[A Case of Sigmoid Colon Cancer with Horseshoe Kidney].

We reported a case of sigmoid colon cancer with horseshoe kidney. A 79-year-old man had lower abdominal pain and underwent colonoscopy. The results of colonoscopy revealed sigmoid cancer. Preoperative computed tomography revealed horseshoe kidney. He underwent radical laparoscopic surgery. The histopathological diagnosis was pStage Ⅱa(The 9th Edition). He has not recurred 22 months later after operation. Surgery for colorectal cancer with congenital anomalies of the urinary tract requires attention to intraoperative secondary injuries. Therefore, preoperative evaluation using 3D-CT is useful tool for safety. Operating the proper dissecting normal layer would make safe laparoscopic operation possible without unexpected injuries.

Robot-assisted laparoscopic surgery for rectal cancer in a patient with a horseshoe kidney: A case report.

A 52-year-old, Japanese man presented to the hospital with a complaint of anal bleeding, and detailed examination resulted in a diagnosis of locally advanced rectal cancer. The patient underwent total neoadjuvant therapy followed by short-course radiation therapy and consolidation chemotherapy, which provided a partial response. After preoperative contrast-enhanced computed tomography showed a horseshoe kidney, robot-assisted, precise, laparoscopic, low anterior resection with D3 dissection and ileostomy construction was performed. The horseshoe renal isthmus was elevated surrounding the inferior mesenteric artery, and the left ureter and seminal vessels ran in front of the kidney. The hypogastric nerve traveled ventral to the horseshoe kidney. With robotic surgery, it was possible to perform more precise surgery while recognizing vascular and nerve anatomy in a rectal cancer patient with a horseshoe kidney due to good three-dimensional visibility and articulated forceps manipulation.

Laparoscopic retroperitoneal heminephrectomy for renal cell carcinoma in horseshoe kidney: a case report and review of the literature.

INTRODUCTION: In this case report, we demonstrate our technique of a retroperitoneal laparoscopic heminephrectomy for a T1b right hilar tumor in a horseshoe kidney. CASE PRESENTATION: A 77-year-old Vietnamese woman presented to the hospital because of right flank pain. On presentation, her serum creatinine was 0.86 mg/dL and glomerular filtration rate was 65.2 mL/minute/1.73 m2. According to her renal scintigraphy, glomerular filtration rates of the right and left moieties were 24.2 and 35.5 mL/minute, respectively. Computed tomography imaging demonstrated a 5.5 × 5.0 cm solid hilar mass with a cT1bN0M0 tumor stage was in the right moiety. After discussion, the patient elected a minimally invasive surgery to treat her malignancy. The patient was placed in a flank position. We used Gaur's balloon technique to create the retroperitoneal working space, and four trocar ports were planned for operation. Three arteries were dissected, including two arteries feeding the right moiety, one artery feeding the isthmus, and one vein, which was clipped and divided by Hem-o-lok. The isthmusectomy was performed with an Endostapler. Consequently, the ureter was clipped and divided. Finally, the whole right segment of the horseshoe kidney was mobilized and taken out via the flank incision. RESULTS: The total operative time was 250 min with an estimated blood loss of 200 mL. The patient's serum creatinine after surgery was 1.08 mg/dL, and glomerular filtration rate was 49.47 mL/minute/1.73 m2. The patient was discharged on postoperative day #4 without complication. Final pathologic examination of the tumor specimen revealed a Fuhrman grade II clear cell renal cell carcinoma, capsular invasion, with negative surgical margins. After a three-month follow-up, the serum creatinine was 0.95 mg/dL, and glomerular filtration rate was 57.7 mL/minute/1.73 m2. Local recurrence or metastasis was not detected by follow-up computed tomography imaging. CONCLUSIONS: Retroperitoneal laparoscopic heminephrectomy is a safe and feasible technique for patients with renal cell carcinoma in a horseshoe kidney and may be particularly useful in low income settings without access to robotic technology.

Giant left pheochromocytoma with vascular anomalies and pelvic horseshoe kidney: a case report.

BACKGROUND: Pheochromocytoma is a neuroendocrine tumor, and its treatment is dependent on surgical resection. Due to the wide availability of cross-sectional imaging, pheochromocytomas are commonly seen as small tumors less than 10 cm in size and are mostly treated with minimally invasive surgery. Their concomitant presence with horseshoe kidney or other anatomical and vascular anomalies is rare. Herein, we present a surgically complex giant pheochromocytoma case who underwent an open left radical adrenalectomy. CASE PRESENTATION: A 41-year-old Hispanic female presented with a 12 × 8 cm left hypervascular adrenal mass, pelvic horseshoe kidney, and severely dilated large left retro-aortic renal vein which branched into a left adrenal vein, congested left ovarian vein, and left uterine plexus. She was managed with insulin and metformin for uncontrolled diabetes with an A1c level of 9% and doxazosin for persistent hypertension. Clinical diagnosis of pheochromocytoma was confirmed with elevated urine and serum metanephrine and normetanephrine. The pre-operative ACTH was within normal range with a normal dexamethasone suppression test and 24-hour urine free cortisol. The adrenalectomy of the highly aggressive adrenal mass was performed via open approach to obtain adequate surgical exposure. Due to the large size of the tumor and its significant involvement with multiple adjacent structures, coordination with multiple surgical teams and close hemodynamic monitoring by anesthesiology was required for successful patient outcomes including preservation of blood supply to the pelvic horseshoe kidney. The histopathological diagnosis was pheochromocytoma with negative surgical margins. The patient was followed at 1, 4, 12, and 24 weeks postoperatively. She had a normal postoperative eGFR and was able to discontinue antihypertensive and antidiabetic medications at four weeks. She had transient adrenal insufficiency, which resolved at five months. The horseshoe kidney was intact except for a minimal area of hypo-enhancement in the left superior renal moiety due to infarction, which was significantly improved at six months. CONCLUSION: Our patient had a giant pheochromocytoma with anatomical variations complicating an already surgically challenging procedure. Nonetheless, with multiple provider collaboration, detailed pre-operative surgical planning, and meticulous perioperative monitoring, radical resection of the giant pheochromocytoma was safe and feasible with successful postoperative outcomes.

Supine mini percutaneous nephrolithotomy in horseshoe kidney.

OBJECTIVE: The percutaneous nephrolithotomy (PCNL) in Horseshoe kidneys (HSK) is usually performed in the prone position, allowing entry through the upper pole and providing good access to the collecting system. However, in patients with normal kidney anatomy, the supine position is reliable and safe in most cases, but it is unknown whether the supine position is adequate in patients with HSK. The purpose of this study was to describe the results of PCNL in HSK in three different surgical institutions and to evaluate the impact of supine position during surgery, comparing pre-operative and post-operative data, complications, and stone status after surgery. MATERIAL AND METHODS: Between 2017 and 2022, a total of 10 patients underwent percutaneous renal surgery for stone disease in HSK. All patients were evaluated pre- and post- operatively with non-contrast CT. we evaluated patients (age and gender), stones characteristics (size, number, side, site and density ), and outcomes. The change in haemoglobin, hematocrit, creatinine and eGFr were assessed between the most recent preoperative period and the first postoperative day. Procedure success was defined as stone-free or presence of ≤4 mm fragments (Clinically Insignificant residual Fragments - CIrF). Complications were registered and classified according to Clavien-dindo Grading System, during the 30 - day postoperative period and Clavien scores ≥ 3 were considered as major complications. Statistical analysis was performed using "r 4.2.1" software, with a 5% significance level. we also compared pre-operative and post-operative data using "wilcoxon signedrank test". RESULTS: No statistical difference was observed between preoperative and post-operative renal function data. At one post operative day CT scan, an overall success rate of 100% was registered. 9/10 patients were completely free from urolithiasis (stone-free rate: 90%), while 1/10 patients had ≤4 mm residual stone fragments (CIrF rate: 10%). No cases of intraoperative complications were registered. Post-operative complications were reported in 1/10 patients. A patient developed urosepsis (defined as SIrS with clinical signs of bacterial infections involving urogenital organs - Clavien-dindo Grade II) after procedure, and was treated with intravenous antibiotic therapy successfully.  Conclusions: This study shows that in patients with HSK mini- PCNL in supine position allows to achieve good stone free rate with a very low morbidity. According to our series, the described technique for PCNL in HSK should be an option. Nevertheless these results must be confirmed by further studies.

Imaging features of renal ectopia and fusion in 13 cats.

CASE SERIES SUMMARY: A retrospective multicenter case series of renal fusion anomalies in cats was investigated. The aim of this study was to describe the imaging characteristics (radiography, ultrasonography and CT) of renal ectopia and fusion in cats. A total of 13 feline patients (median age 9 years) were included in this multicentric retrospective study. Ultrasound was available in 12/13 cases, radiographs in 4/13 cases and CT in 3/13 cases. Of the 13 cases, seven were left to right fusions, four were right to left fusions, one was on the midline and one was in the pelvic inlet. Adopting a human classification system, there were five lump kidneys, four disc kidneys, one horseshoe kidney, one caudal ectopia, one L-shaped kidney and one pelvic kidney. In 2/13 cases, additional congenital malformations were noted, including an azygous continuation of the caudal vena cava and a peritoneal-pericardial diaphragmatic hernia. RELEVANCE AND NOVEL INFORMATION: This study provides further description of the imaging findings in feline patients with fused renal ectopia. The morphologic characteristics of the fused kidneys in cats appear similar to what is published in the human literature. Renal fusion might be an incidental finding in cats, but further investigations are necessary to determine their clinical relevance.

Bilateral Wilms tumor in a patient with a horseshoe and duplex kidney: A case report.

The occurrence of horseshoe kidney with duplex urinary collecting systems is rare. Herein, we report a case of bilateral Wilms tumor (BWT) in a patient with a concurrent horseshoe kidney and left duplex kidney, which had not been previously reported. The patient was treated with neoadjuvant chemotherapy, followed by surgical resection and adjuvant chemotherapy. The tumor recurred 6 months postoperatively. A second resection was performed, followed by the administration of chemotherapy and radiotherapy. The patient passed away 15 months after the initial diagnosis of BWT.

Wilms Tumor in Child With Trisomy 18 and Horseshoe Kidney.

Trisomy 18 is associated with several congenital malformations, including horseshoe kidney. It can be full, partial, or mosaic, and mosaicism is often associated with lesser severity and longer life expectancy, placing patients at greater risk of developing neoplasms or malignancies. One common tumor among children with Trisomy 18 is Wilms tumor, which is also associated with renal congenital abnormalities such as horseshoe kidney. We present a case describing the occurrence of these three characteristics: development of Wilms tumor in a patient with Trisomy 18 and a horseshoe kidney and discuss treatment with regards to these conditions.

Robot-assisted laparoscopic pyeloplasty is a valid option for ureteropelvic junction obstruction repair in adults with congenital renal abnormalities: a case series study.

BACKGROUND: Congenital renal anomalies are rare but may be associated with obstruction of the ureteropelvic junction. Given the rarity of simultaneous ureteropelvic junction obstruction [UPJO] and renal anomalies in the adult population, there is limited literature on approaching these patients. We report our experience with robotic assisted laparoscopic pyeloplasty for UPJO repair in this subset of patients. METHODS: Data on adult patients with simultaneous congenital renal abnormalities and UPJO who underwent robotic assisted laparoscopic pyeloplasty between 2008 and 2020 was reviewed. Pre-operative data, intraoperative parameters as well as post-operative data including symptom resolution and radiologic findings were recorded. RESULTS: Ten patients, 4 female and 6 males, with a mean age of 47 years were identified as having simultaneous congenital renal abnormalities and UPJO. Anomalies identified were horseshoe kidney in four patients, duplex kidney with obstruction of one moiety in two patients, malrotated kidney in two patients, and pelvic kidney in two patients. Eight out of ten were symptomatic at presentation with flank pain being the most common symptom. Eight patients underwent robotic pyeloplasty via the dismembered technique, while two underwent robotic Y-V pyeloplasty. With a mean follow up time of 13 months, 8/9 (88%) symptomatic patients enjoyed symptom resolution. Post-op renogram was available for nine patients and showed resolution of obstruction in all patients (100%). One patient developed a urine leak which was managed successfully with drainage. CONCLUSIONS: Robotic assisted laparoscopic pyeloplasty is a safe, feasible and effective surgical approach in management of adult patients with concomitant UPJO and renal anomalies.

Horseshoe Kidney: 500 Years From the First Report in the Literature.

Horseshoe kidney or ren arcuatus is the most common renal fusion anomaly, with an incidence of 1:500 in the normal population and a male predominance of 2:1. In >90% of cases, the fusion occurs along the inferior pole. It may vary in location, orientation, and arterial and venous anatomy. In 1522, Berengario da Carpi described this renal malformation for the first time in his masterpiece "Isagogae breves" (Introduction to Anatomy). He reported the results of a postmortem examination in the public autopsy room of the University of Bologna, describing "kidneys that are continuous as if they were a kidney, with two emulsifying veins, two emulsifying arteries, two ureteral outlets." In 1564, Leonardo Botallo described and illustrated the features of this atypical anatomical representation, and later, in 1602, Leonard Doldius added further details by examining this anatomical feature during an autopsy. In 1761, Giovanni Battista Morgagni discussed this condition not only as a rare anatomical curiosity found only in necroscopy but also discussed its physiological aspect. In the nineteenth century, with the advent of renal surgery, the horseshoe kidney played a more important role in urological diagnosis and treatment, and its identification became more frequent. With the advent of pyelography, imaging reports of the horseshoe kidney allowed a more accurate representation of the anatomical variants, which was particularly useful in preoperative assessment and outcomes. Berengario da Carpi laid the foundation for a better knowledge of this anatomical anomaly. Five hundred years after the first report in the literature, relevant advances have been made in the management of complications associated with horseshoe kidney and in diagnosis, confirming the need to monitor individuals with this condition who are at higher risk of developing chronic kidney disease.

Implications of Tumor Surgery in Horseshoe Kidneys: A Comparative Study of Outcomes and Surgical Practices.

OBJECTIVE: To contrast surgical outcomes of Horseshoe Kidney (HSK) patients with localized renal masses suspected of cancer with nonfused nonectopic kidney patients, emphasizing safe surgical practices for HSKs. METHODS: The study examined solid tumors from the Mayo Clinic Nephrectomy registry between 1971 and 2021. Each HSK case was matched to three non-HSK patients based on various factors. The outcomes measured included complications within 30days of surgery, change in estimated glomerular filtration rate, and overall, cancer-specific, and metastasis-free survival rates. RESULTS: Thirty of the 34 HSKs had malignant tumors compared with 90 of the 102 patients in the nonfused nonectopic referent cohort. Accessory isthmus arteries were present in 93% of HSK cases, with 43% exhibiting multiple arteries and 7% with 6 or more arteries. Estimated blood loss and surgery duration were significantly higher in HSKs (900 vs 300 mL, P = .004; 246 vs 163 minutes, P < .001, respectively). The HSK group demonstrated an overall complication rate of 26% (vs 17% in referents, P = .2) and a median change in estimated glomerular filtration rate at 3months of - 8.5 (vs -8.1 in referents, P = .8). At 5-year follow-up, survival rates for HSK patients were 72%, 91%, and 69% for overall, cancer-specific, and metastasis-free survival, respectively. The corresponding rates were 79%, 86%, and 77%, respectively, for matched referent patients (P > .05). CONCLUSION: HSK tumor management is technically challenging with higher blood loss; however, the data demonstrate comparable outcomes for patients with HSK tumors, including complications and survival, to those without HSKs in experienced centers.

The role of retrograde intrarenal surgery in kidney stones of upper urinary system anomalies.

INTRODUCTION: Fusion, pelvic, and duplicated urinary tract anomalies of the kidney are rarely seen. There might be some difficulties in the stone treatment, in the administration of extracorporeal shockwave lithotripsy (ESWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), and laparoscopic pyelolithotomy procedures in these patients due to the anatomical variations in kidneys with anomalies. AIM: To evaluate RIRS results on patients with upper urinary tract anomalies. MATERIALS AND METHODS: Data of 35 patients with horseshoe kidney, pelvic ectopic kidney, and double urinary system in two referral centers were reviewed retrospectively. Demographic data, stone characteristics, and postoperative characteristics of the patients were evaluated. RESULTS: The mean age of patients (n=35, 6 women and 29 men) was 50 years. Thirty-nine stones were detected. The total mean stone surface area in all anomaly groups was found to be 140 mm2, and the mean operative time was 54.7±24.7 minutes. The rate of using ureteral access sheath (UAS) was very low (5/35). Eight patients needed auxiliary treatment after the operation. The residual rate, which was 33.3% in the first 15 days, decreased to 22.6% in the third month follow-ups. Four patients had minor complications. In patients with horseshoe kidney and duplicated ureteral systems, it was observed that the risk factor increasing the presence of residual stones was the total stone volume. CONCLUSIONS: RIRS for kidneys with low and medium stone volume anomalies is an effective treatment method with high stone-free and low complication rates.

Retrograde intrarenal surgery for stones associated with renal anomalies: caliceal diverticulum, horseshoe kidney, medullary sponge kidney, megacalycosis, pelvic kidney, uretero-pelvic junction obstruction.

PURPOSE OF REVIEW: Nowadays, due to the increase of imaging diagnosis, we identify easily renal anomalies, and we can choose between a wide range of armamentarium to treat symptomatic stones in those challenging cases. However, there is a lack of evidence and consensus on its use. The aim of this narrative review is to collect all the available data about safety and efficacity of retrograde intrarenal surgery (RIRS) in the treatment of kidney stones associated to a renal anomaly. RECENT FINDINGS: Renal anomalies are uncommon findings and even more if it has to be associated with renal stones. After a literature review of the past 2 years, there are a small number of studies that compare the outcomes in patients who have been treated with minimally invasive modalities and they are mainly focus on RIRS. SUMMARY: It is of extreme importance to know the advances on the stone treatment in anomalous kidneys. With the development of new laser technologies, RIRS is becoming a more interesting technique with high success rate and safety. Further studies are needed to make an accurate statement about the adequate surgical technique for each renal anomaly and also, clinical trials using new laser technologies.

Nephron-sparing surgery for primary mucinous adenocarcinoma of renal pelvis in horseshoe kidney: A case report.

RATIONALE: Mucinous adenocarcinoma of the renal pelvis is extremely rare in malignancy of the renal pelvis, and <100 cases have been reported so far. However, horseshoe kidneys appear to be more prone to this mucinous gland metaplasia. Due to the lack of a specific diagnostic basis, it is difficult to confirm the diagnosis before surgery, which is easy to cause misdiagnosis. PATIENT CONCERNS: We report a 64-year-old male patient who found a cystic mass in the left kidney during physical examination. CT examination showed a horseshoe kidney with a cystic mass 9.5 × 8.0 cm in front of the left kidney, lacking obvious diagnostic features. DIAGNOSIS: It was misdiagnosed as cystic teratoma before the operation, and was diagnosed as mucinous adenocarcinoma of the renal pelvis through pathological examination after the operation. INTERVENTIONS: Resection of the tumor by nephron-sparing surgery and postoperative chemotherapy. OUTCOMES: No tumor recurrence was found at 6 years of follow-up. After 7 years, the patient had multiple metastases in the abdominal wall and peritoneum, and no tumor recurrence was found in the urinary system. The patient received chemotherapy again and survived well. LESSONS: The prognosis of nephron-sparing tumor resection for MRAP is not significantly different from that of radical nephroureterectomy + bladder cuff excision. Because it can reduce the risk that patients can not tolerate follow-up chemotherapy due to abnormal renal function after surgery, which may be more beneficial in patients with kidney abnormalities or chronic disease.

Horseshoe kidney: Morphologic features, embryologic and genetic etiologies, and surgical implications.

The horseshoe kidney (HSK) is the most common congenital abnormality of the upper urinary tract with an incidence of approximately 1 in 500 in the general population. Although individuals with HSK are often asymptomatic, they are at increased risk for neoplasms, infections, ureteropelvic obstruction secondary to lithiasis or vascular compression. Direct injury from trauma is increased in these individuals as is the risk of intraoperative complications secondary to damage involving the typically complex renal or adrenal vascular supply. We briefly review etiological factors including renal and urinary system embryology, genetic mutations, abnormalities related to faulty cell signaling, aberrant cell migration, and other possible causes including environmental exposures and trauma. In addition, we call attention to factors that might influence the success of surgical procedures in patients with HSK. We argue that an understanding of possible etiologies of the HSK and its different subtypes may be useful when planning surgical procedures or considering risk-benefit ratios associated with different surgical options. We briefly present the organization of a HSK in a 100-year-old male demonstrating an unusual vascular supply discovered during a dissection laboratory session in a medical school anatomy course. We describe the structure of the HSK, the position and relationships of the HSK to other structures within the abdomen, and the associated vascular relationships.