Stage IIIC includes: (T3, N3b, M0); (T4a, N3b, M0); (T4b, N3a, M0); (T4b, N3b, M0). T3: Tumor penetrates the subserosal connective tissue without invasion of the visceral peritoneum or adjacent structures. T4a: Tumor invades the serosa (visceral peritoneum). T4b: Tumor invades adjacent structures/organs. N3a: Tumor with metastasis in seven to fifteen regional lymph nodes. N3b: Tumor with metastasis in sixteen or more regional lymph nodes. M0: No distant metastasis. (AJCC 8th ed.) [from NCI]