Stage IIIC includes: T3c, N0/N1, M0. T3c: Primary peritoneal cancer with macroscopic peritoneal metastasis beyond the pelvis more than 2 cm in greatest dimension with or without metastasis to the retroperitoneal lymph nodes (includes extension of tumor to capsule of liver and spleen without parenchymal involvement of either organ). N0: No regional lymph node metastasis. N1: Positive retroperitoneal lymph nodes only (histologically confirmed). M0: No distant metastasis. (AJCC 8th Ed.) [from NCI]