November is lung cancer awareness month. As part of an ongoing series on lung cancer, BC Cancer is sharing information and insights into how this disease is affecting British Columbians, what the risk factors are and how they can be prevented, and the importance of early detection for those with high risk.
Lung cancer is the leading cause of cancer related deaths in B.C. and across Canada. On average, there are 3,400 new cases of lung cancer every year in the province with almost half diagnosed at Stage 4, where the cancer has spread beyond the lungs. In B.C., there are some noticeable trends in the rates of new cases for this cancer according to Jonathan Simkin, Scientific Director of the BC Cancer Registry, and Dr. Ryan Woods, Director of Data & Analytics at BC Cancer.
“Although overall the rate of new lung cancer cases is declining in B.C., we have observed that lung cancer trends differ between men and women; not only in B.C. but across Canada,” says Dr. Woods.
“Among men in B.C., the rates of new cases of lung cancer have declined at a steady pace since 1985. Among women, rates were steadily increasing prior to 1992 at which point the increase became more slight. There are now more women diagnosed with lung cancer each year than men in our province.”
The reason for this is due to smoking behaviours among the two groups, given that tobacco use is the most significant risk factor for lung cancer. According to Woods, the proportion of daily smokers in Canada who identify as male peaked in the 1960s, however, among those who identify as female, the proportion only began to decrease in the 1980s. Even decades later, this trend in smoking behaviours is contributing to differences in cancer rates among men and women.
B.C. has five regional health authority areas: Vancouver Coastal, Fraser, Island, Interior and Northern. According to Simkin, there are strong differences in incidence rates across these health authority regions.
Among those who identify as male, rates in the five regional health authorities demonstrate a similar downward trend. When we look more closely, we can see that the decline is slightly stronger in some regions compared to others. While rates in all regions are declining, current rates are highest in Northern and Interior health regions and lowest in Vancouver Coastal. When we look at those who identify as female, we see a very different picture.
“Lung cancer rates have generally increased for women living in all regions in the province except Vancouver Coastal,” says Simkin. “Most notably, rates for women living in the Interior and Northern health regions continue to increase, the North most significantly.”
“We are encouraged to see that overall, lung cancer incidence rates are declining after accounting for population aging and growth. However, even though the rates are declining, an aging and growing population will mean the number of new cases of lung cancer may continue to rise over the next decade,” says Dr. Woods.
“Therefore, it is important for people to reduce their risk through cancer prevention strategies and ensure those with high risk are identified and diagnosed as early as possible.”
Last month, B.C. became the first province in Canada to announce a new lung screening program
for high-risk individuals. While the program is expected to launch in 2022, the BC Lung Screen Trial
is currently available for eligible, high-risk individuals.
“We are thrilled that organized lung cancer screening is coming to B.C. Screening supports early detection and when lung cancer is detected early, our own provincial data suggests outcomes are greatly improved,” adds Simkin.
for more information about lung cancer, including signs and symptoms, and check back for more articles in the lung cancer series which will explore ways to prevent lung cancer and the importance of early detection.