Although high levels of tumor-infiltrating lymphocytes (TILs) generally correlate with good prognosis in high-grade serous ovarian cancer (HGSC) patients, little is known about the phenotype or specificity of these cells. We have recently demonstrated that TIL expressing the intra-epithelial lymphocyte marker CD103 (official name, integrin αE, ITGAE) abundantly infiltrate HGSCs, strongly correl...