Clinicopathological Characteristics and Prognostic Analysis of Platelet-derived Growth Factor Receptor Alpha Mutant Gastrointestinal Stromal Tumors
10.13471/j.cnki.j.sun.yat-sen.univ(med.sci).2021.0417
- VernacularTitle:血小板源性生长因子受体α突变型胃肠间质瘤的临床病理特征及预后分析
- Author:
Xiao-yan WU
1
;
Xiao-yun LIU
1
;
Jia-mei GU
1
;
Yong-shi HUANG
1
;
Fang WANG
1
;
Tao TANG
1
Author Information
1. Sun Yat-sen University Cancer Center//State Key Laboratory of Oncology in South China， Guangzhou 510060， China
- Publication Type:Journal Article
- Keywords:
Gastrointestinal stromal tumor;
PDGFRA;
D842V mutation
- From:
Journal of Sun Yat-sen University(Medical Sciences)
2021;42(4):603-612
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the mutation spectrum of the platelet-derived growth factor receptor Alpha （PDGFRA） gene， clinicopathological characteristics and prognostic factors in 40 cases with gastrointestinal stromal tumors （GIST）， and provide the basis for further targeted therapy. MethodsTotally 40 patients were enrolled between January 2015 to November 2020. These patients were admitted to the Sun Yat-sen University Cancer Center for surgical resection and pathologically diagnosed as GIST， and whose FFPE samples were confirmed with PDGFRA gene mutations in exon 12 or 18 by Sanger sequencing. Immunohistochemistry （IHC） was used to detect the expression of CD117， CD34， DOG-1 and Ki-67 proliferation index in GIST. The clinical and pathological characteristics of the patients were collected， and the risk factors affecting the prognosis of GIST patients with the PDGFRA gene mutations （D842V mutation and non-D842V mutation） were analyzed retrospectively. ResultsIn the 40 patients with PDGFRA mutant GIST， the mutations in exon 18 were the most common， with mutations in exon 18 （97.5%， 39/40）， 34 cases （85.0%， 34/40） with tumors located in the stomach， 32 cases （80%， 32/40） were spindle cell type， 17 cases had the largest tumor diameter between 5 and 10 cm （42.5%）， and 30 cases had the mitotic figures ≤5/50 HPF （75.0%， 30/40）. Most patients had the NIH classification of high-risk （37.5%， 15/40）. There was no correlation between the expression of CD117 and DOG1 and the PDGFRA gene mutations， and they were not supposed to be used as indicators for predicting the PDGFRA gene mutation status. There was no statistically significant difference between the clinical characteristics of the D842V mutation group and the non-D842V mutation group （P>0.05）. Comparison of the clinical characteristics of patients with different genders showed no statistically significant difference （P>0.05）. Log-rank analysis indicated that there was no significant difference in RFS and OS between D842V mutation group and non-D842V mutation group （P>0.05）. There is no significant correlations between the PDGFRA gene mutations and the patients’ gender， age， tumor size， tumor location， the degree of danger and mitotic figures （P>0.05）. ConclusionsD842V is the most common mutation in patients with PDGFRA mutations. The clinicopathological characteristics of between the patients with D842V mutation and those with non-D842V mutation are almost identical. Since PDGFRA D842V is the primary resistance mutation and the D842V mutant GIST patients can benefit from Avapritinib， therefore， gene mutations should be detected before targeted drug therapy.
