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

Comparing Multivisceral Resection with Tumor-only Resection of Liposarcoma Using the Win Ratio

BACKGROUND

Multivisceral resection of retroperitoneal liposarcoma (LPS) is associated with increased morbidity and may not confer a survival benefit compared with tumor-only (TO) resection. We compared both approaches using a novel statistical method called the "win ratio" (WR).

METHODS

Patients who underwent resection of LPS from 2004 to 2015 were identified from the National Cancer Database. Multivisceral resection was defined as removal of the primary site in addition to other organs. The WR was calculated based on a hierarchy of postoperative outcomes: 30-day and 90-day mortality, long-term survival, and severe complication.

RESULTS

Among 958 patients (multivisceral 634, TO 324) who underwent resection, the median age was 63 years (interquartile range [IQR] 54-71) with a median follow-up of 51 months (IQR 30-86). There was no difference in the WR among patients who underwent TO versus multivisceral resection in the matched cohort (WR 0.82, 95% confidence interval [CI] 0.61-1.10). In patients aged 72-90 years, those who underwent multivisceral resection had 36% lower odds of winning compared with patients undergoing TO resection (WR 0.64, 95% CI 0.40-0.98). A subgroup analysis of patients classified as not having adjacent tumor involvement at the time of surgery revealed that those patients who underwent multivisceral resection had 33% lower odds of winning compared to TO resection (WR 0.67, 95% CI 0.45-0.99).

CONCLUSIONS

Based on win-ratio assessments of a hierarchical composite endpoint, multivisceral resection in patients without adjacent tumor involvement may not confer improved outcomes. This method supports the rationale for less invasive resection of LPS in select patients, especially older patients.

R0 surgical resection of giant dedifferentiated retroperitoneal liposarcomas in the COVID era with and without nephrectomy: A case report

Retroperitoneal sarcomas (RPSs) are rare findings that can grow into large masses without eliciting severe symptoms. At present, surgical resection is the only radical therapy, whenever it can be performed with the aim to achieve a complete removal of the tumor. The present report describes two consecutive cases of RPSs that resulted in dedifferentiated liposarcomas (DDLPSs) and these patients underwent R0 surgical resection with and without a nephron-sparing procedure. The diagnostic workup, the surgical approach, the impact of late surgical management due to the COVID pandemic and the latest literature on the topic are discussed and analyzed. The patients, who refused to undergo any medical examination during the prior 2 years due to the COVID pandemic, were admitted to Federico II University Hospital (Naples, Italy) complaining about weight loss and general abdominal discomfort. In the first case, a primitive giant abdominal right neoplasm of retroperitoneal origin enveloping and medializing the right kidney was observed. The second patient had a similar primitive retroperitoneal giant left neoplasm, which did not affect the kidney. Given the characteristics of the masses and the absence of distant metastases, after a multidisciplinary discussion, radical surgical removal was carried out for both patients. The lesions appeared well-defined from the surrounding tissues, and markedly compressed all the adjacent organs, without signs of infiltration. In the first patient, the right kidney was surrounded and undetachable from the tumor and it was removed en bloc with the mass. The second patient benefited from a nephron-sparing resection, due to the existence of a clear cleavage plane. The postoperative courses were uneventful. Both the histological examinations were oriented towards a DDLPS and both patients benefited from adjuvant chemotherapy. In conclusion, the treatment of giant RPS is still challenging and requires multidisciplinary treatment as well as, when possible, radical surgical removal. The lack of tissue infiltration and the avoidance of excision or reconstruction of major organs (including the kidney) could lead to an easier postoperative course and an improved prognosis. When possible, surgical management of recurrences or incompletely resected masses must be pursued. Since the COVID pandemic caused limited medicalization of a number of population groups and delayed diagnosis of other oncologic diseases, an increased number of DDLPSs could be expected in the near future.

Indicators of clinical performance in monitoring soft tissue sarcoma management: a population-based perspective

Background

Soft tissue sarcomas (STS) are rare malignancies which prognosis varies significantly by primary site, histological subtype, and tumor stage. Their low incidence, and the complexity of their clinico-pathological characteristics demand standardized, cancer-tailored diagnostics and therapies managed at high-volume, multidisciplinary care centers. This study evaluates the quality of STS management in north-east Italy (Veneto Region) through a list of ad hoc defined clinical indicators.

Methods

This population-based study concerns all incident cases of STS in 2018 (214 cases) recorded in the adult population censored by the Veneto's regional Cancer Registry. Based on the international literature, a multidisciplinary working group of experts identified a set of indicators for monitoring the quality of diagnostic, therapeutic, and end-of-life clinical interventions. The quality of care was assessed by comparing the reference thresholds with the indicators' values achieved in clinical practice.

Results

Diagnostic procedures showed poor adherence to the thresholds, with a low percentage of histological diagnoses validated by a second opinion. The indicators relating to the surgical treatment of superficial, small, low-grade STS, or of medium, high-grade STS of the head-neck, trunk, or limbs were consistent with the thresholds, while for intermediate, high-grade (large-sized, deep) and retroperitoneal STS they fell significantly below the thresholds.

Conclusion

A critical evaluation of the clinical indicators allowed to uncover the procedures needing corrective action. Monitoring clinical care indicators improves cancer care, confirms the importance of managing rare cancers at highly specialized, high-volume centers, and promotes the ethical sustainability of the healthcare system.

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.

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.