My wife was actually diagnosed with Polycythemia Vera in 1978. Back then it wasn’t known as a “cancer” just a blood disorder. Blood letting was the only treatment. When she became pregnant in 1986, she was a-symptomatic from then until 2017 when a routine blood test showed “blasts” as well as abnormal platelets and red cells. Currently her only symptoms are itchy skin, fatigue, spleanomeglia, and heat intolerance with hot spells.
My point is this disease can go undetected for decades. She is now in a “Milyofibrocis stage.