OC TLS gene signature (CETP, CCR7, SELL, LAMP3, CCL19, CXCL9, CXCL10, CXCL11, CXCL13) identified & validated.Signature predicts prognosis & immunotherapy benefit.Confirmed improved survival values of TLS & TLS play an important role in tumor immunity.Gene signature proposed as prognostic biomarker & means to guide immunotherapy in OC. Here, CXCL13 is linked to neoplasm.