Laparoscopic nephrectomy for giant staghorn calculus with non-functioning kidneys: Is associated unsuspected urothelial carcinoma responsible for conversion? Report of 2 cases

BACKGROUND-: Neglected renal stones remain a major cause of morbidity in developing countries. They not only result in functional impairment of affected kidney, but also act as an important predisposing factor for development of urothelial neoplasms. It is not uncommon to miss an associated urothelial tumor in a patient of nephrolithiasis preoperatively. CASE PRESENTATION-: In last 3 years, we came across two patients with giant staghorn calculus and poorly functioning kidneys who underwent laparoscopic nephrectomy. In view of significant perirenal adhesions & loss of normal tissue planes both these patients were electively converted to open surgery. The pathological examination of specimen revealed an unsuspected urothelial carcinoma in both these patients. The summary of our cases and review of literature is presented. CONCLUSION-: It is important to keep a differential diagnosis of associated urothelial malignancy in mind in patient presenting with long standing renal calculi. The exact role of a computerized tomography and cytology in preoperative workup for detection of possible associated malignancy in such condition is yet to be defined. Similarly if laparoscopic dissection appears difficult during nephrectomy for a renal calculus with non-functional kidney, keeping a possibility of associated urothelial malignancy in mind it is advisable to dissect in a plane outside gerotas fascia as for radical nephrectomy.