Hello there. . I can understand your concern for your friend. He is suffering from something doesn't mean he has cancer. He could be suffering from simple urinary tract infection why doesn't that cross your mind ever? Or do you want him to have cancer? Kindly take him to a general surgeon, get him checked out, get a ultrasound abdomen done, get a urine test done. Then after examining him, and seeing his reports, the surgeon will be able to help you out. Best regards. Dr. Anil Kumar Jain.

He must be seen by a doctor and undergo sonography etc. as required after clinical checkup. Though kindly do not jump to the fear of cancer for what could be a simple constipation.