For example, the Ontario Human Rights Code prohibits discrimination because of disability, and defines “disability” to mean:

(a) any degree of physical disability, infirmity, malformation or disfigurement that is caused by bodily injury, birth defect or illness and, without limiting the generality of the foregoing, includes diabetes mellitus, epilepsy, a brain injury, any degree of paralysis, amputation, lack of physical coordination, blindness or visual impediment, deafness or hearing impediment, muteness or speech impediment, or physical reliance on a guide dog or other animal or on a wheelchair or other remedial appliance or device,

(b) a condition of mental impairment or a developmental disability,

(c) a learning disability, or a dysfunction in one or more of the processes involved in understanding or using symbols or spoken language,

(d) a mental disorder, or

(e) an injury or disability for which benefits were claimed or received under the Workplace Safety and Insurance Act.

For federally regulated employers, the Canadian Human Rights Act defines “disability” to mean “any previous or existing mental or physical disability and includes disfigurement and previous or existing dependence on alcohol or a drug.”

Thus, such things as cancer and multiple sclerosis would be considered valid disabilities that need to be accommodated under human rights legislation to the point of undue hardship. However, the type of accommodation must be individualized and meet the needs of the disabled employee in question.

I hope this helps.