Only you, a person with a sound mind, can feel symptoms of a health problem in its earliest stage.
Only you, a person with a sound mind, can detect a health problem in its earliest stage short of a screening diagnostic tests.
The most practical way of detecting health problem in its earliest stage is still to do a self-examination, NOT screening diagnostic procedures.
Aside from trying to feel for any symptoms that may suggest a health problem, do a self-palpation of your entire body on a regular basis to look for signs of any health problem that may be present. Particularly, palpate your own body to look for any unusual lump, growth, or mass that may turn out to be a cancer.
A lump is one of the most common presentation of a disease in a person. A lump may be a cancer or not a cancer.
The goal is to detect a lumpy that may be a cancer as early as possible and then have it treated right away. Early diagnosis and treatment of a lump that turns out to be a cancer carries the best chance for cure and survival.
Make it a regular habit to palpate your own body, particularly in areas that are commonly affected by cancers and that can easily be detected by your naked eyes and your palpating fingers such as the skin and soft tissues, breasts, and head and neck.
Look for a dominant mass which is usually an abnormal mass and which is a red flag that needs to be investigated further. See illustrations below.