1. ¹Department of Regeneration Medicine for Hematopoiesis, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
2. ²Department of Hematology/Oncology, National Kyushu Cancer Center, Fukuoka, Japan
3. ³Department of Hematology, Tokyo Medical University, Tokyo, Japan
4. ⁴Department of Hematology, Jichi Medical School, Tochigi, Japan
5. ⁵Department of Hematology/Oncology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
6. ⁶Cell Therapy and Transplantation Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
7. ⁷Division of Hematology, Internal Medicine, Showa University Fujigaoka Hospital, Yokohama, Japan
8. ⁸Department of Hematology, Dokkyo University School of Medicine, Tochigi, Japan
9. ⁹Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Saitama, Japan

Correspondence: Dr S Ogawa, Department of Hematology and Oncology, Department of Regeneration Medicine for Hematopoiesis, Graduate School of Medicine, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. E-mail: sogawa-tky@umin.ac.jp

Received 24 August 2006; Revised 25 January 2007; Accepted 25 January 2007; Published online 22 February 2007.

Abstract

The unbalanced translocation, der(1;7)(q10;p10), is one of the characteristic cytogenetic abnormalities found in myelodysplastic syndromes (MDS) and other myeloid neoplasms. Although described frequently with very poor clinical outcome and possible relationship with monosomy 7 or 7q- (-7/7q-), this recurrent cytogenetic abnormality has not been explored fully. Here we analyzed retrospectively 77 cases with der(1;7)(q10;p10) in terms of their clinical and cytogenetic features, comparing with other 46 adult -7/7q- cases without der(1;7)(q10;p10). In contrast with other -7/7q- cases, where the abnormality tends to be found in one or more partial karyotypes, der(1;7)(q10;p10) represents the abnormality common to all the abnormal clones and usually appears as a sole chromosomal abnormality during the entire clinical courses, or if not, is accompanied only by a limited number and variety of additional abnormalities, mostly trisomy 8 and/or loss of 20q. der(1;7)(q10;p10)-positive MDS cases showed lower blast counts (P<0.0001) and higher hemoglobin concentrations (P<0.0075) at diagnosis and slower progression to acute myeloid leukemia (P=0.0043) than other -7/7q- cases. der(1;7)(q10;p10) cases showed significantly better clinical outcome than other -7/7q cases (P<0.0001). In conclusion, der(1;7)(q10;p10) defines a discrete entity among myeloid neoplasms, showing unique clinical and cytogenetic characteristics.