The abdominal distension and pain of renal pelvic tumor is considered to be caused by the growth of tumor, and it may also be caused by bladder stones, female patients should also consider pelvic inflammatory disease and other diseases, as well as other diseases such as endometritis. 1. Tumor growth: when patients with renal pelvis tumor have the symptom of abdominal distension and pain, it may be because the tumor is growing, when the tumor grows to a certain size, it will pull the renal peritoneum of the patient, which leads to the symptom of abdominal distension and pain in the patient. 2. Bladder stones: bladder stones are mainly caused by urine retention in the bladder, and the main symptoms of patients are pain in the lower abdomen, difficulty in urination, hematuria and so on. If patients with renal pelvis tumor have bladder stones, it will also lead to abdominal distension and pain. 3. Pelvic inflammatory disease: Pelvic inflammatory disease is mainly caused by infection of bacteria and other pathogens, and the patient will have symptoms such as lower abdominal pain, increased vaginal secretion, fever and so on. If female renal pelvis tumor patients are complicated with pelvic inflammatory disease, the patients will also have the phenomenon of abdominal distension and pain. 4. Other diseases, such as endometritis, ovarian cysts, etc., can also lead to abdominal distension and pain in patients with renal pelvis tumor. When patients with renal pelvis tumor have symptoms of abdominal distension and pain, they should consult doctor in time to clarify the cause of the disease and follow the doctor’s instruction.