What happened, in summary

A 42-year-old woman developed progressive weakness in both legs over 3 weeks. The weakness advanced to paraplegia and was accompanied by mid-back pain, numbness, and loss of bowel and bladder control. Examination showed very limited leg movement, reduced reflexes, and a sensory level around the lower chest. During the same assessment, clinicians found a 3 x 2 cm mass in her right breast with thickened overlying skin.

Emergency MRI showed a 30 x 8 mm tumor inside the spinal cord at the D11-D12 level. The mass enlarged the cord and enhanced strongly with contrast. Brain MRI and cerebrospinal-fluid testing did not show another cause for her neurological symptoms.

Biopsy of the breast mass showed grade II invasive carcinoma of no special type. The cancer was estrogen receptor-positive, progesterone receptor-negative, and HER2-negative with a score of 0. PET imaging showed active disease in the right breast, the spinal-cord lesion, several axillary lymph nodes, and both adrenal glands. These findings established metastatic breast cancer presenting through an intramedullary spinal-cord metastasis.

She was started on dexamethasone to reduce swelling and received local external-beam radiation to the spinal lesion. Her leg strength and bowel and bladder function did not recover after treatment. The cancer progressed rapidly despite the local therapy. She died 3 months after the breast-cancer diagnosis.

The spinal lesion was the first sign that brought the previously undiagnosed breast cancer to attention. Brain imaging was normal, but the neurological injury was already severe when treatment began.