Important Canadian study examines impact of cancer care organization and delivery on breast cancer death rate
A first-ever study of how evolving diagnostic and therapy guidelines in conjunction with community programs affect breast cancer population mortality found a possible link between death rates and the way cancer care is organized. Although the breast cancer death rate declined substantially in Canada during the study period, different levels of mortality reduction were seen in different provinces and age groups.
Breast cancer is the most commonly diagnosed cancer in women. An estimated 21,200 cases will be diagnosed in Canada this year, and over 5,000 women will die of the disease.
"Breast cancer mortality declined in Canada during the study period, as it did in the rest of the Western world," Dr. Ragaz said. "This is probably thanks to a combination of improvements in treatment, mammography screening and better education. However, regional variations in mortality reduction were observed. One of the factors could be different rates of disseminating cancer care guidelines.
"Our goal was to document the impact of cancer diagnostic and therapeutic guidelines, and of community programs, that evolved in Canada between the late 1970s and early 2000s on how many women actually died from breast cancer each year since 1970, and whether there were differences in the provinces which could be linked to the organization of cancer care, its funding, etc.," says the study's principal investigator, Dr. Joseph Ragaz, Director, Oncology, of the McGill University Health Centre (MUHC).
The earliest and most dramatic reductions in breast cancer mortality were seen in British Columbia, the Canadian province with the most comprehensive cancer guidelines and community programs in existence since the 1970s, at least a decade or two earlier than in the rest of the Canadian provinces.
Canada offers an ideal model to test the impact of cancer care organization, because guidelines and programs vary widely from region to region. Organizational and funding infrastructures for cancer care programs are also different from province to province.
Overall, the results are encouraging, according to Dr. Ragaz. "In Canada, we have seen a 10 to 20 percent reduction in breast cancer deaths during the last two decades. This translates into between 500 and 1,000 lives saved each year compared to the 1970s, by improved diagnosis and treatment.
"Generating superior results from clinical trials is a pivotal first step in reducing the overall death rate from breast cancer," he adds. "However, while new research suggests better ways to treat cancer, improved therapies will only have a large-scale impact if they are translated into treatment guidelines and community programs which affect the entire patient population, if differences between larger centres and rural communities are abolished, with equal cancer care delivered to everybody at any time. These are the main conclusions of our study," Dr. Ragaz emphasized.
Results of the study by Dr. Ragaz and his colleagues were presented recently at the 2004 meeting of the European Society of Medical Oncologists (ESMO) in Vienna, and were called an important development, identifying both the cancer research and cancer organization in the communities as essential.
The results were especially appropriate as the European community is in the process of developing guidelines and community programs for large segments and different European countries in a similar way to that which had been implemented in British Columbia over the last two decades.
ESMO is Europe's leading professional society, providing education and clinical guidelines for medical oncologists and other health care professionals working to ensure optimal care for cancer patients. At ESMO 2004, more than 8,000 physicians and scientists attended over 500 presentations on the latest developments in cancer research, diagnosis and treatments.