Incidence and Adverse Prognostic Implications of Histopathologic Organ Invasion in Primary Retroperitoneal Sarcoma

A case report of retroperitoneal liposarcoma

BACKGROUND

Retroperitoneal liposarcoma is a rare and complex tumor originating from the mesenchymal tissues, with no specific manifestations in the early stage, and a large tumor size in the late stage. Patients often consult a physician because of large abdominal mass, increased abdominal circumference, and abdominal pain, and rarely because of leukocytosis.

PATIENT CONCERNS

A 54-year-old female presented to our hospital with complaints of "abdominal distension for over 3 months, left lumbar pain for over 2 months." Considering the comprehensive symptoms, examinations, computed tomography scans, and pathological results, the possibility of retroperitoneal liposarcoma is high.

DIAGNOSES

Retroperitoneal liposarcoma with leukocytosis.

INTERVENTIONS

Open retroperitoneal mass excision along with transcystoscopic left ureteral Double-J Ureterl Stent Insertion tube placement and left nephrectomy.

OUTCOMES

The postoperative pathological findings of the abdominal mass, combined with morphological and immunohistochemical results, are consistent with retroperitoneal liposarcoma. The patient had no recurrence in 7 months of postoperative follow-up conducted on the telephone and is now in continued follow-up.

CONCLUSION

Retroperitoneal liposarcoma is highly malignant and prone to recurrence. Radical surgery is currently the primary treatment modality for patients with this condition. Analogous to cancer patients, those with elevated white blood cell counts and retroperitoneal liposarcoma may have poor prognoses, with a high likelihood of local recurrence and distant metastasis. Close postoperative follow-up is necessary. Therefore, regular postoperative review of blood routine may be a relatively economical and convenient method for the early detection of recurrence and metastasis of retroperitoneal liposarcoma.

Vena cava leiomyosarcoma surgery results in a retrospective cohort of 41 patients from two centers

BACKGROUND

Leiomyosarcoma of the vena cava (LMS-VC) is a rare entity with poor oncological outcomes and a lack of histological staging prognostic factors.

METHODS

Outcomes of consecutive patients operated on LMS-VC between March 2003 and May 2022, in two specialized sarcoma centers were reported.

RESULT

Forty-one patients were identified. Median size of LMS-VC was 9 cm with 68% of complete obstruction. After surgery, severe complication rate was 30%. No postoperative mortality was reported. Microscopic complete excision was obtained for 71% of patients, R1 for 27% and one patient presented an R2 resection. Grade 3 was found in 24%. After a median follow-up of 70 months, 3 years disease-free survival (DFS) and 5 years DFS were 34% and 17%, and 3 years overall survival (OS) and 5 years OS were 74% and 50%. Distant metastasis concerned 54% of recurrences, local 7% and local and distant 5%. Multivariate analysis showed that FNCLCC grade (p < 0.001) and perioperative chemotherapy (p = 0.026) were significant factors for DFS. In multivariate analysis, FNCLCC grade was a significant factor for OS (p = 0.004).

DISCUSSION

Perioperative chemotherapy may have a role to play in lowering the risk of recurrence for LMS-VC, particularly in high-grade tumor.

Standardizing Surgical Management of Retroperitoneal Sarcomas: Dawn of a New Surgical Subspeciality in India

BACKGROUND

Retroperitoneal sarcomas are a complex and heterogenous group of tumors. An approach to these tumors should be guided by a clear understanding of the disease biology and anatomical principles, which mandates a dedicated multidisciplinary team approach at all steps of management. We present our experience of evolution as a high-volume sarcoma center with a dedicated multidisciplinary tumor board (the RP clinic) with consequent standardization of surgeries and management protocols.

METHODS

A retrospective analysis of a prospectively maintained database for patients undergoing surgery from January 2011 to June 2023 was performed. Data were divided into the pre-clinic era (2011-2017) and post-clinic era (2018-2023). Survival curves were obtained using the Kaplan-Meier method, and the Chi-square test was used to test significance for categorical variables. Time trends were analyzed using the one-way analysis of variance (ANOVA) test. A p value ≤ 0.05 was considered significant.

RESULTS

Overall, 254 patients were operated during this period; 36.6% of patients underwent surgeries in the pre-RP clinic era (6 years) and 63.3% in the post-RP clinic era (4.5 years). There was a statistically significant increase in the number of cases being operated per year, from an average of 16.3 in the pre-clinic era to 42.4 in the post-RP clinic era (p = 0.001). The post-RP clinic era also showed a significant increase in compartment and multivisceral resections (49% vs. 18.2%; p = 0.0001).

CONCLUSIONS

Establishment of a dedicated multidisciplinary tumor board (RP clinic) resulted in standardization of management protocols, resulting in optimal oncological and surgical outcomes.

Analysis of recurrence and metastasis patterns and prognosis after complete resection of retroperitoneal liposarcoma

Objective

To analyze the recurrence and metastasis patterns and prognosis after complete resection of retroperitoneal liposarcoma.

Methods

The clinical postoperative follow-up data and results of patients who underwent complete resection of retroperitoneal liposarcoma from September 10, 2014, to September 8, 2021, at Hebei Medical University hospital were collected retrospectively.

Results

A total of 60 patients with complete resection of retroperitoneal liposarcoma, including 33 cases of retroperitoneal liposarcoma recurrence, 2 cases of liver metastasis, and 1 case of lung metastasis, were included. The results showed that 100% of the recurrent sites were located in the primary region of the tumor, with most recurrences located near the kidney, paracolic sulci, and iliac vessels. Three patients had distant metastasis without obvious recurrence on imaging examination. The pathological type of retroperitoneal liposarcoma, Ki67 expression, and presence of serum albumin were risk factors for recurrence and metastasis after complete resection of retroperitoneal liposarcoma. The malignancy and Ki67 expression were independent risk factors for recurrence and metastasis as well as for overall survival of patients undergoing complete resection of retroperitoneal liposarcoma.

Conclusion

Complete resection remains the most effective method to treat retroperitoneal liposarcoma. Patients with pathological types of retroperitoneal liposarcoma showing dedifferentiation, pleomorphism, mixed type, and high Ki67 expression should be closely monitored and observed after complete resection, especially for imaging changes in the primary tumor area.

Organ Infiltration and Patient Risk After Multivisceral Surgery for Primary Retroperitoneal Liposarcomas

BACKGROUND

The extent of histological organ involvement (HOI) to organs and structures of a retroperitoneal liposarcoma may have prognostic implications. This study investigated incidence, characteristics, and risk association of HOI in these patients.

PATIENTS AND METHODS

Data of patients who underwent multivisceral resection for primary liposarcoma (2009-2014) were retrospectively analyzed. HOI was the variable of interest and was classified into four degrees: absent (HOI-0), perivisceral (HOI-1), initial (HOI-2), and advanced (HOI-3). Primary endpoint was overall survival (OS). Secondary endpoint was disease-free survival (DFS). The prognostic value of HOI was adjusted for preoperative treatment and the Sarculator nomogram score.

RESULTS

A total of 109 patients were included. HOI-0, HOI-1, HOI-2, and HOI-3 were detected in 9 (8.3%), 11 (10.1%), 43 (39.4%), and 46 (42.2%) patients. Median follow-up was 8.4 years [interquartile range (IQR) 7.2-9.6 years]. There were 68 recurrences and 50 patient deaths observed, resulting in a 10-year OS and DFS of 51.1% [95% confidence interval (CI) 41.9-62.1%] and 34.1% (95% CI 25.2-46.1%), respectively. Clinically relevant HOIs (HOI-2 and HOI-3) were found in 35/45 (77.8%) and 54/64 (84.4%) cases of well- and de-differentiated liposarcomas, respectively. On multivariable survival analysis, patients with HOI-3 had significantly shorter OS (HOI-3 vs HOI-0/HOI-1 HR 2.92; p = 0.012) and DFS (HOI-3 vs HOI-0/HOI-1 HR 2.23; p = 0.045), independently of the nomogram score (OS: HR 2.93; p < 0.001; DFS: HR 1.78; p = 0.003).

CONCLUSIONS

Initial and advanced HOIs are frequently detected in both well-differentiated and de-differentiated liposarcomas, supporting that multivisceral resection may be needed. HOI stratifies the risk of patients with primary retroperitoneal liposarcoma.

Deciding individual treatment for primary retroperitoneal sarcoma

INTRODUCTION

Retroperitoneal sarcomas (RPS) are rare mesenchymal tumors that account for only 0.1-0.2% of all malignancies. Management of this disease is challenging, and resection remains the cornerstone of treatment. Ongoing international collaboration has expanded our knowledge of this disease, allowing for a more personalized approach to RPS patients resulting in improved survival over time. Due to the heterogeneity of RPS, with differing recurrence patterns and sensitivities to neoadjuvant therapies based on histology and grade, management of RPS should be tailored to the individual patient.

AREAS COVERED

Our review focuses on a histology-driven approach in the management of primary RPS. We searched relevant articles from 1993 to 2023 that investigated prognostic factors and treatment of patients with RPS and summarized recent advances and future directions in the field.

EXPERT OPINION

Deeper understanding of the role of neoadjuvant radiotherapy and ongoing trials investigating the role of neoadjuvant chemotherapy will potentially contribute to the development of individualized treatment pathways.

Survival analysis and prognostic factors of retroperitoneal liposarcoma curative surgery in a single centre. Analysis of adjacent organ invasion between imaging and definitive histopathology

INTRODUCTION

Retroperitoneal liposarcoma (RPL) is a rare primary mesenchymal tumour that develops in retroperitoneal adipose tissue. Unlike the majority of published series, this homogeneous cohort focuses on RPL. The main purpose of this study is to evaluate the overall and recurrence-free survival of RPLs who underwent excision surgery and the prognostic factors involved.

PATIENTS AND METHODS

A total of 82 patients from a single centre, who underwent curative surgery for histologically confirmed retroperitoneal liposarcoma between 2008 and 2020, were analysed in the study. Compartmental surgical excision was advised as per the guidelines. The primary endpoints were 5 years of overall survival and recurrence-free survival. Predictable tumour invasion of adjacent organs, based on a pre-operative CT scan, was also investigated to test the correlation between pre-operative imaging and pathological data.

RESULTS

Median follow-up was 61.6 months. Five year overall survival was 71.9% [95% CI: 59.8; 80.9] and 5 year recurrence-free survival was 49% [95% CI: 36.4; 60.5]. Following multivariable analysis, the factors influencing overall survival were tumour rupture and onset of severe complications (Dindo-Clavien grade ≥3). Factors influencing recurrence-free survival were neoadjuvant radiotherapy and tumour rupture. A significant correlation (p < 0.05) was found between predicted invasion based on a CT scan of the colon, spleen, adrenal gland, posterior abdominal wall and diaphragm, and pathological invasion.

CONCLUSIONS

Curative compartmental surgery remains the gold standard treatment for RPL. This study, highlights the fact that the quality of the surgical excision is a crucial factor in patient prognosis.

Histology-tailored multidisciplinary management of primary retroperitoneal sarcomas

Until recently, the recommendation for primary retroperitoneal sarcomas (RPS) was to perform a complete en-bloc gross excision, (neo) adjuvant treatments being options which were not validated by randomized studies, with a large discrepancy of use between centers. The heterogeneity of RPS, with their different biological behaviour, renders a homogenous therapeutic and surgical approach probably inappropriate. Recent studies, both surgical and dedicated to adjuvant treatments, allow refining these recommendations. This review summarizes recent advances and directions.

Special clinical scenarios in RPS: Involvement of great vessels and pancreas and penetration across natural foramina

The primary treatment for retroperitoneal sarcomas is surgery. This requires a carefully planned, typically multivisceral, resection. A few complex scenarios that may arise include vascular involvement, pancreatic involvement, or herniation of the tumor into another compartment outside of the retroperitoneum. These scenarios must be anticipated before surgery to optimize preoperative preparation, minimize postoperative morbidity and mortality, and improve oncologic outcomes. Our aim is to highlight these clinically challenging anatomic presentations that can be encountered in patients with retroperitoneal sarcomas.

Surgical Management of Retroperitoneal Sarcoma

Surgery is the cornerstone of treatment for retroperitoneal sarcoma (RPS). Surgery should be performed by a surgical oncologist with sub-specialization in this disease and in the context of a multidisciplinary team of sarcoma specialists. For primary RPS, the goal of surgery is to achieve the complete en bloc resection of the tumor along with involved organs and structures to maximize the clearance of the disease. The extent of resection also needs to consider the risk of complications. Unfortunately, the overarching challenge in primary RPS treatment is that even with optimal surgery, tumor recurrence occurs frequently. The pattern of recurrence after surgery (e.g., local versus distant) is strongly associated with the specific histologic type of RPS. Radiation and systemic therapy may improve outcomes in RPS and there is emerging data studying the benefit of non-surgical treatments in primary disease. Topics in need of further investigation include criteria for unresectability and management of locally recurrent disease. Moving forward, global collaboration among RPS specialists will be key for continuing to advance our understanding of this disease and find more effective treatments.

Short- and long-term surgical outcomes of pancreatic resection for retroperitoneal sarcoma: A long-term single-center experience of 90 cases

BACKGROUND AND OBJECTIVES

Resection of retroperitoneal sarcoma (RPS) en bloc with pancreas is challenging and controversial. This single-center retrospective study aimed to analyze the impact of pancreatic resection (PR) and its different types on short- and long-term outcomes in patients with RPS.

METHODS

Data from 242 consecutive patients with RPS who underwent surgical treatment at the Peking University Cancer Hospital Sarcoma Center between January 2010 and February 2021 were analyzed. Out of these, 90 patients underwent PR, including pancreaticoduodenectomy (PD) in 31 and distal pancreatectomy (DP) in 59.

RESULTS

Patients in the PR group had a higher major morbidity (37.8% vs. 14.5%) and mortality (8.9% vs. 1.3%) than those in the non-PR group, with a similar 5-year overall survival (OS) rate (46.9% vs. 53.6%). Patients in the PD and DP groups had a slight difference in major morbidity (48.4% vs. 32.2%), mortality (6.4% vs. 10.2%), and 5-year OS rates (43.3% vs. 49.3%). The PR type was not an independent risk factor for major morbidity or OS.

CONCLUSIONS

PR in RPS resection was associated with increased morbidity and mortality with minimal influence on survival. Patients with RPS undergoing PD and DP showed slight differences in terms of safety and OS.

Giant retroperitoneal liposarcoma measuring 27 × 29 × 36 cm: a case report

Retroperitoneal tumors are rare neoplasms that can reach great dimensions due to a slow growth pattern. Although these tumors rarely metastasize, they have a great risk of recurrence, and majority of times these lesions are a challenge for the surgeon. We report the case of a 63-year-old woman who presented with symptoms of large bowel obstruction and was diagnosed with a large heterogenous mass located in the retroperitoneal space. The fine needle biopsy revealed the histology of liposarcoma. The purpose of this article is to report our approach in management of this kind of tumor. Tumor size (27.1 × 29.1 × 36.1 cm) and involvement to the adjacent organs was a challenge for us in order to reach safe oncological margins. In these cases, the risk of recurrence is high; therefore, the patient should be screened at 6, 12 and 24 months post procedure. Chemotherapy or radiotherapy for this tumor is not yet defined, and if operable, surgery is the treatment of choice.

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.

Surgical Principles of Primary Retroperitoneal Sarcoma in the Era of Personalized Treatment: A Review of the Frontline Extended Surgery

Simple Summary

Surgery is the only curative treatment for localized disease in retroperitoneal sarcoma (RPS). Frontline extended surgery, or compartmental surgery, is a recent surgical strategy consisting of resecting the tumor together with adjacent organs, with the aim of minimizing marginality. This review provides a practical step by step description of this standardized procedure, tailored to histologic behavior, tumor localization, and patient condition.

Abstract

Surgery is the key treatment in retroperitoneal sarcoma (RPS), as completeness of resection is the most important prognostic factor related to treatment. Compartmental surgery/frontline extended approach is based on soft-tissue sarcoma surgical principles, and involves resecting adjacent viscera to achieve a wide negative margin. This extended approach is associated with improved local control and survival. This surgery must be tailored to tumor histology, tumor localization, and patient performance status. We herein present a review of compartmental surgery principles, covering the oncological and technical basis, and describing the tailored approach to each tumor subtype and localization in the retroperitoneum.

Postoperative Outcomes of Distal Pancreatectomy for Retroperitoneal Sarcoma Abutting the Pancreas in the Left Upper Quadrant

Background

En bloc resection of the tumor with adjacent organs is recommended for localized retroperitoneal sarcoma (RPS). However, resection of the pancreas is controversial because it may cause serious complications, such as pancreatic fistula or bleeding. Thus, we evaluated the outcomes of distal pancreatectomy (DP) in pancreas-abutting RPS of the left upper quadrant (LUQ).

Methods

We retrospectively reviewed all consecutive patients who underwent surgery for RPS between September 2001 and April 2020. We selected 150 patients with all or part of their tumor located in the LUQ on preoperative computed tomography. Eighty-six patients who had tumors abutting the pancreas were finally enrolled in our study.

Results

Fifty-three patients (53/86; 61.6%) were included in the non-DP group, and 33 patients (33/86; 38.4%) were included in the DP group. Total postoperative complications and complication rates for those Clavien–Dindo grade 3 or higher were similar between the non-DP group and DP group (p = 0.290 and p = 0.550). In the DP group, grade B pancreatic fistulae occurred in 18.2% (6/33) of patients, but grade C pancreatic fistulae were absent, and microscopic pancreatic invasion was noted in 42.4% (14/33) of patients. During multivariate analysis, microscopic pancreatic invasion was deemed a risk factor for local recurrence (p = 0.029). However, there were no significant differences on preoperative computed tomography findings between the pancreatic invasion and non-invasion groups.

Conclusion

DP is a reasonable procedure for pancreas-abutting RPS located at the LUQ when both complications and complete resection are considered.

Prognostic implications of histological organ involvement in retroperitoneal sarcoma

BACKGROUND

The prognostic significance of histological organ involvement by retroperitoneal sarcoma subtype is unknown. The present study aimed to describe organ involvement across the subtypes, and the implications for survival.

METHODS

Patients undergoing surgery for primary retroperitoneal sarcoma at the Queen Elizabeth Hospital, Birmingham from April 2005 to September 2018 were identified retrospectively. Histological organ involvement was classed as pushing, infiltrative or neither. Univariable and multivariable Cox regression models were produced to analyse the association between histological organ involvement and both overall (OS) and recurrence-free (RFS) survival for the cohort as a whole, and by histological subtype.

RESULTS

Data were available for a total of 197 patients, of whom 171 (86.8 per cent) had at least one organ resected. Infiltrative organ behaviour was seen in 37 patients (18.8 per cent), and pushing behaviour in 67 (34.0 per cent). For the cohort as a whole, infiltration (hazard ratio (HR) 4.32, 95 per cent c.i. 2.35 to 7.93; P < 0.001), but not pushing (HR 1.62, 0.90 to 2.92; P = 0.106), was associated with significantly shorter OS, in comparisons with a group with neither of these behaviours. However, this effect was found to differ significantly by histological subtype (P = 0.009). For patients with dedifferentiated liposarcoma, there was no significant association between tumour behaviour and either OS (P = 0.508) or RFS (P = 0.313). However, in leiomyosarcoma, infiltrative behaviour was associated with shorter OS (P = 0.002), and both infiltrative (P < 0.001) and pushing (P = 0.010) behaviours were associated with shorter RFS, compared with tumours with neither behaviour. Multivariable analyses of both OS and RFS returned similar results.

CONCLUSION

The prognostic implications of organ involvement in retroperitoneal sarcoma vary by histological subtype.

Multidisciplinary Management of Retroperitoneal Sarcoma: Diagnosis, Prognostic Factors and Treatment

Simple Summary

The management of retroperitoneal sarcomas can be challenging due to the variety of their presentation, histopathological types, and behaviours. This literature review provides a comprehensive and practical overview of the management of retroperitoneal sarcomas, focusing on diagnostic challenges, prognostic factors, multidisciplinary aspects of treatment and new research perspectives.

Abstract

Retroperitoneal sarcomas (RPS) are rare cancers whose management can be challenging due to various presentation patterns, multiple organ involvement, and a high local and distant recurrence rate. Histopathology and prognostic factors analysis are essential to predict the behaviour of the disease and plan the best therapeutic strategy. To date, surgery is still the main therapeutic option that guarantees a chance of cure from the primary disease. While chemotherapy and radiotherapy seem to be good options for controlling metastatic and recurrent irresectable disease, their role in the treatment of primary RPS remains unclear. This literature review aims to provide a comprehensive overview of the multidisciplinary aspects of RPS management in high-volume centres, summarising the diagnostic path, the prognostic factors, and the most suitable therapeutic options.

Oncological outcomes after major vascular resections for primary retroperitoneal liposarcoma

BACKGROUND

The surgical management of retroperitoneal sarcomas frequently involves complex multivisceral resections, however retroperitoneal liposarcoma (LPS) rarely invade major abdominal vessels. The aim of the study was to assess association of major vascular resections with outcome of primary LPS.

METHODS

All consecutive patients who underwent resection at our institutions for primary LPS between 2002 and 2019 were included. A propensity matched analysis was performed, adjusting the groups for the variables of Sarculator, to assess the effect of vascular resection on oncological outcomes.

RESULTS

Overall 425 patients were identified. Twenty-four (5%) patients had vascular resection. At final pathology 18 patients had vascular infiltration, 2 vascular encasement and 4 involvement without infiltration. Vascular resection was associated with longer operative time (480' vs. 330'; p < 0.001) and greater need for transfusions (4 vs. 0 units; p < 0.001), and was burdened by a higher rate of major complications (54% vs. 25%; p = 0.002). After propensity matched analysis, patients undergoing vascular resection had a lower 5-year OS (60% vs. 81%; p = 0.05), and a higher incidence of local and distant recurrence at 5 years (local: 45% vs. 24%, p = 0.05; distant: 20% vs. 0%, p = 0.04).

CONCLUSIONS

Vascular resection is feasible and safe even in the context of multivisceral resection for primary retroperitoneal liposarcomas, although associated to a higher complication rate. However, the independent association between vascular involvement and a higher risk of local recurrence, distant metastases and death may imply a more aggressive biology, which should be factored in the initial management of this complex disease.

Morbidity and Outcomes After Distal Pancreatectomy for Primary Retroperitoneal Sarcoma: An Analysis by the Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group

BACKGROUND

Multi-visceral resection often is used in the treatment of retroperitoneal sarcoma (RPS). The morbidity after distal pancreatectomy for primary pancreatic cancer is well-documented, but the outcomes after distal pancreatectomy for primary RPS are not. This study aimed to evaluate morbidity and oncologic outcomes after distal pancreatectomy for primary RPS.

METHODS

In this study, 26 sarcoma centers that are members of the Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG) retrospectively identified consecutive patients who underwent distal pancreatectomy for primary RPS from 2008 to 2017. The outcomes measured were 90-day severe complications (Clavien-Dindo ≥ 3), postoperative pancreatic fistula (POPF) rate, and oncologic outcomes.

RESULTS

Between 2008 and 2017, 280 patients underwent distal pancreatectomy for primary RPS. The median tumor size was 25 cm, and the median number of organs resected, including the pancreas, was three. In 96% of the operations, R0/R1 resection was achieved. The 90-day severe complication rate was 40 %. The grades B and C POPF complication rates were respectively 19% and 5% and not associated with worse overall survival. Administration of preoperative radiation and factors to mitigate POPF did not have an impact on the risk for the development of a POPF. The RPS invaded the pancreas in 38% of the patients, and local recurrence was doubled for the patients who had a microscopic, positive pancreas margin (hazard ratio, 2.0; p = 0.042).

CONCLUSION

Distal pancreatectomy for primary RPS has acceptable morbidity and oncologic outcomes and is a reasonable approach to facilitate complete tumor resection.

Severe Postoperative Complications are Associated with Impaired Survival in Primary but not in Recurrent Retroperitoneal Sarcoma

BACKGROUND

Retroperitoneal sarcoma (RPS) surgery entails multivisceral resection, which may cause postoperative complications. We assessed the effects of complications on survival to identify their predisposing factors in primary (PRPS) and recurrent (RRPS) RPS.

METHODS

We retrospectively analyzed our institutional database. Severe postoperative complications (SC) were defined as Clavien-Dindo classification ≥ 3. Predisposing factors for complications were investigated, as was their effect on long-term outcomes.

RESULTS

In total, 154 RPS resections (78 PRPS and 76 RRPS) performed between January 2008 and December 2018 were included. Neoadjuvant chemotherapy and multifocal tumors were more common in RRPS than PRPS (34.2% vs. 11.3%, P = 0.001 and 42.1% vs. 10.3%, P < 0.001, respectively). Although surgical extent in RRPS was limited compared with PRPS (weighted organ score 1 vs. 2, P = 0.01; transfusion requirement 23.6% vs. 35.8%, P = 0.04), SC and mortality rates were comparable. SC rates were 30.1% and 35.5% for PRPS and RRPS, respectively. NACT rate tended to be higher in PRPS patients with SC (20.8% vs. 7.4%, P = 0.09), whereas weighted organ score and transfusion requirement were increased in RRPS patients with SC (2 vs. 1, P = 0.01; 40.7% vs. 14.3%, P = 0.009, respectively). PRPS patients with SC had decreased overall survival (35 months, 95% confidence interval [CI] 12.2-57.7) compared with those without SC (90 months, 95% CI 71.4-108.5, P = 0.01).

CONCLUSIONS

Postoperative complications are associated with impaired outcomes in PRPS but not in RRPS. The negative effects of complications on outcomes should be factored to perioperative management.

Retroperitoneal Sarcomas: Prognostic Factors and Outcomes of a Series of Patients Treated at a Single Institution

Retroperitoneal sarcomas (RPS) are rare heterogeneous tumors arising in the retroperitoneum with unique biological and behavioral patterns that are thought to be closely linked to histology. The aim of the study was to audit our results and analyze various clinico-pathological factors including surgical excision, histology, and their implications on the recurrences and survival outcomes in RPS. Retrospective analysis of patients treated at a tertiary referral center in India from March 2008 to July 2017 was performed. The clinico-pathological variables were analyzed for their association with tumor recurrence and survival with special emphasis on histological subtype. The primary outcome was overall survival (OS). One hundred consecutive patients operated for RPS were analyzed. Of these, 27 were operated for recurrent tumors. Liposarcomas (LPS) and leiomyosarcomas (LMS) constituted 50% (n = 50) and 30% (n = 30) of patients respectively. Complete tumor excision was achieved in 83%, with 43% patients undergoing adjacent organ resection. At a median follow-up of 25.3 months, the median disease-free survival (DFS) and overall survival (OS) were 30 months and 87.8 months respectively. On multivariate analysis, tumor grade was the only factor to significantly affect survival (p = 0.001 for DFS and 0.005 for OS). There was no difference in survival outcomes between infiltrative and adhesive tumors with respect to adjacent organ invasion (p = 0.361 for OS). Tumor grade remains an important prognostic factor affecting disease-free and overall survival in retroperitoneal sarcomas irrespective of tumor size, site, and histology.

Well-differentiated liposarcoma and dedifferentiated liposarcoma: An updated review

Well-differentiated liposarcoma (WDL)/atypical lipomatous tumor and dedifferentiated liposarcoma (DDL) together comprise the largest subgroup of liposarcomas, and constitute a histologic and behavioral spectrum of one disease. WDL and DDL typically occur in middle-aged to older adults, particularly within the retroperitoneum or extremities. WDL closely resembles mature adipose tissue, but typically shows fibrous septation with variable nuclear atypia and enlargement. WDL does not metastasize, but can dedifferentiate to DDL, which is associated with more aggressive clinical behavior, with a greater propensity for local recurrence and the capacity for metastasis. Although distant metastasis is rarer in DDL compared with other pleomorphic sarcomas, behavior is related to location, with a significantly worse outcome in retroperitoneal tumors. DDL typically has the appearance of undifferentiated pleomorphic or spindle cell sarcoma, and is usually a non-lipogenic sarcoma that is adjacent to WDL, occurs as a recurrence of WDL or which can arise de novo. WDL and DDL share similar background genetic aberrations; both are associated with high-level amplifications in the chromosomal 12q13-15 region, which includes the CDK4 and MDM2 cell cycle oncogenes. In addition, DDL harbor further genetic changes, particularly 6q23 and 1p32 coamplifications. While surgical excision remains the treatment mainstay with limited medical options for patients with aggressive recurrent disease or metastases, novel targeted therapies towards the gene products of chromosome 12 are being evaluated. This review summarizes the pathology of WDL and DDL, discussing morphology, immunohistochemistry, genetics and the differential diagnosis.

Tumor Biological Aspects of Epithelial versus Mesenchymal Tumors of the Gastrointestinal Tract

One of the holy grails of cancer surgery for surgical oncologists is to perform a macroscopically complete resection of the affected organ or site with negative microscopic margins. The surgical oncologist must also be mindful of what constitutes appropriately-sized negative margins. However, what is necessary, based on the best available evidence, can vary considerably for different malignancies arising within the same organ. This review compares two different gastric and rectal malignancies, one each of epithelial and of mesenchymal origin. Data supporting extent of margins will be reviewed, illustrating the importance of knowing the histologic diagnosis prior to surgery to provide proper oncologic care.

Current principles of surgery for retroperitoneal sarcomas

Surgery for primary retroperitoneal sarcomas (RPS) often requires a technically challenging, en bloc multivisceral resection to optimize outcomes. Surgery may also be appropriate for patients with localized recurrent RPS. Anatomic considerations and tumor biology driven by histologic subtype may guide the extent of resection in patients with RPS. This review provides an overview of the current surgical principles for primary and recurrent RPS.

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

BACKGROUND AND OBJECTIVES

Surgical resection of retroperitoneal sarcomas (RPS) often involves removal of the ipsilateral kidney. We evaluated the long-term post-operative renal function in patients who underwent a nephrectomy as part of their en-bloc resection of RPS.

METHODS

Retrospective review of an institutional database identified RPS patients who underwent nephrectomy for curative intent from 1990 to 2014. The primary outcome measured was chronic kidney disease (CKD) calculated by the glomerular filtration rate (GFR).

RESULTS

Of the 47 patients in our study, 19 (40%), 18 (38%), and 10 (21%) patients had a preoperative CKD stage 1, 2, and 3, respectively. The GFR decreased by an average of 33.4 mL/min/1.73 m² with 66% of patients demonstrating mild progression of their renal impairment. Only three (6%) patients progressed to CKD stage 4 or 5, one of which required life-long dialysis.

CONCLUSION

Nephrectomy as part of an en-bloc resection is associated with a decrease in GFR that is not clinically significant. Fear of kidney failure should not prevent a surgeon from performing a nephrectomy in the treatment of RPS.