[Chromosome 13q deletion detected by interphase FISH in multiple myeloma: a study of 100 cases in China].
OBJECTIVE
To summarize the clinical significance and 13q- characters of 100 multiple myeloma (MM) patients detected by interphase fluorescence in situ hybridization (i-FISH).


METHODS
Specimens of bone marrow were collected from 100 patients with MM who visited the Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences in Tianjin, China. Chromosome R-banding analysis and i-FISH were conducted.


RESULTS
(1) i-FISH was used to investigate 100 patients with MM, whose median age was 56 years and 19 (19.0%) cases showed chromosome 13q deletions/monosony13 (Delta13); conventional cytogenetics (CC) revealed informative MM karyotypes in 24 patients (24.0%),with Delta13 in 10 (10.0%) of them. Detection rate of the two methods had no significant difference (P = 0.053), but in newly diagnosed patients i-FISH was much more sensitive than CC test (Detection rate, 25.3% vs 9.3%, P = 0.008). (2) Among the whole cases, 93 of them had complete follow-up information. The overall survival (OS) of the 93 patients was 41 (1-69) months. Univariate analysis showed that the positive rate of Delta13 detected by i-FISH >50%, clonal chromosome 13 abnormality (C13A), nonhyperdiploidy, Delta13 detected by both CC and i-FISH, beta2-MG > or = 3.5 mg/L were associated with significantly shorter OS. Multivariate analysis indicated that the positive rate of Delta13 detected by i-FISH > 50% and beta2-MG > or = 3.5 mg/L were the independent unfavorable factors. (3) According to the two independent unfavorable factors mentioned above, we divided the 93 patients into three groups: low-risk, standard-risk and high-risk. And there were significant differences of OS among the 3 groups (P < 0.05).


CONCLUSIONS
(1) FISH studies demonstrate a high sensitivity at detecting chromosome 13 abnormality and should be used in the routine evaluation of MM. (2) The positive rate of Delta13 detected by i-FISH > 50% and beta2-MG > or = 3.5 mg/L were the independent adverse prognostic factors.
Li
Qian
Q
Institute of Hematology and Blood Disease Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, China.
Lu
Yun
Y
Wang
Ya-Fei
YF
Liu
Xu-Ping
XP
Qi
Jun-Yuan
JY
Zou
De-Hui
DH
Zhao
Yao-Zhong
YZ
Qiu
Lu-Gui
LG
D000328:Adult; D000368:Aged; D002872:Chromosome Deletion; D002882:Chromosomes, Human, Pair 13; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis / Q000235:genetics*; D011379:Prognosis