The patient is a 51 year-old female who presented with progressively worsening bilateral lower extremity numbness and gait difficulty for 2 months. Her medical history was significant for stage I breast cancer which was treated with wide-excision lumpectomy followed by radiation therapy. No hormonal therapy nor chemotherapy was administered.
On physical examination, her vital signs were stable and there were no focal cardiac, respiratory or abdominal findings. There was no icterus or palpable lymphadenopathy. There was no palpable hepatosplenomegaly. Her neurological examination revealed intact motor strength and normal tone throughout. There were no cranial nerve or cerebellar deficits. There was diminished sensation to light touch and pin prick at T5-T6 level. Laboratory examination showed a haemoglobin (Hb) level of 10 g/dL, mean corpuscular volume of 78.1 fL, leucocyte count of 10,300/μL, and platelet count 125,000/μL. Liver and renal function tests were also normal. LDH was 272 U/L (range 125-220) at presentation.
The patient had relatively low reticulocyte count, normal iron studies, folate and vitamin B12 levels. Hb electrophoresis revealed Hb A2 (alpha 2 delta 2) 3.8 % (normal range 1.5-3.5) and elevated fetal hemoglobin (alpha 2 gamma 2) HbF 38 % (range 0.0-2.0). Urine and serum protein electrophoreses were unremarkable. Bone marrow karyotyping showed 46 XX. Alpha-globin gene analysis for alpha thalassemia was negative.
MRI of the entire spine revealed abnormal signals of the cervical, thoracic and lumbar vertebrae. A heterogeneous predominantly T2 hyperintense and T1 isointense enhancing lesion (9.7× 1.6× 1.0 cm) extending from the T4 level to the T11 level with near complete effacement of the spinal canal and increased T2 signal within the spinal cord compatible with T5-T6 spinal cord compression. In addition, there were large bulky bilateral enhancing paraspinal lesions from T6 extending to T12 (10.5 × 5.5 × 4.0 cm on the right and 5.0 × 4.2 × 2.2 cm on the left) (Fig. 1). There was a soft tissue presacral mass ajacent to S5 measuring approximately 2.0 × 2.0 × 1.1 cm.
CT scan of the chest/abdomen/pelvis revealed multiple masses in the right hepatic lobe and a large left hepatic lobe mass with nodular peripheral enhancement suspicious for hemangioma, mild splenomegaly, cystic pancreatic head mass, upper retroperitoneal lymphadenopathy, large uterine mass and large anterior abdominal wall mass. The differential diagnosis at this point was metastatic disease with unknown primary, likely breast vs. primary gynecologic malignancy.
The patient underwent a bone marrow biopsy which revealed hypercellular bone marrow with erythroid hyperplasia. Flow cytometry study was negative for leukemia and lymphoma. Bone marrow core biopsy was negative for metastatic disease. For relief of neurological symptoms and final tissue diagnosis, patient underwent T4-T9 total laminectomy and removal of the thoracic epidural tumor. Intra-operative frozen section revealed suspicious lymphoproliferative process. Final pathology of the resected mass revealed dense hematopoietic tissue with erythroid hyperplasia, scattered megaloblastic forms and megakaryocytes, entrapped bony spicules, intervening fibrous septa and adjacent scant adipose tissue (Fig. 2). Immunohistochemistry was negative for cytokeratin AE1/AE3, CD20, CD30, CD1a, and ALK-1. The tissues were positive for hemoglobin A and CD61. Therefore, there was no evidence of leukemia, lymphoma, or other malignancies. These morphologic findings were consistent with extramedullary hematopoiesis.
The final diagnosis in this patient was EMH along the paraspinal areas leading to cytopenia and cord compression.
MRI of the liver was obtained in view of the hepatic mass seen on CT scan of the abdomen and elevated transaminases that the patient developed during the hospital course. MRI findings was compatible with liver hemangioma and the transaminitis was attributed to liver hemangioma versus EMH. Due to the extensive nature of the masses along the bilateral paraspinal areas and cord compression, the patient underwent radiation therapy. The patient had steady improvement and regained muscle strength after rehabilitation.