Calyceal diverticulum simulating a renal tumor.

Calyceal diverticulum (CD) is a rare anatomic anomaly with an incidence of 0.2% to 0.6% in the patients undergoing renal imaging. They are considered benign lesions and malignancy is exceedingly rare. For diagnosis it is suggested to perform a multiphasic contrast-enhanced computed tomography (CT) evidencing a diverticulum of the pelvicalyceal system with thin-walled cavities communicating with the central collecting system. However, they can be usually mistaken as kidney cancers leading to unjustified nephrectomy. Here, we present a case of a 34-year-old patient who underwent surgery in 2022 due to suspected kidney cancer and histopathological analysis surprisingly reported a CD.

American Confederation of Urology (CAU) experience in minimally invasive partial nephrectomy.

PURPOSE: To describe the perioperative and oncology outcomes in a series of laparoscopic or robotic partial nephrectomies (PN) for renal tumors treated in diverse institutions of Hispanic America from the beginning of their minimally invasive (MI) PN experience through December 2014. METHODS: Seventeen institutions participated in the CAU generated a MI PN database. We estimated proportions, medians, 95 % confidence intervals, Kaplan-Meier curves, multivariate logistic and Cox regression analyses. Clavien-Dindo classification was used. RESULTS: We evaluated 1501 laparoscopic (98 %) or robotic (2 %) PNs. Median age: 58 years. Median surgical time, warm ischemia and intraoperative bleeding were 150, 20 min and 200 cc. 81 % of the lesions were malignant, with clear cell histology being 65 % of the total. Median maximum tumor diameter is 2.7 cm, positive margin is 8.2 %, and median hospitalization is 3 days. One or more postoperative complication was recorded in 19.8 % of the patients: Clavien 1: 5.6 %; Clavien 2: 8.4 %; Clavien 3A: 1.5 %; Clavien 3B: 3.2 %; Clavien 4A: 1 %; Clavien 4B: 0.1 %; Clavien 5: 0 %. Bleeding was the main cause of a reoperation (5.5 %), conversion to radical nephrectomy (3 %) or open partial nephrectomy (6 %). Transfusion rate is 10 %. In multivariate analysis, RENAL nephrometry score was the only variable associated with complications (OR 1.1; 95 % CI 1.02-1.2; p = 0.02). Nineteen patients presented disease progression or died of disease in a median follow-up of 1.37 years. The 5-year progression or kidney cancer mortality-free rate was 94 % (95 % CI 90, 97). Positive margins (HR 4.98; 95 % CI 1.3-19; p = 0.02) and females (HR 5.6; 95 % CI 1.7-19; p = 0.005) were associated with disease progression or kidney cancer mortality after adjusting for maximum tumor diameter. CONCLUSION: Laparoscopic PN in these centers of Hispanic America seem to have acceptable perioperative complications and short-term oncologic outcomes.

Nephron-sparing surgery: our experience in open and laparoscopic approach in 254 cases.

OBJECTIVES: The majority of renal cell carcinomas are now incidentally detected as small renal masses in asymptomatic patients due to the widespread use of ultrasound and new improved noninvasive abdominal imaging modalities. Nephron-sparing surgery is the treatment of choice for patients with small renal masses in presence of normal contralateral kidney or in presence of an anatomic or functional solitary kidney. We reviewed retrospectively our experience in open and laparoscopic partial nephrectomy. METHODS: The records for all patients who underwent nephron-sparing surgery for a renal mass since 1995 at British Hospital of Buenos Aires and Hospital Aleman and since 2000 at Hospital Universitario Austral were reviewed. The most relevant data of 246 patients were collected, with special focus on demographic data, operative details, pathology results, complications and outcome in cancer control. RESULTS: We have performed 254 nephron-sparing surgeries. Open partial nephrectomy was performed in 220 procedures and the laparoscopic partial nephrectomy since 2001 in 34 patients. The indication was elective or relative in 236 patients with 8 patients with bilateral tumors and 18 tumors in a solitary kidney. The pedicle was clamped in 168 procedures with hypothermia in 43 patients. Mean ischemia time was 24.7 minutes. Average tumor size was 3.49 cm. The pathologic findings demonstrate a carcinoma in 193 cases and benign lesions in 61 patients (24%). One patient presented a positive surgical margin in the pathologic examination, but subsequent nephrectomy was negative for residual tumor. One patient presented a pseudo-tumoral mass on follow-up on CT scan and MRI, but nephrectomy was negative for residual tumor. There were postoperative complications in 20 patients (7.9 %). Oncologic follow up was available in 84% of the patients for an average of 46.6 months showing progression with metastasis in 8 patients. Local recurrence was observed in 4 patients (2%). One patient developed a tumor in the contralateral kidney 20 months after partial nephrectomy and another one 10 years later. The cancer specific survival and overall survival rates were 98 % and 95% respectively. In the last year the laparoscopic approach duplicated the indications of all previous years. CONCLUSIONS: Open partial nephrectomy is considered nowadays the gold standard treatment of small renal masses, and in our experience it is a safe and effective technique of treatment of these tumors. The evolution of the technology and the acquirement of laparoscopic skills allow us in selected cases to duplicate the open approach in a laparoscopic way, obtaining similar results.

Nefrectomía parcial a cielo abierto y laparoscópica: Nuestra experiencia en 254 cirugías / Nephon-sparing surgery: our experience in open and laparoscopic approach in 254 cases

OBJETIVOS: La mayoría de los tumores de riñón se detectan actualmente como una masa renalpequeña en pacientes asintomáticos, por el uso generalizado de la ecografía y otras modalidades no invasivas de exploración abdominal. La cirugía conservadorade riñón de estas masas renales pequeñas es el tratamiento de elección, tanto en pacientes con el riñón contralateral sano como en aquellos pacientes que presentanalgún grado de deterioro en la función renal o son monorrenos funcionales o anatómicos. Revisamos retrospectivamente nuestra experiencia en cirugía conservadorade riñón en masas tumorales, a cielo abierto y por la vía laparoscópica.MÉTODO: Se revisaron las historias clínicas de aquellos pacientes a los cuales se diagnosticó una masa ocupanterenal y se los trató con cirugía conservadora renal en el Hospital Británico de Buenos Aires y Hospital Alemán desde el año 1995 y el Hospital Universitario Austral desde el año 2000. Se tabularon todos los datos de interés de 246 pacientes, se analizaron las técnicas empleadas,complicaciones y resultados y se compararon con otras series de referencia.RESULTADOS: Se realizaron 254 cirugías conservadorasde riñón. La cirugía a cielo abierto fue realizada en 220 casos y la nefrectomía parcial laparoscópica desde el año 2001 en 34 pacientes. La indicación fue electiva o relativa en 236 pacientes, 8 pacientes presentaron tumores bilaterales y hubo 18 cirugías en pacientes monorrenos. El clampeo del pedículo se realizóen 168 procedimientos, con hibernación en 43 pacientes con un tiempo promedio de 24,7 minutos...(AU)

OBJECTIVES: The majority of renal cell carcinomas are now incidentally detected as small renal masses in asymptomatic patients due to the widespread use of ultrasound and new improved noninvasive abdominal imaging modalities. Nephron-sparing surgery is the treatment of choice for patients with small renal masses in presence of normal contralateral kidney or in presence of an anatomic or functional solitary kidney. We reviewed retrospectively our experience in open and laparoscopic partial nephrectomy.METHODS: The records for all patients who underwent nephron-sparing surgery for a renal mass since 1995 at British Hospital of Buenos Aires and Hospital Aleman and since 2000 at Hospital Universitario Austral were reviewed. The most relevant data of 246 patients were collected, with special focus on demographic data, operative details, pathology results, complications and outcome in cancer control.RESULTS: We have performed 254 nephron-sparing surgeries. Open partial nephrectomy was performed in 220 procedures and the laparoscopic partial nephrectomy since 2001 in 34 patients. The indication was elective or relative in 236 patients with 8 patients with bilateral tumors and 18 tumors in a solitary kidney. The pedicle was clamped in 168 procedures with hypothermia in 43 patients. Mean ischemia time was 24.7 minutes. Average tumor size was 3.49 cm...(AU)