Current diagnosis and management of retroperitoneal sarcoma

Retroperitoneal leiomyosarcoma diagnosis and management in a chronic kidney disease context: A case report

INTRODUCTION AND IMPORTANCE

While the treatment approach for sarcomas seems straightforward and well-defined, we often encounter several diagnostic or therapeutic challenges in clinical practice. This article presents a case of retroperitoneal leiomyosarcoma in a patient with chronic kidney disease, highlighting the complexity of managing such cases.

CASE REPORT

A 63-year-old woman with a history of chronic kidney disease presented with a progressively enlarging mass in her right flank. A CT scan revealed a retroperitoneal mass affecting the muscular layer of the right lumbar ureter, without invading the kidney. Percutaneous biopsies concluded to a smooth muscle tumor with positive anti-caldesmone and anti-desmin antibodies. A 99 m Tc DMSA renal revealed significant impairment of the right kidney function while the left kidney function remained normal. The surgical procedure involved removing the mass, as well as the right kidney and ureter. Histopathological examination confirmed the diagnosis of leiomyosarcoma. No locoregional recurrence or metastases were noted after a 13-month follow-up.

DISCUSSION

Leiomyosarcomas are malignant tumors that can affect various organs, with retroperitoneum being the second most common location. A CT scan and abdominal MRI are standard imaging technique to evaluate this disease. Percutaneous biopsy and pathology are performed to confirm the nature of the tumor, especially when neoadjuvant treatment is necessary for metastatic tumors. Compartmental resection with clear margins is the only potential curative treatment. Even after R0 resection the risk of recurrence varies between 20 and 75 %.

CONCLUSION

Managing retroperitoneal leiomyosarcoma, especially in patients with comorbidities like chronic kidney disease, necessitates a multidisciplinary approach.

Updated Review and Clinical Recommendations for the Diagnosis and Treatment of Patients with Retroperitoneal Sarcoma by the Spanish Sarcoma Research Group (GEIS)

Soft tissue sarcomas (STS) are an uncommon and biologically heterogeneous group of tumors arising from mesenchymal cells. The incidence is estimated at five cases per 100,000 people per year. Retroperitoneal sarcomas (RPS) account for 10-15% of all STS, and their management depends on their anatomical characteristics and histotype. Due to their very low incidence, it is recommended that RPS be treated in reference centers and evaluated by an experienced multidisciplinary team (MDT). In Spain, the Spanish Group for Research in Sarcomas (GEIS) brings together experts from various specialties to promote research on sarcomas and improve treatment results. This paper summarizes the GEIS recommendations for the diagnosis, treatment, and follow-up of patients with RPS.

Soft Tissue Sarcoma, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology

Soft tissue sarcomas (STS) are rare malignancies of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Soft Tissue Sarcoma provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as retroperitoneal/intra-abdominal STS, desmoid tumors, and rhabdomyosarcoma. This portion of the NCCN Guidelines discusses general principles for the diagnosis and treatment of retroperitoneal/intra-abdominal STS, outlines treatment recommendations, and reviews the evidence to support the guidelines recommendations.

Pleomorphic Rhabdomyosarcoma: A Systematic Review with Outcome Analysis and Report of a Rare Abdominal Wall Lesion

Introduction. Pleomorphic rhabdomyosarcoma (RMS) is an aggressive and rare malignant neoplasm with a poor prognosis. As its name suggests, this tumor exhibits extensive pleomorphism with features of skeletal muscle differentiation. Due to its rarity, its diagnosis is often a clinical and pathological challenge. Since only small case series and a few scattered case reports exist in the literature, the impact of different demographic features, tumor site, and/or treatment modality on patient outcomes has yet to be extensively studied. Methods. We report a case of a pleomorphic RMS presenting atypically as an abdominal wall mass. We have also analyzed the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) database to determine the factors affecting the outcome of this neoplasm. Moreover, we present a review and summary of pleomorphic RMS cases arising from the abdominal wall reported in the English language literature. Results. We found two hundred and forty-two cases of pleomorphic RMS in the SEER database. The majority of the patients were diagnosed after the age of 40, with the age of diagnosis showing a unimodal distribution. The majority of the patients were Caucasian (82%) and male (59%). Age of diagnosis, tumor stage, and surgical management significantly affected the patients' outcome, while patients' ethnicity, sex, or tumor site did not affect the outcome. We only found five previously reported cases of pleomorphic RMS arising from the abdominal wall. Conclusions. Pleomorphic RMS arising from the abdominal wall is extremely rare. Our data sheds light on the factors affecting the outcome of pleomorphic RMS. We have also discussed the challenges involving the histopathological diagnosis of this rare neoplasm and how to best approach this task.

The Role of Surgical Expertise and Surgical Access in Retroperitoneal Sarcoma Resection – A Retrospective Study

Background

Retroperitoneal sarcoma (RPS) is a rare disease often requiring multi-visceral and wide margin resections for which a resection in a sarcoma center is advised. Midline incision seems to be the access of choice. However, up to now there is no evidence for the best surgical access. This study aimed to analyze the oncological outcome according to the surgical expertise and also the incision used for the resection.

Methods

All patients treated for RPS between 2007 and 2018 at the Department of Visceral Surgery and Medicine of the University Hospital Bern and receiving a RPS resection in curative intent were included. Patient- and treatment specific factors as well as local recurrence-free, disease-free and overall survival were analyzed in correlation to the hospital type where the resection occurred.

Results

Thirty-five patients were treated for RPS at our center. The majority received their primary RPS resection at a sarcoma center (SC = 23) the rest of the resection were performed in a non-sarcoma center (non-SC = 12). Median tumor size was 24 cm. Resections were performed via a midline laparotomy (ML = 31) or flank incision (FI = 4). All patients with a primary FI (n = 4) were operated in a non-SC (p = 0.003). No patient operated at a non-SC received a multivisceral resection (p = 0.004). Incomplete resection (R2) was observed more often when resection was done in a non-SC (p = 0.013). Resection at a non-SC was significantly associated with worse recurrence-free survival and disease-free survival after R0/1 resection (2 vs 17 months; Log Rank p-value = 0.02 respectively 2 vs 15 months; Log Rank p-value < 0.001).

Conclusions

Resection at a non-SC is associated with more incomplete resection and worse outcome in RPS surgery. Inadequate access, such as FI, may prevent complete resection and multivisceral resection if indicated and demonstrates the importance of surgical expertise in the outcome of RPS resection.

Targetable Pathways in the Treatment of Retroperitoneal Liposarcoma

Liposarcoma (LPS) is the most prevalent soft tissue sarcoma histological subtype. When it occurs in the abdomen the overall survival rate is as low as 10% at 10 years and is fraught with high rates of recurrence, particularly for the more aggressive dedifferentiated subtype. Surgery remains the mainstay of treatment. Systemic therapies for the treatment of metastatic or unresectable disease have low response rates. Deep understanding of well-differentiated and de-differentiated LPS (WDLPS and DDLPS, respectively) oncologic drivers is necessary for the development of new efficacious targeted therapies for the management of this disease. This review discusses the current treatments under evaluation for retroperitoneal DDLPS and the potential targetable pathways in DDLPS.

Robotic Nerve Sheath Tumor Resection With Intraoperative Neuromonitoring: Case Series and Systematic Review

BACKGROUND

Retroperitoneal nerve sheath tumors present a surgical challenge. Despite potential advantages, robotic surgery for these tumors has been limited. Identifying and sparing functional nerve fascicles during resection can be difficult, increasing the risk of neurological morbidity.

OBJECTIVE

To review the literature regarding robotic resection of retroperitoneal nerve sheath tumors and retrospectively analyze our experience with robotic resection of these tumors using a manual electromyographic probe to identify and preserve functional nerve fascicles.

METHODS

We retrospectively analyzed the clinical courses of 3 patients with retroperitoneal tumors treated at the National Institutes of Health by a multidisciplinary team using the da Vinci Xi system. Parent motor nerve fascicles were identified intraoperatively with a bipolar neurostimulation probe inserted through a manual port, permitting tumor resection with motor fascicle preservation.

RESULTS

Two patients with neurofibromatosis type 1 underwent surgery for retroperitoneal neurofibromas located within the iliopsoas muscle, and 1 patient underwent surgery for a pelvic sporadic schwannoma. All tumors were successfully resected, with no complications or postoperative neurological deficits. Preoperative symptoms were improved or resolved in all patients.

CONCLUSION

Resection of retroperitoneal nerve sheath tumors confers an excellent prognosis, although their deep location and proximity to vital structures present unique challenges. Robotic surgery with intraoperative neurostimulation mapping is safe and effective for marginal resection of histologically benign or atypical retroperitoneal nerve sheath tumors, providing excellent visibility, increased dexterity and precision, and reduced risk of neurological morbidity.

18F-Fluorodeoxyglucose Positron Emission Tomography Is Useful in the Evaluation of Prognosis in Retroperitoneal Sarcoma

Simple Summary

Retroperitoneal sarcomas are difficult malignancies to treat because complete surgical resection is the only effective treatment option, but it is difficult to secure sufficient surgical margins. It is essential for developing a treatment strategy to assess tumor aggressiveness and predict prognosis for patients. However, the aggressiveness of retroperitoneal sarcomas before treatment cannot be fully evaluated. In patients with resectable soft tissue sarcomas or several carcinomas, SUV evaluated with FDG-PET has been reported to be a valuable prognostic parameter. However, the correlation between SUVmax on FDG-PET and the prognosis of several histological subtypes in retroperitoneal sarcoma, including dedifferentiated liposarcoma, well-differentiated liposarcoma, and leiomyosarcoma, remains uncertain. This study revealed that SUVmax calculated with FDG-PET was useful as a prognostic factor in retroperitoneal sarcoma, especially in dedifferentiated liposarcoma and Grade2 retroperitoneal sarcoma.

Abstract

Background: Retroperitoneal sarcomas are rare neoplasms that occur in the retroperitoneum. Complete surgical resection is the only effective treatment option. The prediction of prognosis by histological diagnosis has not yet been established. The purpose of this study was to identify the usefulness of [18-F] fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging for validating the prognosis of retroperitoneal sarcoma (RPS) established by histological diagnosis. Methods: We retrospectively reviewed 201 patients with RPS treated at the Osaka International Cancer Institute between 2010 and 2021. We extracted the clinical data, including standardized uptake values (SUVs), evaluated with FDG-PET, and statistically analyzed the data. Results: The median age of patients was 64 years (range, 31–85 years). A total of 101 (50.2%) patients were men, and 100 (49.8%) were women. Surgical resection was performed in 155 (77.1%) patients. On histological analysis, 75 (37.3%), 52 (25.9%), and 29 (14.4%) patients were diagnosed with dedifferentiated liposarcoma, well-differentiated liposarcoma, and leiomyosarcoma, respectively. The median survival time for patients with high maximum SUV (SUVmax) (≥4) or low SUVmax (<4) was 275.8 months and 79.5 months, respectively. Furthermore, among the patients with dedifferentiated liposarcoma, the overall survival rate for patients with high SUVmax (≥4) was significantly lower than that of those with low SUVmax (<4). Conclusions: The present study demonstrated that SUVmax calculated with FDG-PET was useful as a prognostic factor in RPS, especially in dedifferentiated liposarcoma and Grade2 RPS. To devise a treatment strategy for RPS, SUVmax during FDG-PET scan may be considered for clinical assessment.

Potential application value of PET/computed tomography in retroperitoneal leiomyosarcoma and a literature review

OBJECTIVE

To analyze the fluorine-18 fludeoxyglucose PET/computed tomography (18F-FDG PET/CT) findings of retroperitoneal leiomyosarcoma (RLMS) and the role of this method in differentiating between benign and malignant masses and classifying the malignant degree to improve the understanding of this rare disease.

METHODS

Eight leiomyomas (A group), 13 RLMSs (B group), and 20 postoperative recurrence/metastasis RLMSs (C group) were enrolled. PET/CT features of B group were analyzed. The differences of metabolic parameters between three groups were compared, receiver operating characteristic (ROC) curve analysis was performed to group A and B, and correlation analysis was performed to subgroup B.

RESULTS

(1) The RLMS patients were more likely to be female, and PET/CT showed a high degree of heterogeneous metabolism in the soft tissue mass. (2) The standardized uptake value (SUV) of RLMS were significantly higher than those of benign leiomyomas (P < 0.05). The area under the ROC curve was 0.909, the sensitivity and specificity for diagnosing RLMS were 0.923 and 0.750, respectively, The SUVmax and SUVstd of primary RLMS were moderately associated with the Ki67 index. The mean SUVmax in the G1, G2 and G3 subgroups increased successively (4.15 ± 0.35, 6.47 ± 0.83, and 10.13 ± 4.29, respectively). (3) Primary RLMS was characterized by local invasion, but hematogenous metastasis and lymph node metastasis were rare. Postoperative recurrence/metastasis of RLMS was characterized by local recurrence and hematogenous metastasis, but lymph node metastasis was rare.

CONCLUSION

PET/CT has potential value in the preoperative staging, benign and malignant differentiation, malignant degree classification and postoperative follow-up of RLMS.

Surgical Diagnosis and Treatment of Primary Retroperitoneal Liposarcoma

Background: Primary retroperitoneal liposarcoma (PRPLS) is the most common soft tissue sarcoma of the retroperitoneum with high recurrence rate and short overall survival (OS).

Methods: A retrospective review of 51 patients with PRPLS, treated between September 1, 2009 and November 30, 2020, was conducted to evaluate clinical outcomes of PRPLS resection. Patient demographics, histopathologic subtypes, overall survival (OS), progression-free survival (PFS), disease recurrence rate, and tumor stage were reviewed and analyzed. Univariate analysis was done to identify factors potentially affecting OS and PFS of PRPLS patients. Multivariate Cox proportional hazards analysis was used to evaluate the impact of various clinicopathological factors on OS and PFS of PRPLS patients.

Results: Fifty-one PRPLS patients (28 Males, 23 Females; mean age 56.25 years) were evaluated. There was no significant effect of age, gender, contiguous organ resection, degree of differentiation and tumor size on the OS and PFS of the patients. Univariate analysis showed that negative surgical margin and early tumor stage significantly correlated with OS and PFS (all P < 0.001). Multivariate analysis showed that tumor stage [hazard ratio (HR) = 1.177, P = 0.001] was an independent predictors of poor progression-free survival, and surgical margins [HR = 4.0674 P = 0.038] and tumor stage [HR = 1.167 P = 0.001] were identified as independent predictors of poor overall survival.

Conclusion: Negative surgical margin is a prognostic factor of OS, and can prolong the postoperative survival time of PRPLS patients. Tumor stage is a prognostic factor for OS and PFS, and can influence the survival of PRPLS patients. Earlier tumor stages of PRPLS are associated with significantly better outcomes.

Preoperative Biopsy in Patients with Retroperitoneal Sarcoma: Usage and Outcomes in a National Cohort

INTRODUCTION

Preoperative biopsy (PBx) is often recommended for retroperitoneal sarcoma (RPS), but its utilization rate and impact on perioperative management and outcomes remains undefined.

METHODS

Using the National Cancer Database, patients who underwent resection of non-metastatic RPS were identified (2006-2014). Patients who did and did not undergo PBx of the primary tumor were compared using propensity matching, and factors associated with survival were assessed by multivariable analysis.

RESULTS

Of 2620 patients, 1110 (42.4%) underwent PBx. Factors significantly associated with performance of PBx included male sex [odds ratio (OR) 1.2, P = 0.035], tumor size ≤ 5 cm (OR 1.5, P = 0.012), tumor size > 5 to ≤ 10 cm (OR 1.3, P = 0.009), non-well-differentiated liposarcoma histology (OR 2.0, P ≤ 0.001), and treatment at a high-volume center (OR 1.3, P = 0.021). Receipt of PBx was significantly associated with administration of neoadjuvant radiation (OR 8.8, P < 0.001) or systemic therapy (OR 3.3, P < 0.001), radical surgical resection (OR 1.6, P < 0.001), and complete tumor resection (OR 1.5, P < 0.003). Neoadjuvant radiation [hazard ratio (HR) 0.7, P = 0.003] and complete tumor resection (HR 0.6, P < 0.001) were significantly associated with improved overall survival (OS). Performance of PBx was not associated with OS (HR 1.1, P = 0.070), and following propensity matching, 5-year OS did not differ between the two groups (56.5% PBx vs 58.4% no PBx, P = 0.247).

CONCLUSIONS

A minority of patients with non-metastatic RPS undergo PBx. PBx does not negatively impact survival, but may indirectly improve outcomes in select patients by virtue of receipt of neoadjuvant therapy and attainment of complete tumor resection.

Soft-tissue sarcoma in adults: An update on the current state of histiotype-specific management in an era of personalized medicine

Soft-tissue sarcomas (STS) are rare tumors that account for 1% of all adult malignancies, with over 100 different histologic subtypes occurring predominately in the trunk, extremity, and retroperitoneum. This low incidence is further complicated by their variable presentation, behavior, and long-term outcomes, which emphasize the importance of centralized care in specialized centers with a multidisciplinary team approach. In the last decade, there has been an effort to improve the quality of care for patients with STS based on anatomic site and histology, and multiple ongoing clinical trials are focusing on tailoring therapy to histologic subtype. This report summarizes the latest evidence guiding the histiotype-specific management of extremity/truncal and retroperitoneal STS with regard to surgery, radiation, and chemotherapy.

Analysis of outcomes and predictors of long-term survival following resection for retroperitoneal sarcoma

BACKGROUND

Retroperitoneal sarcomas (RPS) include a heterogeneous group of rare malignant tumours, and various treatment algorithms are still controversially discussed until today. The present study aimed to examine postoperative and long-term outcomes after resection of primary RPS.

PATIENTS AND METHODS

Clinicopathological data of patients who underwent resection of primary RPS between 2005 and 2015 were assessed, and predictors for overall survival (OS) and disease-free survival (DFS) were identified.

RESULTS

Sixty-one patients underwent resection for primary RPS. Postoperative morbidity and mortality rates were 31 and 3%, respectively. After a median follow-up time of 74 months, 5-year OS and DFS rates were 58 and 34%, respectively. Histologic high grade (5-year OS: G1: 92% vs. G2: 54% vs. G3: 43%, P = 0.030) was significantly associated with diminished OS in univariate and multivariate analyses. When assessing DFS, histologic high grade (5-year DFS: G1: 63% vs. G2: 24% vs. G3: 22%, P = 0.013), positive surgical resection margins (5-year DFS: R0: 53% vs. R1: 10% vs. R2: 0%, P = 0.014), and vascular involvement (5-year DFS: yes: 33% vs no: 39%, P = 0.001), were significantly associated with inferior DFS in univariate and multivariate analyses.

CONCLUSIONS

High-grade tumours indicated poor OS, while vascular involvement, positive surgical resection margins, and histologic grade are the most important predictors of DFS. Although multimodal treatment strategies are progressively established, surgical resection remains the mainstay in the majority of patients with RPS, even in cases with vascular involvement.

Huge primary dedifferentiated pancreatic liposarcoma mimicking carcinosarcoma in a young female: A case report

BACKGROUND

Pancreatic liposarcoma is a rare tumor. According to a literature review, the patient described in this study is the seventh case of pancreatic liposarcoma reported in the English literature and the third case of dedifferentiated liposarcoma. Furthermore, this case had the largest primary tumor volume, and a primary pancreatic liposarcoma was diagnosed based on sufficient evidence.

CASE SUMMARY

We here report a rare case of a 28-year-old female with a huge dedifferentiated liposarcoma in the pancreatic tail. In June 2015, the patient underwent distal pancreatectomy with splenectomy. During the operation, a huge liposarcoma of approximately 28.0 cm × 19.0 cm × 8.0 cm was found, which had a yellow and white fish-like incisal surface. Based on both pathology and MDM2 gene amplification, the tumor was diagnosed as a dedifferentiated liposarcoma. The patient was treated with surgery but declined postoperative chemotherapy. She was well at the 26-mo follow-up, and no relapse was observed.

CONCLUSION

Pancreatic liposarcoma has a low incidence. Chemotherapy should be included in the treatment regimens. Complete resection is the only effective treatment.

Management of primary retroperitoneal synovial sarcoma: A case report and review of literature

BACKGROUND

Synovial sarcoma (SS) is a rare type of soft tissue sarcoma that is usually developed from areas where synovial tissue exists, especially at the extremities. Nevertheless, several cases of retroperitoneal SS (RSS) have been described. We herein report a case of RSS presented in our institution.

CASE SUMMARY

A 69-year-old female patient was admitted with a large, palpable, firm mass in the right abdominal space SS. Computerized tomography scan depicted a concentric, sharply marinated retro-peritoneal lesion which was displacing the right kidney and the lower edge of the liver. Subsequently, the patient underwent surgical excision of the mass with additional right nephrectomy and resection of the right adrenal gland and a part of the diaphragm. The final histological diagnosis of the tumour was grade II monophasic RSS.

CONCLUSION

RSS is encountered in the biphasic type, the monophasic fibrous, and the monophasic epithelial category as well. Relevant clinical manifestations are not always documented at early stages. Therefore, the final diagnosis is posed after complete histological examination taking into consideration the results of immunochemistry and genetic analysis. Therapeutic approach happens often late when metastases at the lungs and the liver are apparent. Thus, 5-year survival rates remain low.

Incisions and reconstruction approaches for large sarcomas

Large intraabdominal, retroperitoneal, and abdominal wall sarcomas provide unique challenges in treatment due to their variable histology, potential considerable size at the time of diagnosis, and the ability to invade into critical structures. Historically, some of these tumors were considered inoperable if surgical access was limited or the consequential defect was unable to be closed primarily as reconstructive options were limited. Over time, there has been a greater understanding of the abdominal wall anatomy and mechanics, which has resulted in the development of new techniques to allow for sound oncologic resections and viable, durable options for abdominal wall reconstruction. Currently, intra-operative positioning and employment of a variety of abdominal and posterior trunk incisions have made more intraabdominal and retroperitoneal tumors accessible. Primary involvement or direct invasion of tumor into the abdominal wall is no longer prohibitive as utilization of advanced hernia repair techniques along with the application of vascularized tissue transfer have been shown to have the ability to repair large area defects involving multiple quadrants of the abdominal wall. Both local and distant free tissue transfer may be incorporated, depending on the size and location of the area needing reconstruction and what residual structures are remaining surrounding the resection bed. There is an emphasis on selecting the techniques that will be associated with the least amount of morbidity yet will restore and provide the appropriate structure and function necessary for the trunk. This review article summarizes both initial surgical incisional planning for the oncologic resection and a variety of repair options for the abdominal wall spanning the reconstructive ladder.

Retroperitoneal Leiomyosarcoma From the Radiologic Pathology Archives

Leiomyosarcoma is a malignant neoplasm that shows smooth muscle differentiation. It is the second most common sarcoma to affect the retroperitoneum. Retroperitoneal leiomyosarcomas may grow to large sizes before detection and may be an incidental finding at imaging. When symptomatic, retroperitoneal leiomyosarcoma may cause compressive symptoms, including pain. Retroperitoneal leiomyosarcoma most commonly manifests as a large soft-tissue mass, with areas of necrosis. The most frequent pattern of growth is an entirely extravascular mass. Less commonly, leiomyosarcoma may demonstrate both extravascular and intravascular components. Rarely, retroperitoneal leiomyosarcomas are completely intravascular, typically arising from the inferior vena cava. Given its variable imaging features, a large variety of neoplastic and nonneoplastic conditions are included in the differential diagnosis of retroperitoneal leiomyosarcoma. In this review, the authors discuss retroperitoneal leiomyosarcoma, with emphasis on the pathologic basis of disease, and illustrate the multimodality imaging appearances of retroperitoneal leiomyosarcoma using cases from the Radiologic Pathology Archives of the American Institute for Radiologic Pathology. The authors review important differential considerations of retroperitoneal leiomyosarcoma, focusing on the extravascular pattern of growth, and emphasize clinical and imaging features that help radiologists differentiate leiomyosarcoma from the most frequent mimics. The information presented in this review will aid radiologists in fulfilling their key roles in the diagnosis, operative planning, and follow-up of patients with retroperitoneal leiomyosarcoma.

Neoadjuvant and adjuvant strategies in retroperitoneal sarcoma

Extended surgery remains the mainstay of treatment in retroperitoneal sarcoma, although conflicting data exist on the benefit of neoadjuvant and adjuvant therapies, particularly with regard to tumour grade and histological type. Experience of radiotherapy and chemotherapy in extremity soft tissue sarcoma can inform treatment strategies, however these data cannot be universally extrapolated to the retroperitoneum where disease biology and anatomical considerations are different. The present review sets a historical context before discussing recent evidence and on-going multi-centre trials in retroperitoneal sarcoma. Promising data on histologically- and molecularly-targeted chemotherapy are discussed and the need for centralisation of retroperitoneal sarcoma services in order to facilitate large international collaborative trials is emphasised.

Acute haemorrhage from a retroperitoneal liposarcoma: a rare presentation

A previously healthy 61-year-old Caucasian woman presented to the emergency department after collapsing at home with associated abdominal pain radiating to her back. An urgent CT angiogram was requested to rule out a ruptured aortic aneurysm. This showed a large 21 cm fat-containing lesion arising from the mid-pole of the left kidney, with an adjacent 4 cm perirenal haematoma. An initial diagnosis of a ruptured angiomyolipoma was made. Her haemoglobin was 105 g/L, with a creatinine of 104 mmol/L and an eGFR of 47 mL/min. Her clotting profile was normal. Following resuscitation, she was taken to the operating room and underwent an emergency open left radical nephrectomy via a left flank incision. Her recovery was uneventful and she was discharged home after 6 days. The histopathology confirmed a well-differentiated liposarcoma.

Local Control of Soft Tissue and Bone Sarcomas

Sarcomas of soft tissue and bone are mesenchymal malignancies that can arise in any anatomic location, most commonly the extremity, retroperitoneum, and trunk. Even for lower grade histologic subtypes, local recurrence can cause significant morbidity and even disease-related death. Although surgery remains the cornerstone of local control, perioperative radiation and systemic therapy are often important adjuvants. This review will summarize the current therapeutic approaches for local control of soft tissue and bone sarcomas.

Imaging in retroperitoneal soft tissue sarcoma

Patients with retroperitoneal sarcoma can present to a variety of clinicians with non‐specific symptoms and retroperitoneal sarcomas can be incidental findings. Failure to recognize retroperitoneal sarcomas on imaging can lead to inappropriate management in non‐specialist centers. Therefore it is critical that the possibility of retroperitoneal sarcoma should be considered with prompt referral to a soft tissue sarcoma unit. This review guides clinicians through a diagnostic pathway, introduces concepts in response assessment and new imaging developments.

Imaging Diagnosis of a Rare Presacral Tumour

Background

Primary tumors in the presacral (retrorectal) space are extremely rare in adults, with an estimated incidence of 0.0025 to 0.014 in large referral centers. Congenital varieties are most common and comprise two thirds of these tumors. Primary retroperitoneal sarcomas in the pelvic region are extremely rare. We report the ultrasound and the corresponding Computed Tomography (CT) features of a rare presacral fibrosarcoma in an adult woman, in whom the diagnosis was confirmed by a CT-guided biopsy.

Case Report

A 54-year-old woman presented with a history of lumbar and perineal pain and painful defecation. Rectal examination revealed a hard mass in the retrorectal space. The patient was referred for imaging and a laboratory evaluation with a clinical diagnosis of a presacral mass. An abdominal ultrasound was followed by laboratory evaluation of routine hematological and hepato-renal parameters, abdomino-pelvic CT and a CT-guided biopsy.

The imaging studies showed a presacral solid mass with nodular calcifications. There was conspicuous absence of cystic or adipose contents and of sacral erosion/destruction. However, hepatic metastasis was present. All imaging features suggested a retroperitoneal sarcoma in the pelvic region with metastases to the liver. The diagnosis was confirmed by CT-guided biopsy.

Conclusions

We are reporting a new case of a very rare entity, a presacral fibrosarcoma. The imaging approach and the analysis leading to an appropriate differential diagnosis and final diagnosis is highlighted in our case report.

Contemporary reappraisal of the efficacy of adjuvant chemotherapy in resected retroperitoneal sarcoma: Evidence from a nationwide clinical oncology database and review of the literature

BACKGROUND

While margin-negative resection remains the cornerstone of therapy for retroperitoneal sarcoma (RPS), the impact of adjuvant chemotherapy (AC) on overall survival (OS) remains poorly understood.

METHODS

The National Cancer Data Base was queried for patients undergoing curative-intent resection of primary non-metastatic RPS (2004-2013). Multivariable modeling identified factors associated with AC receipt. Cox regression identified covariates associated with OS, and AC and surgery alone (SA) cohorts were matched 1:1 by propensity scores based on these covariates. In the propensity-score matched cohort, OS was compared by Kaplan-Meier estimates. Results from this analysis were presented in the context of a review of the existing literature on the impact of AC in resected RPS.

RESULTS

Of 3892 resected RPS patients, 90.0% and 10.0% received SA and AC, respectively. Predictors of AC receipt included younger age, non-Caucasian race, hospital location, histologic grade, adjacent organ invasion, and histologic subtype. The propensity score-matched cohort comprised 767 patients (SA n = 377; AC n = 390); at a median follow-up of 59.2 (IQR 35.0-85.3) months, median OS of the propensity-matched cohort was 53.6 (IQR 22.4-119.5) months. Utilization of AC was associated with significantly worse long-term survival (median OS: 47.8 vs. 68.9 months, p = 0.017; HR 1.30, 95% CI 1.05-1.61). AC was not associated with improved OS in margin-positive (R1/R2) resection, high-grade (G2/G3) and larger (>10 cm) tumors, or in any histologic subtype. Albeit not statistically significant, there was a trend toward improved OS with AC in spindle cell (HR 0.37, 95% CI 0.10-1.38), giant cell (HR 0.82, 95% CI 0.32-2.13), and synovial (HR 0.26, 95% CI 0.05-1.33) sarcoma.

CONCLUSIONS

Data from a large nationwide oncology database and review of the existing literature do not support adjuvant chemotherapy regimens following curative-intent resection of RPS, even in subgroups at high risk of failure (e.g., R1/R2 resection, high-grade or large tumors). The possible benefit of conventional adjuvant regimens in spindle cell, giant cell, and synovial sarcoma should be explored in prospective studies.

Effect of intraoperative radiotherapy in the treatment of retroperitoneal sarcoma

BACKGROUND

Current National Comprehensive Cancer Network guidelines for the treatment of retroperitoneal sarcomas (RPS) endorse surgical resection, but the role of radiotherapy (RT) is less clear. We investigate the utilization and benefits of intraoperative RT (IORT) in the treatment of RPS.

METHODS

We queried the Surveillance, Epidemiology and End Results (SEER) database (1988-2013) for the utilization of IORT and perioperative external beam RT (EBRT) in patients who underwent surgical resection of RPS. Groups were defined as any IORT (aIORT), IORT alone (IORT-), IORT with EBRT (IORT+) and preoperative and/or postoperative EBRT without IORT (EBRT). Demographics, tumor characteristics, extent of disease, and survival were compared between groups.

RESULTS

We identified 908 patients with RPS who underwent surgical resection with perioperative RT. Demographics of age, sex, and race were similar between groups. There was no difference in baseline tumor characteristics of mean size, tumor grade, or histological subtype between groups. A higher percentage of patients receiving aIORT had tumors >20 cm in size, and extension beyond local tissues. Liposarcoma and leiomyosarcoma were the most common subtypes overall and in each subgroup. Patients with liposarcoma undergoing IORT and EBRT (IORT+) demonstrated a survival benefit over both IORT alone (IORT-) and EBRT alone.

CONCLUSION

IORT was used infrequently for RPS but generated equivalent outcomes compared to EBRT, despite being utilized more often for larger tumors and those with peri-tumoral soft-tissue invasion. Patients with the most common subtype (liposarcoma) may benefit from combination IORT with adjuvant EBRT versus other regimens.

Primary retroperitoneal soft tissue sarcoma: Imaging appearances, pitfalls and diagnostic algorithm

Although retroperitoneal sarcomas are rare tumours, they can be encountered by a wide variety of clinicians as they can be incidental findings on imaging or present with non specific symptoms and signs. Surgical resection can offer hope of cure and patient outcomes are improved when patients are managed in high-volume specialist centers. Failure to recognize retroperitoneal sarcomas on imaging can lead to inappropriate management in inexperienced centers. Therefore it is critical that a diagnosis of retroperitoneal sarcoma should be considered in the differential diagnosis of a retroperitoneal mass with prompt referral to a soft tissue sarcoma unit. In particular, the most common retroperitoneal sarcoma subtypes, liposarcoma and leiomyosarcoma, have characteristic imaging appearances which are discussed. This review therefore aims to set the context and guide clinicians through a diagnostic pathway for retroperitoneal masses in adults which arise extrinsic to the solid abdominal viscera.

CT-guided 125I seed implantation for inoperable retroperitoneal sarcoma: A technique for delivery of local tumor brachytherapy

Radical surgery is currently the first treatment of choice for retroperitoneal soft tissue sarcoma (RSTS). However, the prognosis of RSTS remains poor due to ineffective local control and a high incidence of metastasis after surgical resection. Brachytherapy has been shown to safely provide local radiotherapy for numerous types of cancer when used alone or in combination with surgical resection, but has not been well characterized in the management of RSTS. The aim of this study was to evaluate CT-guided 125I seed implantation for local control and pain relief in the treatment of inoperable RSTS. A total of 23 patients with RSTS were treated with 125I implantation. Pain was assessed using a visual analog scale. Other endpoints were evaluated via computed tomography scan or phone call/e-mail records. The occurrence of complications was assessed preoperatively (baseline) and during postoperatively follow-up or until patient succumbed. All patients were successfully treated with 125I implantation. A mean number of 70.87 radioactive seeds were applied in each patient. During the follow-up, two patients were unaccounted for, local recurrence occurred in three patients, five succumbed and complications were observed in sixteen. The patient's VAS score changed from 7.4 preoperatively to 7.6, 2.3, 2.0, 1.2, 1.5, 1.4 and 2.5 at 24 h, 1, 3, 6, 12, 24 and 36 months after the procedure, respectively. Good local control and significant pain relief after 125I seed implantation was observed in patients with inoperable RSTS. Thus, the present results suggest that this method could be an effective treatment option for patients with inoperable RSTS.

Retroperitoneal liposarcoma: the role of adjuvant radiation therapy and the prognostic factors

PURPOSE

To evaluate the benefit of adjuvant radiation therapy (RT) for retroperitoneal liposarcoma (RPLS) following gross tumor removal.

MATERIALS AND METHODS

We reviewed 77 patients with primary RPLS surgically treated between January 2000 and December 2013. Cases with gross residual disease were excluded. Tumor grade was evaluated according to the French Federation of Cancer Centers Sarcoma Group (FNCLCC) system. Adjuvant RT was delivered to 32 patients (42%) using external beam RT alone. Median follow-up time was 36 months (range, 5 to 169).

RESULTS

Among 77 patients, 33 (43%) presented with well-differentiated, 31 (40%) with de-differentiated, 8 (10%) with myxoid/round and 4 (5%) with pleomorphic morphology. The RT group included less well-differentiated subtype than surgery group (28% vs. 53%). During follow up, 34 patients (44%) showed local recurrence. Local recurrence rate was lower in the RT group (38%) compared to the surgery group (49%). The 3-year local control rate (LC) was 55.6%, and the 3-year overall survival (OS) was 82.1%. Tumor histology and FNCLCC grade were significantly associated with local recurrence. There was no statistical significance of adding adjuvant RT in LC (p = 0.312). However, patients with tumor histology other than well-differentiated subtype showed marginally decreased local recurrence rate after adjuvant RT (3-year LC, RT 43.9% vs. no RT 35.3%; p = 0.087).

CONCLUSION

RPLS patients receiving RT experienced less local recurrence. We suggest that the addition of adjuvant RT may be related to improvement of LCs, especially in patients with non-favorable histologic subtypes.

Practical Issues for Retroperitoneal Sarcoma

Background

Retroperitoneal sarcoma is rare. Using initial specimens on biopsy, a definitive diagnosis of histological subtypes is ideal but not always achievable.

Methods

A retrospective institutional review was performed for all cases of adult retroperitoneal sarcoma from 1996 to 2015. A review of the literature was also performed related to the distribution of retroperitoneal sarcoma subtypes. A meta-analysis was performed.

Results

Liposarcoma is the most common subtype (45%), followed by leiomyosarcoma (21%), not otherwise specified (8%), and undifferentiated pleomorphic sarcoma (6%) by literature review. Data from Moffitt Cancer Center demonstrate the same general distribution for subtypes of retroperitoneal sarcoma. A pathology-based algorithm for the diagnosis of retroperitoneal sarcoma is illustrated, and common pitfalls in the pathology of retroperitoneal sarcoma are discussed.

Conclusions

An informative diagnosis of retroperitoneal sarcoma via specimens on biopsy is achievable and meaningful to guide effective therapy. A practical and multidisciplinary algorithm focused on the histopathology is helpful for the management of retroperitoneal sarcoma.

Oncology outcomes in Retroperitoneal sarcomas: Prognostic factors in a Retrospective Cohort study

INTRODUCTION

Retroperitoneal sarcomas are a rare group of malignant soft tissue tumors with a generally poor prognosis. The aim of the study was to define the demographic characteristics and prognostic factors for patients with retroperitoneal sarcomas (RPS) in a Tertiary Referral Center at Mexico.

METHODS

A retrospective study of patients with RPS treated from January 2005 to December 2012 at the National Cancer Institute at Mexico. Patient, tumor and treatment variables were analyzed including use of adjuvant therapy and survival status. Survival and local recurrence curves were estimated using the Kaplan-Meier method.

RESULTS

Ninety-five patients with a mean age of 47 years with retroperitoneal sarcoma were included. Median follow-up was 25 months (range 1-108 months). The average tumor size was 23.7 cm. Histology, 58 (61.1%) were liposarcoma, 14 (14.7%), leiomyosarcomas and 23 (24.2%) were from other histologies. In 64 (67.4%) patients were high-grade malignancies. The median survival was 51 months for patients with complete resection, 25.1 months for those with incomplete resection, and 4.4 months for those with unresectable tumors. Complete resection (p = 0.0001), and liposarcoma (p = 0.03) were prognostic factors for overall survival.

CONCLUSION

In this study of patients with retroperitoneal, complete resection and liposarcoma histology are prognostic factors related to the disease-free and overall survival. Patients approached with curative intent should undergo aggressive attempts at complete surgical resection.

Dedifferentiated Liposarcoma of Retroperitoneum With Extensive Osteosarcomatous Component

Dedifferentiated liposarcoma (DDLS) is a rare subtype of liposarcoma composed of 2 components: a well-differentiated liposarcoma (WDLS) and a nonlipogenic sarcoma (dedifferentiation component), represented in &gt;90% of cases by a high grade undifferentiated pleomorphic sarcoma, in the form of both small microscopic foci and/or grossly recognizable nodular masses. The paper reports a rare case of a retroperitoneal DDLS, in which approximately half of a tumor mass is composed of a high-grade osteosarcoma. A 68-year-old Caucasian woman affected by abdominal discomfort. Clinical examination showed a large, hard and fixed abdominal mass. Computed tomography scan revealed a huge retroperitoneal mass composed of 2 distinct components: the upper part showed a hypodense tissue, while the lower part showed a higher density and coarse calcifications. Patient underwent to a challenging surgical resection of the mass that, at histological examination, resulted to be a DDLS, in which a WDLS coexisted with an osteosarcoma. Presurgical diagnosis of DDLS is difficult due to the great morphologic variability of the dedifferentiated component, ranging from low to high-grade nonlipogenic sarcoma. The present case contributes to widen the morphological spectrum of DDLS, emphasizing the possibility that a retroperitoneal mass with a dual tissue component, one of which containing extensive areas with coarse calcifications, is highly suspected to be a DDLS with an osteosarcomatous component. This pre-operative finding should alert the surgeon because it has a significant impact on prognosis, increasing the risk of local recurrence and of death by disease in a few months after diagnosis.

The importance of surgical margins in retroperitoneal sarcoma

Surgery is the "gold-standard" treatment for retroperitoneal sarcomas, but local recurrence is common, and can cause disease-related death. Complete gross resection is associated with improved survival, but debate exists as to whether resection of adjacent organs to improve margins or prescription of neoadjuvant radiation leads to better outcomes. This review summarizes data addressing prognostic value of margin, extent of surgery necessary to optimize treatment of retroperitoneal sarcomas, and role of histology in optimizing therapy.

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.

Routes to diagnosis for sarcoma - Describing the sarcoma patient journey

BACKGROUND

Understanding the route to diagnosis for patients with cancer is important to improve the diagnostic pathway and therefore outcomes. We aimed to investigate routes to diagnosis for patients with sarcoma in England.

METHODS

National patient level datasets relating to 7716 soft tissue and 1240 bone sarcoma patients diagnosed between 2006 and 2008 were analysed. Routes to diagnosis were defined as: "Two Week Wait Referral", "GP Referral", "Other Outpatient", "Inpatient Elective", "Emergency Presentation", "Death Certificate Only" and "Unknown".

RESULTS

Patients with sarcoma are most likely to be diagnosed after "GP Referral" or "Emergency Presentation" and are less likely to be referred under a two week wait compared with other malignancies. Patients with bone sarcoma under 10 or over 80 years of age were more likely to present by emergency routes, as were patients with vertebral column, pelvis or unspecified site tumours and those with Ewing's sarcoma or sarcoma NOS. Patients with soft tissue sarcoma under 19 or over 80 years of age and patients with GI tract tumours were more likely to present by emergency routes. Patients presenting by emergency routes more often had metastases and had lower 1 year survival. Patients from least deprived quintiles more often presented by unknown routes: those from more deprived quintiles more often presented by emergency routes.

CONCLUSION

Routes to diagnosis for sarcoma patients differ from other cancers. Interventions to improve the diagnostic experience should consider the very young and elderly, tumours in abdominal, pelvic or spinal locations and on reducing emergency presentations.

Comparative effectiveness research for sarcoma

Modern multidisciplinary management of sarcoma represents several opportunities for comparative effectiveness research. Focusing on the outcomes of survival, quality of life and cost-effectiveness of care, the current state of the art is summarized. Specialized/regional care for sarcoma and the utility of tumor boards or multispecialty discussion is discussed. Issues related to treatment efficacy and sequencing in relation to chemotherapy, radiation, and surgery as well as margin reporting and surveillance are also discussed. Finally, future avenues of comparative effectiveness research for sarcoma are highlighted throughout the chapter.

A case of myxoid liposarcoma of the retroperitoneum: a challenging tumour for diagnosis and treatment

Retroperitoneal sarcomas are rare neoplasms that account for only 1%-2% of all solid tumors and liposarcomas represent the most frequent histological type. We describe the case of a 44-year-old female with a retroperitoneal myxoid liposarcoma of 22 × 19 × 8 cm in size. The only symptoms were persistent pain and progressive tenderness of the abdomen lasting for two months. The mass was radically excised during laparotomy. CT and MRI were useful to clarify the site of origin of the tumor, relationships with other organs, and planning surgery but final diagnosis was based on histological findings. Here we review the literature about the challenging diagnosis, treatment, and prognostic factors of this disease.

The role of radiation in retroperitoneal sarcomas

OPINION STATEMENT

Retroperitoneal sarcomas form a group of rare malignancies that require expertise in every aspect of management. Patients benefit from referral to cancer centers that can provide comprehensive, multidisciplinary, oncologic management. The role of radiation in retroperitoneal sarcoma management is, appropriately, the subject of considerable controversy due to the absence of high-level evidence proving its efficacy. Nonetheless, the preponderance of available data suggests that radiation therapy likely improves local control and, in some settings, may favorably impact resectability and survival. These outcome observations coupled with the lower doses (45-54 Gy) and normal tissue displacement characteristic of preoperative radiation therapy leads us to favor preoperative radiotherapy followed by oncologic resection for most retroperitoneal sarcomas. This strategy appears to provide the highest chance of safe and successful delivery of multimodal therapy, which can otherwise be hindered by postoperative complications as a result of technically challenging surgery and normal tissue radiation dose tolerances. Dose-escalation and selective integrative boosts to "at-risk" margins are attractive strategies that merit, and arguably require, further clinical evaluation. We believe that postoperative radiotherapy should be reserved for very high-risk cases and should be treated to a dose of ≥60 Gy respecting normal tissue dose tolerances. An additional approach that we consider in the postoperative setting is close surveillance with consideration of preoperative radiotherapy at recurrence before repeat surgical resection. Highly conformal radiotherapy techniques, such as IMRT with image guidance, should be employed to minimize dose to normal tissues and thereby allow delivery of efficacious radiation doses. If feasible, referral to a treatment facility with proton beam therapy should be discussed with the patient, especially if normal tissue dose constraints cannot be met using IMRT/IGRT. Participation in prospective studies should be highly encouraged.

Excellent response of malignant peripheral nerve sheath tumour of retroperitoneum to radiation therapy

Malignant peripheral nerve sheath tumours are high-grade sarcomas originating from Schwann cells or nerve sheath cells. Most of these tumours are associated with major nerves of the body wall and extremities. The lower extremity and the retroperitoneum are the most common sites. Surgery is the cornerstone of treatment, however, radiation therapy is usually used as an adjuvant treatment. In this paper we present a 57-year-old Iranian woman with malignant peripheral nerve sheath tumour of retroperitoneum who was operated subtotally and then underwent radiation therapy which led to disappearance of all gross residual disease.

Blood Loss and Massive Transfusion in Patients Undergoing Major Oncological Surgery: What Do We Know?

Patients with solid malignancies who were not candidates for tumor resections in the past are now presenting for extensive oncological resections. Cancer patients are at risk for thromboembolic complications due to an underlying hypercoagulable state; however, some patients may have an increased risk for bleeding due to the effects of chemotherapy, the administration of anticoagulant drugs, tumor-related fibrinolysis, tumor location, tumor vascularity, and extent of disease. A common potential complication of all complex oncological surgeries is massive intra- and postoperative hemorrhage and the subsequent risk for massive blood transfusion. This can be anticipated or unexpected. Several surgical and anesthesia interventions including preoperative tumor embolization, major vessel occlusion, hemodynamic manipulation, and perioperative antifibrinolytic therapy have been used to prevent or control blood loss with varying success. The exact incidence of massive blood transfusion in oncological surgery is largely unknown and/or underreported. The current literature mostly consists of purely descriptive observational studies. Thus, recommendation regarding specific perioperative intervention cannot be made at this point, and more research is warranted.