[Acute lymphocytic leukemia (L1) preceded by hypercalcemia].

A 37-year-old female with hypercalcemia presented with lumbago, nausea and vomiting. Peripheral blood (PB) and bone marrow (BM) smears revealed no lymphoblasts on the first admission. The value of parathyroid hormone related protein (PTHrP) was increased and osteoporosis was found in the lumbar vertebrae. After 5 months, diagnosis of acute lymphocytic leukemia (ALL) was made on the evidence that lymphoblasts were found in PB (1%) and in BM (98%). Treatment with vincristine, daunorubicin, prednisolone and L-asparaginase achieved complete remission (CR) and the serum calcium level returned to the normal range. She has maintained CR, and is currently treated with consolidation therapy by cyclophosphamide and methotrexate. Acute leukemia is known to be rarely accompanied with hypercalcemia. This rare case was accompanied with hypercalcemia in acute leukemia. Hypercalcemia appeared to be attributable to the increased bone absorption by PTHrP derived from tumor cells. This important case will help understanding the etiology of hypercalcemia associated with ALL.