Diagnostic value of MDM2 RNA in situ hybridization in atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma.
10.3760/cma.j.cn112151-20211029-00785
- Author:
Chen CHEN
1
;
Xin HE
1
;
Wen Yi JING
1
;
Yan QIU
1
;
Min CHEN
1
;
Tian You LUO
1
;
Xiao Yu LIU
1
;
Hui Juan CHEN
1
;
Hong Ying ZHANG
1
;
Hong BU
1
Author Information
1. Department of Pathology, West China Hospital, Sichuan University, Chengdu 610041, China.
- Publication Type:Journal Article
- MeSH:
Biomarkers, Tumor/genetics*;
Gene Amplification;
Humans;
In Situ Hybridization, Fluorescence;
Liposarcoma/genetics*;
Proto-Oncogene Proteins c-mdm2/genetics*;
RNA
- From:
Chinese Journal of Pathology
2022;51(3):190-195
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the value of MDM2 RNA in situ hybridization (RNA-ISH) in diagnosing atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL) and dedifferentiated liposarcoma (DDL). Methods: A total of 26 ALT/WDL/DDLs diagnosed from March 2017 to May 2019 in West China Hospital, Sichuan University, Chengdu, China and 18 control cases were included. MDM2 RNA-ISH was performed on all samples and compared with the fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) regarding their performance in detecting MDM2. Results: All samples were detected successfully using the three methods. Among 26 ALT/WDL/DDLs, all cases showed MDM2 amplification and positivity for MDM2 RNA-ISH (26/26, 100%). Twenty-four (24/26, 92.3%) of the 26 tested cases were positive for MDM2 IHC while two of them were negative. Eighteen control cases were all negative for MDM2 FISH and RNA-ISH, and 15 (15/18) cases were negative for MDM2 IHC. The sensitivity and specificity of RNA-ISH were both 100%, and those of MDM2 IHC were 92.3% and 83.3%, respectively. Diffuse staining was identified in all MDM2 RNA-ISH positive ALT/WDL/DDLs, but identified in only 8/24 (33.3%) of the MDM2 IHC positive cases. Among the 11 ALT/WDL/DDL samples evaluated on tissue microarray, the positive rate of MDM2 RNA-ISH was 100% with diffuse staining in all cases. The positive rate of MDM2 IHC was 9/11 while only 1 of the 9 cases showed diffuse staining. The result of MDM2 RNA-ISH was identical to that of MDM2 FISH and was overall consistent with that of MDM2 IHC (Kappa=0.763, P<0.001). Conclusions: In ALT/WDL/DDLs, results of MDM2 RNA-ISH are highly consistent with those of FISH. MDM2 RNA-ISH is more sensitive and more specific and has more diffuse positive signals than the IHC. The findings indicate that MDM2 RNA-ISH is highly valuable for the diagnosis and differential diagnosis of ALT/WDL/DDLs.
