Rectal cancer lymphatic metastasis is not an early symptom. In early stage, the size of rectal cancer is relatively small, and patients mostly have no obvious symptoms, which are mostly found during anal diagnosis and colonoscopy. When the tumor progresses to a certain degree, patients may have anal swelling, urgency (discomfort in the lower abdomen, wanting to defecate, feeling of incomplete defecation after defecation), change of defecation habit, mucus stool, abdominal pain, abdominal distension and other manifestations. Lymphatic metastasis is the main spreading pathway of rectal cancer. According to TNM staging of rectal cancer, early rectal cancer means that the primary tumor is only confined to the intramucosal or submucosal layer without lymphatic metastasis, while the presence of regional lymphatic metastasis in rectal cancer belongs to stage III rectal cancer, and when the tumor develops distant lymph node metastasis, then it belongs to stage IV rectal cancer, which belongs to the advanced stage of rectal cancer. When lymphatic metastasis of rectal cancer occurs in middle or late stage, patients should pay attention to it and consult doctor in time, who will analyze it comprehensively according to the specific conditions, make clear diagnosis and carry out targeted treatment. Patients should not judge on their own according to one examination result in order to avoid delaying their condition.