Since cancers arise in a wide variety of sites and develop with many differing patterns of spread, there are no definite symptoms. The exact nature of symptoms depends not only on the location of the primary tumor but particularly on where the tumor is located - in or near an organ, its rate of development and probability of metastastic spread of the cancerous cells to other sites in the body.

Many primary tumors cause local swelling or lump if they arise at a visible or accessible part of the body, such as skin, breast, oral testicle or cavity. A typical swelling due to a cancer is initially painless, though ulceration (skin breakdown) can occur, which may then become painful. Any persistent cough, change in voice, difficulty in swallowing, change in normal bowel habits, abnormal bleeding and non healing ulcer should signal a high index and suspicious for further investigation.