Predicting Global Cancer Trends in 2021
A Conversation With Don S. Dizon, MD, FACP, FASCO
Although we are just halfway through 2021, the outlook for improvements in global cancer trends looks grim. According to new estimates by the International Agency for Research on Cancer’s Global Cancer Observatory, the global cancer burden rose to 19.3 million cases and 10 million deaths in 2020 and is predicted to increase to more than 30 million cases and over 16 million deaths by 2040, with most of the increases occurring in low- and middle-income countries.1
Breast cancer remains the most common cancer among women globally, followed by colorectal, lung, cervical, and thyroid cancers. Lung and prostate cancers are the most common among men, accounting for nearly one-third of all cancers diagnosed in men, followed by colorectal, stomach, and liver cancers.1
“Without the epidemiologic data from population-based registries, the ability to accurately assess the cancer burden and allocate appropriate resources is limited.”— Don S. Dizon, MD, FACP, FASCO
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Aging populations; limited access to preventive and oncology care services; late-stage presentation of disease; a shortage of cancer specialists, medicines, and diagnostic equipment; obesity; and lifestyle choices (including smoking and alcohol use) are all fueling the increase in cancer incidence and mortality around the world. To help blunt the global cancer epidemic and improve survival rates for underserved patients, the Global Cancer Institute (GCI; https://globalcancerinstitute.org/global-cancer-institute/) has initiated programs to reduce barriers to cancer control. They include the Young Women’s Global Breast Cancer Database, which collects lifestyle and clinical information on young patients to improve patient outcomes and quality of life; a patient navigation program to assist patients with finding physicians and booking treatment appointments; Improving Clinical Care and Expertise; and global tumor boards, fellowships, and scholarships, which help physicians in low-resource countries reach a consensus on the care of patients with complex cancers and improve the standard of cancer care globally.
The ASCO Post talked with Don S. Dizon, MD, FACP, FASCO, about how to improve global oncology care, especially for underserved patients; the importance of establishing a universal cancer registry; and trends in cancer incidence and mortality in the coming year. Dr. Dizon is Co-Chief Medical Officer of the Global Cancer Institute, Professor of Medicine at the Warren Alpert Medical School of Brown University, and Director of Women’s Cancers at Lifespan Cancer Institute at Rhode Island Hospital.
Bringing High-Quality Cancer Care to Low-Resource Settings
Please talk about the work you are doing with the Global Cancer Institute to improve access to cancer care, especially in low- and middle-income countries.
This past October, Founder and Chief Mission Officer of the Global Cancer Institute, Paul E. Goss, MD, PhD, FRCPC, FRCP (UK), stepped down as Chief Mission Officer and appointed me Chief Medical Officer of the gynecologic program and Ben Ho Park, MD, PhD, as Chief Medical Officer of the breast program. Our goals are to learn more about cancer incidence, mortality, and care delivery, not just from the perspective of high-income countries, but from the perspective of low- and middle-income countries as well. We are doing this through the three core pillars of GCI’s mission: researching barriers to cancer control, enhancing access to cancer care, and improving clinical care and expertise for patients in resource-limited settings.
Our mission is built on the foundation Dr. Goss established when he was Director of Breast Cancer Research at Massachusetts General Hospital Cancer Center. Dr. Goss sponsored investigators and clinicians from low- and middle-income countries to participate in clinical trials in early breast cancer treatment and breast cancer prevention, so when they returned to their home countries, they could execute similar programs.
In our program at GCI to improve clinical care and expertise, Dr. Park and I are convening experts in the United States to provide video-based global tumor boards in breast and gynecologic cancers to provide consultation and advice on difficult cancer cases. These tumor boards meet monthly, and the participants are able to ask questions about clinical trials that are underway in our country as well as the data we use to determine treatment for these cancers.
For example, recently, we were able to assist a physician in Nepal who was treating a patient with early-stage NTRK gene–fusion positive breast cancer in gaining access to the TRK inhibitor entrectinib, a drug approved by the U.S. Food and Drug Administration (FDA) in 2019 to treat patients with solid tumors harboring a specific genetic alteration.2 We even offered to consult on the pathology reports of patients with complicated breast and gynecologic cancers. So, it is that level of expertise we are able to offer colleagues in low-resource countries.
We also provide fellowships and scholarships to young doctors for training in the United States to better prepare them to serve patients in their local communities. These GCI fellows remain connected to the Institute and continue to collaborate on our projects. One such project is the Young Women’s Global Breast Cancer Database, which helps improve care for patients in their home countries but also improves our global understanding of breast cancer incidence and mortality in young adults.
Developing a Global Population-Based Cancer Registry
GLOBOCAN 2020 is predicting that countries classified by the United Nations as having a low or medium human development index will experience the greatest relative increases in cancer incidence and mortality by 2040.1 Part of the difficulty of accurately measuring the full extent of the cancer burden in low-resource countries is the inability to capture reliable national cancer data within these countries. Is progress being made to develop a worldwide population-based cancer registry to inform better cancer control in these regions?
It remains a very difficult endeavor. The International Agency for Research on Cancer has launched a Global Initiative for Cancer Registry Development (https://gicr.iarc.fr), but progress is slow. Part of the difficulty is that each country has its own political and financial priorities. And some countries, such as Ethiopia, are in the midst of civil war, so cancer-specific issues may not be a priority of those societies at this time.
“I’m interested to see what will happen to the worldwide incidence of cervical cancer once more countries vaccinate their citizens.”— Don S. Dizon, MD, FACP, FASCO
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Low- and middle-income countries have the least cancer registry data. Without the epidemiologic data from population-based registries, the ability to accurately assess the cancer burden in these countries and allocate appropriate resources is limited. More than being able to predict cancer incidence and mortality, having such a registry would allow us to understand what proportion of patients with colorectal cancer, for example, underwent a colectomy or had access to chemotherapy, or what proportion of patients with breast cancer had access to monoclonal metabolite therapy, which has improved survival outcome for patients. Not having a global cancer registry makes it difficult to analyze trends in survivorship.
Complicating the development of such a registry now is the global COVID-19 pandemic, which has taken precedence over cancer control. Also, there is the question of which international agency would coordinate and control such an effort. I think the honest broker to be the caretaker of a global cancer registry would be a governing body like the World Health Organization (WHO), which has an interest in the cancer space. WHO’s leadership during the COVID-19 pandemic proves the organization has the capacity to develop and maintain a reliable global cancer registry, but I don’t know if this is something WHO wants to take on.
Reducing Incidence and Death From HPV-Related Cancers
What are some of the top global cancer trends you are seeing in 2021?
One of the major trends I’m watching is the role the human papillomavirus (HPV) vaccine will have on curbing the development of HPV-related gynecologic cancers as low- and middle-income countries adopt and execute HPV vaccination programs. I’m interested to see what will happen to the worldwide incidence of cervical cancer once more countries vaccinate their citizens, including the United States.
In 2018, the WHO estimated that 570,000 women were diagnosed with cervical cancer worldwide, and about 311,000 women died of the cancer.3 I’m hoping to see these figures trend downward as more people are vaccinated and to start to see a disappearance of cervical cancer incidence and other HPV-related cancers over the coming decades.
Unfortunately, I think we will start to see a reversal of the decline in cancer deaths we have seen in the United States and in other high-income countries, where screening programs and cancer monitoring are established, because the COVID pandemic has caused screening delays. As a result, there will be more advanced cancers diagnosed this year and more cancer deaths in high-income countries, and I worry about that.
Reducing Cancer Mortality
According to the GLOBOCAN Cancer Tomorrow prediction tool, breast cancer worldwide is expected to increase by more than 46% by 2040.4 A relatively recent study investigating the global trends in premenopausal and postmenopausal breast cancer incidence found that higher-income countries are seeing higher rates of premenopausal breast cancer, whereas lower-income countries are seeing rising cases of postmenopausal breast cancer.4 Do you know why there is this discrepancy in pre- and postmenopausal breast cancers between high- and low-income countries?
This is a fascinating question, and I wish I had a good answer. The study by Heer et al you referenced suggests that the adoption of a more Western lifestyle, such as less physical activity, higher alcohol consumption, use of hormone replacement therapy, and screening programs for breast cancer, in low-resource countries may be contributing factors to the rise in postmenopausal breast cancer. However, it is also important to discern what role hormones play or whether there is an interplay between biology and the environment in these countries.
In high-income countries, the study suggests that deciding to have few or no children, putting off childbirth to an older age, and earlier screening may explain the uptick in premenopausal breast cancer.
What comes up often in our global breast cancer tumor board videoconferences is how limited access to genetic—and genomic—testing is in low- and middle-income countries. If we could identify families at risk for developing breast cancer, that would be an opportunity to control the incidence of breast cancer in subsequent generations. Improving access to genetic screening is an imperative we need to push on a global level.
We also need to make drugs that have a proven survival advantage available in low-resource countries, including trastuzumab and tucatinib, a small-molecule inhibitor of HER2 that was recently approved by the FDA. So much of the survival disparity we see in developing countries is due to a lack of early screening and early diagnosis capability, but lack of access to more targeted drugs is also contributing to higher death rates for all cancers.
In 2019, the WHO added 12 new oncology therapeutics to its Essential Medicines List, including 5 therapies to improve survival outcomes in lung and prostate cancers, melanoma, multiple myeloma, and leukemia, and that was great news.5 However, the list needs to be a living, dynamic document that continues to grow.
We need all of the voices in the global cancer community to demand better access to preventive care, screening, and life-saving cancer therapies for patients—no matter where they live— to reduce cancer incidence and improve survival outcomes worldwide.
DISCLOSURE: Dr. Dizon holds stock or other ownership interests in InfiniteMD and NeuHope; has served as a consultant or advisor to AstraZeneca, Clovis Oncology, i-Mab, Regeneron, and Tesaro; and has received institutional research funding from Bristol Myers Squibb, Kazia Pharmaceuticals, Merck Sharp & Dohme, Pfizer, and Tesaro.
1. UICC: GLOBOCAN 2020: New global cancer data. December 17, 2020. Available at www.uicc.org/news/globocan-2020-new-global-cancer-data. Accessed June 16, 2021.
2. National Cancer Institute: FDA approves entrectinib based on tumor genetics rather than cancer type. Available at www.cancer.gov/news-events/cancer-currents-blog/2019/fda-entrectinib-ntrk-fusion. Accessed June 16, 2021.
3. World Health Organization: Cervical cancer overview. Available at www.who.int/health-topics/cervical-cancer#tab=tab_1. Accessed June 16, 2021.
4. Heer E, Harper A, Escandor N, et al: Global burden and trends in premenopausal and postmenopausal breast cancer: A population-based study. Lancet Glob Health 8:e1027-e1037, 2020.
5. World Health Organization: WHO updates global guidance on medicines and diagnostic tests to address health challenges, prioritize highly effective therapeutics, and improve affordable access. July 9, 2019. Available at www.who.int/news/item/09-07-2019-who-updates-global-guidance-on-medicines-and-diagnostic-tests-to-address-health-challenges-prioritize-highly-effective-therapeutics-and-improve-affordable-access. Accessed June 16, 2021.