A 64-year-old man was diagnosed as having
urticaria pigmentosa in 1998, and treated with
PUVA therapy. In January 2002, X-ray imaging revealed
osteosclerosis was detected in the systemic bone and bone scintigraphy. A bone marrow aspiration sample was not obtained due to a dry tap. CT scans showed hepatosplenomegaly and mesenteric
lymphadenopathy.
Myelofibrosis and diffuse mast cell infiltration were revealed by a bone marrow biopsy, and a diagnosis of
systemic mastocytosis with severe
osteosclerosis and
myelofibrosis was made. In October 2003, he was admitted to our hospital because of mid
back pain. A neurological examination showed
muscle weakness in the upper and lower limbs, sensory disturbance below the level of Th4 and urinary obstruction. T1 and T2 weighted images of MRI demonstrated a high intensity epidural mass lesion extending from the vertebral level of C5 to Th2 and severely compressing the spinal cord. We considered the possibility of the invasion of the spinal canal by the
mastocytosis. The patient was treated with
interferon alpha-2b (IFN-alpha2b) and
prednisolone. Subsequently, the motor and sensory disturbances were gradually alleviated, and spinal MRI confirmed a marked reduction in the size of the
epidural tumor. However, the patient became resistant to
interferon, and died of
multiple organ failure in spite of
steroid pulse and
cladribine therapies. Multiple organ infiltration by mast cells was revealed at autopsy.