Analysis by Macmillan Cancer Support shows there were 361,216 cancers diagnosed in 2014 in the UK, compared with 289,841 marriages.
New cancer cases are also as common as graduating from university, and more common than a woman having her first baby.
There were 271,050 babies born to first-time mothers in England and Wales in 2015, compared with 319,011 new cases of cancer.
The data also showed that, over the last decade, more than 1.2 million people have been diagnosed with cancer under the age of 65.
This includes 343,000 people in the UK who were diagnosed with cancer in their 20s, 30s or 40s between 2006 and 2015.
Research among more than 2,000 people for the charity also showed that cancer is the disease people fear the most (37%), ahead of Alzheimer’s disease (27%), stroke (7%), depression (4%), heart disease (4%) or multiple sclerosis (2%).
And for one in 10 people in the UK (10%), cancer is their biggest fear of all, ahead of losing a loved one, their own death or terrorism.
Projections suggest that around half of people will develop cancer at some point in their lives.
However, 90% of people living with cancer surveyed by Macmillan said they were still living their lives as normally as they could.
Lynda Thomas, chief executive of Macmillan Cancer Support, said: “Being told you have cancer changes your life, and it can leave people feeling as if they’ve been thrust into the unknown, bewildered and unprepared.