When rectal cancer spreads out of the intestinal wall and infiltrates more extensively in the pelvis (or when it recurs in the pelvis after surgery), it can cause soreness and swelling in the lumbar and sacral areas. Invasive cervical cancer is often detected during gynecological examination and confirmed by pathological biopsy histological examination. Some cervical cancers are asymptomatic and seen abnormally by the naked eye, so pay attention to the differentiation. Preventive measures for more extensive infiltration in pelvic cavity due to rectal cancer: 1.Take it seriously There are many patients who may be shy of examination or afraid of the pain caused by examination, and take the checklist after the doctor issued it without examination, thus delaying the time of early detection , and such examples are not uncommon in clinical practice. In 80%-90% of rectal cancer, there is blood in stool, and the blood is bright red or dark red, often mixed with mucus or pus. Sometimes the tumor tissues can be seen in the stool, but this is often not the early stage. 3. Early medical consultation Once patients find the above symptoms, they should immediately go to hospital for examination. When consulting the doctor, they should be careful not to easily believe the conclusions drawn by the doctor without examination, such as hemorrhoids or bacillary dysentery. If the doctor does not request an examination, the patient may wish to propose it himself. Generally speaking, rectal finger examination can detect more than 75% of rectal cancers, and simple sigmoidoscopy can detect almost all rectal cancers. 4.Change in bowel habit Change in bowel habit is the earliest and the most common symptom of rectal cancer. Due to the stimulation of cancer, patients may have increased stool frequency or alternating constipation and diarrhea with no obvious reason in a short period of time, with the feeling of incomplete defecation. As the disease progresses and the lesion increases, the cancer may block the rectal outlet, causing constipation, thin or deformed stool, abdominal distension and other symptoms.