Long-term survival in multiresistant metastatic choriocarcinoma after pembrolizumab treatment: A case report.

•Checkpoint inhibitor therapy affecting PD-L1 as treatment for advanced solid tumors.•Success in trial pembrolizumab therapy in multiresistant metastatic choriocarcinoma.•Long-term remission after pembrolizumab therapy in multiresistant choriocarcinoma.•Only six reported cases, one with comparable follow-up and outcome.

Core 2 ß1,6-N-acetylglucosaminyltransferases accelerate the escape of choriocarcinoma from natural killer cell immunity.

Hyperglycosylated human chorionic gonadotropin (H-hCG) is secreted from choriocarcinoma and contains a core2 O-glycan formed by core2 ß1,6-N-acetylglucosaminyl transferase (C2GnT). Choriocarcinoma is considered immunogenic as it is gestational and contains paternal chromosomal components. Here we examined the function of C2GnT in the evasion of choriocarcinoma cells from natural killer (NK) cell-mediating killing. We determined that C2GnT is highly expressed in malignant gestational trophoblastic neoplasms. C2GnT KO downregulates core2 O-glycan expression in choriocarcinoma cells, which are more efficiently killed by NK cells than control cells. C2GnT KO cell containing tumor necrosis factor-related apoptosis inducing ligand have lower viability than control cells. Additionally, poly-N-acetyllactosamine in core2 branched oligosaccharides on MHC class I-related chain A (MICA) and mucin1 (MUC1) is significantly reduced in C2GnT KO cells. Meanwhile, the cumulative survival rate of nude mice inoculated with C2GnT KO tumors was higher than that of the control group. These findings suggest that choriocarcinoma cells may escape NK cell-mediated killing via glycosylation of MICA and MUC1.

Epithelioid trophoblastic tumor presenting as a Caesarean scar defect: A case report.

BACKGROUND: Epithelioid trophoblastic tumor is a rare form of gestational trophoblastic neoplasia. We present the first known case of this rare malignancy presenting as a Caesarean scar defect. CASE: A patient with 3 prior Caesarean sections presented with vaginal bleeding 2 months following management of retained products of conception. Her hCG was negative. She underwent surgical repair of a Caesarean scar defect, and pathology was consistent with epithelioid trophoblastic tumor. CONCLUSION: This case highlights the possibility of malignancy presenting to the general gynecologist as a Caesarean scar defect. The diagnosis of gestational trophoblastic neoplasia should always be considered in the differential diagnosis of a patient with postpartum vaginal bleeding. Limited evidence on fertility conserving treatment of epithelioid trophoblastic tumors does not seem favorable.