Abstract Two case reports are presented with an important question what should be done when an endoscopic appearance of the urotherial lesion is unavailable. As seen in clinical practice, many patients choose nephroureterectomy with frequent follow up procedures. The other question raised is that what should be done when the lesions are ureteroscopically inaccessible. These patients can avail the advantages of radical treatment without accepting the probable as initial form of treatment to evade the risk and detriments of unnecessary additional endoscopic procedures. Introduction The advent of flexible ureteroscopy and percutaneous nephroscopy seemed to change the ureteropelvic urothelial carcinoma (UC) diagnosis and management dramatically. This was true in many areas. 1,2 In most cases, ureteropelvic UC is demonstrated as a filling defect in excretory urography (IVP) or contrast enhanced computerized tomography (CT). The differential diagnosis includes fungal bezoars, sloughed papillae, clots, overlying bowel gas and stones. 3 Emergence of flexible ureteroscopy heralded the availability of a ready in use technique to deal with these rare but potentially misleading differential diagnoses. At the same time with prevailing experience with the instrument, concerns rose about the danger of extravasation, retrograde and extra- ureteral seeding. Although many studies have shown the safe nature of flexible ureteroscopy in these cases, the danger still is present. 4 Similar concerns have been raised for antegrade renoscopy. Despite low incidence, cases of percutaneous tract seeding have been reported. 5 It is still undetermined whether endoscopic visualization is necessary for the diagnosis of ureteropelvic UC in the case that endoscopic ablation seems impossible due to the radiographic appearance of the lesion or to lacking required equipment in the centre. Two cases of ureteropelvic UC are presented where an endoscopic appearance of the lesion was not possible. Case 1: The patient was a 53-year-old man with the main complaint of gross haematuria for 2 months. He had no flank pain, irritative symptoms, and constitutional signs and symptoms. His past history was uneventful. He was taking aspirin since 2 years and had a history of cigarette smoking. Ultrasonography revealed mild hydronephrosis in the left kidney with left proximal ureter dilatation. IVP demonstrated a filling defect in the pelvis of left kidney (Figure-A). CT scan showed an 18.8-mm mass in the pelvis of left kidney and mild hydronephrosis. Other findings were unremarkable. Bladder was normal on cystoscopy. Left ureteroscopy was performed but the pelvis could not be reached because of tightness in the middle left ureter. Selective urine cytology was obtained from the left ureter. Urine cytology from left ureter revealed mildly atypical urothelial cell clusters, but the probability of low grade papillary tumour was not excluded. Nephroscopy and biopsy from suspicious lesion of left renal pelvis was performed. Pathology report was non-specific inflammatory fibroconnective tissue. On suspicion of urothelial carcinoma, the patient underwent nephroureterectomy and resection of bladder cuff. Histopathologic examination showed low grade papillary urothelial carcinoma (Stage T1). Case 2: A 57-year-old female presented with a history of gross haematuria and clot passage for 8 months. She did not mention any constitutional signs or symptoms. Her past history was unremarkable except for a history of 230 J Pak Med Assoc Case Report Lack of visual endoscopic appearance of ureteropelvic urothelial cancer; Is it a deterrence for nephroureterectomy? A case study and literature review Nasser Simforoosh, Seyed-Mohammad Ghohestani, Hamidreza Abdi, Mohammadhossein Soltani, Abbas Basiri Urology and Nephrology Research Center (UNRC), Shahid Labbafinejad Medical Center, Shahid Beheshti University, M.C.(SBMU), Tehran, I.R. Iran. Figure-A: Excertion of both kidneys are normal. A filling defect in the pelvis of left kidney is seen.