1. ¹Department of Pediatrics, University of Yamanashi, School of Medicine, Yamanashi, Japan
2. ²Department of Molecular Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
3. ³Department of Pediatrics, Dokkyo University School of Medicine, Tochigi, Japan
4. ⁴Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
5. ⁵Department of Pediatrics, Kurume University School of Medicine, Kurume, Japan
6. ⁶Department of Pediatrics, Nihon University School of Medicine, Tokyo, Japan
7. ⁷Section of Pediatrics, National Kyushu Cancer Center, Fukuoka, Japan
8. ⁸Division of Cellular Therapy, Institute of Medical Science, University of Tokyo, Tokyo, Japan
9. ⁹Department of Pediatrics, Okayama University Medical School, Okayama, Japan
10. ¹⁰Department of Pediatrics, Yokohama City University School of Medicine, Yokohama, Japan
11. ¹¹Department of Pediatrics, Iwate Medical University School of Medicine, Morioka, Japan
12. ¹²Department of Pediatrics, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, Japan
13. ¹³Department of Hematology and Oncology, Miyagi Children's Hospital, Sendai, Japan
14. ¹⁴Department of Pediatrics, Osaka Rosai Hospital, Sakai, Japan
15. ¹⁵Section of Pediatrics, Anjo Kosei Hospital, Anjo, Japan
16. ¹⁶Department of Pediatrics, Sendai City Hospital, Sendai, Japan
17. ¹⁷Department of Pediatrics, University of Occupational and Environmental Health School of Medicine, Kitakyushu, Japan
18. ¹⁸Department of Pediatrics and Adolescent, Juntendo University School of Medicine, Tokyo, Japan
19. ¹⁹Section of Pediatrics, National Hospital Organization Osaka National Hospital, Osaka, Japan
20. ²⁰Department of Pediatrics, Fukuoka University School of Medicine, Fukuoka, Japan

Correspondence: Dr Takeshi Inukai, Department of Pediatrics, School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan; E-mail: tinukai@yamanashi.ac.jp

Received 28 September 2006; Revised 19 October 2006; Accepted 24 October 2006; Published online 21 December 2006.

Abstract

Hypercalcemia is relatively rare but clinically important complication in childhood leukemic patients. To clarify the clinical characteristics, mechanisms of hypercalcemia, response to management for hypercalcemia, incidence of t(17;19) and final outcome of childhood acute lymphoblastic leukemia (ALL) accompanied by hypercalcemia, clinical data of 22 cases of childhood ALL accompanied by hypercalcemia (>12 mg/dl) reported in Japan from 1990 to 2005 were retrospectively analyzed. Eleven patients were 10 years and older. Twenty patients had low white blood cell count (<20 10⁹/l), 15 showed hemoglobin8 g/dl and 14 showed platelet count 100 10⁹/l. Parathyroid hormone-related peptide (PTHrP)-mediated hypercalcemia was confirmed in 11 of the 16 patients in whom elevated-serum level or positive immunohistochemistry of PTHrP was observed. Hypercalcemia and accompanying renal insufficiency resolved quickly, particularly in patients treated with bisphosphonate. t(17;19) or add(19)(p13) was detected in five patients among 17 patients in whom karyotypic data were available, and the presence of E2A-HLF was confirmed in these five patients. All five patients with t(17;19)-ALL relapsed very early. Excluding the t(17;19)-ALL patients, the final outcome of ALL accompanied by hypercalcemia was similar to that of all childhood ALL patients, indicating that the development of hypercalcemia itself is not a poor prognostic factor.