First report of retroperitoneal rhabdomyosarcoma treated with space-making particle therapy for preservation of renal function.

Space-making particle therapy, which consists of surgical placement of a spacer followed by particle therapy, has become a solution to the problem of normal organs being exposed to a high radiation dose. A bioabsorbable spacer is particularly suitable for this purpose, but is not widely used. Surgical placement of a spacer is performed mostly to protect the digestive tract, but can also be used to protect the kidneys. Therefore, we have been interested in the use of space-making particle therapy to preserve renal function. A 14 month-old boy with intermediate-risk retroperitoneal rhabdomyosarcoma underwent surgery with placement of a bioabsorbable spacer following neoadjuvant chemotherapy and then received proton beam therapy of 41.4 Gy (relative biological effectiveness) in 23 fractions. In the 41 months since PBT, he has survived without local recurrence or signs of renal impairment. This report describes the first-ever case of surgical placement of a bioabsorbable spacer with the aim of preserving renal function during proton beam therapy. Space-making particle therapy is an innovative solution for peritoneal tumors adjacent to the kidneys.

Primary Retrovesical Leiomyosarcoma: A Case Report.

Soft tissue sarcomas (STS) are a rare group of malignant tumors in adults. This group of tumors contains a variety of subtypes, each with distinct clinical features and presentations. Leiomyosarcoma is among the most common subtypes, which typically occur within the uterus, retroperitoneum, abdomen, and large blood vessels. At presentation, tumors are often large and may have metastasized to the lungs, liver, or peritoneum. Given the rarity and variability of the disease, a multidisciplinary treatment approach is essential for management, however, further research is needed to develop histologic-specific guidelines and targeted treatments. Here, we present a case of a 69-year-old male who was found to have a large pelvic mass of unknown etiology after presenting to the emergency department with generalized weakness, decreased appetite, and an inability to ambulate. On examination, he was found to have testicular swelling and trace edema of bilateral lower extremities. Labs significant for lactic acidosis and CT chest/abdomen/pelvis showed a large heterogeneously enhancing mass within the pelvis measuring up to 15 cm x 12 cm x 15 cm, of uncertain origin, but highly concerning for malignancy. Biopsy with immunohistochemical stains of the mass revealed a grade 2 leiomyosarcoma. Due to the size and location of the mass, transfer to a tertiary care center was recommended. Computed tomography angiography (CTA) abdomen/pelvis and magnetic resonance imaging (MRI) abdomen/pelvis performed at the tertiary care hospital revealed a 16.6 cm heterogeneously enhancing, necrotic mass within the retrovesical pelvic space and three liver lesions, which were concerning for metastases. Due to the patient's deconditioning and poor functional status, surgical resection and radiation were not offered. The patient expired soon after his code status was changed to comfort care.

Long-standing retroperitoneal schwannoma in a 36-year-old female: A case report.

INTRODUCTION: Schwannomas are encapsulated nerve sheath tumors derived from Schwann cells, primarily found in the head, neck, and extremities. Retroperitoneal schwannomas are rare and typically asymptomatic. CASE PRESENTATION: A 36-year-old female presented with a long-standing, asymptomatic right lower abdominal mass. Imaging revealed a retroperitoneal cystic mass displacing adjacent structures. The tumor was surgically excised, and histopathology confirmed the diagnosis of schwannoma. The patient had an uneventful postoperative recovery and remains symptom-free with no signs of recurrence. DISCUSSION: Schwannomas are benign nerve tumors primarily affecting women aged 30 to 50. This case involved an asymptomatic retroperitoneal schwannoma displacing the inferior vena cava without neurological symptoms. Imaging methods like ultrasound and CT are useful but often lack definitive results, and preoperative biopsy is not recommended due to risks of vascular injury. While conservative management may be suitable for asymptomatic cases, complete surgical excision is crucial to prevent recurrence. Although some suggest partial excision, most literature supports curative resection with negative margins, as incomplete removal can lead to a 10-20 % recurrence rate. The patient underwent successful complete resection. CONCLUSION: Retroperitoneal schwannomas are rare tumors that are difficult to diagnose preoperatively. Radiologic findings are usually nondiagnostic. The treatment of choice is complete surgical excision.

Sexual effects and long-term outcomes of endoscopic lumbar sympathectomy for plantar hyperhidrosis in men: a cross-sectional study.

Background: Plantar hyperhidrosis (PHH) is a disease with high psychosocial impact, and endoscopic lumbar sympathectomy (ELS) has been shown to be the best choice for treatment, but with some concerns such as compensatory sweating (CS) and sexual effects (SE), particularly in men. Objectives: The aim of this study is to evaluate the long-term effectiveness of ELS for controlling PHH in men, its side effects, and perceived sexual modifications. Methods: A cross-sectional study including only male patients operated for PHH with ELS between 2014-2022 at a private practice. During remote interviews, patients were asked about symptoms before and after ELS and about the postoperative effects on PHH. They were also objectively asked about any SE during the postoperative period. Validated quality of life for hyperhidrosis and erectile function questionnaires were also administered. Results: 10 male patients averaging 4.26±2.86 years post-ELS were interviewed. Eight of them (80%) achieved complete response (≥80% of sweat reduction) in the first month after surgery and this response was maintained up to the interview date. Two patients had partial response. In six patients, CS occurred, with 5 reporting it as non-troublesome. Six patients reported some type of SE, but none reported erectile dysfunction. Regarding the functional results, all patients rated ELS from good (10%) to very good (30%) or excellent (60%). Conclusions: Endoscopic lumbar sympathectomy was effective for treatment of plantar hyperhidrosis in these patients, improving their quality of life and providing lasting PHH control, with some transient sexual dysfunctions that did not impair their sexual life.

Contexto: A hiperidrose plantar (HHP) é uma doença de alto impacto psicossocial, e a simpatectomia lombar endoscópica (SLE) tem se mostrado a melhor escolha de tratamento. Porém, há algumas preocupações como suor compensatório (SC) e efeitos sexuais (ES), particularmente em homens. Objetivos: O objetivo deste estudo foi avaliar a eficácia a longo prazo da SLE para controlar a HHP em homens, seus efeitos colaterais e as modificações sexuais percebidas. Métodos: Tratou-se de um estudo transversal incluindo apenas pacientes do sexo masculino operados de HHP por meio de SLE entre 2014 e 2022 em consultório particular. Por meio de entrevistas remotas, os pacientes foram questionados sobre os sintomas antes e depois da SLE e sobre a evolução pós-operatória da HHP, assim como foram questionados objetivamente sobre qualquer ES percebido durante o pós-operatório. Também foram aplicados questionários validados de qualidade de vida para hiperidrose e função erétil. Resultados: Foram entrevistados 10 pacientes do sexo masculino com média de 4,26±2,86 anos pós-SLE. Oito deles (80%) obtiveram resposta completa (≥80% de redução do suor) no primeiro mês após a cirurgia e mantiveram a resposta na entrevista. Dois pacientes tiveram resposta parcial. Em seis pacientes, ocorreu SC, com cinco relatando-a como não problemática. Seis pacientes relataram algum tipo de ES, mas nenhum apresentou disfunção erétil. Todos os pacientes avaliaram o resultado funcional da SLE como bom (10%), muito bom (30%) ou excelente (60%). Conclusões: A SLE pode tratar de forma eficaz a HHP nesses pacientes, melhorando a qualidade de vida e proporcionando efeitos duradouros no controle da HHP, com algumas disfunções sexuais transitórias que não prejudicam a vida sexual.

Impact of Retroperitoneal Lymphadenopathy (RPLN) on the Outcomes of Locally Advanced Gall Bladder Cancer (GBC) Following Chemotherapy (CT) or Chemotherapy Followed by Consolidation Chemoradiotherapy (CTRT).

INTRODUCTION: Retroperitoneal lymphadenopathy is considered a metastatic disease in GBC; however, some surgical series of radical surgery with enlarged RPLN who underwent RPLN dissection have shown results marginally inferior to those without enlarged RPLN. Radiological RPLN comprises a major proportion of advanced non-metastatic GBC. There is dilemma in the intent of treatment to be offered in such cases. We are reporting our series of outcome of GBC with RPLN treated with first-line CT followed by consolidation CTRT. MATERIALS AND METHODS: Non-metastatic locally advanced GBC with good performance status (KPS ≥ 80) were initiated on first-line CT (cisplatin-gemcitabine), and thereafter, responders were evaluated by CECT-angiography and PET-CT scan for resectability. If found unresectable, they were offered consolidation CTRT to a dose of 45 Gy by conventional fractionation (3D-CRT technique) along with concurrent capecitabine at 1250 mg/m2 to GBC and regional lymphatics including RPLN. Thereafter, boost dose of 9 Gy/5# was given to GBC only. Response assessment was done using CECT abdomen by RECIST criteria v 1.1. Outcomes (overall survival) of the two groups (RPLN vs non-RPLN) were computed with Kaplan-Meier survival curves and chi-square tests using SPSS v 20. RESULTS: Among 189 patients of advanced non-metastatic GBC recruited from 2011 to 2022, 80 had RPLN. The demographic features of both groups were comparable. Overall, 68% of the patients were women, 30% underwent upfront stenting for obstructive jaundice, and 90% had T3 and T4 disease. Only 10% had undergone upfront laparoscopic staging and had pathologically proven RPLN. Forty percent of the patients received four cycles of CT only and 50% of the patients received six cycles or more and 33% received CTRT. By RECIST criteria, 10% vs 16% achieved complete response (CR), 39% vs 41% achieved partial response (PR), 16% vs 15% achieved stable disease (SD), 2.7% vs 6% had disease progression (PD), and 14.5% vs 3.7% were non-evaluable in non-RPLN group vs RPLN group, respectively. 12% vs 6% could undergo radical surgery in non-RPLN group vs RPLN group (p = 0.03). The median OS was 9 months (95% CI 7.6-10.3 months) vs 10 months (95% CI 8-9.8 months) (p = NS) in non-RPLN group vs RPLN group, respectively. In those who received CT only, the median OS was 7 months vs 8 months, while in those who received CT followed by CTRT, the median OS was 14 months vs 13 months (p = 0.65) in non-RPLN group vs RPLN group, respectively. CONCLUSIONS: Based on this analysis, we conclude that RPLN constitutes a major proportion of advanced non-metastatic GBC and has outcomes similar to those without RPLN if treated with radical intent. RPLN should not be considered a metastatic disease and should be treated with radical intent.

Anatomical Study of Abdominal Wall Muscle Innervation to Optimize Retroperitoneal Vascular Approach.

INTRODUCTION: Different surgical approaches are used in aortic surgery. Retroperitoneal approaches can result in abdominal wall weakness and flank bulging. These approaches often require dissection of the anterolateral or anteromedial muscles of the abdominal wall. During dissection, the underlying nerves are at great risk of injury, which induces significant complications in abdominal wall muscles. Few studies have been conducted to minimize the risk of injury to these nerves. OBJECTIVES: This study aims to describe the trajectory of abdominal muscle motor nerves and their relationship to ribs and other anatomical landmarks. The secondary objective is to optimize surgical approaches by preserving the nerves. METHOD: We conducted 12 dissections on fresh cadavers. Nerve trajectories, communication between the intercostal nerves (9th-10th-11th) and the subcostal nerve (12th), and the distance from the nerve to the estimated projection point of intersection with the abdominal midline, umbilicus, and iliac crest was recorded. RESULTS: Our dissections identified the 12th subcostal nerve as the largest nerve. The 11th intercostal nerve exhibits more accessory branches than other nerves. Multiple communications and branches were observed between the 10th and 11th intercostal nerves and between the 11th and 12th nerves in the region from the anterior axillary line to the mid-clavicular line. The estimated projection point of intersection with the midline was 7.92 ± 1.24 cm supraumbilical for the 9th intercostal nerve, 3.92 ± 1.18 cm supraumbilical for the 10th, 1.08 ± 1.52 cm at the umbilical level for the 11th, and -3.33 ± 0.83 cm infraumbilical for the subcostal nerve. The distance between the iliac crest and the iliohypogastric nerve in the lateral jackknife position was 2.54 ± 0.65 cm. The 11th nerve had an angle in relation to the rib of between -45° and -10° (average: -24.6°), and the 12th nerve had a similar angle of between -30° and 0° (average: -18.3°). For the 11th nerve, the distance was between 0 and 5.5 cm (average: 2.92 cm); for the 12th nerve, it was between 0 and 3.0 cm (average: 1.71 cm). CONCLUSION: To preserve the 11th nerve, the optimal approach is a straight incision starting from the upper edge of the 11th rib towards the midline, 4 cm above the umbilicus; for the 12th nerve, the optimal approach is a straight incision starting from the upper edge of the 12th rib towards the midline, 1 cm below the umbilicus; for the iliohypogastric nerve, the optimal approach is an incision close to the iliac crest at a distance <1.5 cm. The estimated projection point of intersection between the nerve directions towards the midline can indicate the anatomical trajectory of nerves. A nerve projection towards the midline can provide valuable information about the anatomical location of a nerve. This study has utility in optimizing surgical approaches. A clinical study can confirm these anatomical results.

Exploring the common targets of well-differentiated and dedifferentiated retroperitoneal liposarcoma via gene co-expression analysis.

Objective: This study aimed to identify common therapeutic targets for well-differentiated and dedifferentiated retroperitoneal liposarcoma. Methods: Patient clinical data were obtained from the Surveillance, Epidemiology, and End Results (SEER) database, and survival differences were analyzed using the log-rank test. Gene expression data were sourced from the Gene Expression Omnibus (GEO) dataset GSE159659, with differential gene expression analysis conducted through GEO2R. Protein-protein interaction networks were developed using STRING and Cytoscape to identify key hub genes. Gene Ontology (GO) and KEGG pathway enrichment analyses were performed using R, and transcription factors associated with the hub genes were predicted with TRRUST. Results: Significant survival differences were found between patients with well-differentiated and dedifferentiated retroperitoneal liposarcoma. Ninety-six differentially expressed genes with similar expression patterns were identified in both types. A protein-protein interaction network highlighted 12 hub genes and 24 transcription factors. Enrichment analysis pointed to the importance of lipid localization, storage, cytokine signaling, and metal ion absorption in both liposarcoma subtypes. Four potential therapeutic drugs were successfully predicted. Conclusion: This study identifies common molecular targets in well-differentiated and dedifferentiated retroperitoneal liposarcoma, providing new avenues for mechanistic studies and potential therapeutic development.

Retroperitoneal ancient schwannoma presenting as left flank pain and moderate unilateral hydronephrosis: A case report and literature review.

Key Clinical Message: Benign ancient retroperitoneal schwannomas (BARS) exhibit abdominal masses and flank pain to incidental findings at more advanced stages. Histopathological and immunohistochemical analysis is essential for confirmation of benign nature. Our patient was misdiagnosed as ureteric colic, highlighting the need to consider BARS in differential diagnosis to prevent complications like hydronephrosis. Abstract: Ancient schwannomas are usually benign neoplasms that originate from Schwann cells of peripheral nerves. We present a novel case of a 24-year-old young male with left flank pain and nausea which was initially thought to be left ureteric colic. However, in-depth imaging and biopsy revealed a retroperitoneal mass. The definitive diagnosis was narrowed down to Benign Retroperitoneal Ancient Schwannoma (BARS) via immunohistochemistry and histopathological analysis. This often marble-shaped S100 protein-positive tumor is an under-recognized and potential cause of hydronephrosis if localized near the renal structures. In addition, the retroperitoneal location with infrarenal abdominal aortic adherence is another rare peculiarity in the present case that demands prompt diagnosis and surgical excision to avoid any cardiovascular sequelae such as hypotension and abdominal pain, as indicated by the natural history of growth of this benign tumor. Therefore, timely excision of this benign tumor prior to its further proliferation is paramount. We initially planned laparoscopic removal but adopted excision via laparotomy because of the proximity of the vital structures. The postoperative course of the patient was uneventful and subsequently the patient's presenting complaint of left abdominal flank pain greatly improved. The patient was advised to undergo follow-up computed tomography scan of kidney ureter bladder and RFT evaluation 6 months postsurgery which indicated no evidence of recurrence or iatrogenic complications. The diagnosis and management of the present case share valuable experiences for similar future cases worldwide.

Retroperitoneal Hemorrhage: A Rare Cause of Severe Acute Maternal Morbidity and Perinatal Mortality.

Retroperitoneal hemorrhage in the form of spontaneous adrenal hemorrhage or bleeding into a renal tumor can have varied and non-specific presentations in pregnancy. In the absence of risk factors, these life-threatening conditions are rarely suspected. We present our experience with three patients who presented to us in the third trimester of pregnancy with hemorrhage in retroperitoneal organs. One of the patients had a spontaneous adrenal hemorrhage and the other two had a hemorrhage in the renal tumor. None of the patients was known to have pre-existing tumors, coagulopathy, or trauma. Both the patients with hemorrhage in the renal tumor had intrauterine fetal demise at the time of presentation. Immediate resuscitation and recruitment of a multidisciplinary team resulted in optimal maternal outcomes in all cases and a healthy fetal outcome in the patient with adrenal hemorrhage.

Non-dilated obstructive nephropathy.

Obstructive nephropathy (ON) is a common and reversible cause of post-renal acute kidney injury (AKI) and may be caused by a variety of conditions. It occurs when both the upper urinary tracts are obstructed, or when one tract is obstructed in patients with a solitary kidney. ON is suspected whenever there is evidence of hydronephrosis at imaging. However, not all patients with obstruction develop hydronephrosis and significant obstruction can be present in the absence of hydronephrosis. This syndrome is called non-dilated obstructive uropathy (NDOU). It accounts for about 5% of cases of urinary obstruction and the diagnosis can be challenging. The current paper provides an overview of the literature aiming to identify the main causes of NDOU and its clinical presentation, in order to clarify when to suspect it among AKI cases. A narrative review was performed due to the overall low quality of the available evidence. Only patients with post-renal AKI and a non-dilated or minimal dilation of the intrarenal collecting system were included. As evidenced by our review, NDOU is most prevalent in the fifth and sixth decades of life and affects mainly the male gender. On hospital admission serum creatinine levels are usually very high. Among the most common clinical presentations are oliguria/anuria, abdominal pain, signs of retention such as oedema or pleural effusion, and nausea/vomiting. About three out of four cases of NDOU are due to an ab-extrinsic compression of the ureters caused by retroperitoneal fibrosis or malignant disease. An effective and minimally invasive urinary diversion is obtained with ureteric stenting or a percutaneous nephrostomy. A correct diagnosis of NDOU may be challenging but it is of paramount importance as it can lead to a prompt management with a potential complete resolution of both obstruction and acute renal failure.

Retroperitoneal granuloma in a cat caused by Nocardia brasiliensis resulting in bilateral ureteral entrapment and unilateral hydronephrosis.

Nocardia infections in cats most commonly present as subcutaneous wounds, or less commonly, as pneumonia, purulent pleurisy and disseminated disease. Abdominal involvement is rarely reported, and to date, localised retroperitoneal infection has only been reported in people. This report describes a five-year-old domestic shorthair cat living in Canberra, Australia, that presented with a two-month history of pyrexia and inappetence progressing to anorexia. Ultrasonography showed a large retroperitoneal mass incorporating both ureters. Euthanasia was elected because of the guarded prognosis. Necropsy examination revealed the mass to be comprised of extensive pyogranulomatous inflammation with fibrosis, Splendore-Hoeppli phenomenon and filamentous Gram-positive bacteria. Culture and MALDI-TOF mass spectrometry identified the causative agent as Nocardia brasiliensis. N. brasiliensis is commonly diagnosed as a cause of cutaneous nocardiosis in Australian human patients, but to date has only been reported in one cat from the United States and one dog from Australia. A treatment approach that might have been used in such a case is provided even though the cat's owners elected not to proceed with surgical intervention.

Short and long-term outcomes of arterial and caval replacement during postchemotherapy retroperitoneal lymph node dissection in metastatic testicular cancer.

BACKGROUND AND OBJECTIVE: For patients with metastatic testicular cancer undergoing retroperitoneal lymph node dissection (RPLND), the burden of metastatic disease can require consideration for resection and replacement of major vessels despite chemotherapy. We aimed to clarify the outcomes for patients undergoing these major vascular procedures in a modern era. METHODS: Between 2000 and 2020, 2,054 patients with metastatic testicular cancer underwent a PC-RPLND; of those men, 41 also underwent an aortic, iliac, and/or inferior vena cava (IVC) resection. For men who required a vascular resection, clinicopathologic and operative details were collected. Kaplan-Meier curves were generated to estimate overall survival. RESULTS: The median preoperative mass size was 9cm in the retroperitoneum. Viable malignancy or teratoma was present in 85% of resected specimens. Following PC-RPLND and vascular resection, 22 (54%) patients recurred. The median (IQR) time to relapse was 4.6 (2.5-8.0) months. 18 (44%) patients died of disease. The overall complication rate was 56%. Ten (24%) patients had Clavien-Dindo III/IV complications, with 2 postoperative mortalities. The median overall survival was 14.9 months. Among the 41 patients, 18 patients had re-operative PC-RPLND and vascular resection; the re-operative PC-RPLND patients had significantly worse survival compared to initial attempt at PC-RPLND (9.3 vs. 162 months, P = 0.03). CONCLUSIONS: The overall survival rate for patients undergoing PC-RPLND with resection of the aorta, IVC, and/or iliac artery is 45% at 2 years. For patients with limited treatment options, these complex surgeries may offer survival benefit with an acceptable morbidity profile.

The Role of Cardiovascular Surgeons in Oncovascular Surgery for Resection of Retroperitoneal Tumors: A Case Report.

A 43-year-old man diagnosed with a giant retroperitoneal tumor with suspected invasion of the abdominal aorta and inferior vena cava underwent surgery. Complete en bloc tumor resection could be achieved by transection and reconstruction of the abdominal aorta and inferior vena cava. This case highlights the need for aggressive, complete tumor resection when major vessels are invaded. To ensure comprehensive tumor removal, especially in cases requiring manipulation of major vessels, it is imperative to increase the involvement of cardiovascular surgeons in such surgeries. Therefore, widespread promotion of the concept of oncovascular surgery is essential.

A rare well-differentiated renal retroperitoneal liposarcoma: a case report.

Introduction and importance: Retroperitoneal liposarcomas (RPLPSs) are rare tumors that arise from mesenchymal cells in the peritoneum cavity. The sites of PRLPSs vary a lot, but renal PRLPSs are extremely rare (there are only 45 cases of Renal retroperitoneal liposarcomas on PubMed). In this case, the authors present a rare renal retroperitoneal liposarcoma case, describe the major concepts, and raise awareness about this rare tumor. Case presentation: A 44-year-old woman presented to the clinic with hirsutism and irregular menstruation; upon physical examination, a large abdominal mass was accidentally identified; the patient had Doppler ultrasound (Doppler US) and MRI, which both showed a mass arising from the right upper pole of the kidney, fine needle aspiration (FNA) confirmed the diagnosis of retroperitoneal liposarcoma, patient underwent surgical removal and her symptoms disappeared. Clinical discussion: The retroperitoneum is a cavity behind the abdominal wall containing organs like the pancreas and kidneys. Retroperitoneal tumors (RPTs) are rare neoplasms, primarily of mesenchymal origin. Retroperitoneal liposarcomas (RPLPS) are the most common RPT, often asymptomatic until large, and rarely metastasize but frequently recur. Liposarcomas are classified into five subtypes, with well-differentiated liposarcoma being the most common and characterized by high local recurrence. The presence of specific oncologic mutations affects the prognosis and the response to treatment. Conclusion: In rare cases, retroperitoneal liposarcomas can arise from sites near the kidney and compress the adjoining adrenal gland.

Salmonella bovismorbificans abscess masking a primary testicular tumour in the retroperitoneum - A case report.

INTRODUCTION AND IMPORTANCE: Testicular tumours can present outside the testis in about 5 % of cases, including as a primary lesion within the retroperitoneal space. These arise insidiously and can be hard to detect. Salmonella is an uncommon cause of abscess formation and the subtype of bovismorbificans, arising from geckos, only scarcely reported to cause an abscess. We describe a case in line with SCARE Criteria where a retroperitoneal non-seminomatous germ cell tumour presented with a salmonella bovismorbificans abscess and subsequent bacteraemia. CASE PRESENTATION: A 37 year old male presented unwell with fevers and right flank pain suggestive of pyelonephritis. He had a salmonella bacteraemia on initial blood cultures, subsequently isolated to be salmonella bovismorbificans, and a CT scan demonstrate a large 7.7 cm retroperitoneal mass with surrounding lymphadenopathy. CLINICAL DISCUSSION: An initial attempt at tissue sampling failed as the lesion was filled with purulent material requiring a pig tail drain to remain in place. He progressed slowly with resolution of fevers and bacteraemia however the lesion did not reduce in size despite adequate antibiotic treatment for two weeks. A repeat core biopsy and aspiration after 19 days revealed ongoing salmonella infection with a yolk sac tumour and seminoma. His AFP markers at this time were elevated at 3330kIU/L. CONCLUSION: A underlying malignancy should be consider when a retroperitoneal abscess fails to resolve with adequate treatment especially when a organism unknown to cause abscess is isolated.

Solitary Fibrous Tumor Requiring Abdominal Aortic Vessel Replacement.

Solitary fibrous tumors (SFTs) are mesenchymal tumors, and retroperitoneal occurrence is rare. It has been identified in a variety of soft tissues and organs, such as the pleura, peritoneum, and meninges. In this case, the tumor was in contact with the abdominal aorta, and the invasion was difficult to judge preoperatively. Intraoperatively, it was revealed that the tumor could not be completely removed without aortic replacement. Although SFTs have a generally good prognosis, certain factors, such as tumor incomplete resection, have been reported to increase the risk of recurrence and metastasis. We were able to completely remove the tumor by performing a combined resection of the aorta. The specimens were microscopically disorganized proliferation of spindle-shaped cells. Immunostaining was positive for cluster of differentiation 34 (CD34) and signal transducer and activator of transcription 6 (STAT6). The tumor cells infiltrating into aortic adventitia were observed. This is a valuable case in which artificial blood vessel replacement was able to reduce the risk of recurrence and metastasis due to tumor remnants. We report a rare case of SFT resected with artificial blood vessel replacement.

Efficacy of surgery in the management of multiple recurrences of retroperitoneal dedifferentiated liposarcoma.

BACKGROUND: Retroperitoneal dedifferentiated liposarcoma is associated with a high risk of recurrence; however, treatment strategies that are more effective than surgery remain to be established. This study aimed to determine the optimal number of surgeries that would be effective for patients with recurrent disease. Furthermore, the improvement in prognosis was evaluated according to the malignancy level. METHODS: The effect of each type of surgery on the prognosis of 118 patients with retroperitoneal dedifferentiated liposarcoma treated at the Osaka International Cancer Institute between 1997 and 2022 was investigated. Among the 118 patients, 103 underwent initial surgery, while 54 and 30 patients underwent second and third surgeries, respectively. The overall and disease-free survival rates of each group were compared using the Kaplan-Meier method, and the log-rank test was used to determine statistical significance in univariate analysis. 18F-Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) was used to assess malignancy. Maximum standardized uptake values (SUVmax) of ≥ 4 and < 4 were classified as high and low malignancy, respectively. RESULTS: The first and second surgeries resulted in a significant improvement in the overall survival rate, regardless of the malignancy level (p < 0.001); however, no significant improvement in prognosis was observed after the third surgery (p = 0.077). Low-grade malignancies are associated with a better postoperative prognosis, even in cases of recurrence. In contrast, high-grade malignancies exhibit a reduction in surgical efficacy. CONCLUSIONS: This study highlights the importance of considering the tumor malignancy level and the patient's overall condition when deciding whether to perform repeated surgical interventions. Surgical treatment can prolong overall survival, even in patients with recurrence; however, it is advisable to assess malignancy levels when determining the suitability of surgery beyond the second recurrence.

Surgical Strategies and Perioperative Outcomes of Robot-Assisted Vena Cava Reconstruction.

BACKGROUND: This study aimed to describe robot-assisted vena cava reconstruction by summarising surgical strategies and perioperative outcomes. METHODS: A retrospective review was performed on all robotic surgeries involving dissection and repair of the inferior vena cava (IVC) at our institution. Patient characteristics, operative reports, and follow-up visits were analysed. RESULTS: Thirty-nine patients underwent robot assisted surgery of the vena cava from 2016 to 2023. The median postoperative hospital stay of all patients was 7 days, and the median estimated blood loss (EBL) was 550 mL. The median IVC clamping time was 23 min, and IVC wall invasion was pathologically identified in five cases. No patients had liver or kidney dysfunction at the last follow-up. CONCLUSION: Our initial experiences demonstrate that it is safe and feasible for experienced surgeons to perform robot-assisted vena cava reconstruction in highly selected patients.

Retroperitoneal soft tissue sarcomas: Predictive factors for incomplete resection.

INTRODUCTION: Curative management of retroperitoneal sarcoma relies on surgery, and complete monoblock resection is one of the main prognostic factors. The goal of this study was to search predictive factors for incomplete resection. METHODS: All patients undergoing surgery for retroperitoneal sarcoma in two University hospitals between 2010 and 202 were included. The main endpoint was incomplete resection (R1 ad R2) after surgery. Secondary analysis was performed where marginal R0 resection was considered as complete. Univariate and multivariable analysis of demographics, radiological, surgical and pathologic criteria were performed. Overall survival, local and distant recurrence were evaluated. RESULTS: Fifty-eight patients were included in the study. Fifty patients had incomplete resection, of which seven had marginal R0 resection. In multivariable analysis, none of the factors analyzed were associated with incomplete resection. In secondary analysis, undifferentiated liposarcoma histology (OR 12.3, 95% CI [1.416-107.303], P=0.023) was statistically significantly associated with incomplete resection. Low grade (grade I) histology was predictive of complete resection (OR 0.24, 95% CI [0.060-0.959], P=0.043). Median follow-up duration was 27 months. Local and distant recurrence rates at three years were 37% and 22.4%, respectively. CONCLUSION: In this study, we highlighted several predictive factors for incomplete resection. These factors enable us to define target populations that could most benefit from complementary therapy along with surgery.