I'm super happy to hear that you probably caught this in time, CW. But the above sentence is something that is way too common for men and we need to change it. Medical science is the main reason we live longer and healthier lives, but it doesn't help unless we use it. Do yearly checkups, get your blood tested, get all the preventative and diagnostic tests you can. Catching stuff early is key.
I also had cancer. I'll tell my story, so you're not alone here. Like you, I rarely went to the doctor, but I was having pain in my back and sides. My doctor minimized it - told me to do more exercise. I worked on my flexibility and strength and came back a few months later. I told my doctor I could deadlift 250 lbs and showed him that I could touch my toes with ease: my strength and flexibility were fine. He again minimized it, telling me that I have a desk job and I should do yoga.
I went back the next day and demanded to see a different doctor. This is in Canada, so it's not easy to just 'see a family physician'. But I was adamant, almost making a scene but careful not to get kicked out. They let me see someone else... long story short, I had stage 4 lymphoma, a large tumour near my spleen that was giving me pain, another tumour near my heart, cancer throughout the lymphatic system, and in my bones. If they had caught it when I first went to the doctor, it probably would have been stage 2.
It was an extremely aggressive and fast spreading cancer. Ironically, that makes it easier for chemo to kill it (since chemo targets actively growing cells). My oncologist told me that I would either be dead in 6 months or they would be able to get it all. That was 9 years ago, so I'm in the clear.
Bottom line: don't take your health for granted, don't ignore pain, go to the doctor for yearly check ups, don't be satisfied with the bare minimum of testing.