Rectal PT3N0M0 is defined as rectal cancer penetrating the intrinsic muscular layer to the subplasma membrane without lymph node and distant metastasis based on pathological findings. TNM staging is mostly used for rectal cancer, T stands for primary tumor lesion, N stands for lymphatic metastatic situation and M stands for distant metastatic situation assessment.TNM staging also has cTNM staging based on clinical imaging examination, pTNM staging based on pathological examination results, pyTNM staging based on pathological examination results after neoadjuvant therapy and so on. T3 means that the primary tumor foci of rectal cancer have penetrated the intrinsic muscular layer to reach the subplasma membrane or invaded the pararectal tissues without peritoneal coverage. n0 means no lymph node metastasis, and M0 means no distant metastasis. pT3N0M0 belongs to stage IIA, which is an earlier stage of rectal cancer. It is recommended that patients actively choose appropriate treatment plan after fully communicating with specialists to control the development of cancer as early as possible and the aggravation of the disease, which is conducive to a better cure.