Can a spinal tumor be misdiagnosed as a case of herniated or compressed discs?

Yes. I had pain, a constant ache in my lower back, and pain in my hip joints that would wake me at night, but would go away when I rolled over. That went on for about 5 years. One AM I woke up, rolled over and stretched, and something snapped so low in my spine, I didn't know anything was movable that far down. And I was pain free for 10 months. Then one AM I woke up unable to move, the pain was so bad. I was literally immobilized for 9 months, I even had to learn to wake up and sit up in order to turn over in bed, before they finally decided there might be something really wrong, and did an MRI. I had a synovial cyst on the inside of my spine, as large as a plum, and it was pressing on nerve roots. They did surgery less than a week later. By that time, there had been so much nerve damage done that it took 7 years for the pain to completely go away, but it was bearable, nonetheless. I was only on pain pills for 2 months after the surgery. Before the surgery, they'd refused to give me anything, and I survived on Naproxin. The synovium is the membrane covering the bones.