treatment was delayed. Fortunately this didn’t prevent me continuing in the trial. Your medical team will be able to tell you what the follow-up involves and how the information is used if you consider taking part in a clinical trial.
Follow-up after treatment
In May this year, Persephone reported on its initial findings after four years follow-up with the original trial patients. I was sent information about the results over the summer. My oncologist will follow-up with me for 10 years because I’ve been a trials patient and further reports from the Persephone study might be published along the way or shortly after the 10 year point. Although I’m past the five year ‘no evidence of disease’ milestone which can be significant in early HER2+ breast cancer, returning to the chemotherapy centre still makes me apprehensive. To avoid becoming a jibbering wreck immediately prior to each visit, I’ve convinced myself the extended follow-up period is a good thing. Having someone who really understands cancer keeping an eye on me and knowing they’ll take action if anything remotely suspicious shows up provides a degree of comfort.
This extended period of follow-up also lends itself to some of the commentary about the Persephone trial. One of the areas of uncertainty is the current four-year follow-up. Four years may not be long enough to fully understand the benefits of a six month treatment regime in preventing reoccurrence or distant metastases because cancer can reoccur many years later. (Most but not all HER2+ reoccurrences happen within 5 years).
Outcome of the trial
I’m encouraged and enthusiastic about this, and although my oncologist is deeply scientific (=immune to any high jinks), initial results for some groups of patients made him enthusiastic too.
Over 4000 women with early stage HER2+ breast cancer took part in the Persephone trial and a full article on the research and its outcomes is available here. The National Institute for Health Research (NIHR) reported “89.4% of patients taking six months treatment were free of disease after four years compared with 89.8% of patients taking twelve months of treatment. This shows six months of treatment is as effective as twelve for many women. In addition, only 4% of women in the six month arm stopped taking the drug early because of heart problems compared with 8% in the twelve month arm.”
The NIHR report goes on to say further analysis of tumour and blood samples from trial participants will help researchers understand which women can stop Herceptin at six months, and which women need extended treatment.
Herceptin has already improved the outlook for people with early-stage HER2+ breast cancer. Further information about its impact is available here if you want to see some statistics, but please bear in mind cancer is unpredictable and none of us is purely a statistic.
If the Persephone trial concludes some people can safely receive a shorter treatment regime offering the same cancer survival benefits and a significantly reduced risk of heart damage or serious cardiac events then I’m really glad I took part. Doctors sometimes struggle to find enough patients who are willing to participate in clinical trials. As a patient it can be a daunting prospect. For me, family history and taking part in something with the potential to improve treatment for countless other people as well as myself was the most significant and influential factor.