Clinical characteristics and surgical outcomes of retroperitoneal tumors: a comprehensive data collection from multiple departments

Comprehensive treatment strategy for improving surgical resection rate of retroperitoneal sarcomas: a histology-specific approach narrative review

Retroperitoneal sarcoma (RPS) represents a rare and heterogeneous group of malignancies, posing significant challenges in evaluation and management. Surgery, the cornerstone of RPS treatment, critically depends on complete resection for a favorable prognosis. The extent of resection is a crucial determinant of local control and survival. This review delves into the evolution of multidisciplinary management of localized RPS, highlighting the imperative to adapt surgical strategies to tumor histology, location, and patient functional status. We explore the principles of compartmental surgery-an extended first-line approach that involves resecting adjacent viscera for wide negative margins-and its effectiveness across different histological subtypes of RPS and more limited resections for other types. Particular emphasis is placed on the heterogeneity of the disease, as various histological subtypes exhibit distinct biological behaviors. This necessitates a shift away from a one-size-fits-all treatment approach. The review analyzes the role of different surgical strategies, focusing on histological type and location. Additionally, the potential benefits of (neo)adjuvant treatments, such as radiotherapy and chemotherapy, are examined, recognizing their specific histological indications and limitations. This comprehensive review consolidates recent data on surgical strategies and complementary therapies, advocating for a personalized approach tailored to histology. As understanding of the molecular and genetic underpinnings of RPS continues to evolve, so will strategies for its effective management, underscoring the need for global collaboration among specialists in this field to enhance our collective knowledge and treatment methodologies.

The value of contrast-enhanced ultrasound in differentiating benign from malignant retroperitoneal masses

OBJECTIVES

To evaluate the value of contrast-enhanced ultrasound (CEUS) perfusion patterns in the differentiation of benign and malignant retroperitoneal masses (RMs).

METHODS

Between 2006 and 2023, 122 consecutive patients with an RM visualizable by B-mode US were investigated additionally with CEUS. On CEUS, the extent of enhancement (classified as marked, reduced, or absent) and the homogeneity of enhancement (HE; classified as homogeneous or inhomogeneous) were evaluated. Subsequently, the malignancy rate according to CEUS perfusion patterns was determined.

RESULTS

On CEUS, marked enhancement was significantly more frequently associated with malignancy than with benignity (p < 0.0001, Fisher's exact test). All lesions with no enhancement were benign. Regarding HE, there was no significant difference between benign and malignant lesions (p = 0.07, Fisher's exact test).

CONCLUSION

On CEUS, marked enhancement in an RM may be indicative of a malignant lesion. Furthermore, absent enhancement can be considered to be an indication of benignity. The use of CEUS can be helpful in the evaluation of the malignancy of retroperitoneal masses.

Leiomyosarcoma of the abdomen and retroperitoneum; a systematic review

Background

Intraabdominal and retroperitoneal leiomyosarcomas are rare cancers, which cause significant morbidity and mortality. Symptoms, treatment and follow up differs from other cancers, and proper diagnosis and treatment of intraabdominal and retroperitoneal leiomyosarcomas is of utmost importance. We performed a systematic review to collect and summarize available evidence for diagnosis and treatment for these tumours.

Methods

We performed a systematic literature search of Pubmed from the earliest entry possible, until January 2021. Our search phrase was (((((colon) OR (rectum)) OR (intestine)) OR (abdomen)) OR (retroperitoneum)) AND (leiomyosarcoma). All hits were evaluated by two of the authors.

Results

Our predefined search identified 1983 hits, we selected 218 hits and retrieved full-text copies of these. 144 studies were included in the review.

Discussion

This review summarizes the current knowledge and evidence on non-uterine abdominal and retroperitoneal leiomyosarcomas. The review has revealed a lack of high-quality evidence, and randomized clinical trials. There is a great need for more substantial and high-quality research in the area of leiomyosarcomas of the abdomen and retroperitoneum.

Systematic Review Registration

PROSPERO, identifier, CRD42023480527.

Advancements in Diagnosis and Multimodal Treatment Strategies for Retroperitoneal Tumors: A Comprehensive Review

Retroperitoneal tumors (RPTs) encompass both benign and malignant entities, constituting ~0.1% to 0.2% of all malignant tumors, of which 70% to 80% manifest malignancy. Predominantly, retroperitoneal sarcomas (RPS) represent the most prevalent subtype among RPT. With over 70 histologic forms identified, liposarcomas and leiomyosarcomas emerge as the primary constituents of RPS. Accurate diagnosis of RPTs necessitates preoperative core-needle biopsy and comprehensive imaging assessment. The current staging protocol for RPS relies on the eighth edition of the American Joint Committee on Cancer/TNM classification. Surgical excision remains the established gold standard for treating RPS. Therapeutic approaches vary according to the underlying pathophysiology. Although chemotherapy and radiotherapy exhibit efficacy in managing metastatic and recurrent unresectable RPS, their role in primary RPS remains unresolved, necessitating further clinical trials for validation. Concurrently, ongoing research explores the potential of targeted therapies and immunotherapy. This literature review aims to provide a comprehensive overview of existing research, delineating diagnostic pathways and optimal therapeutic strategies for RPT.

Indocyanine green fluorescence imaging-assisted laparoscopy resection of retroperitoneal tumors in children: case report and literature review

This study examined the applicability of indocyanine green (ICG) fluorescence imaging to assist the laparoscopic resection of retroperitoneal tumors in pediatric patients via an abdominal approach. Conducted prospectively at the Guangzhou Women and Children's Medical Center from May to September 2023, the research included three pediatric cases, for whom laparoscopic retroperitoneal tumor resections were performed utilizing ICG fluorescence imaging. In each case, ICG was intravenously administered (0.3 mg/kg) prior to surgery, enabling the visualization of vital vascular structures through real-time fluorescence imaging. The trocar's placement was guided by a "four-hole" technique from the healthy side in a 70-degree lateral decubitus position. The operations were accomplished successfully without any complications. Pathological analysis of the patients identified one case of Wilms tumor of the embryonal type, one ganglioneuroblastoma of the mature type without N-MYC gene amplification, and one mature cystic teratoma. The findings suggest that with careful patient selection and skilled surgical execution, the utilization of ICG fluorescence imaging in the laparoscopic resection of retroperitoneal tumors is both safe and effective in children. This approach significantly improves the visualization of critical blood vessels, thus enhancing surgical safety.

What is the association of preoperative biopsy with recurrence and survival in retroperitoneal sarcoma? A systematic review by the Australia and New Zealand Sarcoma Association clinical practice guidelines working party

Preoperative biopsy for retroperitoneal sarcoma (RPS) enables appropriate multidisciplinary treatment planning. A systematic review of literature from 1990 to June 2022 was conducted using the population, intervention, comparison and outcome model to evaluate the local recurrence and overall survival of preoperative biopsy compared to those that had not. Of 3192 studies screened, five retrospective cohort studies were identified. Three reported on biopsy needle tract seeding, with only one study reporting biopsy site recurrence of 2 %. Two found no significant difference in local recurrence and one found higher 5-year local recurrence rates in those who had not been biopsied. Three studies reported overall survival, including one with propensity matching, did not show a difference in overall survival. In conclusion, preoperative core needle biopsy of RPS is not associated with increased local recurrence or adverse survival outcomes.

Spot scanning proton therapy for unresectable bulky retroperitoneal dedifferentiated liposarcoma: a case report

The development of effective treatment strategies for unresectable retroperitoneal sarcoma is desirable. Herein, we suggest that definitive proton therapy (PT) could be a promising treatment option, regardless of the large size of the tumor. A 52-year-old man presented with a discomfort of the lower abdomen. Computed tomography revealed a retroperitoneal tumor, measuring over 20 cm in the largest dimensions, which was surrounded by the gastrointestinal (GI) tract. Biopsy revealed dedifferentiated liposarcoma. Neoadjuvant chemotherapy was ineffective, and the tumor was ultimately deemed unresectable. The patient opted to receive PT instead of continuation of chemotherapy. Spot scanning PT (SSPT) at a total dose of 60.8 Gy (relative biological effectiveness) in 16 fractions was employed. SSPT administered a dose to the tumor while successfully sparing the surrounding GI tract. He did not receive any maintenance systemic therapy after PT. The tumor gradually shrunk over more than 7 years, with no evidence of recurrence outside the irradiation field. The initial measurable tumor volume of 2925 cc decreased to 214 cc at the final follow-up, seven and a half years after PT. The patient is alive without any severe complications.

Recurrence of locally invasive retroperitoneal dedifferentiated liposarcoma shortly after surgery: A case report and literature review

RATIONALE

Retroperitoneal dedifferentiated liposarcoma (RPDDL) is an uncommon malignancy, which often remains undetected for many years due to having adequate space in the retroperitoneal cavity and lacking clinical manifestations in the early stage of the disease. Surgical procedure is usually used as the first choice for treatment. However, it is prone to local recurrence after the operation, resulting in an unfavorable prognosis. Our aim is to draw useful lessons from the new case and provide some experience for management of the disease.

PATIENT CONCERNS

We describe a 55-year-old male patient who was admitted for a 3-week history of persistent dull ache of the left waist. A large mass of the left upper abdomen was palpated in physical examination. Moreover, the imaging examination revealed that the diameter of the mass was about 21 cm, and some adjacent vital organs were invaded, which brought great challenges to complete surgical resection.

DIAGNOSIS

The postoperative pathological results confirmed that the mass was RPDDL with invasion of the surrounding vital structures including pancreas, spleen, left adrenal gland, left kidney, and vasculature with tumor emboli.

INTERVENTIONS

Surgical resection of the mass was performed by our multidisciplinary team. The patient received chemotherapy 1 month after surgery.

OUTCOMES

The effect of chemotherapy seemed to be unsatisfactory. Local multifocal recurrence of the tumor was considered about 2 months after surgery. Finally, he gave up any treatments and died of the disease.

LESSONS

Regular physical examination and ultrasound screening may detect the disease as early as possible, especially for high-risk group aged 60 to 70, which should be popularized. Incomplete resection, vascular invasion, and interruption of postoperative treatment may lead to an unfavorable prognosis. Therefore, we think that patients with the disease may benefit from complete surgical resection and uninterrupted adjuvant therapy.

Preoperative differentiation of mediastinum and retroperitoneum ganglioneuroma from schwannoma with clinical data and enhanced CT: developing a multivariable prediction model

AIM

To develop a multivariable prediction model for preoperative differentiation of ganglioneuroma (GN) from schwannoma in mediastinum and retroperitoneum based on clinical data and enhanced computed tomography (CT).

MATERIALS AND METHODS

This was a retrospective diagnostic study. Patients diagnosed with mediastinum or retroperitoneal GN or schwannoma at Zhongshan Hospital between July 2006 and March 2022 were divided into a training cohort and a validation cohort at a ratio of 7:3. Clinical information and CT features were collected. Histopathology was the reference standard for diagnosis. The model was developed using binary logistic regression. The predictive performance of the model was assessed using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

RESULTS

A total of 105 patients (47 men and 58 women; mean age of 41 ± 15 years) were enrolled. There were significant differences in symptoms (p=0.006), location (p=0.008), ratio of the craniocaudal diameter (CC) to the major axis on axial images (CC/M; p=0.025), ratio of the CC to the diameter on axial images (CC/D; p<0.001), density homogeneity (p=0.001), enhancement homogeneity (p<0.001), enhancement degree (p<0.001), venous phase CT attenuation value (V; p=0.011), and blood vessels changes (p=0.045) between GN and schwannoma. The area under the ROC curve (AUC) and accuracy in the validation cohort were 0.841 (95% confidence interval [CI] 0.672, 1.000) and 0.839 (95% CI: 0.674, 0.929), respectively. Calibration curves and DCA showed that the model was beneficial for patients.

CONCLUSION

The multivariable prediction model exhibited good predictive performance and may facilitate preoperative planning.

Survival Outcome of Retroperitoneal Sarcomas Treated With a Surgery-First Approach: A Single-Center Experience

Background Retroperitoneal sarcomas (RPS) are rare and complex tumors originating from the retroperitoneal space, an anatomical region nestled behind the abdominal cavity and shielded by the posterior abdominal wall. Late clinical presentation is a hallmark of retroperitoneal sarcomas. The symptoms are often nonspecific, and nodal metastases are rare. Computed tomography (CT) remains the investigation of choice, and a preoperative biopsy is usually not needed. Surgical resection remains the mainstay of treatment, along with adjuvant radiation and chemotherapy. Survival rates are in general poor, even after complete resection. In this study, we attempt to shed some light on the clinicopathological profiling of retroperitoneal sarcomas and their survival outcomes. Objective The objective of this study is to assess the demographic, clinical, and pathological profiling of patients with retroperitoneal sarcoma and to study the survival of patients with retroperitoneal sarcoma. Methodology We conducted a hospital-based retrospective observational study in a tertiary care center in South India between January 2011 and January 2021. We included all patients with histopathologically proven retroperitoneal sarcoma. Metastatic cases and those who underwent chemotherapy or radiation prior to presentation were excluded. Their demographics, pathological reports, and survival were followed up and collected, and statistical analysis was done. Results The study included 16 cases with retroperitoneal sarcomas across the decade in which the data was collected, confirming the rarity of the tumor, out of which more than 40% of patients were above the age of 60. The most common symptom was found to be a bloating sensation in nine patients, followed by abdominal pain in three patients. Seventy-five percent of the patients were found to have a T4 (i.e., a size of more than 15 cm) tumor at presentation. Well-differentiated liposarcoma was found to be the most common pathological variant accounting for 25% of the cases. The mean survival was found to be 8.05 years, which dropped to 5.74 years in Grade 3 tumors. Conclusion Retroperitoneal sarcomas are rare tumors of which liposarcoma is the most common variant. A significant reduction in the mean survival was identified in Grade 3 sarcomas compared to the cumulative survival time of Grade 1 and Grade 2 retroperitoneal sarcomas.

Retroperitoneal capillary arteriovenous malformation mimicking a malignant neoplasm

Introduction

Retroperitoneal tumors account for 0.2% of all neoplasms. Among these tumors, retroperitoneal vascular malformations are particularly rare, with most previously reported cases being venous malformations.

Case presentation

A 72-year-old woman was diagnosed with a retroperitoneal tumor on abdominal computed tomography. The 27-mm diameter tumor was located away from the right kidney and major vessels in the right perirenal adipose tissue. Contrast-enhanced computed tomography revealed a heterogeneously enhanced tumor with well-defined borders. Dynamic contrast-enhanced magnetic resonance imaging revealed rapid enhancement in the arterial phase and a progressive filling-in pattern in the delayed phase. Although vascular malformation was suspected, a definitive diagnosis could not be established. The retroperitoneal tumor was excised laparoscopically for therapeutic and diagnostic purposes, and the histopathological diagnosis confirmed it as a capillary arteriovenous malformation.

Conclusion

Herein, we presented a rare case of retroperitoneal capillary arteriovenous malformation that was difficult to definitively diagnose preoperatively.

Retroperitoneal Sarcomas: a Current Review on Management

Retroperitoneal sarcomas are heterogeneous tumours with variable disease biology and outcomes. The prognosis is primarily related to tumour histology and grade as well as the ability to achieve margin negative resection. Surgery involves compartment or contiguous organ resection to achieve the above goal. Careful utilization of neoadjuvant and adjuvant strategies like radiotherapy and/or chemotherapy can lead to improvement in margin status, thereby contributing to better local control and possibly reducing systemic dissemination. Use of targeted therapies has paved newer pathways of treatment integration centred on molecular and genetic targets. The aim of this review is to update the reader on all aspects of retroperitoneal sarcoma management including emphasis on pertinent and landmark trials in this regard.

Aggressive and frequent resection of recurrences in retroperitoneal sarcoma contributes to long-term survival

PURPOSE

Retroperitoneal sarcoma (RPS) is a rare tumor with a poor prognosis and is often undetected until it is significantly enlarged. While surgical resection remains the primary treatment, there is little research on its benefits, especially that concerning the reoperation of recurrent disease. This study investigated the impact of surgical procedures, especially reoperation of recurrent RPS, on prognosis.

METHODS

This retrospective study included 51 patients who underwent radical resection surgery (R0 status) for primary or recurrent RPS without distant metastasis. Patient outcomes and prognosis were defined in terms of the clinicopathologic factors and surgical techniques performed.

RESULTS

In all cases, the 5-year disease-free survival (DFS) rate was 28.2%, 5-year overall survival rate was 89.9%, and 5-year no residual liposarcoma rate was 54.3% after operation and re-reoperation. There was a statistically significant difference between the 5-year DFS rate and 5-year no residual liposarcoma rate due to frequent re-reoperation (p = 0.011). On univariate analysis of primary and recurrent lesions, the histological type and the number of organs involved were identified as statistically significant prognostic factors. Patients with well-differentiated liposarcomas had a statistically better prognosis than those with other cancer types (primary RPS, p = 0.028; recurrence, p = 0.024).

CONCLUSIONS

Aggressive and frequent resection of recurrent RPS with combined resection of adjacent organs contributes to long-term survival. The establishment of a surgical strategy for RPS will require a prospective study.

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.

A case of retroperitoneal dedifferentiated liposarcoma successfully treated by neoadjuvant chemotherapy and subsequent surgery

Background

Retroperitoneal liposarcoma (RPLS) is the most commonly observed soft tissue sarcoma in the retroperitoneal space. Although the beneficial effect of chemotherapy for RPLS is controversial, there are some reports that have shown a considerable tumor-suppressive effect of chemotherapy in RPLS. We demonstrate a case of dedifferentiated RPLS, which was initially considered inoperable but was successfully treated by neoadjuvant chemotherapy and subsequent curative resection.

Case presentation

A 59-year-old female was referred to our hospital with a chief complaint of right lower quadrant abdominal pain. Abdominal computed tomography revealed a large retroperitoneal tumor with a maximum diameter of 11 cm. The tumor involved retroperitoneal major vasculatures, such as the right common iliac vein and artery, as well as the right psoas muscle and femoral nerve. The right ureter was also involved and obstructed by the tumor. A biopsy was performed through the retroperitoneal route, and the tumor was diagnosed as a dedifferentiated liposarcoma with the Fédération Nationale des Centres de Lutte Contre le Cancer grade 3. Because the tumor was highly invasive and complete resection was not feasible, we decided to administer neoadjuvant chemotherapy with doxorubicin and ifosfamide (AI). After completing 6 courses of AI, the tumor size was considerably reduced, and we decided to perform surgery with curative intent. Before laparotomy, femoro-femoral arterial bypass was performed to prepare for the right common iliac artery resection. Thereafter, the patient underwent laparotomy and tumor resection combined with right nephrectomy, resection of the right common iliac artery and vein, and resection of the right psoas muscle and femoral nerve. The postoperative course was uneventful, although the patient needed a walking brace to support her gait. The pathological findings indicated a 99% disappearance of tumor cells. The patient was healthy without any complaints after 1 year of surgery, and a follow-up CT scan revealed no tumor recurrence.

Conclusions

To the best of our knowledge, this is the first report that showed a nearly complete pathological response to AI in dedifferentiated RPLS, which was subsequently completely resected.