A 53-year-old Caucasian female with ESS was referred to our neurosurgery outpatient clinic in March 2010 after a routine position resonance imaging (PET) scan 2 months earlier revealed increased uptake in the L3 spinous process (). Magnetic resonance imaging (MRI) of the lumbar spine in March 2010 revealed a 3-centimeter heterogeneously enhancing mass involving the lamina, spinous process, right pedicle, and right transverse process of L3, with expansion into the paraspinous muscles and without involvement of the dorsal fascia or epidural space ().
PET/computed tomography showing increased uptake and erosion of the spinous process in the dorsal L3 region.
Preoperative lumbar MRI images. (A) Sagittal T1 with gadolinium, (B) Axial T1 with gadolinium.
The patient initially presented to her primary care physician 3 years earlier with symptoms of urinary incontinence, and a workup revealed uterine fibroids. She underwent supracervical hysterectomy. The pathology report identified multiple leiomyomas within the myometrium, some with myxoid change. One year later, the patient developed worsening urinary incontinence. She was found to have a large pelvic mass. Core biopsy showed a myxoid spindle cell lesion with reactivity against desmin and weak reactivity against muscle-specific actin. Immunohisto chemistry against CD10 was non reactive. The features were interpreted as suggestive of leiomyosarcoma. Biopsies of additional intra-abdominal lesions were morphologically similar, but these tumors failed to react against muscle-specific actin, smooth muscle actin and CD10. Therefore, a diagnosis of primary ESS was favored.
The patient underwent preoperative radiation therapy followed by extensive resection of the intraabdominal tumor. Discovery of metastatic disease led to an end colostomy and palliative chemotherapy with taxotere and ifos/Adria. Because of intolerable side effects (including leukocytosis, alopecia, skin changes, fatigue, and nausea) and local progression of disease, she was switched to hormonal therapy with megace, then an aromatase inhibitor. Her disease was stable for year on hormonal therapy, and then the patient underwent pelvic exenteration (hemicolectomy in October 2008; cystectomy, proctectomy, and partial vaginectomy in July 2009). Evaluation of the resected colon, urinary bladder and vagina again showed a spindle cell tumor morphologically similar to that seen in the patient's previous biopsies and resection, but also small areas of high-grade sarcoma. This specimen showed reactivity with anti-CD10 antibody and no reactivity against desmin, actin, myoD, or S100 protein. The findings were interpreted as consistent with ESS, predominately low-grade, with focal areas with high-grade features.
The patient's paraspinal mass was unusually aggressive. Two months after pelvic exenteration surgery, the patient reported hip flexion and abduction weakness. Diagnostic considerations included chemotherapy-induced neuropathy, radiation-induced lumbosacral plexopathy, and iatrogenic femoral nerve injury. Her obturator nerve was resected during the surgery. Electromyogram showed right obturator neuropathy, which was believed to explain her right hip flexion and abduction weakness.
At the time of the routine PET scan that revealed the lumbar mass (January 2010), she had no back pain. One month later, she developed dull aching lower back pain, with occasional stabbing on the right, and paresthesias bilaterally to the feet. Physical examination revealed no neurologic deficits and no palpable mass in the lumbar region. An MRI of the cervical and thoracic spine showed a small, rounded, hypointensity of the C4 vertebral body but was otherwise normal. A bone scan showed suspected metastases in the bilateral femoral diaphyses, left humeral head, right seventh rib, and mid-lumbar spine. The original PET scan from January 2010 also showed mild enlargement of a right middle lobe lung mass and other bony metastases.
Despite the presence of other bony and soft-tissue metastases, we decided to decompress the lumbar mass because of the patient's good performance status, intolerance to chemotherapy, the large size of the lesion that correlated with the imaging and limited her daily activities, and the expectation of a minimally morbid surgery given the predominantly dorsal location of the lesion. The goals of surgery were to improve her hip and back pain and debulk the tumor to facilitate adjuvant treatment.
Intraoperatively, the tumor protruded through the lumbar fascia. A clear plane was evident between the tumor and paraspinous muscles in some areas, but roughly 60% of the tumor was blended with the surrounding muscle and the L3 spinous process was partially eroded. After L3 laminectomy, we found significant epidural tumor extension with adherence to the dura. Epidural tumor in the central canal was resected, but tumor remained in the lateral recess traveling out the neural foramen on the right at L2–3 and in the right L3 pedicle (). Based on preoperative imaging and the patient's known multiple metastases, we had not planned for gross total resection. We did not perform fusion and stabilization because the procedure is associated with a higher complication rate, and longer recovery time, and felt that it would not affect overall survival. Further, because of her planned radiation therapy, she had a higher risk of non union. Total volume of resected tumor submitted to pathology was 181.2 cm3 compared with preoperative volume estimated by MRI to be 27 cm3. This change represented a 5.7-fold increase in total tumor volume over a 6-week period. The pathology report identified a malignant myxoid spindle cell lesion with predominately low-grade features and focal high-grade morphology which was consistent with origin from the patient's previously diagnosed sarcoma (). The patient then received palliative radiation to the lumbar paraspinal region. She was offered systemic chemotherapy, but refused because of her previous experience with the chemotherapy-related side effects.
Postoperative lumbar MRI images. (A) Sagittal T1 with gadolinium. (B) Axial T1 with gadolinium.
During workup for a persistent headache 1 month later, MRI of the head revealed an avidly enhancing expansile mass in the body of the sphenoid bone, with soft tissue extension into the sphenoid sinus and posterior ethmoid air cells. Abnormal marrow replacement surrounded the area in the lesser wing of the sphenoid bone and clivus (). A stereotactic-assisted transsphenoidal biopsy was performed without complication. The lesion was diagnosed as a myxoid sarcoma with histopathological features similar to those seen in the preceding biopsy and resection specimens (). The tumor represented had features of a low histologic grade. The patient is currently receiving whole brain radiation. No chemotherapy was administered due to her history of intolerance.
MRI images of the head demonstrating large sellar/sphenoid sinus mass. Sagittal T1 with gadolinium (top) and coronal T1 with gadolinium (bottom).
Pathology specimen from lumbar tumor resection, H&E stain, 200× magnification.