title: Richter's Syndrome with Hypercalcemia Induced by Tumor-Associated Production of Parathyroid Hormone-Related Peptide.
abstract: Humoral hypercalcemia due to parathyroid hormone-related peptide (PTHrP) elevation is a well-known complication of various malignancies, but the situation is rare concerning hematological malignancies except for adult T-cell leukemia/lymphoma. We report a case of Richter's syndrome with humoral hypercalcemia, and demonstrate by reverse transcription polymerase chain reaction (RT-PCR) that peripheral blood PTHrP levels were 2,500-fold higher compared to healthy controls. PTHrP production by tumor cells in chronic lymphocytic leukemia (CLL) and Richter's syndrome has been previously demonstrated by nonquantitative methods such as immunohistochemistry and northern blot analysis, but this is the first report using the RT-PCR method. The presented case did not have hypercalcemia when initially diagnosed as small lymphocytic lymphoma (SLL), and as reported earlier, the development of hypercalcemia may be an indication of the transformation to Richter's syndrome in patients with CLL/SLL.
authors.affiliation: Division of Hematology, Department of Medicine, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Watanabe
authors.affiliation: Division of Hematology, Department of Medicine, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Yasuda
authors.affiliation: Department of Transfusion Medicine and Stem Cell Regulation, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Soji
authors.initials: S
authors.lastname: Morishita
authors.affiliation: Division of Hematology, Department of Medicine, Juntendo University School of Medicine, Tokyo, Japan; Department of Internal Medicine, Kohsei Chuo General Hospital, Tokyo, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Aota
authors.affiliation: Department of Medical Oncology, The Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Tomomatsu
authors.affiliation: Division of Hematology, Department of Medicine, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Department of Transfusion Medicine and Stem Cell Regulation, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Akimichi
authors.initials: A
authors.lastname: Ohsaka
authors.affiliation: Division of Hematology, Department of Medicine, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Komatsu
keywords: Chronic lymphocytic leukemia; Hypercalcemia; Parathyroid hormone-related peptide; Richter's syndrome; Small lymphocytic leukemia