I feel fullness(pressure)in upper abdomen or slightly left upper abdomen. But there is no pain. Follow a normal diet and stool looks normal. But for somedays I have been feeling fullness in the upper abdomen and slight upper back pain. This fullness comes and goes away. Except for the above mentioned symptoms I dont have any other symptoms. Can this be a symptom of any tumor or cancer. Any blood test or tests that can be recommended to diagnose the cause.