Abstract 5193: Case report: Long-term response to Camrelizumab in a pretreated metastatic mixed testicular germ cell tumor patient

Abstract Introduction: To date, very limited information is available about the efficacy of immune checkpoint inhibitor (ICI) therapy in mixed testicular germ cell tumor (TGCT) or variations of DNA damage repair (DDR) genes as predicators for it. Case presentation: We reported a 19-year-old male patient with pretreated metastatic mixed TGCT harboring 5 variations in the BRCA2, MSH6 and PMS2 genes detected using plasma-based circulating tumor DNA (ctDNA). He obtained a durable clinical benefit from single-agent Camrelizumab (a PD-1 inhibitor), with the progression-free survival (PFS) of over 19 months and overall survival (OS) of over 6 years. Conclusion: To the best of our knowledge, this case is the first study of long-term benefit from ICI in a pretreated mixed metastatic TGCT patient harboring 5 variations of DDR genes detected using ctDNA. Table 1. Genomic profile of the patient. Gene Transcript Exon Nucleotide change Alteration Mutant allele frequency/copy number (%) Sequencing depth (×) Medication guides CDH1 NM_004360 exon 15 c.2382delC p.V794fs 0.98 1018 Sensitive to bicalutamide FBXW7 NM_018315 exon 11 c.1761delG p.G587fs 1.88 1009 Sensitive to mTOR inhibitor BCR NM_004327 exon 19 c.3311C>G p.A1104G 1.92 1148 BCR NM_004327 exon 19 c.3316G>A p.D1106N 9.25 1124 BCR NM_004327 exon 22 c.3611C>G p.A1204G 2.29 918 BCR NM_004327 exon 22 c.3615G>A p.T1205T 2.05 926 BCR NM_004327 exon 22 c.3684T>C p.P1228P 2.3 1000 BRAF NM_004333 exon 1 c.64G>A p.D22N 54.15 301 BRCA2 NM_000059 exon 15 c.7522G>A p.G2508S 49.21 1138 CDH1 NM_004360 exon 2 c.144A>G p.R48R 0.7 1001 CYP2B6 NM_000767 exon 5 c.785A>G p.K262R 35.63 595 FCGR3A NM_000569 exon 4 c.634T>G p.F212V 99.75 810 FGFR1 NM_015850 exon 15 c.2017C>T p.R673W 0.84 958 FGFR1 NM_015850 exon 15 c.1991G>T p.W664L 0.25 815 LRIG3 NM_153377 exon 16 c.2589G>A p.T863T 48.91 1143 MSH6 NM_000179 exon 10 c.4006G>T p.V1336F 8.31 349 PMS2 NM_000535 exon 9 c.932A>G p.H311R 0.27 1109 PMS2 NM_000535 exon 9 c.934A>G p.M312V 0.44 1131 PMS2 NM_000535 exon 15 c.2570G>C p.G857A 69.81 573 ROS1 NM_002944 exon 29 c.4783T>C p.L1595L 50.62 1051 SMO NM_005631 exon 3 c.582A>G p.E194E 48.98 1223 TSC2 NM_000548 exon 41 c.5209C>A p.P1737T 1.04 866 Citation Format: Hui Zhang, Da Jiang, Erhong Meng, Wenya Song, Xue Zhang. Case report: Long-term response to Camrelizumab in a pretreated metastatic mixed testicular germ cell tumor patient [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5193.