clinical tumor stage group according to AJCC 7th edition metadata complete Stage 0 (AJCC 7th) Stage 0 (AJCC 7th) Chris Stoeckert, Helena Ellis A clinical tumor stage group according to AJCC 7th edition indicating a carcinoma in situ (or melanoma in situ for melanoma of the skin or germ cell neoplasia in situ for testicular germ cell tumors) and generally is considered to have no metastatic potential. Stage 0 A clinical tumor stage group according to AJCC 7th edition indicating a carcinoma in situ (or melanoma in situ for melanoma of the skin or germ cell neoplasia in situ for testicular germ cell tumors) and generally is considered to have no metastatic potential. NCI BBRB https://en.wikipedia.org/wiki/Cancer_staging