47–year–old male with past medical history of chronic back pain presented to emergency room complaining of exacerbation of symptoms. Patient reported three months history of sharp excruciating pain that was located on the right lower back radiating down both legs. Patient reported trial of numerous opoid analgesics without resolution of pain. There were no associated issues with bowel or bladder incontinence. On admission vitals were stable and on physical exam patient demonstrated hesitation with gait but no other abnormalities were noted. X–ray of the lumbar spine showed bilateral widening of the sacroiliac joints. An MRI was scheduled on outpatient basis which demonstrated a large neoplasm involving S1 and S2 with soft tissue extension anteriorly into the prevertebral soft tissues (Image 1). A CT guided biopsy was performed which showed presence of multi–nucleated giant cells and a diagnosis of giant cell tumor was established (Image 2). Patient was referred to a specialty center to attempt tumor resection. Initial treatment with radiation was initiated and then neurosurgical team performed a 12–h long procedure to successfully remove the tumor. Patient had a subsequent follow–up at our outpatient center and remains pain free since the surgery.
Back pain is one the most common reasons for outpatient doctor visits in United States. According to some estimates 27 million Americans have reported back problems. Due to the abundance of patients complaining of back pain there are often instances when an underlying malignancy can be missed. In this case, patient was found to have giant cell tumor (GCT) of the bone. This type of tumor is rare and comprises of less than 5% of the primary bone tumors. Pain is the most common presenting symptom. GCTs are mostly found in the distal femur, proximal tibia and distal radius. In our case the tumor was invading the sacral spine and causing pain by producing mass effect.
Giant cell tumor of the bone is a rare entity but it may present just like any other back pain.
Image 1MRI Image showing neoplasm.
Image 2Pathology slide showing multi–nucleated giant cells.