Clinicopathologic characteristics,gene mutation profile and prognostic analysis of thyroid diffuse large B-cell lymphoma / 上海交通大学学报（医学版）

ABSTRACT

Objective·To analyze the clinicopathologic characteristics,gene mutation profile,and prognostic factors of thyroid diffuse large B-cell lymphoma(DLBCL).Methods·From November 2003 to December 2021,a total of 66 patients with thyroid DLBCL[23 cases(34.8%)with primary thyroid DLBCL,and 43 cases(65.2%)with secondary thyroid DLBCL]admitted to Ruijin Hospital,Shanghai Jiao Tong University School of Medicine were retrospectively analyzed for their clinicopathological data,survival and prognostic factors.Gene mutation profiles were evaluated by targeted sequencing(55 lymphoma-related genes)in 40 patients.Results·Compared to primary thyroid DLBCL,secondary thyroid DLBCL had advanced ratio of Ann Arbor stage Ⅲ?Ⅳ(P=0.000),elevated serum lactate dehydrogenase(LDH)(P=0.043),number of affected extranodal involvement≥2(P=0.000),non-germinal center B cell(non-GCB)(P=0.030),BCL-2/MYC double expression(DE)(P=0.026),and international prognostic index(IPI)3?5-scores(P=0.000).The proportion of patients who underwent thyroid surgery(P=0.012)was lower than that of patients with primary thyroid DLBCL.The complete remission(CR)rate in primary thyroid DLBCL patients was higher than that in secondary thyroid DLBCL patients(P=0.039).Fifty-five patients(83%)received rituximab combined with cyclophosphamide,doxorubicin,vincristine,and prednisone(R-CHOP)-based first-line regimen.The estimated 5-year progression free survival(PFS)rate of primary thyroid DLBCL patients was 95.0%,higher than the 49.7%of the secondary patients(P=0.010).Univariate analysis showed that Ann Arbor Ⅲ?Ⅳ(HR=4.411,95%CI 1.373?14.170),elevated LDH(HR=5.500,95%CI 1.519?19.911),non-GCB(HR= 5.291,95%CI 1.667?16.788),and DE(HR=6.178,95%CI 1.813?21.058)were adverse prognostic factors of PFS in patients with thyroid DLBCL.Ann Arbor Ⅲ?Ⅳ(HR=7.088,95%CI 0.827?60.717),elevated LDH(HR=6.982,95%CI 0.809?60.266),and DE(HR=18.079,95%CI 1.837?177.923)were adverse prognostic factors of overall survival(OS).Multivariate analysis showed that Ann Arbor Ⅲ?Ⅳ(HR=4.693,95%CI 1.218?18.081)and elevated LDH(HR=5.058,95%CI 1.166?21.941)were independent adverse prognostic factors of PFS in patients with thyroid DLBCL.Targeted sequencing data showed mutation frequency>20%in TET2(n=14,35%),KMT2D(n=13,32%),TP53(n=11,28%),GNA13(n=10,25%),KMT2C(n=9,22%),and TP53 were adverse prognostic factors of PFS in patients with thyroid DLBCL(P=0.000).Conclusion·Patients with primary thyroid DLBCL have better PFS and OS than those with secondary thyroid DLBCL.Ann Arbor Ⅲ?Ⅳ,elevated LDH,non-GCB,and DE(MYC and BCL2)are adverse prognostic factors in thyroid DLBCL.TET2,KMT2D,TP53,GNA13,and KMT2C are commonly highly mutated genes in thyroid DLBCL,and the prognosis of patients with TP53 mutations is poor.