November 5, 2020
Study finds that every month delay in cancer treatment can raise risk of death by around 10 per cent
Research led by Dr. Timothy Hanna suggests that minimizing delays to treatment could improve cancer survival rates
Many countries have needed to defer cancer surgeries, radiotherapy and other treatments through the COVID-19 pandemic, which has brought the impact of treatment delays into sharp focus. In a study published today in The BMJ, Dr. Timothy Hanna and collaborators report that people whose cancer treatment is delayed by even four weeks have in many cases a six to 13 per cent higher risk of dying – a risk that keeps rising the longer their treatment does not begin.
“We know that delay matters and now we understand how much it matters,” says Hanna, Radiation Oncologist at the Cancer Centre of Southeastern Ontario, Faculty of Queen’s Cancer Research Institute, OICR Clinician Scientists and lead of the study. “With these data, we can now quantify the impact of treatment delays – including those that we’re experiencing now throughout the COVID-19 pandemic.”
The research group reviewed and analyzed relevant studies from around the world that were published over the last two decades. They found that there was a significant impact on a person’s risk of death if their treatment was delayed, whether the treatment was surgical, chemotherapy or radiotherapy. They observed this impact across all seven types of cancer analyzed – breast, bladder, colon, rectum, lung, cervix and head and neck cancers.
For example, with cancer surgery, they saw a six to eight per cent increase in the risk of death for every four-week treatment delay, meaning that a three-month delay could increase the risk of death by about 25 per cent. The impact was even greater for specific treatments – such as bowel cancer chemotherapy – where a three-month delay could cause a 44 per cent increase in risk of death.
“As we move towards the second COVID-19 wave in many countries, the results emphasize the need to prioritize cancer services including surgery, drug treatments and radiotherapy as even a four-week delay can significantly increase the risk of cancer death,” says Dr. Ajay Aggarwal, co-lead of the study from King’s College London and the London School of Hygiene and Tropical Medicine.
Hanna hopes this study will help inform cancer treatment backlog management and prioritization. His prior work on prioritizing treatment during COVID-19, published in Nature Reviews Clinical Oncology, has been incorporated into health system planning and management in Ontario and around the world.
“The impact of cancer treatment delays will persist long after the threat of this pandemic subsides,” says Hanna. “As a clinician, a patient, an administrator or a decision-maker in our cancer care system, these results should encourage us all to put resources and efforts in place to minimize system level delays in cancer treatment.”
April 11, 2019
Research group identifies the nuanced barriers that prevent patients from following up on a positive colorectal cancer screening test
Colorectal cancer (CRC) is often detectable and beatable, yet it still remains the second leading cause of cancer-related death in Canada. Ontario offers an at-home CRC screening test, however not all patients who have abnormal test results receive the necessary follow-up care due to a number of factors. This means that there are missed opportunities to treat – and cure – some of these cancers.
Dr. Jill Tinmouth at the Sunnybrook Research Institute has set out to improve follow-up after a positive CRC screening test. The first step, Tinmouth says, is to understand why patients may be reluctant to follow up in the first place.
“The screening test for colorectal cancer is an easy, safe, painless, at-home fecal occult blood test (FOBT) but without proper follow-up of abnormal tests, it is all for naught,” says Tinmouth. The FOBT checks a person’s stool for tiny drops of blood, which can be caused by CRC. Colonoscopy is the recommended next step for anyone who has an abnormal FOBT. “Looking at the administrative data, we saw that nearly one in three people with an abnormal FOBT don’t follow up with colonoscopy within six months. We are working to both understand and fix this gap.”
In this first study, Tinmouth and collaborators looked into Ontario’s administrative health data to try to improve the lack of follow-up. These initial findings suggested that physicians may not be adhering to screening guidelines and led to better articulation of CRC screening and follow-up protocols to primary care providers.
“We made some modifications to our screening program to encourage physicians to follow up on positive FOBT results in a timely manner, but we recognized that these strategies wouldn’t solve every problem,” says Tinmouth. “To fully understand the gaps and barriers to following up, we knew we had to speak directly to patients and those in this position.”
In their most recent study on the subject, published in the American Journal of Gastroenterology, Tinmouth teamed up with Dr. Diego Llovet from Cancer Care Ontario to interview patients who failed to follow-up on positive FOBT results and physicians who care for those patients. Many of the patients believed that their test results were a false positive and others experienced fear, anxiety or uneasiness about the next step in CRC screening – a colonoscopy. Often, patients were reluctant to have a colonoscopy and physicians were unable to persuade their patients to follow through.
Tinmouth is now working with health system decision-makers and Cancer Care Ontario to test and pilot four different interventions that could help improve proper follow-up, including patient navigation through the screening process and reminders sent to physicians of patients who test positive but fail to follow up. This research group is evaluating the feasibility of these interventions and how Ontario could implement them across the province.
“Better colon cancer screening and care starts with understanding the barriers and then effectively implementing this new knowledge,” says Tinmouth. “On these projects, researchers worked hand-in-hand with policy-makers – in so doing, we were able to integrate our expertise and collective wisdom to improve colorectal cancer screening for Ontarians today and in the future.”
December 17, 2018
Large-scale genomic study discovers 40 new genetic variants associated with colorectal cancer risk
The most comprehensive genome-wide association study of colorectal cancer risk to date has discovered 40 new genetic variants and validated 55 previously identified variants that signal an increased risk of colon cancer. The study, recently published in Nature Genetics, is a product of the world’s largest molecular genetic consortium for colorectal cancer – the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO) – which was established nearly 10 years ago.Continue reading – When it comes to finding cancer risk, there’s power in numbers
May 13, 2016
The University Health Network announced today that Dr. Geoffrey Liu, clinician-scientist at Princess Margaret Cancer Centre, and his team have identified a blood marker that better defines which patients will respond to the drug cetuximab. The research applies to patients with metastatic colorectal cancer.
See Dr. Liu explain his findings:
Dr. Liu’s research was funded by the Ontario Institute of Cancer Research, the Alan B. Brown Chair in Molecular Genomics, the Cancer Care Ontario Chair in Experimental Therapeutics and Population Studies, the Canadian Cancer Society, and The Princess Margaret Cancer Foundation. The research was published today in the journal Clinical Cancer Research.