Cancer striking younger people, US study finds

A growing number of adults aged 50 and younger are being diagnosed with cancer in the United States and worldwide, prompting concern that there is a silent "global epidemic "brewing.

For decades, cancer was most prevalent in those aged 50 and above. The median age of a person diagnosed with cancer used to be 66, according to the National Cancer Institute.

But doctors are seeing the emergence of cancer among those younger than 50, dubbed "early-onset cancer".

Researchers at Boston's Brigham and Women's Hospital, which is part of Harvard Medical School, found in a study called "Is early-onset cancer an emerging global epidemic?" that approximately 14 cancers had risen significantly in 44 high- and low-income countries.

The study, published in Nature Reviews Clinical Oncology in September, found that several types of cancer, including breast, gallbladder, kidney, liver, stomach and thyroid, have increased in those aged 50 and younger.

The researchers found that many of the cancers that had become more prevalent lately affect the gut.

Shuji Ogino, a co-author of the study and pathology professor at the Harvard T.H. Chan School of Public Health, said several risk factors are contributing to more people being diagnosed with early-onset cancer. These include obesity, alcohol, smoking, environmental pollution and Western diets high in meat and sugar.

Ogino believes doctors are able to pinpoint if a person has cancer more readily because of increased screening. And while comparing data from the 1990s until now, he noticed that the risk of cancer was increasing with each generation.

Higher risk

"From our data, we observed something called the birth cohort effect. This effect shows that each successive group of people born at a later time — e.g., a decade later — have a higher risk of developing cancer later in life, likely due to risk factors they were exposed to at a young age," Ogino wrote in the report.

"We found that this risk is increasing with each generation. For instance, people born in 1960 experienced higher cancer risk before they turn 50 than people born in 1950, and we predict that this risk level will continue to climb in successive generations."

The American Cancer Society estimated that more than 600,000 people in the US will die from cancer this year.

Jun J Mao, chief of integrative medicine service at Memorial Sloan Kettering Cancer Center in New York, said for those with cancer seeking pain relief, taking a holistic approach and combining Western and Eastern healthcare can help.