Retroperitoneal sarcoma: 25 years of experience with aggressive surgical treatment at the Institute of Oncology, Ljubljana

Rapid and Precise Diagnosis of Retroperitoneal Liposarcoma with Deep-Learned Label-Free Molecular Microscopy

The retroperitoneal liposarcoma (RLPS) is a rare malignancy whose only curative therapy is surgical resection. However, well-differentiated liposarcomas (WDLPSs), one of its most common types, can hardly be distinguished from normal fat during operation without an effective margin assessment method, jeopardizing the prognosis severely with a high recurrence risk. Here, we combined dual label-free nonlinear optical modalities, stimulated Raman scattering (SRS) microscopy and second harmonic generation (SHG) microscopy, to image two predominant tissue biomolecules, lipids and collagen fibers, in 35 RLPSs and 34 normal fat samples collected from 35 patients. The produced dual-modal tissue images were used for RLPS diagnosis based on deep learning. Dramatically decreasing lipids and increasing collagen fibers during tumor progression were reflected. A ResNeXt101-based model achieved 94.7% overall accuracy and 0.987 mean area under the ROC curve (AUC) in differentiating among normal fat, WDLPSs, and dedifferentiated liposarcomas (DDLPSs). In particular, WDLPSs were detected with 94.1% precision and 84.6% sensitivity superior to existing methods. The ablation experiment showed that such performance was attributed to both SRS and SHG microscopies, which increased the sensitivity of recognizing WDLPS by 16.0 and 3.6%, respectively. Furthermore, we utilized this model on RLPS margins to identify the tumor infiltration. Our method holds great potential for accurate intraoperative liposarcoma detection.

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.

Lifelong Imaging Surveillance is Indicated for Patients with Primary Retroperitoneal Liposarcoma

BACKGROUND

Surveillance imaging of patients with retroperitoneal liposarcoma (RP-LPS) after surgical resection is based on a projected risk of locoregional and distant recurrence. The duration of surveillance is not well defined because the natural history of RP-LPS after treatment is poorly understood. This study evaluated the long-term risk of recurrence and disease-specific survival (DSS) for a cohort of patients with at least 10 years of progression-free survival (10yr-PFS) from their primary resection.

METHODS

The prospective University of California, Los Angeles (UCLA) Sarcoma Database identified RP-LPS patients with 10yr-PFS after initial resection. The patients in the 10yr-PFS cohort were subsequently evaluated for recurrence and DSS. The time intervals start at date of initial surgical resection. Cox proportional hazards models were used to determine factors associated with recurrence and DSS.

RESULTS

From 1972 to 2010, 76 patients with RP-LPS had at least 10 years of follow-up evaluation. Of these 76 patients, 39 (51%) demonstrated 10yr-PFS. The median follow-up period was 15 years (range 10-33 years). Among the 10yr-PFS patients, 49% (19/39) experienced a recurrence at least 10 years after surgery. Of those who experienced recurrence, 42% (8/19) died of disease. Neither long-term recurrence nor DSS were significantly associated with age, sex, tumor size, LPS subtype, surgical margin, or perioperative treatment with radiation or chemotherapy.

CONCLUSION

Patients who have primary RP-LPS treated with surgical resection ± multimodality therapy face a long-term risk of recurrence and disease-specific death unacknowledged by current surveillance imaging guidelines. Among the patients with 10yr-PFS, 49% experienced a recurrence, and 42% of those died of disease. These findings suggest a need for lifelong surveillance imaging for patients with RP-LPS.

Analysis of potential risk factors in the survival of patients with primary retroperitoneal liposarcoma

INTRODUCTION

The present work is an observational study of a series of variables regarding overall survival and disease-free survival in patients diagnosed with primary liposarcoma.

METHODS

The study is prospective with retrolective data collection that includes all patients with primary liposarcoma referred to Hospital Son Espases University Hospital, Palma de Mallorca, Spain from January 1990 to December 2019.

RESULTS

The study includes 50 patients and the compartment surgery was performed in 18 patients (36%) of cases. The mean overall survival of the sample was 15.57 years (95% CI: 12.02-19.12) and the mean disease-free survival was 6.70 years (95% CI: 4.50-8.86).

CONCLUSION

Compartment surgery has not shown benefits in terms of overall survival and disease-free survival. The ASA classification (≥3) predicts a poor prognosis in both overall survival and disease-free survival. Resection with free margins, described on the pathological results and defined in this work as R0, show better disease-free survival.

Giant retroperitoneal low grade liposarcoma with left kidney displacement: A case report

Retroperitoneal liposarcomas are diagnostic and therapeutic challenge due to their expansive growth and tendency for recurrence. They represent the most of the sarcomas of the retroperitoneal space with the incidence of 41%. Most of them can grow in large proportions before symptom occurrence and change the anatomy of the retroperitoneum. Computerized tomography remains the main diagnostic tool in such cases that provides precise tumor location, size and relation to the adjacent organs. Surgery is the method of choice for treatment. Nevertheless, they tend to recur in 50%-80% of patients despite the appropriate surgery. We present a case of giant retroperitoneal liposarcoma in a female patient with significant left kidney displacement that recurred within 5 years of its removal.

Survival outcomes of surgery for retroperitoneal sarcomas: A systematic review and meta-analysis

Background

Definitive evidence to guide clinical practice on the principles of surgery for retroperitoneal sarcomas (RPSs) is still lacking. This study aims to summarise the available evidence to assess the relative benefits and disadvantages of an aggressive surgical approach with contiguous organ resection in patients with RPS, the association between surgical resection margins and survival outcomes, and the role of surgery in recurrent RPS.

Methods

We searched PubMed, the Cochrane Library, and EMBASE for relevant randomised trials and observational studies published from inception up to May 1, 2021. Prospective or retrospective studies, published in the English language, providing outcome data with surgical treatment in patients with RPS were selected. The primary outcome was overall survival (OS).

Findings

In total, 47 articles were analysed. There were no significant differences in the rates of OS (HR: 0.93; 95% CI: 0.83–1.03; P = 0.574) and recurrence-free survival (HR: 1.00; 95% CI: 0.74–1.27; P = 0.945) between the extended resection group and the tumour resection alone group. Organ resection did not increase postoperative mortality (OR: 1.00; 95% CI: 0.55–1.81; P = 0.997) but had a relatively higher complication rate (OR: 2.24, 95% CI: 0.94–5.34; P = 0.068). OS was higher in R0 than in R1 resection (HR: 1.34; 95% CI: 1.23–1.44; P < 0.001) and in R1 resection than in R2 resection (HR: 1.86; 95% CI: 1.35–2.36; P < 0.001). OS was also higher in R2 resection than in no surgery (HR: 1.26; 95% CI: 1.07–1.45; P < 0.001), however, subgroup analysis showed that the pooled HR in the trials reporting primary RPS was similar between the two groups (HR, 1.14; 95% CI, 0.87–1.42; P = 0.42). Surgical treatment achieves a significantly higher OS rate than does conservative treatment (HR: 2.42; 95% CI: 1.21–3.64; P < 0.001) for recurrent RPS.

Conclusions

For primary RPS, curative-intent en bloc resection should be aimed, and adjacent organs with evidence of direct invasion must be resected to avoid R2 resection. For recurrent RPS, surgical resection should be considered as a priority. Incomplete resection remains to have a survival benefit in select patients with unresectable recurrent RPS.

Primary retroperitoneal liposarcoma: a rare case report

Primary retroperitoneal liposarcoma (PRPLS) is a rare malignant tumor with a low incidence. A 34-year-old female patient presented to our department with abdominal pain, nausea, and vomiting for 2 days. Abdominal computed tomography (CT) indicated a huge mass between the liver and kidney, with a clear boundary and measuring approximately 202 mm × 155 mm ×106 mm. The mass was considered a retroperitoneal lipoma or liposarcoma. The entire tumor was completely resected without auxiliary injury, and histopathology of the resected specimen indicated liposarcoma. The patient recovered well and was discharged from our department on the 6th postoperative day. No signs of relapse were seen during 1-year of follow-up. PRPLS is rare and without obvious symptoms in the early stage. CT plays a vital role in the diagnosis of PRPLS, and surgical resection is considered the most suitable treatment. Radiotherapy and chemotherapy might also be treatment options to improve the overall survival of PRPLS patients.

Analysis of potential risk factors in the survival of patients with primary retroperitoneal liposarcoma

INTRODUCTION

The present work is an observational study of a series of variables regarding overall survival and disease-free survival in patients diagnosed with primary liposarcoma.

METHODS

The study is prospective with retrolective data collection that includes all patients with primary liposarcoma referred to Hospital Son Espases University Hospital, Palma de Mallorca, Spain from January 1990 to December 2019.

RESULTS

The study includes 50 patients and the compartment surgery was performed in 18 patients (36%) of cases. The mean overall survival of the sample was 15.57 years (95% CI: 12.02-19.12) and the mean disease-free survival was 6.70 years (95% CI: 4.50-8.86).

CONCLUSION

Compartment surgery has not shown benefits in terms of overall survival and disease-free survival. The ASA classification (≥3) predicts a poor prognosis in both overall survival and disease-free survival. Resection with free margins, described on the pathological results and defined in this work as R0, show better disease-free survival.

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.

Outcome after surgical resection of multiple recurrent retroperitoneal soft tissue sarcoma

INTRODUCTION

Local recurrences (LR) and distant metastases (DM) are common in retroperitoneal soft tissue sarcoma (RPS). Longer time to recurrence and resection of the recurrent lesion have been identified as beneficial prognostic factors for overall survival (OS) upon first tumor relapse. However, prognostic factors concerning OS upon subsequent recurrences are scarcely defined. In this study, we aimed to identify prognostic factors for post-relapse outcome in multiple recurrent RPS.

METHODS

Patients undergoing resection of primary and recurrent RPS at the University Hospital Heidelberg were retrospectively analyzed. Multivariable Cox regression analyses were performed to identify predictors of overall, LR- and DM-free survival. Subgroup analyses were performed for liposarcoma and leiomyosarcoma patients.

RESULTS

201 patients with primary disease, 101 patients with first, 66 patients with second and 43 patients with third LR as well as 75 patients with DM were analyzed. More than 12 months to recurrence and resection of recurrence were associated with improved OS after resection of first and second LR (5-year OS for first/second LR; resection: 64%/62%, no resection: 20%/46%). Gross macroscopic incomplete resection of first (p < 0.001), second (p = 0.001), and third recurrences (p < 0.001) was an independent prognostic factor for poor OS.

CONCLUSION

Development of LR and DM is frequent in RPS. Once a tumor relapsed, patients benefit from tumor resection not only in case of first, but also in case of subsequent recurrences.

Postoperative Morbidity After Resection of Recurrent Retroperitoneal Sarcoma: A Report from the Transatlantic Australasian RPS Working Group (TARPSWG)

BACKGROUND

This study aimed to evaluate perioperative morbidity after surgery for first locally recurrent (LR1) retroperitoneal sarcoma (RPS). Data concerning the safety of resecting recurrent RPS are lacking.

METHODS

Data were collected on all patients undergoing resection of RPS-LR1 at 22 Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG) centers from 2002 to 2011. Uni- and multivariable logistic models were fitted to study the association between major (Clavien-Dindo grade ≥ 3) complications and patient/surgery characteristics as well as outcome. The resected organ score, a method of standardizing the number of organs resected, as previously described by the TARPSWG, was used.

RESULTS

The 681 patients in this study had a median age of 59 years, and 51.8% were female. The most common histologic subtype was de-differentiated liposarcoma (43%), the median resected organ score was 1, and 83.3% of the patients achieved an R0 or R1 resection. Major complications occurred for 16% of the patients, and the 90-day mortality rate was 0.4%. In the multivariable analysis, a transfusion requirement was found to be a significant predictor of major complications (p < 0.001) and worse overall survival (OS) (p = 0.010). However, having a major complication was not associated with a worse OS or a higher incidence of local recurrence or distant metastasis.

CONCLUSIONS

A surgical approach to recurrent RPS is relatively safe and comparable with primary RPS in terms of complications and postoperative mortality when performed at specialized sarcoma centers. Because alternative effective therapies still are lacking, when indicated, resection of a recurrent RPS is a reasonable option. Every effort should be made to minimize the need for blood transfusions.

Primary localized retroperitoneal sarcomas: report from Slovenian sarcoma referral center

BACKGROUND

Sarcoma patients should be treated in high volume referral sarcoma centers. Compartmental resection is proposed as the best treatment option in retroperitoneal sarcoma patients.

METHODS

Institute of Oncology Ljubljana is the only referral sarcoma center in Slovenia. Having a population of 2.1 million poses a unique situation. We manage all sarcoma patients in the country and operate on patients with soft tissue tumors of extremities, trunk, and abdomen. Data for all consecutive patients surgically treated from January 1999 to December 2018 for primary localized retroperitoneal sarcoma was extracted from a prospective surgical database. Data about the incidence of sarcoma patients in Slovenia was extracted from the Cancer Registry of Republic of Slovenia. Clinicopathologic variables and the outcome were analyzed.

RESULTS

In total, 89 patients were included in the study. Median age was 62 years. Dedifferentiated liposarcoma was the most common histology (38.2%). Median tumor size was 21 cm. Compartmental resection was performed in 47.2% (42/89). Postoperative complication grade 3a or higher according to Clavien-Dindo classification had 30.3% (27/89) of patients. The 30-day and 90-day mortality rate was 2.2% and 5.6%. Median follow-up was 62.1 months. Corresponding 5-year overall survival was 67.2%, 5-year disease-specific survival was 72.6%, and 5-year local recurrence-free survival was 81.5%, respectively.

CONCLUSION

Results from our institution show that referral sarcoma centers may achieve very good results in management of retroperitoneal sarcoma patients, despite not meeting the criteria for high volume hospitals, as long as they have multidisciplinary team, appropriate facilities, and expertise.

Role of neoadjuvant Radio-Chemotherapy for retroperitoneal Liposarcoma in primary and secondary surgical intervention

Abstract Background: Approximately 30–40 % of all retroperitoneal soft tissue tumors are sarcomas with liposarcoma prevailing in approximately 50% of these cases. Retroperitoneal liposarcomas typically show a high rate of local recurrence and late distant metastases. The aim of our retrospective analysis was to investigate the efficacy of treatment in our patients with liposarcoma. Methods: Thirty-four consecutive patients underwent surgery in our clinic between October 2004 and November 2017. Liposarcomas arising from the mesenteric or abdominal adipose tissue or the pelvis were excluded. In 2011 we had introduced neo-adjuvant therapy according to IAWS-Guidelines in patients younger than seventy without severe comorbidities to pretreatement. Results: Out of 34 patients, 23 (67,6%) presented with primary and 11 (32,4%) with recurrent disease. In 8 of the 27 patients (30 %), a radical resection (R0) could be achieved, and in 17 patients (63%) resection was marginal (R1). Time to recurrence was not affected by neoadjuvant radiotherapy. Patients that underwent systemic chemotherapy followed by radiotherapy developed earlier recurrences (p = 0.016). Overall survival appeared to be better in the neoadjuvant group but was not significant (0.080) Conclusions: Combining surgical resection with neoadjuvant radiation treatment showed survival benefits in primary but not recurrent disease. Repeated surgery stays a valid approach in carefully selected patients but all patients should be referred to a center of expertise in multimodal treatment approaches for retroperitoneal liposarcomas.

[Multiple recurrent retroperitoneal liposarcoma in a 66-year-old man]

In this article, the authors present the case of a 66-year-old man who was diagnosed with the first recurrence of his retroperitoneal liposarcoma 7 years after initial diagnosis. In the following 10 years, he needed a total of eight operations, chemotherapy, and radiotherapy because of another seven recurrences. This is the first report on a patient with eight recurrences of a retroperitoneal liposarcoma being in a relatively good general condition even 17 years after initial diagnosis.

Cytoreductive Surgery for Metastatic Gastrointestinal Stromal Tumors Treated With Tyrosine Kinase Inhibitors: A 2-institutional Analysis

OBJECTIVE

To refine treatment recommendations for patients with metastatic gastrointestinal stromal tumors (GISTs) treated with tyrosine kinase inhibitors (TKIs) and surgery.

BACKGROUND

Early reports suggested that patients with metastatic GIST responding to TKIs treated with surgery may have favorable outcomes. However, identification of prognostic factors was limited by small cohorts.

METHODS

Progression-free survival (PFS) and overall survival (OS) from time of surgery and from start of initial TKI was determined. Multivariate analysis was conducted on all patients undergoing GIST metastasectomy between 2001 and 2014 at 2 institutions.

RESULTS

We performed 400 operations on 323 patients with metastatic GIST on TKIs. Radiographic response at time of surgery was classified as responsive disease (RD, n = 64, 16%), stable disease (SD, n = 100, 25%), unifocal progressive disease (UPD, n = 132, 33%), and multifocal progressive disease (MPD, n = 104, 26%). For patients on imatinib before surgery, radiographic response was predictive of PFS from time of surgery (RD 36 months, SD 30 months, UPD 11 months, MPD 6 months; P < 0.001) and from imatinib initiation (RD 71 months, SD 51 months, UPD 47 months, MPD 33 months; P < 0.001). Radiographic response was predictive of OS from time of surgery (RD not reached, SD 110 months, UPD 59 months, MPD 24 months; P < 0.001), and from imatinib initiation (RD not reached, SD 144 months, UPD 105 months, MPD 66 months; P = 0.005). Radiographic response was not predictive of PFS/OS for patients on sunitinib. Metastatic mitotic index ≥5/50 HPF, MPD, and R2 resection were prognostic of worse PFS/OS; primary mutation was not.

CONCLUSIONS

Surgery in metastatic GIST patients in the absence of MPD on imatinib is associated with outcomes at least comparable with second-line sunitinib and may be considered in select patients.

Vascular leiomyosarcoma originating from the right ovarian vein: a case report and literature review

Background

Primary leiomyosarcoma (LMS) of vascular origin is a rare lesion, and patients with LMS of vascular origin have poorer prognoses than patients with LMS of other origins. The inferior vena cava is the most commonly affected vessel and accounts for 60% of all vascular cases. However, LMS originating from the ovarian vein is extremely rare, and we are only aware of 15 reported cases. Therefore, we report our experience with a case of LMS originating from the right ovarian vein and review the related literature.

Case presentation

A 71-year-old Japanese woman with no symptoms was admitted to our hospital because of abnormal findings in a routine abdominal ultrasonography check-up. Contrast-enhanced computed tomography of the abdomen revealed a well-defined, lobulated solid mass with a diameter of 5.5 cm in the right retroperitoneal space. The mass exhibited relatively low uptake during ¹⁸F-fluorodeoxyglucose positron emission tomography. Based on these findings, the differential diagnosis included a retroperitoneal tumor, such as a desmoid tumor, leiomyoma, LMS, and malignant mesothelioma. Operative findings confirmed that the mass had originated from the right ovarian vessels, and en bloc excision was performed for the mass and the right ovarian vessels. The final pathological diagnosis was LMS originating from the right ovarian vein, and the surgical resection margins were free from tumor cells. After histological findings confirmed the LMS diagnosis, the patient underwent adjuvant radiation therapy and has not exhibited signs of local recurrence or metastasis in the 6 months after surgery.

Conclusions

We encountered a 71-year-old woman with LMS originating from her right ovarian vein. The prognosis of vascular LMS is generally poor. Therefore, careful follow-up will be required for our patient.

Optimal maximum duration for delaying salvage operation when recurrence of retroperitoneal liposarcoma is suspected: a single-center study

BACKGROUND

This study was designed to identify the optimal maximum duration for delaying salvage operation when recurrence of retroperitoneal liposarcoma (LPS) is suspected.

METHODS

Patients who underwent salvage operation at Samsung Medical Center for recurrent retroperitoneal LPS from January 2000 to December 2015 were reviewed. The time interval between recurrence and operation for recurrence was divided by 1, 2 or 3 months. A Cox proportional-hazards model was used to analyze factors related to disease-free survival along with recurrence-to-operation interval divided by 1, 2 or 3 months.

RESULTS

The 1-, 3-, and 5-year disease-free survival rates were 43.2%, 15.6% and 13.4%, respectively. FNCLCC grade (p = 0.023) and recurrence-to-operation interval divided by 3 months (p = 0.003) were significant factors associated with recurrence. FNCLCC grade 2 (HR 1.940, CI 0.935-4.026, p = 0.238) and grade 3 (HR 4.049, CI 1.767-9.281, p = 0.007) showed increased risk compared to grade 1. Patients who underwent salvage operation more than 3 months after recurrence showed significantly increased risk of recurrence compared to patients within 3 months (HR 2.724, CI 1.391-5.337, p = 0.003).

CONCLUSIONS

Based on our analysis of recurrence-free survival, salvage operation can be delayed for less than 3 months when recurrence is suspected. A short-term follow-up imaging study should be performed within this period.

Recurrent Retroperitoneal Liposarcoma: a Case Report and Literature Review

This is a case report of a 61-year-old male patient, presented with fifth recurrence of retroperitoneal liposarcoma and operated for six times. Literature review on retroperitoneal liposarcoma biology, recurrence pattern, role of surgery in primary tumor, and recurrent tumor, adjuvant therapy, role of multivisceral resection, and palliative surgery.

Radical Nephrectomy for Primary Retroperitoneal Liposarcoma Near the Kidney has a Beneficial Effect on Disease-Free Survival

BACKGROUND

The purpose of this study is to analyze the clinical impact of radical nephrectomy on retroperitoneal liposarcoma near the kidney.

METHODS

Data of patients who underwent surgery for unilateral primary retroperitoneal liposarcoma near the kidney were retrospectively collected. Patients were divided into four groups according to whether they underwent nephrectomy and combined resection of other organs. Kaplan-Meier survival analysis was used to estimate disease-free survival and overall survival. Multivariable Cox analysis was used to analyze factors related to disease-free survival and overall survival.

RESULTS

Nephrectomy (HR = 0.260, CI = 0.078-0.873, p = 0.029) had a beneficial effect on disease-free survival, while interaction model of nephrectomy*other organ resection (HR = 4.655, CI = 1.767-12.263, p = 0.002) showed poor disease-free survival. Other organ resection was not related to disease-free survival (HR = 1.543, CI = 0.146-16.251, p = 0.718). Operation method (p = 0.007) and FNCLCC grade (p < 0.001; G2, HR = 1.833, CI = 0.684-4.915, p = 0.228; G3, HR = 9.190, CI = 3.351-25.199, p < 0.001) were significant factors for disease-free survival. While combined organ resection without nephrectomy group (HR = 1.604, CI = 0.167-15.370, p = 0.682) and radical nephrectomy with combined organ resection group (HR = 1.309, CI = 0.448-3.825, p = 0.622) did not show significant difference in disease-free survival from the mass excision only group, radical nephrectomy without combined organ resection group (HR = 0.279, CI = 0.078-0.991, p = 0.048) showed superior disease-free survival.

CONCLUSIONS

Radical nephrectomy of unilateral primary retroperitoneal liposarcoma near the kidney has a beneficial effect on disease-free survival.

Aggressive Surgical Approach for Treatment of Primary and Recurrent Retroperitoneal Soft Tissue Sarcoma

To analyze treatment and survival in a series of resected patients with primary or recurrent retroperitoneal sarcoma (RPS) treated and prospectively followed at a single institution. Between July 1994 and December 2015, 89 patients (36 M, 53 F; mean age 60 years, range 25-79) were evaluated. For the purpose of analysis, complete resection was defined as removal of gross tumor with histologically confirmed clear resection margins. Eighty-three out of the 89 patients (93%), 46 of whom affected by primary RPS, and 37 by recurrent RPS, underwent surgical exploration. Sixty-two had a grossly and microscopically complete resection. Fifty-three out of 83 patients (64%) underwent removal of contiguous intra-abdominal organs. Preoperative mortality was nil and significant preoperative complications occurred in six cases only (7%). High-grade tumor pointed out to be a significant variable for a worse survival in all 83 patients amenable to undergo surgical resection (57% 5 years survival for low grade vs 14% for high grade; P = 0.0004). Among completely resected patients, only histologic grade clearly affected disease-free survival (72% 5 years survival for low grade vs 50% for high grade; P = 0.04), while the role of preoperative blood transfusions (67% 5 years survival for non-transfused patients vs 29% for transfused patients; P = 0.05) has to be evaluated in connection to patient complexity. Histological grade and recurrence are the most valuable prognostic predictors; in this clinical subset, an aggressive surgical approach in both primary and recurrent RPS is associated with a best long-term survival and disease-free survival.

Dyspnea caused by a giant retroperitoneal liposarcoma: A case report

Liposarcomas are the most common soft tissue tumors with various histological subtypes. They usually appear in the retroperitoneal region of the abdomen, but their symptomatology remains unclear and their diagnosis, as well as treatment challenging. A case of a 55-year-old female patient with dyspnea and light diffuse abdominal pain caused by a giant retroperitoneal liposarcoma is presented. The patient had an unremarkable medical history, while the computed tomography scan revealed a large mass at the right portion of the abdomen, with its upper limits to the lower edge and the gate portion of the liver. The mass was in contact with the right kidney, the inferior vena cava and the right renal vein, causing mild dilation of the right kidney pelvis. Without any evidence of intra-abdominal metastases, the tumor was surgically resected. The histological analysis of the tumor revealed a well-differentiated liposarcoma. The patient had an uneventful recovery and was discharged on the 10th postoperative day. Until today (4 years later) she remains asymptomatic, without any signs of recurrence. The retroperitoneal liposarcoma is a clinical entity with unclear clinical symptoms and the physician should consider including it in the differential diagnosis of a majority of symptoms, such as dyspnea.

Retroperitoneal Soft Tissue Sarcoma: Prognostic Factors and Therapeutic Approaches

Aims and Background

Retroperitoneal sarcomas are a rare group of malignant soft tissue tumors with a generally poor prognosis. The aim of the study was to assess clinical, pathological and treatment-related factors affecting prognosis in patients with retroperitoneal sarcomas.

Methods and Study Design

The hospital records of 73 patients who underwent surgical exploration at our unit for primary retroperitoneal sarcomas between 1984 and 2003 were reviewed. Factors influencing overall and disease-free survival were analyzed for all patients and for those who underwent complete surgical resection.

Results

The complete resectability rate was 69.8% (51/73). Operative mortality and morbidity rates were 2.7% and 21.9%, respectively. For patients who underwent complete resection, the 5-year survival rate was 58.3%, whereas it was 0% in cases of incomplete or no resection (P <0.001). Local recurrence rate was 37.2%. Incomplete gross surgical resection and microscopic infiltration of margins were the most important independent predictors of a poor prognosis.

Conclusions

The present study confirmed the importance of an aggressive surgical management for retroperitoneal sarcomas to offer these patients the best chance for long-term survival.

Volumetric-modulated arc therapy versus intensity-modulated radiotherapy for large volume retroperitoneal sarcomas: A comparative analysis of dosimetric and treatment delivery parameters

Purpose

To compare dosimetric and treatment delivery parameter differences between volumetric‐modulated arc radiotherapy (VMAT) and intensity‐modulated radiotherapy (IMRT) for large volume retroperitoneal sarcomas (RPS).

Materials and Methods

Both VMAT and IMRT planning were performed on CT datasets of 10 patients with RPS who had been previously treated with preoperative radiotherapy. Plans were optimized to deliver ≥95% dose to the PTV and were evaluated for conformity and homogeneity. Dose to the organs at risk (OARs) (kidney, liver, spinal cord, and bowel space), unspecified tissue, and dose evaluation volumes (DEVs) at 1, 2, and 5 cm from PTV were calculated and compared. Monitor units (MUs) and treatment delivery times were recorded and compared between the two techniques. The deliverability of the large volume RPS VMAT plans was verified by portal dosimetry on a Truebeam™ linac.

Results

VMAT and IMRT plans were equivalent for PTV coverage and homogeneity (P > 0.05); however, VMAT plans had slightly better conformity index, CI (P < 0.001). Doses to the OARs were not significantly different between VMAT and IMRT plans (P > 0.05). Mean doses to the unspecified tissue as well as at 1, 2, and 5 cm DEVs were lower with VMAT compared with IMRT, P = 0.04 and P < 0.01, respectively. MUs and average beam‐on times were both significantly lower in the VMAT vs IMRT plans, P < 0.001 and P = 0.001, respectively. All VMAT plans passed portal dosimetry delivery verification with an average gamma passing rate of 99.6 ± 0.4%.

Conclusions

VMAT planning for large volume RPS improved CI, and achieved comparable OAR sparing, as compared with IMRT. As treatment delivery time was lower, the use of VMAT for RPS may translate into improved treatment delivery efficiency.

Retromammary fat, axillary and arm metastases from a retroperitoneal leiomyosarcoma: report of a case with an indolent behaviour

Leiomyosarcomas are sarcomas that originate within smooth muscle cells and generally occur in older patients. These tumours account for 10% of all soft-tissue sarcomas. Metastases occur most commonly to the lungs, kidneys, and liver. Cutaneous metastases may also occur but are usually a very rare and late event. We present a case of a 46-year-old woman who developed subcutaneous metastasis to the axilla, arm and breast after surgical resection of the primary tumour.

The patient maintained controlled disease with surgical resections and clinical follow-up, initiating chemotherapy one year after the diagnosis of metastatic disease.

Leiomyosarcoma of the renal vein: analysis of outcome and prognostic factors in the world case series of 67 patients

BACKGROUND

Leiomyosarcoma is a rare malignant mesenchymal tumour. Some cases of leiomyosarcoma of the renal vein (LRV) have been reported in the literature, but no analysis of data and search for prognostic factors have been done so far. The aim of this review was to describe the LRV, to analyse overall survival (OS), local recurrence free survival (LRFS) and distant metastases free survival (DMFS) in LRV world case series and to identify significant predictors of OS, LRFS and DMFS.

METHODS

Cases from the literature based on PubMed search and a case from our institution were included.

RESULTS

Sixty-seven patients with a mean age of 56.6 years were identified; 76.1% were women. Mean tumour size was 8.9 cm; in 68.7% located on the left side. Tumour thrombus extended into the inferior vena cava lumen in 13.4%. All patients but one underwent surgery (98.5%). After a median follow up of 24 months, the OS was 79.5%. LRFS was 83.5% after a median follow up of 21.5 months and DMFS was 76.1% after a median follow up of 22 months. Factors predictive of OS in univariate analysis were surgical margins, while factors predictive of LRFS were inferior vena cava luminal extension and grade. No factors predictive of DMFS were identified. In multivariate analysis none of the factors were predictive of OS, LRFS and DMFS.

CONCLUSIONS

Based on the literature review and presented case some conclusions can be made. LRV is usually located in the hilum of the kidney. It should be considered in differential diagnosis of renal and retroperitoneal masses, particularly in women over the age 40, on the left side and in the absence of haematuria. Core needle biopsy should be performed. Patients should be managed by sarcoma multidisciplinary team. LRV should be surgically removed, with negative margins.

Retroperitoneal Sarcomas

Retroperitoneal sarcomas are rare tumors, representing only 15% of all sarcomas. The mainstay of therapy is surgical resection with negative margins. However, this is challenging because of the late presentation of many of these tumors and involvement with adjacent structures. Decisions on radiation therapy and chemotherapy should be made in a multidisciplinary setting at a tertiary referral center.

Tissue expander placement and adjuvant radiotherapy after surgical resection of retroperitoneal liposarcoma offers improved local control

Given that retroperitoneal liposarcoma (LPS) is extremely difficult to completely resect, and has a relatively high rate of recurrence, radiotherapy (RT) is the treatment of choice after surgical resection. However, it is difficult to obtain a sufficient radiation field because of the close proximity of surrounding organs. We introduce the use of tissue expanders (TEs) after LPS resection in an attempt to secure a sufficient radiation field and to improve recurrence-free survival.This study is a retrospective review of 53 patients who underwent surgical resection of LPS at Samsung Medical Center between January 1, 2005, and December 31, 2012, and had no residual tumor detected 2 months postoperatively. The median follow-up period was 38.9 months.Patients were divided into 3 groups. Those in group 1 (n = 17) had TE inserted and received postoperative RT. The patients in group 2 (n = 9) did not have TE inserted and received postoperative RT. Finally, those in group 3 (n = 27) did not receive postoperative RT. Multivariate analysis was performed to identify the risk factors associated with recurrence-free survival within 3 years. Younger age, history of LPS treatment, and RT after TE insertion (group 1 vs group 2 or 3) were significantly favorable factors influencing 3-year recurrence-free survival.TE insertion after LPS resection is associated with increased 3-year recurrence-free survival, most likely because it allows effective delivery of postoperative RT.

Subcutaneous Axillary and Scalp Metastases from Non-Gynecological Retroperitoneal Leiomyosarcoma: An Unusual Presentation After Surgical Resection

Retroperitoneal leiomyosarcomas are rare sarcomas, with an incidence of less than 2 per million population. Cutaneous metastases from sarcoma account for only 1-2.6% of metastatic skin lesions. Cutaneous and subcutaneous metastasis from retroperitoneal leiomyosarcoma is a very rare entity. We present a case of 72-year-old male with scalp nodule and subcutaneous swelling in left posterior axillary fold. Fine needle aspiration cytology from both these sites revealed a sarcoma, which was positive for Smooth Muscle Actin and negative for S100 on cell block immuno-histochemistry (IHC). The past history revealed surgical resection of a retroperitoneal mass in 2010 which was diagnosed on histopathology and IHC as leiomyosarcoma. A final diagnosis of metastatic deposits from leiomyosarcoma was made. Retroperitoneal leiomyosarcoma presenting as scalp and subcutaneous metastasis is an unusual presentation. Adequate clinical history and a high index of clinical suspicion is required to detect cutaneous and subcutaneous metastatic deposits occurring five years after surgical resection.

Uterine Lipoleiomyoma in Peri or Postmenopausal Women

Lipoleiomyoma is an uncommon neoplasm of the uterus, composed of smooth muscles intermixed with mature adipocytes. These tumors are considered a benign variant of uterine leiomyomas. Herein, we report six cases of lipoleiomyoma experienced in our institution from January 2005 to March 2015. The patients ranged in age from 45 to 70 years; the etiology may be related to estrogen deficiency occurring after menopausal transition. Except for one lipoleiomyoma in the broad ligament, all others were found in the uterine corpus. The presenting symptoms were nonspecific, and most cases were incidentally diagnosed during surgery for other reasons. We performed preoperative imaging studies, including abdominal and pelvic computed tomography and magnetic resonance imaging. Preoperatively, four patients were diagnosed as having a pelvic mass and one patient was diagnosed as having a right ovarian mature teratoma. In one case, we found a gynecologic malignancy (cervical cancer 1A1). Histologically, there was no gross or microscopic contiguity between the lipoleiomyoma and the malignancy. Lipoleiomyomas seem to have a benign clinical course. In our study, there were no recurrences of or deaths attributed to the lipoleiomyomas during a mean follow-up period of 16.17 ± 23.80 months.

Prognostic factors predicting the postoperative survival period following treatment for primary retroperitoneal liposarcoma

Background:

Liposarcomas, which represent 20% of all adult sarcomas, are the most common histological type of malignant soft tissue tumors. The aim of this study was to define the prognostic factors that predict the postoperative survival period for patients with primary retroperitoneal liposarcoma.

Methods:

The clinical data and prognoses of 71 patients with primary retroperitoneal liposarcoma who were treated in the General Hospital of the People's Liberation Army of China between January 1, 2000 and December 31, 2007 were retrospectively reviewed and analyzed.

Results:

The primary tumor from each patient was resected; 54.9% (39/71) were deemed R0 resections, 31.0% (22/71) were R1 resections and 14.1% (10/71) were deemed R2 resections (palliative operations). The median follow up was 68 months (range: 1-160 months). Of the patients who received an R1 or R2 resection of their primary tumor, 96.7% (59/61) had tumor recurrence. The 1-year, 3-year, and 5-year recurrence-free rates were 77.0%, 29.8% and 19.7%, respectively. As of April 2013, 53 of the 71 patients had died from tumor recurrence. The overall 1-year, 3-year, 5-year, and 10-year survival rates were 88.7%, 76.1%, 61.7%, and 30.4%, respectively. The factors that were significantly associated with prognosis in the univariate analysis were age (as a categorical variable) (P = 0.006), modus operandi (P = 0.000), histologic subtype (P = 0.000), tumor grade (P = 0.000), ascites (P = 0.000), postoperative metastasis (P = 0.000) and adjuvant therapy (P = 0.030). However, in the multivariate analysis, the modus operandi (P = 0.000), tumor grade (P = 0.006), ascites (P = 0.027), postoperative metastasis (P = 0.023) and age (as a categorical variable) (P = 0.002) were the only significant predictors of survival.

Conclusions:

Complete resection remains the most effective method for treating liposarcoma. High grade, old age (≥60 years old), postoperative metastasis, and ascites predict poor prognoses.

Retroperitoneal liposarcoma: a comprehensive review

Retroperitoneal liposarcomas are rare mesenchymal tumors of the retroperitoneum that typically present with advanced disease and often carry a poor prognosis. Because of their rarity and anatomic location, these malignant tumors can cause a diagnostic dilemma and present several therapeutic challenges. They are usually associated with a high rate of recurrence despite grossly complete resection, thus requiring long-term and often indefinite follow-up. Relevant data on this topic was procured and synthesized with the aid of a comprehensive Medline search in addition to oncologic, pathologic, urologic, radiologic, and surgical literature review on retroperitoneal sarcomas. This article provides an in-depth review into the natural history, pathology, clinical manifestations, and prognostic features of retroperitoneal liposarcomas. It also discusses the reliability of diagnostic procedures and novel curative approaches that are currently being evaluated for the disease.

Well-differentiated abdominal liposarcoma: experience of a tertiary care center

Background

We presented abdominal liposarcoma cases diagnosed and managed in a tertiary care center and also conducted a literature review on main features of this tumor.

Methods

Chart reviews of eight cases were conducted, and clinical, surgical, histopathological, and follow-up data were recorded.

Results

Overall, complete surgical resection was performed with adjacent organ resection in 25% of cases, and radiotherapy was not administered. Recurrence was developed in only one case and died after 2 years and 3 months, and other cases are under follow-up without recurrence. Histopatological examinations revealed findings of well-differentiated liposarcoma.

Conclusions

According to our surgical experience, the surgical margin positivity may not be a determining factor for the survival of patients with well-differentiated liposarcoma, and in the absence of macroscopic invasion, adjacent organ resection may not be required. Radiotherapy may not be preferred when complete resection of abdominal mass was achieved.

Retroperitoneal leiomyoma of the uterus mimicking sarcoma in perimenopausal woman: case report

Leiomyomas are very common benign tumors in the uterus and it is rare condition to present the retroperitoneal leiomyoma. The author reported a 48-year-old female patient who presented right pelvic mass with urinary incontinence and lower abdominal discomfort. Based on the preoperative imaging, provisional diagnosis was mesenchymal sarcoma. In the intraoperative findings, huge mass abutting to the uterus was observed in retroperitoneal space beneath the right broad ligament. After the exposure the retroperitoneal space, we encountered the well-demarcated tumor measuring 8 × 6 cm in diameter and this tumor attached the right surface of the uterus with fibrotic tissue. Pathologic findings demonstrated retroperitoneal uterine leiomyoma.

Safety and efficacy of radiation dose delivered via iodine-125 brachytherapy mesh implantation for deep cavity sarcomas

BACKGROUND

Radiation delivered as brachytherapy (BRT) via catheters placed during extremity soft tissue sarcoma (STS) resection results in acceptable local control rates; however, there are limitations in deep cavities. (125)I seeds embedded in mesh provide a flexible BRT platform that may be contoured to irregular deep cavities surfaces, but the risks and benefits are unknown.

METHODS

Patients with thoracic, abdominal, pelvic, retroperitoneal, and deep truncal STS undergoing resection and implantation of permanent (125)I mesh BRT at our institution were reviewed. Local recurrence rates within the tumor bed covered by mesh (in field) and postoperative complications were analyzed.

RESULTS

Between 2000 and 2010, a total of 46 patients were treated for primary (n = 8, 17 %) or recurrent (n = 38, 83 %) deep cavity STS (median follow-up 34.8 months); 74 % received external-beam radiotherapy for this or a prior presentation. In-field recurrences were observed in 9 patients (19.5 %). Crude cumulative incidences of in-field, regional, and distant recurrences at 5 years were 26.3, 54.2, and 54.1 %, respectively. 5-year overall survival rate was 47.2 %; median survival was 44.0 months. Twenty-two patients (48 %) experienced complications, half of whom (24 %) developed grade III/IV complications requiring percutaneous intervention (n = 6) or reoperation (n = 5) at a median of 35.5 days. There were no postoperative deaths.

CONCLUSIONS

To our knowledge, this is the first study to report safety and efficacy for permanent (125)I mesh BRT implantation after resection of deep cavity STS. Local in-field recurrence rates were relatively low in this high-risk population. However, 24 % developed complications requiring intervention. (125)I mesh BRT appears effective, but it should be used with caution.

[Surgery and postoperative radiation therapy in primary retroperitoneal sarcomas: experience of the cancer centre Alexis-Vautrin]

PURPOSE

Surgical resection remains the standard treatment for patients with resectable retroperitoneal sarcomas. The aim of this study was to retrospectively analyse the outcomes of patients with primary retroperitoneal sarcoma.

PATIENTS AND METHODS

We analysed data of 50 patients with primary retroperitoneal sarcoma who underwent curative-intent resection from 1975 to 2008. External beam radiotherapy and chemotherapy were delivered postoperatively. Demographics, surgical, pathological variables and chemo/radiation therapy were analysed as prognosis factors.

RESULTS

There were 22 males and 28 females (mean age 54 ± 13 years). Surgery required visceral resections in 30 patients. There were 16 leiomyosarcomas, 25 liposarcomas and eight other sub-types. Twenty-one patients had clear surgical margins. Twenty-eight patients received postoperative external beam radiotherapy (median 45 Gy) and 15 received chemotherapy. At the end of the follow-up (median 55 months), local recurrence occurred in 39% (n=14) among R0/R1 resection group (n=36). Postoperative external beam radiotherapy tends to increase the time of local recurrence from surgery (27 vs. 13 months, P=0.05). The overall survival rates were 81%, 55% and 46% at 1, 3 and 5 years, respectively. Although R0 resection (P=0.01), well tumour differentiation (P=0.004) and postoperative external beam radiotherapy (P=0.02) significantly influenced overall survival in univariate analysis, only R0 resection was an independent prognostic factor in a multivariate analysis.

CONCLUSION

We confirm the pre-eminence of radical surgery with negative margins as major prognostic factor and the benefit of postoperative radiotherapy.

Complete and safe resection of challenging retroperitoneal tumors: anticipation of multi-organ and major vascular resection and use of adjunct procedures

BACKGROUND

Retroperitoneal tumors are often massive and can involve adjacent organs and/or vital structures, making them difficult to resect. Completeness of resection is within the surgeon's control and critical for long-term survival, particularly for malignant disease. Few studies directly address strategies for complete and safe resection of challenging retroperitoneal tumors.

METHODS

Fifty-six patients representing 63 cases of primary or recurrent retroperitoneal tumor resection between 2004-2009 were identified and a retrospective chart review was performed. Rates of complete resection, use of adjunct procedures, and perioperative complications were recorded.

RESULTS

In 95% of cases, complete resection was achieved. Fifty-eight percent of these cases required en bloc multi-organ resection, and 8% required major vascular resection. Complete resection rates were higher for primary versus recurrent disease. Adjunct procedures (ureteral stents, femoral nerve monitoring, posterior laminotomy, etc.) were used in 54% of cases. Major postoperative complications occurred in 16% of cases, and one patient died (2% mortality).

CONCLUSIONS

Complete resection of challenging retroperitoneal tumors is feasible and can be done safely with important pre- and intraoperative considerations in mind.

Radiotherapy and surgery-an indispensable duo in the treatment of retroperitoneal sarcoma

The authors undertook a systematic review to designate the role that radiotherapy (RT) might play in the treatment of retroperitoneal sarcomas. Correlating with recent literature, the objective of this review was to evaluate whether there was enough evidence for the authors to develop an institutional treatment protocol concerning the use of RT in the treatment of retroperitoneal sarcoma. Furthermore, this was a call for surgeons to talk to radiation oncologists before performing surgery. The 2 objectives of this review were: 1) to determine the benefit of RT in terms of local control and/or survival in the treatment of retroperitoneal sarcomas and 2) to discover the optimal timing of RT in the treatment sequence. A computerized literature search was performed in the PubMed database, the Cochrane Library database, and reference lists; and journals also were searched by hand to identify all retrospective and prospective reports published since 1998 relating to RT treatment of adult retroperitoneal sarcoma. Mainly, analyses were sought that were based on a 5-year local control rate (LCR), 5-year disease-free survival, and 5-year overall survival (OS). If only 2 years follow-up were available, then the authors also noted this outcome. Toxicity data were collected and analyzed separately. The synthesis of the literature was based on 9 prospectively nonrandomized studies and 10 retrospective studies that, together, reviewed a total of 1426 patients. The 5-year LCR varied from 27% to 62%, and the results from other reports fell in between those values. The 5-year OS rate ranged from 12% to 90%, and complete resection and tumor grade were the most important prognostic factors in most studies. This review resulted in 7 recommendations concerning the use of RT in the treatment of retroperitoneal sarcoma. The authors concluded that there is good evidence from multiple single-institutions studies that RT improves the LCR in patients with retroperitoneal sarcoma. Until now, there has not been a translation of this approach into survival benefit. The current results indicated that preoperative external-beam RT followed by radical surgery seems to be the preferred sequence, and adding intraoperative RT is a safe procedure for dose escalation in the upper abdomen.

Intraabdominal and retroperitoneal soft-tissue sarcomas--outcome of surgical treatment in primary and recurrent tumors

BACKGROUND

Surgery is the only curative treatment for intraabdominal and retroperitoneal sarcoma (IaRS). Little is known about how to treat patients with recurrence. We here report the outcome in primary and recurrent sarcoma treated at the Sarcoma Center in Aarhus, Denmark.

METHODS

All patients evaluated for IaRS from June 1998 to May 2008 were enrolled and data on symptoms, signs, means of diagnosis, extent of surgery, perioperative complications, mortality and long time survival were registered. Primary and first-recurrence sarcomas were analyzed separately.

RESULTS

Sixty-five of 73 primary and 22 of 28 first-recurrence IaRS had surgery. Fifty-three (82%) and 11 (50%) patients achieved radical R0 resection. Age and radicality of surgery were independent predictors of death, while recurrence of sarcoma was not. Perioperative mortality was 2.3%. 5-year survival was 70.2% for primary and 51.8% for first-recurrent sarcomas. However, patients with radical surgery had 5-year survival of over 70% in both the primary and recurrent group.

CONCLUSIONS

The radicality of surgery is the most important prognostic factor. Patients with recurrence have an equally good prognosis as those with primary sarcoma if radicality is achieved and such surgery should not be considered only as a palliative effort.

Radiotherapy and extent of surgical resection in retroperitoneal soft-tissue sarcoma: multi-institutional analysis of 261 patients

BACKGROUND AND OBJECTIVE

To examine the impact of adjuvant radiotherapy (RT) and surgical technique on survival in retroperitoneal soft-tissue sarcoma.

METHODS

A retrospective analysis was conducted using the National Oncology Database, a proprietary database of aggregated tumor registries owned by IMPAC(R) Medical Systems (Sunnyvale, CA). Patients who received definitive surgery with negative or microscopic-positive margins were included. Multivariate analysis was performed using the Cox proportional hazards model. Survival curves were estimated by the Kaplan-Meier method and were compared for statistical significance (P < 0.05) using the log-rank test.

RESULTS

Two hundred sixty-one patients met inclusion criteria. The median follow-up was 59 months (range 0.2-186 months). The 5-year cause-specific survival (CSS) and local failure-free survival (LFFS) were 73% and 66%, respectively. Grade, margin status, and histology were independent predictors for CSS (P < 0.05). Adjuvant RT was associated with a significant improvement in LFFS over surgery alone (hazard ratio = 0.42, 95% confidence interval 0.21-0.86, P < 0.05). Patients receiving simple excision and RT had a 5-year LFFS of 88%, significantly higher than wide resection with or without RT (log-rank, P < 0.05).

CONCLUSION

Adjuvant RT is associated with a lower risk of local relapse compared to surgery alone. The impact of surgical technique on adjuvant RT efficacy warrants further study.

Current concepts in the management of retroperitoneal soft tissue sarcoma

Soft tissue sarcomas (STS) in the retroperitoneum are usually diagnosed at the late stages. Surgery is the mainstay of treatment. The technique of resection is standardized. After dissection of the retroperitoneal blood vessel, a retroperitoneal plane of dissection adjacent to the spinal foramina is established in between the layers of the abdominal wall. Complete resection with tumor-free resection margins is the primary goal in retroperitoneal sarcoma surgery. Preoperative assessment of pathoanatomical growth patterns with respect to retroperitoneal vascular structures--as well as to visceral and retroperitoneal organs--influences surgical strategies and thus the surgical outcome. Blood vessel replacement and a multivisceral en bloc approach improve the quality of resection. Blood vessel involvement is stratified in type I (arterial and venous involvement), type II (arterial involvement), type III(venous involvement), and type IV (no vascular involvement). Adjuvant and neoadjuvant treatment options (chemotherapy, targeted therapy, and radiation therapy) are currently being investigated. A prospective randomized phase III trial has shown a positive effect of neoadjuvant chemotherapy combined with regional hyperthermia in disease-free survival, response rate, and local control. Subsets of liposarcomas (myxoid and round cell type) are selectively responsive to novel drugs, such as trabectedin, a DNA-binding agent. Radiotherapy is applied in higher-grade locally advanced retroperitoneal STS. The optimal technique of delivering radiotherapy remains to be determined. The restricted number of patients with retroperitoneal STS and unsatisfying results in local tumor control and long-term survival indicate the need for multi-institutional cooperative studies. An international effort is required to improve the evidence level on multimodal treatment algorithms.

Retroperitoneal giant schwannoma eroding lumbal vertebra: A case report with a literature review

A huge schwannoma, located in the retroperitoneal space, is found very rarely. The main purpose of this paper is to present the case of a giant retroperitoneal schwannoma which partly invaded L4 vertebral body. The secondary purpose is to summarize the case-report articles on retroperitoneal schwannomas. A circumscribed heterogenic tumour was revealed on transabdominal sonography. It extended into the right retroperitoneal space. CT and MRI revealed a paravertebral tumour in the size of 11 cm × 9 cm, which is causing a partial lysis of L4 vertebral body (15% of vertebral capacity), expanding intravertebral foramen and filling the right retroperitoneal space. A preoperative core needle biopsy was performed and a benign schwannoma was diagnosed. A complete surgical excision of the tumour was achieved by a two-step operation. During the first step, the neurosurgeons made L4 hemilaminectomy, facetectomy and a transverse process resection by posterior extended approach. The general surgeons excised the residual retroperitoneal part of the tumour by midline transabdominal approach 10 days later. The diagnosis of benign schwannoma was verified histochemically. There were no sign of tumour recurrence or spine destabilization at the six-month follow-up. In conclusion, although majority of giant retroperitoneal schwannomas can be completely removed performing one-step operation, a preoperative consideration about rationality of two-step operation should be mandatory when tumour destructs a part of vertebral body. Our case shows that the combined two stage complete surgical excision of a giant retroperitoneal schwannoma, eroding 15% of L4 vertebra’s osseous capacity, is effective and does not have any negative influence on spinal stability.