Short- and long-term post-nephrectomy outcomes for retroperitoneal liposarcoma from a high-volume sarcoma center: a propensity score matching analysis

BACKGROUND

Multivisceral en bloc resection with the ipsilateral kidney is commonly performed in patients with retroperitoneal liposarcoma (RLPS). We evaluated the effect of nephrectomy on short- and long-term outcomes in patients with RLPS.

METHODS

Data from a prospectively maintained database of the Peking University Cancer Hospital Sarcoma Center between April 2011 and August 2022 were analyzed. We classified the RLPS patients who underwent surgery into nephrectomy group (NP) and non-nephrectomy group (non-NP). Patients were matched using a 1:1 propensity score to eliminate baseline differences between groups. Postoperative renal function outcomes, major morbidity, and mortality were analyzed to compare short-term outcomes after nephrectomy. Differences in local recurrence-free survival (LRFS) and overall survival (OS) were compared by Kaplan-Meier analysis with respect to oncological benefits.

RESULTS

In the matched cohort, patients in the NP group had significantly higher postoperative eGFR and CKD stages, but none required dialysis. Patients between NP and non-NP had a comparable major morbidity (p = 0.820) and 60-day mortality (p = 0.475). Patients in the NP group had a higher 5-year LRFS rates than those in the non-NP group (34.5 vs. 17.8%, p = 0.015), and similar 5-year OS rates (52.4 vs. 47.1%, p = 0.401). Nephrectomy was an independent risk factor for LRFS, but not for major morbidity or OS.

CONCLUSIONS

RLPS resection with nephrectomy is related to a mild progression of renal impairment; however, dialysis is rare. En bloc nephrectomy for complete resection of RLPS is safe and improves local control.

Gender Differences in Prognosis After Primary Resection for Retroperitoneal Liposarcoma

BACKGROUND

Current evidence regarding gender difference in retroperitoneal liposarcoma (RLPS) is scarce, so we sought to investigate whether gender may affect prognosis after primary resection of RLPS.

METHODS

We used the Surveillance, Epidemiology, and End Results (SEER) database to identify RLPS patients from January 1973 to December 2015. Multivariate cox proportional hazard analysis was adopted to generate adjusted hazard ratio (AHR) and 95% confidence intervals (CIs) of survival outcomes.

RESULTS

In total, 2108 RLPS patients, including 971 women and 1137 men, were identified, with a median follow-up of 45.0 (17.0-92.0) months. The 5-year and 10-year overall survival rates were 50.5% and 31.5% for men and 60.4% and 42.5% for women. The 5-year and 10-year disease-specific survival rates for men and women were 71.5%, 57.3% and 76.3%, 62.1%, respectively. We found men were associated with an increased risk of all-cause mortality (AHR 1.3, 95% CI 1.0-1.6, P = .017) but not disease-specific mortality (AHR 1.2, 95% CI .9-1.6, P = .246). The subgroup analyses revealed that men were associated with an increased risk of all-cause mortality in patients with low-grade tumors (AHR 1.8, 95% CI 1.3-2.5) or patients who received non-radical resection (AHR 1.6, 95% CI 1.2-2.1). In the subgroup of low-grade tumors, men were also associated with an increased risk of disease-specific mortality (AHR 2.0, 95% CI 1.2-3.3).

CONCLUSION

Men may have worse survival after primary resection of RLPS compared with women, especially in patients with low-grade tumors or patients who received non-radical resection. Gender-based disparities may deserve more attention in patients with RLPS.

Neoadjuvant Chemotherapy in Retroperitoneal Sarcoma: A National Cohort Study

INTRODUCTION

Management of retroperitoneal sarcoma (RPS) remains controversial, with the mainstay of treatment being surgery. While neoadjuvant radiation demonstrated no improvement in recurrence-free survival in a prospective randomized trial (STRASS), the role of neoadjuvant chemotherapy (NCT) remains unknown and is the subject of ongoing study (STRASS2).

METHODS

Patients who underwent surgical resection of high-grade RP leiomyosarcoma (LMS) or dedifferentiated liposarcoma (DDLS) were identified from the National Cancer Database (2006-2019). Predictors of NCT were analyzed using univariate and multivariate logistic regression analyses. Differences in 5-year survival were examined using the Kaplan-Meier (KM) method and by Cox proportional hazard modeling.

RESULTS

A total of 2656 patients met inclusion criteria. Fifty-seven percent of patients had DDLS and 43.5% had LMS. Six percent of patients underwent NCT. Patients who received NCT were younger (median age 60 vs 64 years, p < 0.001) and more likely to have LMS (OR 1.4, p = 0.04). In comparing NCT with no-NCT patients, there was no difference in 5-year overall survival (OS) on KM analysis (57.3% vs 52.8%, p = 0.38), nor was any difference seen after propensity matching (54.9% vs 49.1%, p = 0.48, N = 144 per group). When stratified by histology, there was no difference in OS based on receipt of NCT (LMS: 59.8% for NCT group, 56.6% for no-NCT, p = 0.34; DDLS: 54.2% for NCT group, 50.1% for no-NCT, p = 0.99).

CONCLUSION

In patients undergoing surgical resection of RP LMS or DDLS, NCT does not appear to confer an OS advantage. Prospective randomized data from STRASS2 will confirm or refute these retrospective data.

Survival of a patient with five recurrences of retroperitoneal liposarcoma over a period of 13 years: A case report and review

Retroperitoneal liposarcoma (RPLS) is a rare tumor that occurs in the retroperitoneal region and accounts for ~0.2% of all malignant tumor incidence. The present study describes the treatment of a surviving patient with RPLS that recurred five times in 13 years. This case has a long survival time and numerous relapses, which is a rare occurrence. The 40-year-old female patient was admitted to Shaoxing Second Hospital (Shaoxing, China) with an abdominal mass. Abdominal computed tomography (CT) scan revealed multiple liposarcoma recurrences in the abdominal, pelvic and retroperitoneal areas. As the diagnosis of RPLS was the fifth recurrence, cytoreductive surgery was performed and post-operative pathology suggested mixed liposarcoma. The patient underwent six cycles of doxorubicin and ifosfamide regimen chemotherapy and targeted therapy with anlotinib following surgery; no evidence of disease progression was found on abdominal CT scan during follow-up. The present study also reviewed the literature in terms of the clinical diagnosis, treatment, pathological characteristics and similar cases of liposarcoma with the aim of improving diagnosis and treatment.

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.

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.

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.

Patients with first recurrent retroperitoneal sarcoma that can be macroscopically completely resected can achieve comparable outcomes with that of primary patients after en bloc resection of tumor and adjacent organs

The outcomes of patients with primary retroperitoneal sarcoma (RPS) are significantly superior to those with recurrence. En bloc resection of tumor and adjacent organs is recommended in primary RPS. However, whether en bloc resection of tumor and adjacent organs can benefit recurrent patients or some recurrent patients is unclear. We compared the outcomes of patients with primary RPS, first recurrence (RPS-Rec1), and ≥2 recurrences (≥RPS-Rec2) to evaluate the value and criteria for en bloc resection of tumor and adjacent organs in recurrent cases. We evaluated the safety of en bloc resection of tumor and adjacent organs by assessing operation time, blood loss volume, postoperative morbidities (POM), and efficacy by comparing local recurrence and peritoneal metastasis (LR-PM), distant metastasis, progression-free survival (PFS), and overall survival (OS). A total of 101, 47, and 30 patients with primary RPS, RPS-Rec1, and ≥RPS-Rec2 were included, respectively. Recurrent RPS invaded more adjacent organs and surrounding fat tissue than primary RPS. The operation time, amount of blood loss, incidence of grade III–V POM, LR-PM rate, PFS, and OS in the RPS-Rec1 group were similar to those of the primary group, both of which were significantly superior to those of the ≥RPS-Rec2 group. Macroscopically incomplete resection and high-grade RPS rather than first recurrence were independent risk factors for LR-PM, PFS, and OS. In conclusion, the safety and efficacy of en bloc resection of tumor and adjacent organs in RPS-Rec1 were comparable with those in primary RPS but significantly superior to those of ≥RPS-Rec2. For RPS-Rec1, comparable outcomes to patients with primary RPS can be achieved, particularly in those in whom a macroscopically complete resection is achieved.

Microsurgical treatment of lumbar paravertebral tumors via lateral retroperitoneal approach: operative technique and a series of 6 patients

OBJECTIVE

To investigate the surgical techniques and postoperative therapeutic effectiveness of microsurgical treatment of lumbar paravertebral tumors via lateral retroperitoneal approach.

METHODS

The clinical data of 6 cases with lumbar paravertebral tumors treated by lateral retroperitoneal approach in the Neurosurgery department of Xuanwu Hospital, Capital Medical University were analyzed retrospectively. The mean operation time, blood loss, incision length, length of hospital stay, and the resection rate of paravertebral tumors were collected, and the score of The Ability to Perform Activities of Daily Living (ADL) and incidence of postoperative complications was recorded.

RESULTS

The operation time ranged from 56 to 181 min, with an average of (94.8 ± 48.3) minutes. The blood loss was between 5 and 100 ml, with an average of (31.7 ± 37.5) ml. The incision length was 6-7 cm, with an average of (6.7 ± 0.5) cm. The hospitalization length was between 5 and 11 days, with an average of (8.7 ± 2.6) days. The resection rate of paravertebral tumors was 100%. Postoperative pathological diagnosis results revealed 4 cases of schwannoma, 1 case of ganglioneuroma, and 1 case of malignant small round cell tumor. During the 3-month follow-up, there were no tumor recurrence, abdominal infection, incision infection, incisional hernia, or death, and there was no significant decrease in the ADL score compared with that before the operation.

CONCLUSION

The surgical treatment of lumbar paravertebral tumors via the lateral retroperitoneal approach has the advantages of the short operation time, minimally invasive procedures, quick postoperative recovery, and fewer complications.

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.

Retroperitoneal and Mesenteric Liposarcomas

Retroperitoneal liposarcomas are a rare entity and are comprised mostly of the well-differentiated and dedifferentiated subtypes. Eight-year survival ranges from 30% to 80% depending on histologic subtype and grade. Surgery is the cornerstone of treatment and compartment resection is the current standard. Mesenteric liposarcomas are extremely rare and comprise more high-grade lesions, with poorer prognosis of 50% 5-year overall survival. They are managed with a similar aggressive surgical approach. This review presents the current management of retroperitoneal and mesenteric liposarcomas.

National Trends in Treatment for Retroperitoneal Soft Tissue Sarcoma: A Modern Appraisal of Variability in Therapeutic Strategies

BACKGROUND

Little level 1 evidence exists to guide multimodality treatment in retroperitoneal soft tissue sarcoma (RPS), which may lead to significant variation in therapeutic approaches. This analysis aimed to describe national RPS treatment trends and explore potential variability among low-/high-volume hospitals (LVH/HVHs).

PATIENTS AND METHODS

In total, 5992 patients who underwent resection for primary RPS were retrospectively identified in the National Cancer Database (2004-2017). Time trend analyses examined rates of multivisceral resection (MVR), radiation, and chemotherapy use. LVHs were defined as those carrying out fewer than ten resections per year (N = 5433), whereas HVHs were defined as those carrying out ten or more (N = 559). Descriptive statistics and logistic regression models compared trends between groups.

RESULTS

MVR was more frequent at HVHs (63.7% versus 43.5%, p < 0.001). Use of radiation varied widely by hospital volume. HVHs more frequently employed preoperative radiation as compared with LVHs (14.7% versus 8.1%, p < 0.001). Throughout the study period, LVHs increased utilization of preoperative radiation (2.6% to 12.0%, p < 0.001) whereas rates at HVHs remained stable. Overall, LVHs utilized postoperative radiation significantly more frequently as compared with HVHs (14.7% versus 2.7%, respectively, p < 0.001). Postoperative radiation at LVHs remained stable until 2013 and sharply declined thereafter (16.7% to 6.9%, p < 0.001). Rates of postoperative radiation use at HVHs remained lower than those at LVHs at all time points.

CONCLUSIONS

Strategies for resection and radiation use at LVHs have trended towards those of HVHs. Current national implementation of preoperative radiation, MVR, and chemotherapy remains heterogeneous. These findings inform future trial design and support standardization of care.

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.

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.

Radical Versus Non-Radical Resection for Early-Stage Retroperitoneal Sarcoma: A Propensity Score-Matched Analysis

Background

The appropriate surgical procedure for early-stage retroperitoneal sarcoma (RPS) is unclear. Thus, we used a national database to compare the outcomes of radical and non-radical resection in patients with early stage RPS.

Methods

This retrospective study included 886 stage I RPS patients from 2004 to 2015 in the SEER database. Outcomes were compared using the multivariate Cox proportional hazards models and the results were presented as adjusted hazards ratio (AHR) with corresponding 95% confidence intervals (95%CIs). Propensity score-matched analyses were also performed for sensitive analyses.

Results

For the 886 stage I RPS patients, 316 underwent radical resection, and 570 underwent non-radical resection, with a median follow-up of 4.58 (2.73-8.35) years. No difference was observed in overall mortality (AHR 0.84, 95%CI 0.62-1.15; P = 0.28) or RPS-specific mortality (AHR 0.88, 95%CI 0.57-1.36; P = 0.56) between groups. The results were similar in propensity score-matching analyses. However, subgroup analysis revealed that radical resection was associated with significantly decreased risks of overall mortality in male (AHR 0.61, 95%CI 0.38-0.98; P = 0.04) and in patients with radiotherapy (AHR 0.56, 95%CI 0.32-0.98; P = 0.04).

Conclusion

Radical resection did not improve midterm survival outcomes compared with non-radical resection in overall patients with early stage RPS. However, male patients or patients who received radiotherapy might benefit from radical resection with improved overall survival.

Retroperitoneal sarcoma: the Transatlantic Australasian Retroperitoneal Sarcoma Working Group Program

PURPOSE OF REVIEW

The Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG) is a bottom-up clinical network established in 2013 with the goal of improving the care and outcomes of patients with retroperitoneal sarcoma (RPS). Here, we review the knowledge produced by this collaborative effort and examine the future potential of this group.

RECENT FINDINGS

TARPSWG has produced retrospective studies focused on patients with primary and recurrent RPS allowing a better understanding of patient prognosis, treatment outcomes and tumor biology. The group has played a pivotal role in a phase III randomized STudy of preoperative RAdiotherapy plus Surgery versus surgery alone for patients with Retroperitoneal Sarcoma (STRASS) trial, favoring patient recruitment and trial completion. A prospective registry for patients with primary RPS populated by TARPSWG members is ongoing. TARPSWG has created consensus papers with recommendations regarding the management of patients with primary, recurrent and metastatic RPS that collated the views of representatives of sarcoma centers from Europe, North America, Asia and Australia.

SUMMARY

Since its inception, TARPSWG has become a leading network in the field of RPS. It has made a major contribution to the world of RPS research and cares allowing to overcome the limitations related to the rarity of the disease through collaboration.

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.

Radical excision for retroperitoneal soft tissue sarcoma: A national propensity-matched outcomes analysis

BACKGROUND

Given the rarity of retroperitoneal soft tissue sarcoma, few studies have assessed if radical excision of retroperitoneal soft tissue sarcoma with adjacent organs improves survival outcomes. This propensity score-matched study aimed to evaluate the impact of radical excision versus resection of tumor alone.

METHODS

The National Cancer Database 2004 to 2015 was used to assess short- and long-term outcomes of resection of tumor alone versus radical excision (tumor plus ≥1 adjacent organs) via 1:1 propensity-matched analyses. Subgroup analyses included low-grade, high-grade, liposarcoma, leiomyosarcoma, adjacent organ involvement alone, localized tumors alone, and high-volume hospitals (≥10 resections/y). Multivariable logistic regression models identified factors associated with radical excision.

RESULTS

Comparison of propensity-matched groups (N = 1,139/group) revealed no significant differences in 30-day mortality, 90-day mortality, or overall survival (for all, P > .580). For all subgroup analyses comparing resection of tumor alone with radical excision, including localized tumors without organ invasion (N = 208/group), there were no identified differences in short- or long-term survival. Although it yielded lower R2 resection rates (P = .007), radical excision was associated with greater mean length of stay (P < .001).

CONCLUSION

Radical excision was not associated with improved retroperitoneal soft tissue sarcoma survival irrespective of grade, histology, hospital volume, or adjacent organ involvement. Resection of ostensibly involved adjacent viscera may increase morbidity without survival benefit. These results inform ongoing discussion regarding histology-tailored, situation-specific extent of retroperitoneal soft tissue sarcoma resections.

Unsupervised versus Supervised Identification of Prognostic Factors in Patients with Localized Retroperitoneal Sarcoma: A Data Clustering and Mahalanobis Distance Approach

The aim of this report is to unveil specific prognostic factors for retroperitoneal sarcoma (RPS) patients by univariate and multivariate statistical techniques. A phase I-II study on localized RPS treated with high-dose ifosfamide and radiotherapy followed by surgery (ISG-STS 0303 protocol) demonstrated that chemo/radiotherapy was safe and increased the 3-year relapse-free survival (RFS) with respect to historical controls. Of 70 patients, twenty-six developed local, 10 distant, and 5 combined relapse. Median disease-free interval (DFI) was 29.47 months. According to a discriminant function analysis, DFI, histology, relapse pattern, and the first treatment approach at relapse had a statistically significant prognostic impact. Based on scientific literature and clinical expertise, clinicopathological data were analyzed using both a supervised and an unsupervised classification method to predict the prognosis, with similar sample sizes (66 and 65, resp., in casewise approach and 70 in mean-substitution one). This is the first attempt to predict patients' prognosis by means of multivariate statistics, and in this light, it looks noticable that (i) some clinical data have a well-defined prognostic value, (ii) the unsupervised model produced comparable results with respect to the supervised one, and (iii) the appropriate combination of both models appears fruitful and easily extensible to different clinical contexts.

Anterior Approach to En Bloc Resection in Left-Sided Retroperitoneal Sarcoma with Adjacent Organ Involvement: A Study of 25 Patients in a Single Center

Background

There is no standard surgical approach for the management of retroperitoneal sarcoma. The aim of this clinical study was to describe the experience of an anterior approach to en bloc resection in left-sided retroperitoneal sarcoma with adjacent organ involvement.

Material/Methods

This retrospective clinical study included 25 patients who were diagnosed with left-sided retroperitoneal sarcoma and underwent tumor resection at a single center between May 2012 and July 2017. All patients had tumors that were adjacent to the left colon, pancreas, left kidney, left adrenal gland, and psoas major; some of the tumors were adjacent to the diaphragm, stomach, and small intestine. An anterior approach was used to remove the left-sided retroperitoneal tumor with the adhesive organs en bloc, an approach that is described in detail. The value of this surgical approach was evaluated based on the histopathological findings, postoperative complications, and patient follow-up.

Results

The median number of resected organs, in addition to the retroperitoneal tumor, was 8 (range, 6–10). Complete macroscopic tumor resection was achieved in 23 cases (92%). Twenty-four patients (96%) had tumor infiltration of at least one organ or the surrounding fat. Three patients (12%) experienced Grade III and IV postoperative morbidities. The one-year disease-free survival rate was 91.3% among patients with macroscopically complete resections. The one-year overall survival rate was 83.2%.

Conclusions

In selected patients, left-sided retroperitoneal sarcoma associated with local organ involvement can be surgically managed using an anterior approach with en bloc resection of adjacent organs.

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.

Dedifferentiated Liposarcoma Mimicking a Primary Colon Mass

Dedifferentiated liposarcoma is typically a nonlipogenic high-grade sarcoma that arises from well-differentiated liposarcoma. It most commonly presents as a large mass in the retroperitoneum. Significant involvement of the gastrointestinal tract by dedifferentiated liposarcoma is uncommon. We present a unique case of dedifferentiated liposarcoma radiographically mimicking a primary colon mass with resulting intussusception; stranding of the adjacent adipose tissue was presumed to be a secondary reactive change. On histopathologic analysis of the hemicolectomy specimen, a high-grade sarcoma was seen growing through the colonic wall, and the majority of the surrounding pericolonic adipose tissue was actually composed of well-differentiated liposarcoma with characteristic fibrous bands rather than benign fat with reactive fibrosis. This case raises awareness that well-differentiated liposarcoma and dedifferentiated liposarcoma can rarely present as a primary intestinal mass mimicking colon cancer or other more common entities. When radiographic examination shows a perigastrointestinal or retroperitoneal fatty mass and/or stranding of the fat adjacent to a solid gastrointestinal mass, this unusual scenario should be considered in the radiologic differential diagnosis. Pathologists should keep dedifferentiated liposarcoma in the initial histologic differential diagnosis for any high-grade spindle cell tumor of the retroperitoneum or intra-abdominal visceral organs.

Histology-based Classification Predicts Pattern of Recurrence and Improves Risk Stratification in Primary Retroperitoneal Sarcoma

OBJECTIVE

To determine the prognostic significance of histologic type/subtype in a large series of patients with primary resected retroperitoneal sarcoma.

BACKGROUND

The histologic diversity and rarity of retroperitoneal sarcoma has hampered the ability to predict patient outcome.

METHODS

From a single-institution, prospective database, 675 patients treated surgically for primary, nonmetastatic retroperitoneal sarcoma during 1982 to 2010 were identified and histologic type/subtype was reviewed. Clinicopathologic variables were analyzed for association with disease-specific death (DSD), local recurrence (LR), and distant recurrence (DR).

RESULTS

Median follow-up for survivors was 7.5 years. The predominant histologies were well-differentiated liposarcoma, dedifferentiated liposarcoma, and leiomyosarcoma. Five-year cumulative incidence of DSD was 31%, and factors independently associated with DSD were R2 resection, resection of 3 or more contiguous organs, and histologic type. Five-year cumulative incidence for LR was 39% and for DR was 24%. R1 resection, age, tumor size, and histologic type were independently associated with LR; size, resection of 3 or more organs, and histologic type were independently associated with DR. Liposarcoma and leiomyosarcoma were associated with late recurrence and DSD (as long as 15 years from diagnosis). For solitary fibrous tumor, LR was uncommon (<10%), but early distant recurrence was common (36% at 5 years). Nomograms were developed to predict DSD, LR, and DR.

CONCLUSIONS

Histologic type/subtype is the most important independent predictor of DSD, LR, and DR in primary retroperitoneal sarcoma. Histology predicts the pattern and incidence of LR and DR and will aid in more accurate patient counseling and selection of patients for adjuvant therapy trials.

Is multivisceral resection in locally advanced gastrointestinal stromal tumours an acceptable strategy?

BACKGROUND

Gastrointestinal stromal tumours (GISTs) represent the most common mesenchymal tumour of the gastrointestinal tract. Although the efficacy of targeted therapy cannot be over-emphasized, surgery remains the only curative primary treatment for patients with localized disease. The median size of GIST at diagnosis is approximately 5-7 cm; however, it is not uncommon for tumours to be as large as 30-40 cm and involving multiple viscera.

METHODS

Data were retrospectively collected from patients with GISTs treated at the Singapore General Hospital and the National Cancer Centre Singapore over a 15-year period. Standard resection of GIST without any additional organ removal was termed as a single organ resection (SOR). If the tumour was adjacent to another organ, necessitating the removal of more than one organ, the procedure was defined as a multivisceral resection (MVR). We aim to evaluate the role of MVR in the management of large GISTs.

RESULTS

A total of 187 patients underwent curative surgery for GIST between January 2000 and January 2014. Of the 187 patients, 40 (21%) underwent MVR whereas 147 (79%) had SOR. Patients in the MVR group had significantly larger tumour sizes (P < 0.001) yet R0 and R1 resection was achieved in all patients, and no intra-peritoneal rupture was reported. On comparison of MVR versus SOR groups, there was no significant difference in in-hospital morbidity and mortality.

CONCLUSION

MVR may be required to achieve negative margins in patients with large GISTs, and can be performed with acceptable morbidity and mortality.

[Intra-abdominal and retroperitoneal sarcomas]

Sarcomas are a heterogeneous group of rare tumors that originate from mesenchymal tissue. Radical R0 resection is the only curative option, which is especially challenging in retroperitoneal or intra-abdominal sarcomas. This article describes the current data on optimal interdisciplinary and primarily surgical therapy of visceral sarcomas. Surgical resection of retroperitoneal sarcomas must be performed according to the principle of radical compartmental resection, i.e. with complete excision of the mass along with en bloc visceral resection of adjacent organs and tissues covering the tumor, which also contains any not obviously infiltrated neighboring organs. The main objective is R0 resection without opening the tumor capsule in the primary operation because the best long-term results can be achieved with this approach.

Extended resection including adjacent organs and Ki-67 labeling index are prognostic factors in patients with retroperitoneal soft tissue sarcomas

BACKGROUND

Because retroperitoneal soft tissue sarcomas (RPS) are extremely rare, there is a significant lack of clinicopathologic information to optimize the treatment strategy. The aim of this study was to evaluate the prognostic factors in RPS, with particular focus on the Ki-67 labeling index (LI).

METHODS

We included the data from a total of 23 patients who received treatment for primary RPS at a single center. The variables analyzed in this study included tumor size, histological type, malignancy grade, necrosis, mitosis, and Ki-67 LI. Kaplan-Meier and Cox proportional regression analyses of overall survival (OS) were performed to identify significant prognostic variables.

RESULTS

Of the 23 patients who underwent surgical resection, 9 (39%) underwent simple resection of the tumor and 14 (61%) extended resection including the adjacent organs. In the univariate analysis, a simple tumor resection and a high Ki-67 LI were associated with shorter OS. The multivariate analysis revealed that simple tumor resection and a high Ki-67 LI were independent negative prognostic factors for OS.

CONCLUSIONS

Our results suggested that combined resection of RPS and its adjacent organs improved OS. Pathologically, a high Ki-67 LI was significantly associated with negative prognosis.

Surgical outcome and patterns of recurrence for retroperitoneal sarcoma at a single centre

INTRODUCTION

Retroperitoneal sarcoma is a surgically managed condition that can recur locally following macroscopically complete resection. Owing to the low incidence of the condition, advances in treatment are reported infrequently but complete compartmental resection and adjuvant or neoadjuvant radiotherapy are areas under investigation. Given the practical difficulty of randomised trials, observational data can highlight advantages from progressive treatment approaches.

METHODS

A retrospective database of consecutive retroperitoneal sarcoma resections performed at a single referral centre between March 1997 and March 2013 was interrogated. Histological, radiological and clinical data were collected. Univariate and multivariate analyses for disease free and overall survival were performed to establish independent predictors of disease recurrence and patient survival.

RESULTS

A total of 79 patients underwent 90 resections (63 primary). The mean five-year overall and disease free survival rates were 55.3% and 24.8% respectively. Higher patient age, high tumour grade, presence of extraretroperitoneal disease and invasive tumour phenotype were found to significantly predict survival following multivariate analysis. Half (50%) of the tumours displayed invasive behaviour on histopathology and 42% of locoregional recurrence was intraperitoneal.

CONCLUSIONS

Retroperitoneal sarcoma is commonly an infiltrative tumour and often recurs outside of the retroperitoneum. These features limit the therapeutic impact of interventions that focus on gaining local control such as complete compartmental resection and radiotherapy. It seems likely that future advances in the management of this cancer will involve new systemic agents to treat this frequently systemic disease.

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.

Long-term morbidity after multivisceral resection for retroperitoneal sarcoma

Background

More than 60 per cent of patients treated surgically for primary retroperitoneal sarcoma survive for at least 5 years. Extended surgical resection has been proposed for primary disease, but long-term morbidity data are lacking. A cross-sectional study was conducted to assess the long-term morbidity of patients undergoing surgery for retroperitoneal sarcoma.

Methods

Patients operated on between January 2002 and December 2011 were eligible for the study. Long-term morbidity was evaluated based on a semistructured clinical interview. Lower limb function was assessed by means of the Lower Extremity Functional Scale (LEFS), a self-report questionnaire with a total score ranging from 0 (low functioning) to 80 (high functioning). Pain was investigated by means of the Brief Pain Inventory – Short Form, with pain intensity scores reported on a scale from 0 (no pain) to 10 (worst pain).

Results

Some 243 patients underwent surgery, and 101 of 160 patients who were alive at the time of the investigation responded to the study invitation letter. Finally, 95 patients were enrolled in the study. Sensory impairment of the limbs was reported in 72 patients (76 per cent). The median LEFS score was 60 (i.q.r. 43–73). Mean scores for the pain intensity items varied from 1·23 to 2·68. In multivariable analysis, there was no difference in median levels of creatinine at survey between patients who did or did not undergo nephrectomy (difference between median values 13 (95 per cent c.i. −4 to 30) µmol/l; P = 0·170).

Conclusion

Severe chronic pain and lower limb motor impairment after multivisceral resection for retroperitoneal sarcomas are rare. Long-term renal function is not significantly impaired when nephrectomy is performed.

Personalizing surgical margins in retroperitoneal sarcomas

Retroperitoneal sarcomas are a group of diseases that behave differently from one another. Well-differentiated liposarcomas have an indolent biology but show a tendency to recur locally even years after primary resection. Dedifferentiated liposarcomas are characterized by a very high local recurrence risk, while the metastatic risk mainly depends on the histological characteristics of the dedifferentiated component. In leiomyosarcomas, hematogenous spread informs prognosis while local recurrences are far less common. Surgery is the cornerstone of treatment of all retroperitoneal sarcoma subtypes and its quality is the only treatment-related factor able to improve the oncological outcome. A frontline extended surgical approach is all the more critical in subtypes in which local control directly impacts prognosis.

Metastasis in dedifferentiated liposarcoma: Predictors and outcome in 148 patients

OBJECTIVE

To describe the pattern of dedifferentiated liposarcoma (DDLPS) metastases and to analyze their predictors and outcome.

MATERIALS AND METHODS

In this retrospective study, we reviewed the imaging and clinical records of all consenting patients with histopathology-confirmed DDLPS seen from 2000 through 2012. The predictive value of clinical and histopathologic parameters for metastasis later in the disease course was analyzed using univariate and multivariate analyses. Survival of patients with and without metastasis was compared using Log-rank test.

RESULTS

Records of 148 patients (57 women, 91 men; mean age 59 years, range 30-87 years) were reviewed. Distant metastases were observed in 44/148 patients (29.7%), 9/44 (20.5%) at presentation and 35/44 (79.5%) developing them later at a median interval of 8 months (IQR = 0.80-26 months). Median duration of follow-up was 38 months (IQR = 18-74 months) with 77/148 patients (31 with metastases) deceased at the time of analysis. Median survival was 28 months (IQR = 10-56 months) for patients with metastases and 38 months (IQR, 17-65 months) for patients without metastases (p = 0.0123, Log-Rank test; Hazard ratio 1.79 [95% confidence interval 1.11-2.84]). Lung was the most common site of metastases (33 patients, 22.3%). On univariate analysis, grade and local recurrence were associated with subsequent risk of metastasis where as age, tumor size, site, de novo dedifferentiation, number of previous surgical resections, margin positivity and chemoradiation were not. On multivariate analysis, high tumor grade (p-value = 0.0005, OR 5.05; 95% CI 2.01-13.48) and local recurrence (p-value = 0.0025, OR 4.46; 95% CI 1.67-13.40) predicted metastasis.

CONCLUSION

Lung was most frequent site of DDLPS metastases. Risk of developing metastatic disease was statistically associated with tumor grade and local recurrence. Metastatic disease was associated with decreased survival.

Retroperitoneal sarcomas: patterns of care at diagnosis, prognostic factors and focus on main histological subtypes: a multicenter analysis of the French Sarcoma Group

BACKGROUND

Retroperitoneal sarcomas (RPS) are heterogeneous. No previous study has investigated the impact of specialized surgery, evaluated locoregional relapse (LRR), abdominal sarcomatosis and distant metastatic relapse as separate events, or considered histological subtypes separately. This study addresses these specific points in a homogeneous cohort of patients with completely resected primary RPS.

PATIENTS AND METHODS

We conducted a retrospective analysis of adult patients diagnosed with a RPS between 1 January 1988 and 31 December 2008 and eventually referred to one of 12 centers of the French Sarcoma Group. All cases were centrally reviewed by an expert pathologist.

RESULTS

Five hundred eighty-six patients were included. Median follow-up was 6.5 years [95% confidence interval (CI) 5.9-7.1]. Five hundred thirty-seven patients had localized disease and 389 patients (76%) had macroscopically complete resection of the tumor. In this latter group, the 5-year LRR-free survival rate was 46% [41-52] and the 5-year overall survival (OS) rate was 66% [61-71]. In multivariate analysis, gender, adjacent organ involvement, specialization of the surgeon, piecemeal resection and perioperative radiotherapy were independently associated with LRR. Specialization of the surgeon and piecemeal resection were independently associated with abdominal sarcomatosis whereas histology and adjacent organ involvement were independently associated with distant metastasis. Age, gender, grade, adjacent organ involvement and piecemeal resection were significantly associated with OS. Prognostic factors for LRR and OS were analyzed in well-differentiated and dedifferentiated liposarcomas and leiomyosarcomas. Grade 3 was an independent prognostic factor for OS of dedifferentiated liposarcomas.

CONCLUSION

This study underlines the crucial role of pretherapeutic assessment and meticulous histological examination of RPS as well as the need to consider histological subtypes separately. Surgery in a specialized center and avoidance of piecemeal resection stand out as the two most important prognostic factors for RPS and highlight the importance of treating these patients in specialized centers.

Thoracopleuropneumonectomy with riblike reconstruction for recurrent thoracic sarcomas

BACKGROUND

Large intrathoracic tumors may occasionally present with massive infiltration of the lung and chest wall that would require pneumonectomy and total removal of the rib cage to obtain radical surgical excision, but this operation carries a prohibitive risk of death for cardiopulmonary failure in the absence of adequate chest wall reconstruction.

METHODS

We report here four consecutive cases of thoracopleuropneumonectomy (TPP) with en-bloc resection of the entire lung, chest wall, and diaphragm and immediate riblike reconstruction for recurrent thoracic sarcomas. Patients had undergone the initial thoracic surgical resection with curative intent 2-14 years before TPP. There was no postoperative mortality, and all patients were alive and free of disease 8-21 months after TPP.

RESULTS

To our knowledge, this is the first report in the medical literature of such an extensive operation, demonstrating technical feasibility, tolerability, and efficacy of one-stage resection and reconstruction by a semirigid three-dimensional riblike prosthesis modeled on a human-derived aluminum cast.

CONCLUSIONS

Selected patients with advanced low-intermediate thoracic sarcomas are the ideal candidates for this extreme procedure, to maximize the chance of long-term tumor control and possibly cure.