Periportal Plexiform Neurofibromatosis; a rare intra-abdominal manifestation of NF1.

Periportal Plexiform Neurofibromatosis (PPNF) is a rare visceral manifestation of Neurofibromatosis Type 1 (NF1) or Von Recklinghausen disease. Neurofibromas are the most common lesions in NF1. We present a case of a young female diagnosed with NF1 who initially presented with hard abdominal mass. Contrast enhanced CT revealed the unusual lintrahepatic periportal plexiform neurofibromatosis in addition to a typical large retroperitoneal lumbar neurofibroma.

The Role of Tc-99m DTPA Renal Dynamic Scintigraphy in Retroperitoneal Liposarcoma.

PURPOSE: Technetium-99m diethylene triamine pentaacetic acid (Tc-99m DTPA) renal dynamic scintigraphy is a widely used imaging technique that evaluates renal function of patients with extrarenal abnormalities, but its clinical value in potentially offering us information on proliferation of liposarcoma has not yet been reported. METHODS: We retrospectively reviewed 7 patients with histopathologically confirmed retroperitoneal liposarcoma who underwent Tc-99m DTPA renal dynamic scintigraphy. The clinical data, histopathological findings, Glomerular Filtration Rate (GFR), and Tc-99m DTPA uptake were recorded. RESULTS: Dedifferentiated liposarcoma and well-differentiated liposarcoma showed dissimilar degrees of Tc-99m DTPA uptake, an observation that correlated with Ki-67 expression (p < 0.01). 4 of the 7 patients were diagnosed with dedifferentiated liposarcoma, showing a moderate uptake of Tc-99m DTPA and greater than 20% Ki-67 expression on histological slides. Meanwhile, the remaining 3 patients, diagnosed with well-differentiated liposarcoma, showed no uptake of Tc-99m DTPA and Ki-67 expression of less than 5%. CONCLUSIONS: This study suggests that Tc-99m DTPA renal dynamic scintigraphy provides diagnostic value in patients with retroperitoneal liposarcoma, not only in evaluating renal function but also in visualizing lesion-related radionuclide uptake, which may potentially offer further clinical insights into tumor proliferation and provide prognostic value for clinical outcomes in patients with retroperitoneal liposarcoma.

Intrapelvic Retroperitoneal Synovial Sarcoma in a 15-Year-Old Adolescent Girl: A Case Report and Review of the Literature.

Synovial sarcomas are a rare subtype of soft tissue sarcomas mostly located in the lower extremities. The authors report a case of synovial sarcoma in a 15-year-old adolescent girl with several unusual features including age, intrapelvic retroperitoneal location of the primary tumor, and presentation with right abdominal tenderness and compression of the iliac vessels with thrombosis of the right iliac and femoral vein.

The natural history of incidental retroperitoneal schwannomas.

The natural history of asymptomatic retroperitoneal schwannomas is poorly understood. This study aimed at investigating the natural history of incidental retroperitoneal schwannomas. The medical charts and imaging studies of 22 asymptomatic patients under observation for at least 12 months for retroperitoneal schwannomas were reviewed. The duration of follow-up ranged between 13 and 176 months (mean 48 months). In the 22 patients managed by the "wait and see" approach, the average tumor size at initial presentation was 51 mm, which increased to 57 mm at final follow-up. During the final follow-up, 2 patients required surgical treatment for tumor enlargement, while the remaining patients remained asymptomatic without surgery. The average growth rate of the tumors was 1.9 mm/year (range: -1.9 to 8.7 mm/year). The majority of asymptomatic retroperitoneal schwannomas demonstrate minimal growth and may be suitable for management with the "wait and see" approach.

Surgical management of retroperitoneal schwannoma complicated with severe hydronephrosis: A case report.

RATIONALE: Schwannomas are usually benign tumors arising from well-differentiated schwann cells, which rarely occur in the retroperitoneal space. The lack of specific signs and radiologic imaging characteristics makes preoperative diagnosis rather difficult. Most retroperitoneal schwannomas are benign and the primary treatment choice for retroperitoneal schwannomas is surgical excision, however, the involvement of the urinary system is scarcely reported. PATIENT CONCERNS: A 34-year-old woman presented with progressive left abdominal pain and rebound abdominal mass at the left lower quadrant for 1 month. Radiological imaging suggested capsulated solid mass with cystic and necrotic areas in the retroperitoneum accompanied by severe left kidney hydronephrosis and preoperative biopsy result was inconclusive. DIAGNOSES: We believe this is a rare case of retroperitoneal schwannoma complicated with severe hydronephrosis. INTERVENTIONS: After preparation, the patient underwent laparoscopy exploration and converted to open surgical exploration. The patient accepted complete surgical excision of the retroperitoneal tumor and left kidney. Postoperative pathology diagnosis of the mass was proven to be benign retroperitoneal schwannoma. OUTCOMES: Postoperative course of the patient was uneventful and the left abdominal pain was greatly improved. After 12-month follow up, no evidence of recurrence or any other complication including renal failure was observed. LESSONS: Preoperative imaging and preoperative ultrasound-guided biopsy are helpful to make accurate diagnosis. The final diagnosis is based on postoperative histological and immunohistochemical findings. The primary treatment option is complete surgical resection of the retroperitoneal schwannoma and the involved upper urinary system when severe hydronephrosis occured. Local recurrence and overall survival are closely correlated with negative resection margins and pathology types.

Effect of nephrectomy for retroperitoneal sarcoma on post-operative renal function.

BACKGROUND AND OBJECTIVES: Surgical resection of retroperitoneal sarcomas (RPS) often involves removal of the ipsilateral kidney. We evaluated the long-term post-operative renal function in patients who underwent a nephrectomy as part of their en-bloc resection of RPS. METHODS: Retrospective review of an institutional database identified RPS patients who underwent nephrectomy for curative intent from 1990 to 2014. The primary outcome measured was chronic kidney disease (CKD) calculated by the glomerular filtration rate (GFR). RESULTS: Of the 47 patients in our study, 19 (40%), 18 (38%), and 10 (21%) patients had a preoperative CKD stage 1, 2, and 3, respectively. The GFR decreased by an average of 33.4 mL/min/1.73 m2 with 66% of patients demonstrating mild progression of their renal impairment. Only three (6%) patients progressed to CKD stage 4 or 5, one of which required life-long dialysis. CONCLUSION: Nephrectomy as part of an en-bloc resection is associated with a decrease in GFR that is not clinically significant. Fear of kidney failure should not prevent a surgeon from performing a nephrectomy in the treatment of RPS.

Difference in left renal vein pressure: an indicator for free of reconstruction after ligation in retroperitoneal tumor patients.

We hypothesized that the left renal vein pressure difference (ΔP) before and after the ligation can serve as an objective indicator for free of reconstruction after resection of a retroperitoneal tumor with renal segment of inferior vena cava and right kidney. After established a model of left renal vein compression, 45 miniature pigs were operated on experimental procedures including renal segment of inferior vena cava resection, right nephrectomy, and left renal vein ligation. The ΔPs of left renal vein before and after the ligation were measured. Safe ΔP variation without causing acute kidney injury was calculated using regression analysis. In human the safety range of ΔP before and after ligation of the left renal vein was calculated by diuretic response test. The safety range of ΔP in animals or human was 0-11.9 or 0-17.5 cm H2O, respectively. The renal function changed dramatically (p < 0.01), characterized by a significant increase in the rate of acute kidney injury when the ΔP was beyond the upper limit of the safety range. In conclusion, ΔP can predict free of reconstruction after resection of a retroperitoneal tumor with the renal segment of the inferior vena cava and the right kidney.

A paraganglioma in a hypertensive patient with unilateral renal hypoplasia.

We report the case of a 46-year-old hypertensive Japanese female with renal insufficiency related to unilateral renal hypoplasia. The patient was found to have developed paraganglioma in the retroperitoneal space over a 5-year period. Catecholamine-producing tumors are not usually recognized as conditions associated with renal hypoplasia. Our long-term observation of the patient eventually led us to the diagnosis of paraganglioma. In hypertensive patients with chronic kidney disease, not only the renin-angiotensin-aldosterone system but also catecholamine activity may be involved, particularly in the patients whose cases are complicated with unilateral renal hypoplasia.

Cyclic fluctuation of blood pressure in neonatal neuroblastoma.

Herein is described a case of neonatal neuroblastoma with cyclic blood pressure fluctuation and elevated catecholamines. The fluctuations stabilized after treatment with α-adrenergic blocker and the perioperative course was uneventful. The possibility of catecholamine-related symptoms including hypertension, heart failure, and blood pressure fluctuations should be considered in the treatment for neuroblastoma; if they are present, treatment with α-blockers is effective.

Long-term follow-up results of the observation program for neuroblastoma detected at 6-month mass screening.

We conducted an observation program of neuroblastoma in infants, detected by mass screening at 6 months of age; we followed up with them for 15 years. No recurrence was observed after disappearance of tumors, and persistent tumors showed no malignant transformation or metastasis. Histology of the resected tumors showed age-related differentiation.

Long term survival in a case of concurrent retroperitoneal liposarcoma and renal cell carcinoma: a case report.

BACKGROUND: Liposarcoma is one of the most common soft tissue sarcomas found in adults. It has a predilection for retroperitoneal space. Renal cell carcinoma is the most common tumor of the kidney. CASE PRESENTATION: Concurrent retroperitoneal liposarcoma and renal cell carcinoma were found in a 34-year-old Japanese man. The renal tumor was first detected by ultrasonography, it was confirmed by computed tomography, which also identified a presumptive retroperitoneal liposarcoma, and the tumors were further assessed with magnetic resonance imaging. The patient was treated by surgical resection of retroperitoneal liposarcoma and left nephrectomy and has been disease-free for 10 years. CONCLUSIONS: The concomitant occurrence of a renal tumor and a primary primary liposarcoma is rare. The major factors promoting a good prognosis in this case were the favorable histology and the small size of the tumors.

[A case of incidentally diagnosed retroperitoneal lymphangioleiomyomatosis with no respiratory symptoms].

A 39-year-old woman presented with a large retroperitoneal tumor found incidentally in a routine examination. The 138×37×26 mm mass was located in the left paraaortic region. Blood tests and urinalyses including endocrinological examinations revealed no abnormalities. A chest computed tomography revealed multiple thin-walled pulmonary cysts, which is a characteristic of lymphangioleiomyomatosis (LAM). Because the findings strongly suggested that the retroperitoneal tumor was an extrapulmonary manifestion of LAM, we performed laparoscopic resection of the tumor for diagnosis and treatment. The pathological diagnosis was LAM. The tumor cells were immunohistochemically positive for α -smooth muscle actin and weakly positive for HMB45, which is consistent with LAM. The cells were also positive for estrogen receptor (ER) and progesterone receptor (PgR). LAM is a rare progressive disease that affects mainly the lung, and leads to chronic respiratory failure. Extrapulmonary LAM without respiratory symptoms, is extremely rare. In the past, the prognosis of LAM was poor, with a median survival of 8-10 years, but now 85% survive more than 10 years. In the present case, deterioration of pulmonary lesions was not observed during the 10 months follow-up. Because ERand PgRfindings were positive, we will consider hormonal therapy as a treatment option, when the pulmonary lesions progress in the present case.

Lipossarcoma gigante de retroperitônio / Giant Retroperitoneal Liposarcoma / Liposarcoma Retroperitoneal Gigante

Introdução: Neoplasias mesenquimais, apesar de infrequentes, podem se apresentar como um desafio terapêutico quando atingem grandes proporções. O objetivo dos autores é descrever o caso de um lipossarcoma retroperitoneal que, devido a seu grande volume, apresentou peculiaridades em seu planejamento terapêutico, bem como revisar sua apresentação clínica, diagnóstico e tratamento. Relato do caso: Homem, 52 anos, consultou com queixa de aumento da circunferência e volumosa massa abdominal palpável. Tomografia computadorizada e ressonância magnética do abdômen revelaramgrande lesão expansiva no retroperitônio, com deslocamento de diversas vísceras intra-abdominais, sugestiva de volumoso tumor maligno de origem retroperitoneal. O paciente foi submetido à laparotomia com ressecção da massa em conjunto com o rim direito. O exame anatomopatológico revelou tratar-se de lipossarcoma desdiferenciado medindo 62 cm nomaior diâmetro, com peso de 19 kg. Foi indicado tratamento complementar com radioterapia. Houve excelente evoluçãopós-operatória, estando o paciente assintomático 36 meses após o procedimento. Conclusão: Os lipossarcomas do retroperitônio são uma entidade clínica rara, com apresentação clínica variável conforme sua localização, tipo histológico, grau de malignidade e tamanho. A única possibilidade de cura ainda é a ressecção cirúrgica radical com margens livres. Desde que o paciente apresente boas condições clínicas de tolerar o procedimento, o tamanho volumoso do tumor não é necessariamente uma contraindicação ao tratamento cirúrgico.

Hemangiopericitoma retroperitoneal / Retroperitoneal hemangiopericytoma

El hemangiopericitoma es un tumor infrecuente de origen vascular que deriva de los pericitos de Zimmerman. Representa aproximadamente un 1% de todos los tumores vasculares. En el momento del diagnóstico, establecer el potencial de malignidad de este tipo de tumoración es algo habitualmente controvertido. El pronóstico se basará en el patrón histológico y en la evolución clínica, siendo la aparición de recurrencias locales o de metástasis a distancia los únicos signos definitivos de malignidad. El caso de un paciente de 61 años con un hemangioperictoma retroperitoneal de gran tamaño nos sirve para revisar los aspectos clínicos y patológicos, el tratamiento y los factores pronósticos de esta rara neoplasia (AU)

Hemangiopericytoma is a rare tumour of vascular origin derived from Zimmermann's pericytes. It represents approximately 1% of all vascular tumours. At the time of diagnosis, determining the malignant potential of this type of mass is usually controversial. Prognosis will be based on histological patterns and the clinical course, with the appearance of local recurrences or distant metastases being the only definitive signs of malignancy. The case of a 61 year old patient with a very large retroperitoneal hemangiopericytoma serves to review clinical and pathological aspects, treatment and prognostic factors of this rare neoplasm (AU)