IWH study estimates costs of non-melanoma skin cancers due to sun exposure at work

Figure of $34.6M for cancers diagnosed in one year is the first estimate in Canada of the economic burden of work-related cases of two common forms of skin cancer

Published: April 26, 2018

In 2011, just over five per cent of the newly diagnosed cases of basal cell carcinoma (2,846 of 53,696) in Canada were due to sun exposure at work. Just over nine per cent of the newly diagnosed cases of squamous cell carcinoma (1,710 of 18,549) were attributed to work-related sun exposure.

That’s according to a recent study by the Institute for Work & Health (IWH), which put the cost of each case of work-related basal cell carcinoma at $5,670 and of work-related squamous cell carcinoma at $10,555.

The societal costs of these new cases from 2011 add up to $28.9 million in direct and indirect costs. Direct costs include health-care treatment and related expenses, and indirect costs include production losses. When intangible costs (such as the monetary equivalent of loss of quality of life) are included, the total social costs increase by another $5.7 million, to $34.6 million.

The study by IWH Senior Scientist Dr. Emile Tompa and visiting researcher Amir Mofidi was recently published in the Journal of Occupational and Environmental Health. The open-access article is available free of charge.

The study is the first ever analysis of the economic burden of work-related basal cell carcinoma and squamous cell carcinoma—which together are known as non-melanoma skin cancers.

These cancers are far more prevalent than melanoma, and basal cell carcinoma specifically is the most common form of any skin malignancy. Skin cancers are the most common form of cancer in Canada, accounting for a third of all cancers in the country.

According to previous research conducted by CAREX Canada, over 1.5 million Canadian workers are exposed to solar ultraviolet radiation (UV) on the job. About 900,000 of these individuals spend more than 75 per cent of their work days outdoors. (A high level of exposure to solar UV is defined as spending six hours or more outdoors per work day.)

Among the sectors in this high-risk category are construction (including road work), agriculture, and transportation and warehousing. The occupational groups in Canada with the highest levels of sun exposure are farmers and farm managers, construction trades helpers, and landscaping and ground maintenance labourers.

Three categories of costs

To calculate the economic burden of these occupational cancers, the study team first estimated the incidence of newly diagnosed non-melanoma skin cancers in 2011 attributed to work-related sun exposure. The attribution work was carried out by two members of the research team prior to this project.

The researchers then estimated the lifetime costs of these cancers using a method they had previously used to estimate the economic burden of lung cancers and mesotheliomas due to work-related asbestos exposure.

The team included in its estimates three broad categories of costs:

  • direct costs – health-care costs related to diagnosis, treatment and follow-up; out-of-pocket costs related to travel for seeking care, prescription drugs, homemaking services needed due to incapacity, vitamins and supplements, and more; and informal caregiving costs provided by family members;
  • indirect costs – productivity losses, including the costs associated with lost days of work due to seeking treatment, illness and death; and costs associated with lost production at home; and
  • intangible costs – pain, suffering and loss of enjoyment of life; and loss of engagement in social roles, including family, community, leisure and work roles.

The $34.6 million in total costs is made up of roughly 58.5 per cent direct costs, 25 per cent indirect costs, and 16.5 per cent intangible costs.

High survival rates

Because non-melanoma skin cancers tend to be caught early and treated efficiently, the economic burden of these cancers is predominantly from direct, treatment-related costs. Generally, treatment requires very little time off work for most cases, and the long-term consequences are few if caught early, says Tompa. The survival rate is 99.98 per cent for basal cell carcinoma and 99.30 per cent for squamous cell carcinoma.

The researchers also used the same approach to estimate the cost of newly diagnosed occupational non-melanoma skin cancers due to sun exposure in 2011 in the United States. They calculated the cost to be $1.7 billion (in Canadian dollars). They noted, however, that this may be an under-estimation, as health-care costs are likely higher in the U.S., and cancers due to sun exposure are likely more prevalent in the more southern latitudes of the country.

We hope the availability of these estimates helps policy-makers, employers, unions and workers consider the impact of work-related sun exposure, says Tompa. Knowing the economic burden of these two cancers may be useful, especially when the workplace interventions to reduce exposure to the sun—for example, shade structures, tinted windows on vehicles, shift schedules that avoid time spent in the midday sun, clothing and hats or sunscreen—tend not to be very expensive.