Hello and welcome to HCM. Thank you for your query. A lesion is an abnormality in the muscle or tissue caused by damage, wound, disease or trauma. This lesion in your case is iatrogenic, which means a condition caused by a doctor. As the procedural removal of the tumor required access through the urinary bladder, this incision/hole was created. But, without fail, this incision would have been closed by the end of the procedure. The body s normal response to any such wound or injury would be to promote healing and the prevent infections. Although your doctor would have also prescribed medication to promote the same, the body initiates a response to heal the wound. During this process scar tissue is formed. This scar tissue goes about formation of new tissue and contraction of the wound site. This response would have caused the pain and pulling sensation that you experience. Please do not worry, as this is considered normal. Unless you experience any other symptoms like blood in your urine, fever, chills, etc; you need not worry about this. I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications. I would gladly help you. Best wishes.