3 Cancers on the Rise and What You Should Know to Protect Yourself
While the news on the cancer front is generally encouraging, there are a few cancers that are increasing — particularly among younger Canadians.
“There’s been a dramatic increase in thyroid cancer rates,” says Dr. Smith. Between 1970 and 2017, thyroid cancer rates of incidence increased in women from 3.9 to 23.4 per 100, 000 and in men from 1.5 to 7.2 per 100 000 while mortality rates have remained stable at around 0.5 per 100, 000 for both sexes, according to a 2017 study in The Canadian Medical Association Journal. The biggest surge was seen in women aged 40 – 60 years, though it is the most commonly diagnosed cancer in people aged 15 – 29.
Dr. Sam Wiseman, associate professor in the Department of Surgery at the University of British Columbia, attending surgeon St. Paul’s Hospital and director of research in the Department of Surgery at Providence Health Care in Vancouver, says the surge in diagnoses are believed to be related to more incidental pickups caused by an increase in imaging and the availability and utilization of neck ultrasounds. Dietary and environmental factors aren’t out of the question either. Exposure to radiation, certain genetic conditions, a family history of thyroid cancer, obesity, certain benign thyroid conditions and being tall are all risk factors.
Methods used for detection
He says that with the use of sophisticated and commonly-used imaging, such as CT, MRI and PET scans, the nodules are found during scans for other health investigations — as in Kruse’s case. “There’s increased detection of these cancers — many of which, though not all, would have remained clinically insignificant in a person’s life.”
Dr. Wiseman says that most nodules (95 percent) are benign and even if cancer is diagnosed — be it papillary carcinoma or follicular carcinoma — survival rates are high. “The vast majority of thyroid cancers have an excellent prognosis.” He says that more lethal forms do exist but are rare. These include poorly differentiated carcinoma, anaplastic carcinoma, and medullary carcinoma.
According to Dr. Wiseman, aggressive treatment is now weighed more carefully than in the past. If a nodule is found that’s less than a centimeter in size, active surveillance is recommended. “Follow-up with ultrasound is an option for those people,” he says. For cancers, patients generally need a portion, or all of, their thyroid gland removed — and may also need additional treatment with radioactive iodine. “It hinges upon the characteristics of the patient’s tumour,” he says.
The best news is that despite the steady increase in diagnoses, “overall mortality has remained unchanged,” says Dr. Wiseman. Net survival for thyroid cancer at five years is 98 percent, according to the Canadian Cancer Society. And survival rates are higher for those diagnosed under age 40.
Regardless, if someone finds a lump or swelling in the neck, notices hoarseness or other voice changes, has difficulty swallowing or breathing, experiences a sore throat or cough that doesn’t go away, or has a persistent pain in the front of the neck, they should see their doctor.
First the good news: “Colon cancer is very rare under the age of 50,” says Dr. Prithwish De, director of Surveillance and Cancer Registry, Cancer Care Ontario (CCO).
That said, when CCO researchers looked at national data on colorectal cancer from the mid 1990s until 2010, they discovered that the biggest increases were among those aged 15 – 29. “There was about a seven percent increase per year (in incidence) from the mid 1990s to 2010,” says Dr. De. Perplexed, the researchers looked at other trends in this demographic. “A seven percent increase is quite large, says Dr. De. “We tried to explain that looking at the lifestyle risk factors.”
However, Dr. De says that most risk factors for colon cancer — inactivity, a diet high in red meat and little fibre, smoking and drinking — were not suspected as drivers of the spike in these colon cancer cases, since there hadn’t been a notable increase in the prevalence of these risks for that age group. “Food and vegetable intake has been going up, people have become more physically active, alcohol intake hasn’t changed much and smoking has been decreasing in all age groups,” says Dr. De. Instead, the team focused on body mass. “The one that stood out in terms of significant increases was obesity,” he says.
Dr. De says scientists are now looking at how diet and body weight affect the development of colon cancer.
Symptoms to watch for
In the meantime, he suggests minimizing the risk of colon cancer, and monitoring symptoms such as a change in bowel habits, blood in stool, abdominal pain, excessive gassiness, or narrower stool. He also suggests younger patients with these symptoms take action. “Doctors don’t tend to consider cancer among young people very often,” he says. “They should be more vigilant.”
Uterine cancer diagnoses are on the rise. It was the most commonly diagnosed reproductive system cancer in 2010, with a rate of 30.3 new cases per 100 000 women, according to Statistics Canada. That incidence represented the highest rate of uterine cancer since 1992.
There are two main types of uterine cancer. Endometrial carcinoma, which starts from cells in the lining of the uterus (called the endometrium), is the most common form of this cancer. There are also uterine sarcoma, which develops in the supporting tissues of the uterus, and carcinosarcoma, which sometimes develops in the uterus.
What’s driving the increase in diagnoses? Dr. Lilian Gien, a gynecologic oncologist at the Odette Cancer Centre, Sunnybrook Health Sciences Centre, says that obesity may play a part. “There’s an increase in the rate of obesity.” When you have a lot of extra body fat, that extra estrogen can change the lining of the uterus, she says.
It’s for that reason that most cases of uterine cancer are diagnosed in women who are in menopause. The median age group of patients with endometrial carcinoma is 61 years with 75 – 80 percent being post-menopausal. Only 3 – 5 percent of women who develop it are under 40.
Risk factors include:
Having Lynch Syndrome, a genetic condition that also increases the risk of colorectal and stomach cancers, being overweight, having abnormal periods and being diabetic, says Dr. Gien.
She says having irregular periods means that the lining of the uterus is not shedding each month. If this occurs, taking low-dose contraceptives can make you have more regular periods and reduce the risk of developing endometrial cancer. A hormone-releasing IUD can also help thin the lining of the uterus and prevent it from turning into cancer, she says. For women who do develop uterine cancer, survival rates are high: 84 percent of those diagnosed will survive for at least five years.
“Don’t think that there’s nothing you can do about it,” says Dr. Gien.