NCIt definition : Stage IIIB includes: (T3, N1, M0, Any G); (T4, N1, M0, Any G). T3: Tumor invades through
the muscularis propria into the subserosa or the mesoappendix. T4: Tumor invades the
visceral peritoneum, including the acellular mucin or mucinous epithelium involving
the serosa of the appendix or mesoappendix, and/or directly invades adjacent organs
or structures. N1: Tumor involvement of one to three regional lymph nodes (tumor in
lymph node measuring greater than or equal to 0.2 mm) or any number of tumor deposits
is present with no tumor involvement in all identifiable lymph nodes. M0: No distant
metastasis. (AJCC 9th ed.);