What does lower thoracic myelopathy mean? possibly a tumor? thanks

Term: myelopathy is medical term for lesion of the spinal cord. I suppose the question is, what lesion? Tumor (as you have asked), Demyelinating disorder, MS, etc. MRI and medical evaluation can help sort this out.

Spinal cord disease: Lower part of spinal cord is affected here but the causes can be varied, ranging from tumor of the spinal cord to cord compression caused by trauma or spinal bone mets, to traumatic injury of the spine affecting the spinal cord.

Cord abnormality: The term myelopathy refers to the signs and symptoms that can occur from abnormalities of the spinal cord. The spinal cord runs from the base of the brain down to approximately the L1-L2 level. The term lower thoracic would be in the lower part of your "mid-back". Patients with myelopathy can have numbness, loss in coordination, weakness, and even loss of control of the bowel and bladder.