Role of Nuclear Medicine in Lung Cancer

Nuclear medicine is a multifaceted modality that includes various diagnostic and therapeutic applications, with all imaging procedures providing a functional look at the inner workings of organ systems and processes throughout the body. Detecting, staging and monitoring chronic diseases -most prevalent by far being cancer- is a big part of my job as a nuclear medicine and PET technologist. Most cancer diagnoses will lead to at least one nuclear medicine procedure at some point through the staging, planning, treatment or follow-up process, if not several various or repeated tests at specific intervals. The initial ultrasound, x-ray, bloodwork or clinical pattern that raises suspicion of a possible cancer is often promptly followed by a whole-body bone scan. This allows for a thorough evaluation of all the bones in the body to survey for metastases by using one radioactive injection, rather than a series of x-rays or CT scans (both of which would provide a significantly higher radiation burden). The functional, molecular nature of this test also makes it more sensitive, earlier than other, structural-based modalities for small lesions. PET-CT scans using a radioactive glucose analogue demonstrate unparalleled sensitivity to sugar-avid cancerous lesions throughout the body, providing the added benefit of quantitative data that helps predict the usefulness of various therapies. Functional heart imaging is used at regular intervals to monitor cardiotoxic effects of certain chemotherapy drugs. These are just a few of the more general Nuclear Medicine applications relating to cancer. Many others are available for specific cancer indications. I’ll focus my discussion toward lung cancer, due to its link to modifiable behaviors and the fact that it is an indication for which PET imaging is especially useful, and is therefore one that I encounter frequently in my profession.

New Brunswick “has the unwanted distinction of exceeding the Canadian average in smoking rates, adult obesity rates, diabetes, heart and respiratory disease and unhealthy alcohol use” (McGarry, 2016). Also, “Cancer and heart disease are the leading causes of death and premature death in New Brunswick” (Wang, Emrich, & Collette, 2016, p.14). In a list ranking Canadian provinces and territories according to the highest rate of cancer, New Brunswick was found to be second only to Newfoundland (Daley, 2018). Lung cancer is in the top 3 annual cancer diagnoses for both men and women across all provinces and territories, causing the greatest number of cancer related deaths across most -if not all- regions in Canada.

The poor prognosis associated with lung cancer may be attributed to the fact that symptoms rarely appear in the operable stage (Mazières et al., 2015, p.420). Adding to this, lung cancer has the unique perception among the general population as being highly attributable to behavioral choices and thus, those diagnosed tend to suffer greater anxiety as they may feel ashamed of their disease (Mazières et al., 2015, p.420). This stigma contributes to delayed diagnosis, and with that, more advanced disease prior to beginning treatment, which greatly reduces the survival rate. Anecdotally, I regularly have patients tell me that they suffered with a nagging cough for months before seeing their doctor because they were worried what testing might find. Sadly, when this situation results in a lung cancer diagnosis, the punishment is often a painful, mentally taxing struggle that ends with their death.

A major determinant of lung cancer can be summarized as ‘lower socioeconomic state’, as this correlates with multiple factors that increase both incidence and death rates including smoking habits, low education levels, high levels of unemployment, high levels of stress (Wang et al., 2016, pp.9-11), as well as second-hand smoke, air pollutants, radiation and occupational exposures (Alberg, Brock, Ford, Samet, & Spivack, 2013, p.e1S). A statistic from just four years ago states that “only 50 per cent of New Brunswickers aged 16 and older have the literacy skills necessary to function in society” (Wang et al., 2016, p.7). This reduced literacy, leading to a higher rate of unemployment and increased poverty levels -Wang (2016, p.7) places poverty levels among single mothers in the province as high as 45.4%- skews the population toward greater risk of engaging in higher risk health behaviors and occupation exposures, but also neglecting to seek routine healthcare services that may detect lung cancer at a more favorable stage, either by choice, or due to geographical or other constraints.

A physician shortage leaving an estimated 44,000 (from the 770,000 population) New Brunswickers without a family doctor (New Brunswick Medical Society, 2018, p.5) makes early diagnosis -of any issue- an even greater challenge. A shortage of physician specialists means waiting an average of six months (10 weeks longer than the national average!) prior to an initial consultation following referral (New Brunswick Medical Society, 2018, p.8), which extends the time frame for follow up after initially entering the healthcare system. While lung cancer suspicion would result in these patients jumping the queue, the provincial lag compared to the national average is sure to extend its effects to all chronic sufferers.

Resources

Alberg, A. J., Brock, M. V, Ford, J. G., Samet, J. M., & Spivack, S. D. (2013). Epidemiology of lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest, 143(5 Suppl), e1S-e29S. https://doi.org/10.1378/chest.12-2345

Daley, K. (2018). The Canadian Provinces with the Highest Rate of Cancer. Reader’s Digest Best Health. Retrieved from https://www.besthealthmag.ca/best-you/health/the-canadian-provinces-with-the-highest-rate-of-cancer/

Mazières, J., Pujol, J.-L., Kalampalikis, N., Bouvry, D., Quoix, E., Filleron, T., … Milleron, B. (2015). Perception of Lung Cancer among the General Population and Comparison with Other Cancers. Journal of Thoracic Oncology, 10(3), 420–425. https://doi.org/10.1097/JTO.0000000000000433

McGarry, J. (2016). Shifting demographics: Changing the face of healthcare. Retrieved from https://en.horizonnb.ca/home/media-centre/horizon-news/2016-01-08-commentary-john-mcgarry,-president-and-ceo.aspx

New Brunswick Medical Society. (2018). A PLAN FOR HEALTH CARE IN NEW BRUNSWICK: ELECTION 2018. Retrieved from https://www.nbms.nb.ca/assets/Members-Only/Election-2018/Booklet-Web-ENG.pdf

Wang, H., Emrich, T., & Collette, M. (2016). A Report from the Office of the Chief Medical Officer of Health Health Inequities in New Brunswick. Retrieved from www.gnb.ca/publichealth