[Small pelvis lipoma spreading to the gluteal region]. / Lipoma malogo taza i yagodichnoi oblasti.

We present a 36-year-old woman with small pelvis lipoma spreading to the gluteal region through the greater sciatic foramen. Resection of lipoma was performed via two accesses (lower median laparotomy and semilunar incision in the gluteal region). The tumor was the content of sciatic hernia that is extremely rare. Combination of surgical approaches can provide favorable outcomes in these patients.

Large retroperitoneal extraskeletal Ewing's sarcoma with renal pedicle invasion: a case report.

BACKGROUND: Extraskeletal Ewing's sarcoma (EES) is a rare malignant tumor primarily found in children and young adults. Localized disease can present with nonspecific symptoms such as local mass, regional pain, and increased skin temperature. More severe cases may present with systemic symptoms such as malaise, weakness, fever, anemia, and weight loss. Among these lesions, retroperitoneal sarcomas are relatively uncommon and difficult to diagnose. Since they are usually asymptomatic until large enough to compress or invade the surrounding tissues, most are already advanced at first detection. Traditionally, the treatment of choice is complete surgical resection, sometimes combined with postoperative radiotherapy and chemotherapy. We report a case of EES with left renal artery invasion in the left retroperitoneal cavity successfully treated with transarterial embolization and surgery. CASE PRESENTATION: A 57-year-old woman with a negative family history of cancer presented at our Urology Department with a large left retroperitoneal tumor found by magnetic resonance imaging during the health exam. Physical examination showed a soft abdomen and no palpable mass or tenderness. Imaging studies showed that the tumor covered the entire left renal pedicle, but the left kidney, left adrenal gland, and pancreas appeared tumor free. Since the tumor tightly covered the entire renal pedicle, tumor excision with radical nephrectomy was advised. The patient underwent transarterial embolization of the left renal artery with 10 mg of Gelfoam pieces daily before surgical excision. Tumor excision and left radical nephrectomy were uneventful the day after embolization. Post-operatively, the patient recovered well and was discharged on day 10. The final histopathological analysis showed a round blue cell tumor consistent with an Ewing sarcoma, and the surgical margins were tumor free. CONCLUSIONS: Retroperitoneal malignancies are rare but usually severe conditions. Our case report showed that retroperitoneal EES with renal artery invasion could be treated safely with transarterial embolization and surgery.

A rare case of primary retroperitoneal extraovarian granulosa cell tumor.

Extraovarian granulosa cell tumors (GCTs) are rare neoplasms. They arise from the ectopic gonadal tissue along the embryonal route of genital ridge. We present a case of an extraovarian tumor in an elderly female who presented with lump in the abdomen occupying the pelvic region. She was operated and the mass was excised with intact capsule. Histopathology revealed the mass to be an adult granulosa cell tumor. Extraovarian granulosa cell tumors are very rare with only 13 such cases reported in literature to date. The present case is the largest primary retroperitoneal adult granulosa cell tumor reported till date.

[Diagnosis and surgical treatment of a patient with Castleman disease]. / Diagnostika i khirurgicheskoe lechenie patsienta s bolezn'yu Kastlemana: klinicheskoe nablyudenie.

Castleman disease (CD) is a benign lymphoproliferative disease. Small prevalence and diverse clinical course of disease makes it difficult to standardize diagnostics and treatment. Currently, the number of CD patients has increased with improvement in the quality of examination. Therefore, differential diagnosis of this disease is important. We present a young patient with CD and retroperitoneal non-organ neoplasm. Despite a thorough preoperative examination, the final diagnosis was established only after histological examination of surgical specimen. We discuss the diagnosis and surgical treatment of a patient with unicentric type of CD.

Bloom where you are planted: Hemangioma or malignancy?

Vascular anomalies comprise a spectrum of disorders characterized by the abnormal development or growth of blood and lymphatic vessels. These growths have unique features and diverse behaviors, mandating a multidisciplinary approach in their evaluation, diagnosis, and management. Here we describe the case of a male toddler presenting with an abdominal mass, originally treated as a metastatic retroperitoneal tumor, but subsequently felt to represent a vascular anomaly.

Lipoma or Liposarcoma? Robotic Resection of a Retroperitoneal Mass.

This video demonstrates a robotic excision of a large retroperitoneal lipomatous mass in a 48-year-old female with a known fibroid uterus. Computed tomography was performed for nephrolithiasis, and an incidental 7-cm fatty prominence in the right hemipelvis was found. Retroperitoneal tumours like benign lipomas and low-grade liposarcoma are difficult to differentiate. The latter has a high rate of local recurrence if incompletely resected; therefore, complete resection should be the goal of surgery. The patient underwent robotic-assisted laparoscopy that revealed a large lipomatous mass in the right retroperitoneal space consistent with radiographic imaging. The lipomatous tumour was carefully dissected and resected from the pararectal space without complication. Pathology revealed partially encapsulated, mature adipose tissue consistent with lipoma with negative fluorescent in situ hybridization (FISH) analysis using a dual-colour MDM2/CEN12 probe set, confirming the likely benign behaviour of the mass. Retroperitoneal lipomatous tumours are rare. Distinguishing between lipomas and liposarcomas is a diagnostic challenge both radiographically and intraoperatively. Confirmatory histopathology and, often, molecular pathology is necessary for the final diagnosis. Knowledge of the differing pathology and disease processes of retroperitoneal lipomatous masses, related surgical anatomy, careful surgical technique, and goals for complete excision are imperative for optimal management.

A large retroperitoneal lipoblastoma as an incidental finding: a case report.

BACKGROUND: Lipoblastoma is a rare benign mesenchymal neoplasm of infancy that most commonly occurs on the extremities and trunk but can arise at variable sites of the body. Retroperitoneal lipoblastomas are particularly rare but can grow to enormous size, and preoperative diagnosis is difficult with diverse, mostly malignant differential diagnoses that would lead to aggressive therapy. Since lipoblastoma is a benign tumor that has an excellent prognosis after resection, correct diagnosis is crucial. CASE PRESENTATION: A case of a large retroperitoneal tumor of a 24-month old infant that was clinically suspicious of a malignant tumor is presented. Due to proximity to the right kidney, clinically most probably a nephroblastoma or clear cell sarcoma of the kidney was suspected. Radiological findings were ambiguous. Therefore, the mass was biopsied, and histology revealed an adipocytic lesion. Although mostly composed of mature adipocytes, in view of the age of the patient, the differential diagnosis of a (maturing) lipoblastoma was raised, which was supported by molecular analysis demonstrating a HAS2-PLAG1 fusion. The tumor was completely resected, and further histopathological workup led to the final diagnosis of a 13 cm large retroperitoneal maturing lipoblastoma. The child recovered promptly from surgery and showed no evidence of recurrence so far. CONCLUSION: Although rare, lipoblastoma should be included in the differential diagnoses of retroperitoneal tumors in infants and children, and molecular diagnostic approaches could be a helpful diagnostic adjunct in challenging cases.

Clinical experience with the treatment of retroperitoneal vascular leiomyosarcoma originating from large veins.

BACKGROUND: Retroperitoneal vascular leiomyosarcoma (RVLMS) is an extremely rare disease in clinical practice, and it has poor prognosis. This article is to explore the diagnosis and treatment of RVLMS and present our experience. METHODS: Data of RVLMS patients were continuously collected in our hospital from August 2018 to February 2020: two males and two females with a median age of 56 (min-max = 33-61) years were included. Patients in whom paraganglioma could not be excluded were asked to take phenoxybenzamine before surgery. A multi-disciplinary team (MDT) meeting had been held and surgery was recommended. The operation procedures varied based on the tumor location, shape, and stage, and the core steps were "exposure of the retroperitoneum and tumor, identification of vital blood vessels, blocking the bloodstream, complete removal of the tumor and tumor thrombus, and release of blood flow". A Satinsky clamp was used to partially block the blood vessels. Follow-up was conveyed by revisits and phone calls. RESULTS: One patient underwent open surgery, and three patients underwent laparoscopic surgery, one of whom underwent conversion to open surgery. The procedures were finished successfully, with a median operative time of 314.5 (min-max = 224-467) mins. The median amount of intraoperative bleeding was 550 (min-max = 200-1500) ml, and three patients had transfusion during the operation. The mass was irregular in shape, with a median maximum size of 7.45 (min-max = 4.2-10.7) cm, and the pathological examination confirmed RVLMS, which has spindle-shape, high mitotic activity and atypia. One week after the operation, the median serum creatinine level was 85 (min-max = 70-99) µmol/L. The median follow-up time was 16 (min-max = 13-21) months, and 1 case reported asymptomatic recurrence. CONCLUSION: Uncharacteristic manifestations and imaging features contribute to the problematic diagnosis of RVLMS. Comprehensive preoperative evaluation and careful surgical planning are essential. Multicenter research is needed in the future to reach a dominant consensus.

Primary retroperitoneal mucinous cystadenocarcinoma in pregnancy - case report.

INTRODUCTION: Primary retroperitoneal mucinous cystadenoma (PRMC) and its malignant variant - cystadenocarcinoma are extremely rare tumors known only from case studies and reviews. PRMC is a cystic tumor of the retroperitoneum, which remains asymptomatic for a long time and can reach significant proportions. It occurs mainly in women. CASE REPORT: We present the case of a 38-year-old healthy woman with diagnosed resistance in the right mesogastrium during a c-section. The delivery was terminated without a surgical intervention. The above mentioned resistance was examined further by ultrasound, computed tomography and magnetic resonance imaging. All imaging examinations showed a solid - cystic bilocular expansion, which looked like a mesenteric cyst in the right paracolic area. The patient was asymptomatic at all times, with only a palpable resistance of the abdominal wall. In November 2020, the patient underwent an elective surgery - extirpation of the cystic tumor and prophylactic appendectomy. The operation was performed classically, via midline laparotomy without perioperative perforation of the cystic tumor and without complications in the postoperative period. The histopathological examination showed a malignant variant of PRMC. So far, the patient remains free of any problems and is followed at the department of oncology. CONCLUSION: The goal of treatment is to achieve complete surgical removal of the tumor without its perioperative perforation. Due to the rare occurrence of the disease, there are no guidelines for the diagnosis and treatment of PRMC. Precisely because PRMC is a rare tumor, it should be part of the differential diagnosis of cystic tumors of the retroperitoneum, especially when young women are concerned.

Gigantic intra-abdominal tumors the experience of one center.

A complex review of surgery treatment of unusually giant intra-abdominal and retroperitoneal tumors regardless of their origin and histological findings. The therapy of such neoplasms requires a multidisciplinary approach which is necessary to make a reasonable and responsible decision concerning not only the indication of surgery, but also its extent. The authors describe 5 case reports, highlighting specific aspects and pitfalls of the diagnosis and treatment of these rare cases.

Robotic resection for benign primary retroperitoneal tumors via the transperitoneal approach.

BACKGROUND: Surgical resection is the primary treatment for benign primary retroperitoneal tumors. However, only a few studies have reported robotic resection for retroperitoneal tumors due to the low morbidity rate, and only a small fraction of retroperitoneal tumors are eligible for minimally invasive operations. METHODS: A retrospective study enrolling 16 patients with benign primary retroperitoneal tumors between November 2016 and April 2020 was conducted to evaluate the efficacy of robotic resection for benign primary retroperitoneal tumors via the transperitoneal approach. Surgical skills were described in detail and operative experiences were summarized. RESULTS: The operations were uneventfully performed without conversion in all the patients. The median operation time was 135 (120-180) min, and the median estimated blood loss was 25 (20-60) mL. The median duration of diet restoration was 2 (1-2) days and the median length of postoperative hospital stay was 6 (4-7) days. No serious intraoperative or postoperative complications occurred during the perioperative period. CONCLUSIONS: Robotic resection via the transperitoneal approach is a feasible and safe procedure for highly selected patients with benign primary retroperitoneal tumors, with few postoperative complications and a rapid recovery.

First Report of Retroperitoneal Mucinous Cystadenoma in a Patient with Hirsutism.

Primary retroperitoneal mucinous cystadenomas (PRMC) are rare benign neoplasms with only 55 documented cases in the English literature so far. A 19-year-old female exhibited hirsutism and was found to have a cystic mass measuring 5.8 cm × 3.9 cm × 5.8 cm in the left retroperitoneum. During subsequent work up, a high pre-operative value of dehydroepiandrosterone sulfate (DHEA-S) was noted. The patient was referred to surgical oncology and underwent an uneventful laparoscopic cystectomy. Pathology classified the cyst as PRMC. Post-operatively, the patient's DHEA-S levels normalized, though there was no appreciable decrease in the patient's hirsutism in the short-term follow-up. The origin of PRMC is uncertain. Due to their unknown biological potential, surgical resection is usually recommended. To the best of our knowledge, this is the first report documenting a PRMC and elevated levels of androgens in conjunction with hirsutism.

Evaluation of clinical application of multi-slice computerized tomography in primary retroperitoneal tumors.

BACKGROUND: To accurately identify primary retroperitoneal tumors by multi-slice spiral CT (MSCT) for better treatment. MATERIALS AND METHODS: The common types of 380 cases of primary retroperitoneal tumor, lesion sites, and MSCT features were compared with pathological results. Fisher's or chi-square test approaches have been applied in this study. RESULTS: Multi-slice computerized tomography multi-directional reconstruction has a high accuracy for primary retroperitoneal tumors (95.7%). Seventy-three liposarcoma cases were located in peri-renal space, accounting for 76.8% (13/95) of the tumors in this region. Meanwhile, 65 cases of neurogenic tumors were located in the paravertebral column, accounting for 90.3% (65/72) of the tumors in this region. MSCT examination could effectively distinguish benign from malignant of primary retroperitoneal tumor (sensitivity = 87.2%, specificity = 82.7%, accuracy rate = 84.5%). Malignant tumors showed more irregularity shape than benign tumor (χ2  = 20.468, P < .001). 82.7% (191/231) of the malignant tumors showed adhesion or even invasion of surrounding tissues and organs (χ2  = 23.262, P < .001). Fat density of the lipoma is uniform, and lesion is not enhanced. Liposarcoma can be seen in varying proportions of fat and soft tissue density. CONCLUSION: The accuracy of MSCT scan for retroperitoneal tumors is high. Meanwhile, the coincidence rate of qualitative diagnosis before operation and/or before biopsy is also high.

Retroperitoneal tumors: Review of diagnosis and management.

Retroperitoneal tumors are extremely rare tumors occurring in the retroperitoneum. Retroperitoneal tumors are divided into benign tumors and malignant tumors, including retroperitoneal sarcoma. Approximately 70-80% of primary retroperitoneal soft-tissue tumors are malignant; however, these only account for 0.1-0.2% of all malignancies. Retroperitoneal sarcoma is an orphan malignant disease with a low incidence. The information on benign retroperitoneal tumors is limited. The American Joint Committee on Cancer/TNM classification updated to the 8th edition in 2017. In 2010, three new drugs for soft tissue sarcoma were approved based on the results of phase III trials, but the histological subtypes of the patients enrolled in the trials of each drug differed. Recently, in addition to surgery for retroperitoneal sarcoma, the effectiveness of perioperative radiation therapy has become interesting. For malignant retroperitoneal tumors and retroperitoneal sarcoma, survival improvement and locoregional recurrence prevention can be undertaken by carrying out surgery to secure negative margins with wide and combined resection of some adjacent organs, and cooperation with a trained medical team comprising of radiologists, pathologists and medical oncologists in centralized hospitals. Some clinical trials aimed at further improving treatment results by adding preoperative chemotherapy and radiation therapy based on histological confirmation using a correct needle biopsy are in progress. In recent years, molecular profiling has been used to select eligible patients for chemotherapy. In the future, precision medicine with next-generation sequencing technology will be expected among the diverse and potential future treatments for retroperitoneal sarcoma. In this review, we summarized the current state of retroperitoneal tumors and retroperitoneal sarcoma.

Successful emergency endovascular aortic repair for intratumoral hemorrhage in extensive retroperitoneal mass of testicular origin.

BACKGROUND: Metastatic germ cell cancer of the testis is characterized by favorable prognosis since effective treatment methods are available even in cases of extensive disease. Retroperitoneal masses frequently encroach major blood vessels requiring a vascular intervention usually performed in association with the post-chemotherapy retroperitoneal lymph node dissection (RPLND). Reported clinical case describes a successful pre-treatment endovascular surgery for abdominal aortic rupture allowing for full-dose systemic chemotherapy administration, and subsequent radical surgical intervention at primary tumor site as well as metastatic retroperitoneal lymph node dissection including the reconstruction of inferior caval vein. CASE PRESENTATION: Patient presented with left-sided testicular tumor and voluminous retroperitoneal mass with vascular involvement. Soon after the patient had been admitted for the first cycle of cisplatin-based chemotherapy, computed tomographic angiography (CTA) revealed a dorsal aortic wall rupture with active extravasation and irregular pseudoaneurysmatic dilatation of the aorta below the leak area. Retroperitoneal intratumoral hemorrhage associated with the bilateral iliac venous thrombosis required an endovascular repair procedure of infrarenal abdominal aorta. CONCLUSIONS: Following the successful endovascular aortic repair 3 cycles of BEP (bleomycin, etoposide, cisplatin) regimen were administered with subsequent delayed left radical orchiectomy and RPLND associated with vena cava inferior (VCI) resection. Reconstruction of VCI was originally not deemed necessary as collateral blood flow appeared sufficient, however, intraoperative complications resulted in the need for unilateral VCI reconstruction, using the interposed bypass between right common iliac vein and infrarenal segment of VCI. Histopathologic examination of the attained specimen detected no vital cancer structures. The patient remains disease-free 18 months after the RPLND.

Three-dimensional printing - Assisted planning for complete and safe resection of retroperitoneal tumor.

BACKGROUND: Surgery is usually recommended to treat retroperitoneal tumors. However, complete surgical resections often remain challenging. OBJECTIVE: To assess the assistant role of three-dimensional (3D) imaging and printing model in retroperitoneal tumor resection, as well as compare the difference between 3D printing and computed tomography (CT) in preoperative planning and confidence building. METHODS: We admitted a patient with retroperitoneal mass (13.0×6.4×14.8 cm) adjacent to important abdominal blood vessels whose surgery was thought to be difficult. 3D printing and CT was arranged. A novel questionnaire and scoring system consisting of surgery difficulty and safety were designed to compare doctors understanding and confidence for surgery based on 3D printing and CT. Twenty-four doctors completed the scoring table based on CT and then 3D imaging, respectively. Paired t-test was applied for statistics analysis. RESULTS: Preoperative evaluation based on 3D printing indicated that the tumor could be removed completely. The operation lasted 120 minutes to successfully remove the tumor and the estimated blood loss was less than 100 ml. Scores based on 3D printing is significantly higher than CT in difficulty and safety of surgery (p < 0.001). Interestingly, the junior doctors seem to benefit more from 3D printing than the senior doctors. CONCLUSIONS: 3D imaging and printing model provides greater help for preoperative planning and confidence building than using CT in resection of retroperitoneal tumor, especially for the junior doctors.

The diagnostic utility of retroperitoneoscopic tissue biopsy for unresectable retroperitoneal lesions excluding urogenital cancers.

BACKGROUND: Retroperitoneal tumors are an uncommon disease known to consist of a diverse group of benign and malignant neoplasms. Treatment of unresectable retroperitoneal lesions requires pathological diagnosis. Here, we report the utility and safety of retroperitoneoscopic biopsy for unresectable retroperitoneal lesions excluding urogenital cancers. METHODS: We analyzed 47 patients consisting of 23 (49%) and 24 (51%) cases that underwent retroperitoneoscopic tissue biopsy and open biopsy, respectively. The clinicopathological features, including postoperative complications, were compared between the two groups. RESULTS: Tumor pathology was diagnosed successfully with a single operation in all patients. Malignant pathology (68%) was more common than benign pathology (32%). The most common pathology was malignant lymphoma, which accounted for about 50% of all cases. There was no significant difference with respect to the age, sex, tumor size, presence of tumor-related symptom, histopathology, operative time, and complications. Three (13%) of 23 patients in the retroperitoneoscopic biopsy group received percutaneous needle biopsy before laparoscopic excisional biopsy because the evaluation of needle cores failed to confirm subclasses of diagnosed pathologies. One patient was converted to open surgery just after the initiation of operation due to severe adhesion of adjacent structures. We had two cases with iatrogenic urinoma due to ureteral injury after retroperitoneoscopic biopsy. CONCLUSIONS: We conclude that retroperitoneoscopic biopsy is a safe and useful tool for benign and malignant retroperitoneal lesions, in comparison to open biopsy. It is critical to carefully examine the preoperative imaging for the location of tumors, especially those close to the renal pelvis and ureter.

Giant multilocular prostatic cystadenoma.

BACKGROUND: The giant multilocular prostatic cystadenoma is a very rare benign tumor of the prostate gland. It is composed of predominantly cystic enlarged prostatic glands in a fibrous stroma and spreads extensively into the pelvis. Because of the large size at the time of diagnosis, it is not always possible to determine the exact point of origin for these multilocular cystic neoplasms. Thus, diagnosis before histological examination of a surgical specimen is often difficult. Here, we present a case involving one of the largest giant multilocular prostatic cystadenomas reported in the literature and discuss preoperative diagnoses and appropriate surgical approaches for this rare retroperitoneal tumor. CASE PRESENTATION: A 50-year-old man presented with a 2-year history of abdominal distension and lower urinary symptoms. Enhanced CT showed a large retroperitoneal mass with multiple septations in the pelvis and lower abdomen, measuring 30 cm in size, surrounding the rectum and displacing the bladder, prostate, and seminal vesicle to the right anterior side. MRI showed multiple cysts with a simple fluid appearance on T2-weighted images and enhanced solid components on gadolinium-enhanced fat-saturated T1-weighted images, suggesting the retroperitoneal mass as leiomyoma with cystic degeneration or perivascular epithelioid cell tumor. Biopsy of the mass showed a spindle cell tumor with focal smooth muscle differentiation. Differential diagnosis comprising leiomyoma, low-grade leiomyosarcoma, and perivascular epithelioid cell tumor was made. Complete resection of the tumor with low anterior resection of the rectum was performed. The tumor was solid with multilocular cavities containing blackish-brown fluid and measured 33 × 23 × 10 cm. Histologically, the tumor was composed of variously sized dilated glandular structures lined by prostatic epithelia surrounded by fibromuscular stroma. The prostatic nature of the lesions was confirmed by immunohistochemical staining of the epithelium for prostate-specific antigen. Thus, pathological diagnosis was a giant multilocular prostatic cystadenoma. CONCLUSIONS: We present our experiences with one of the largest giant multilocular prostatic cystadenomas. When a retroperitoneal huge lesion with locular cavities fills the pelvis in a male patient, the possibility of giant multilocular prostatic cystadenoma should be considered before planning for retroperitoneal tumor treatment.

Challenging Diagnosis of a Solitary Retroperitoneal Mass: A Case Report of Castleman's Disease and Review of the Literature.

Castleman's disease (CD) is an uncommon type of lymphoproliferative disorder. Its etiology and prevalence are unclear. The retroperitoneum is a very rare site for presentation of the unicentric variant, where it mimics malignant tumors. A 59-year-old man is referred to the urology outpatient clinic for the study of microhematuria found in a routine analysis. CT scan of the abdomen identified a solid, circumscribed mass, measuring 28 × 30 × 31 mm in the left para-aortic zone, with homogeneous contrast enhancement. Excisional surgery and regional lymphadenectomy were performed via laparoscopy. Postoperative course concurred without incidences. Histological diagnosis confirmed unicentric CD, hyaline-vascular type. CD is a rare entity, and the unicentric type presents as an asymptomatic mass. Retroperitoneum is a rare localization, where initial imaging diagnosis is unclear and surgical resection is the preferred treatment.

A case report and a literature review of primary retroperitoneal mucinous cystadenoma: the importance of imaging in diagnosis and management.

Primary retroperitoneal mucinous cystadenoma (PRMC) is an extremely rare tumor: its histogenesis and its biological behavior remain speculative. Since most retroperitoneal tumors are malignant, a preoperative diagnosis of benignity is essential and it can be reached through imaging examinations, allowing a conservative management approach. We describe the case of a 52-year-old woman with abdominal pain and a palpable mass. Computed tomography of the abdomen revealed a retroperitoneal cystic mass, which was resected successfully through laparoscopy and diagnosed as PRMC. Although there are no pathognomonic, clinical or radiological findings for PRMC, it should be included in the list of differential diagnoses and its imaging criteria of benignity should always be sought, with the aim to exclude malignant tumors.