This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Testis and scrotum, Subject name: Surgery
[{'content': 'High inguinal orchidectomy specimen showed Teratoma testis with involvement of epididymis; stage is: \nSelect and explain. \nA. T1, B. T2, C. T3, D. T4b', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 8th AJCC (2017) TNM STAGING FOR TESTICULAR TUMORS T: Primary Tumor N: Regional Lymph nodes p Tis: Intratubular germ cell neoplasia (carcinoma in situ) N1: LN mass <= cm or multiple LN masses, none > 2 cm pT1: Limited to the testis & epididymis and no vascular/ lymphatic invasion; Tumor may invade tunica albuginea but not tunica vaginalis N2: LN mass, > 2 cm but < 5 cm or multiple LN masses, any one mass > 2 cm but not < 5 cm pT2: Limited to the testis & epididymis with vascular/ lymphatic invasion or extending through tunica albuginea with involvement of tunica vaginalis. N3: LN mass > 5 cm pT3: Invades the spermatic cord with or without vascular/ Lymphatic invasion M: Distant metastases pT4: Invades the scrotum with or without vascular/ lymphatic invasion M1: Non-regional nodal or pulmonary metastases M2: Non-pulmonary visceral masses', 'role': 'assistant'}]