Stage I includes: pT1-T4, N0, M0, SX. pT1: Testicular cancer which is limited to testis (including rete testis invasion) without lymphovascular invasion. pT2: Testicular cancer which is limited to testis (including rete testis invasion) with lymphovascular invasion or invades hilar soft tissue or epididymis or penetrates visceral mesothelial layer covering the external surface of tunica albuginea with or without lymphovascular invasion. pT3: Testicular cancer in which the tumor invades spermatic cord with or without lymphovascular invasion. pT4: Testicular cancer in which the tumor invades scrotum with or without lymphovascular invasion. N0: Testicular cancer with no regional lymph node metastasis. M0: Testicular cancer without evidence of distant metastasis. SX: Marker studies not available or not performed. (AJCC 8th ed.) [from NCI]