Retroperitoneal Soft Tissue Sarcoma Research Articles

Retroperitoneal Soft Tissue Sarcoma: Emerging Therapeutic Strategies.

Retroperitoneal soft tissue sarcoma (RPS) is a rare and heterogenous disease for which surgery is the cornerstone of treatment. However, the local recurrence rate is much higher than in soft tissue sarcoma of the extremities since wide resection is usually unfeasible in RPS due to its large size, indistinct tumour borders, anatomical constraints and the thinness of the overlying peritoneum. Local recurrence is the leading cause of death for low-grade RPS, whereas high-grade tumours are prone to distant metastases. In recent decades, the role of emerging therapeutic strategies, such as more extended surgery and (neo)adjuvant treatments to improve oncological outcome in primary localised RPS, has been extensively investigated. In this review, the recent data on the evolving multidisciplinary management of primary localised RPS are comprehensively discussed. The heterogeneity of RPS, with their different histological subtypes and biological behaviour, renders a standard therapeutic 'one-size-fits-all' approach inappropriate, and treatment should be modified according to histological type and malignancy grade. There is sufficient evidence that frontline extended surgery with compartmental resection including all ipsilateral retroperitoneal fat and liberal en bloc resection of adjacent organs and structures, even if they are not macroscopically involved, increases local tumour control in low-grade sarcoma and liposarcoma, but not in leiomyosarcoma for which complete macroscopic resection seems sufficient. Additionally, preoperative radiotherapy is not indicated for all RPSs, but seems to be beneficial in well-differentiated liposarcoma and grade I/II dedifferentiated liposarcoma, and probably in solitary fibrous tumour. Whether neoadjuvant chemotherapy is of benefit in high-grade RPS remains unclear from retrospective data and is subject of the ongoing randomised STRASS 2 trial, from which the results are eagerly awaited. Personalised, histology-tailored multimodality treatment is promising and will likely further evolve as our understanding of the molecular and genetic characteristics within RPS improves.

Retroperitoneal soft tissue sarcomas: Predictive factors for incomplete resection

Retroperitoneal soft tissue sarcomas: Predictive factors for incomplete resection

1932P First in human trial of CEB-01 for retroperitoneal soft tissue sarcoma

1932P First in human trial of CEB-01 for retroperitoneal soft tissue sarcoma

Does compartmental resection really impact retroperitoneal soft tissue sarcomas? A retrospective analysis from a Single Referral Center

BackgroundThe treatment of choice for retroperitoneal soft tissue sarcomas (RPS) is surgical resection; the outcomes with more radical surgeries, notably compartmental resection, remains a subject of debate. Arguments against it, include the complexity of the technique and high morbidity. Materials and methodsA retrospective analysis of cases treated in a single center from January 2010 to December 2019 is presented. Two time periods were evaluated: 2010–2015 and 2016–2019, corresponding to before and after the implementation of routine compartmentectomy. We evaluated the short- and long-term outcomes of compartmental resection compared to limited surgeries through a multivariate analysis of prognostic factors. ResultsA total of 176 cases were included, of which 102 met the inclusion criteria. The sex distribution was similar. The average age was 52.9 years, and the average tumor size was 24.5 cm. The most frequent histology was liposarcoma (65.7%), followed by leiomyosarcoma (12.7%), and malignant peripheral nerve sheath tumor (8.8%). The median follow-up period was 40 months. We found a lower local recurrence in the group treated in the recent period (compartmentectomy) 42.3% vs 20% p = 0.007. The median overall survival (OS) was 38.7 months, and there was no difference in distant recurrence between the two time periods. Postoperative morbidity was higher in the recent period (25% vs 10% p 0.041), with no difference in 30-day mortality. ConclusionsThe implementation of extensive surgery, specifically compartmentectomy, for retroperitoneal sarcomas has been linked to reduced local recurrence. We recommend considering this surgical approach for RPS in alignment with current expert consensus guidelines, as highlighted by the updated TARPSWG consensus.

Survival nomograms for patients with retroperitoneal soft tissue sarcoma based on the SEER database and an external cohort.

Retroperitoneal soft tissue sarcoma (RPS) is a quite rare disease,and new nomograms need to be constructed to predict the overall survival (OS) and cancer specific survival (CSS) of RPS patients. The clinical data of patients with RPS were extracted from the Surveillance, Epidemiology, and End Results (SEER) database and authors' hospital. The LASSO method and COX proportional hazard regression were used to screen independent risk factors which were used to develop nomograms. Nomograms was evaluated in terms of discrimination by consistency index (C-index) and calibration curve. Decision curve analysis (DCA) and integrated discrimination index (IDI) were performed to assess net benefit and the improvement of model, respectively. Kaplan-Meier method and log-rank test were applied to compare the survival difference between groups. A total of 1164 cases were enrolled which were divided into training cohort (n = 814) and internal validation cohort (n = 350) at a 7:3 ratio. The discrimination of nomograms were good with C-index of 0.728 (95%CI = 0.704-0.752, R2 = 0.270), 0.754 (95%CI = 0.729-0.779, R2 = 0.281) for OS and CSS, respectively. Calibration curve showed good predictive accuracy of nomograms both in internal and external validation cohort, and IDI indicated that nomograms perform well than AJCC stage. Kaplan Meier curve and log-rank test uncovered statistically significance survival difference between high- and low-risk groups with P < 0.001 in terms of OS and CSS. Novel nomograms predicting the OS and CSS of RPS patients perform well in discrimination, calibration, clinical benefit and IDI. These nomograms may facilitate risk stratification and making clinical decision.

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

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. 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. 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. 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.

Long-term quality of life after resection of retroperitoneal soft tissue sarcoma

IntroductionRetroperitoneal soft tissue sarcoma (RPS) is characterized by high recurrence rates. Since complete tumor resection, often necessitating multivisceral resection, enables long-term survival in both primary and recurrent disease, health related quality of life (QoL) after RPS resection has attracted increasing interest. However, data regarding this topic is limited. Here, we multidimensionally assessed long-term QoL after RPS resection. MethodsFive previously validated (1. EORTC QLQ-C30, 2. WEMWBS, 3. FoP-Q-SF, 4. PC-PTSD, 5. Pro-CTCAE) were sent to patients having undergone resection of primary, recurrent and metastasized RPS at Heidelberg University Hospital between 10/2001 and 12/2020. Multivariable linear regression models were used to test associations between clinical/demographic variables and patient reported outcomes (PROs). ResultsQuestionnaires were answered by 127 patients (71% response rate). The median interval between RPS diagnosis and assessment of PROs was 80 months. The overall Global Health score was 64.1 and comparable to the general German population. RPS patients reported deficits regarding emotional and social functioning, whereas physical limitations were less pronounced. Besides diarrhea, abdominal symptoms were comparable to the overall population. Tumor recurrences, the number of surgeries, multivisceral resections or postoperative complications did not significantly affect long-term QoL ratings. ConclusionRPS patients rate their QoL relatively high, even after multiple and multivisceral resections. Psychosocial well-being should be monitored in follow-up sessions to offer tailored support if necessary, thus improving postoperative care.

A century of retroperitoneal soft-tissue sarcoma research: From single center experience to precision oncology? A bibliometric analysis of past, present, and future perspectives

BackgroundIncreasing publication numbers in the biomedical field led to an improvement of patient care in many aspects but are challenging for scientists when integratively processing data of their fields. Using bibliometric analyses, the present study assesses the productivity and predominant topics in retroperitoneal soft-tissue sarcoma (RPS) research across the past 122 years, thereby identifying crucial questions to address in future RPS research. MethodsUsing the Web of Science Core Collection, 1018 RPS-associated publications from 1900 to 2022 were identified and analyzed regarding key bibliometric variables using the Bibliometrix R package and the VOSviewer software. ResultsA continuous increase in RPS-associated publication numbers can be noticed over the time, which is strongly pronounced from 2005 onwards, and is characterized by a multinationally driven collaborative clinical research focus. The research primarily reflects progression regarding surgical techniques, histology-based therapy, radiotherapy regimens, and identification of prognostic clinicopathological factors. This progression is accompanied with improved overall survival of RPS patients. However, a paucity of RPS-specific basic/translational research indicates that such research might be additionally needed to better understand the pathophysiology of RPS and with that to enable the development of personalized therapies and to further improve patient outcome. ConclusionIncreasing publication numbers of multinationally driven clinical RPS research are accompanied with improved overall survival of RPS patients, highlighting the importance of international collaborations to facilitate future clinical trials. However, this bibliometric analysis reveals a lack of RPS-specific basic/translational research which is needed to further improve patient outcome in the context of precision oncology.

Epidemiology, pathological characteristics and survival of retroperitoneal soft‑tissue sarcomas compared with non‑retroperitoneal soft tissue sarcomas.

Retroperitoneal soft-tissue sarcomas (RPS) are rare forms of mesenchymal tumors that account for ~0.15% of all malignancies. The purpose of the present study was to determine the differences between RPS and non-RPS anatomopathological and clinical features and to analyze whether the hazard ratio for short-term mortality differs between patients with RPS and non-RPS, after adjusting for differences in baseline anatomopathological and clinical features. The Veneto Cancer Registry, a high-resolution population-based dataset spanning the regional population, was used as a data source for the analysis. The current analysis focuses on all incident cases of soft-tissue sarcoma recorded by the Registry from January 1, 2017 to December 31, 2018. A bivariate analysis was carried out to compare demographic and clinical characteristics in RPS and non-RPS. Short-term mortality risk was analyzed by primary tumor site. The significance of variations in survival by site group was determined using Kaplan-Meier curves and the Log-rank test. Finally, Cox regression was used to assess the hazard ratio for survival by sarcoma group. RPS accounted for 22.8% of the total sample (92 out of 404 cases). The mean age at diagnosis was 67.6 years for RPS vs. 63.4 for non-RPS; 41.3% of RPS were >150 mm vs. 5.5% for non-RPS. Stages III and IV were more prevalent in RPS (53.2 vs. 35.6%), despite the fact that, in both groups, advanced stages are the most common onset at diagnosis. Regarding surgical margins, the present study showed that R0 is the most prevalent in non-RPS (48.7%), while R1-R2 is the most frequent in patients with RPS (39.1%). The 3-year mortality rate for retroperitoneum was 42.9 vs. 25.7%. Comparing RPS and non-RPS, the multivariable Cox model showed a hazard ratio of 1.58 after adjusting for all other prognostic factors. RPS clinical and anatomopathological characteristics differ from those of non-RPS. Overall, despite adjusting for other prognostic factors, the retroperitoneum site was an independent prognostic factor associated with a worse overall survival in sarcoma patients compared with other sites.

Preoperative Dose-Escalated Intensity-Modulated Radiotherapy (IMRT) and Intraoperative Radiation Therapy (IORT) in Patients with Retroperitoneal Soft-Tissue Sarcoma: Final Results of a Clinical Phase I/II Trial.

To report the final results of a prospective, one-armed, single-center phase I/II trial (NCT01566123). Between 2007 and 2017, 37 patients with primary or recurrent (N = 6) retroperitoneal sarcomas were enrolled. Treatment included preoperative IMRT of 45-50 Gy with a simultaneous integrated boost of 50-56 Gy, surgery and IORT. The primary endpoint was local control (LC) at 5 years. The most common histology was dedifferentiated liposarcoma (51%), followed by leiomyosarcoma (24%) and well-differentiated liposarcoma (14%). The majority of lesions were high-grade (FNCLCC G1: 30%, G2: 38%, G3: 27%, two missing). Five patients were excluded from LC analysis per protocol. The minimum follow-up of the survivors was 62 months (median: 109; maximum 162). IORT was performed for 27 patients. Thirty-five patients underwent gross total resection; the pathological resection margin was mostly R+ (80%) and, less often, R0 (20%). We observed 10 local recurrences. The 5-year LC of the whole cohort was 59.6%. Eleven patients received a dose > 50 Gy plus IORT boost; LC was 64.8%; the difference, however, was not significant (p = 0.588). Of 37 patients, 15 were alive and 22 deceased at the time of final analysis. The 5-year OS was 59.5% (68.8% per protocol). The primary endpoint of a 5-year LC of 70% was not met. This might be explained by the inclusion of recurrent disease and the high rate of G3 lesions and leiomyosarcoma, which have been shown to profit less from radiotherapy. Stratification by grading and histology should be considered for future studies.

Diagnostic accuracy of biopsy after neoadjuvant treatment for well-differentiated and dedifferentiated retroperitoneal liposarcoma

PurposeAccurate histopathological grading of percutaneous biopsies is essential to guide adequate management of patients with suspected retroperitoneal liposarcoma. In this regard, however, limited reliability has been described. Therefore, we conducted a retrospective study to assess the diagnostic accuracy in retroperitoneal soft tissue sarcomas and simultaneously investigate its impact on patients' survival. Materials and methodsReports of an interdisciplinary sarcoma tumor board between 2012 and 2022 were systematically screened for patients with well-differentiated (WDLPS) and dedifferentiated retroperitoneal liposarcoma (DDLPS). Histopathological grading on pre-operative biopsy was correlated with corresponding postoperative histology. Additionally, patients' survival outcomes were examined. All analyses were performed in two subgroups: patients with primary surgery and patients with neoadjuvant treatment. ResultsA total of 82 patients met our inclusion criteria. Diagnostic accuracy of patients who underwent upfront resection (n = 32) was significantly inferior to patients with neoadjuvant treatment (n = 50) (66% versus 97% for WDLPS, p < 0.001; 59% versus 97% for DDLPS, p < 0.001). For patients with primary surgery, histopathological grading on biopsy and surgery was concordant in only 47% of cases. Sensitivity for detecting WDLPS was higher than for DDLPS (70% versus 41%). Higher histopathological grading in surgical specimens correlated with worse survival outcomes (p = 0.01). ConclusionHistopathological grading of RPS may no longer be reliable after neoadjuvant treatment. The true accuracy of the percutaneous biopsy may need to be studied in patients who do not receive neoadjuvant treatment. Future biopsy strategies should aim to improve identification of DDLPS to inform patient management.

Efficacy and safety of anlotinib plus camrelizumab in treating retroperitoneal soft tissue sarcomas: a single-center retrospective cohort study.

Conventional chemotherapy has limited therapeutic effects in retroperitoneal soft tissue sarcomas (RSTs), while anlotinib emerged as a novel multi-target tyrosine kinase inhibitor (TKI) for sarcomas. TKIs in combination with immunotherapy have demonstrated clinical activity in a variety of solid tumors. This study retrospectively analyzed the efficacy and safety of anlotinib plus camrelizumab for the treatment of RSTs. Patients with RSTs who received anlotinib plus camrelizumab at Peking University Cancer Hospital Sarcoma Center were enrolled. Response assessment was conducted every 3 cycles of treatment according to response evaluation criteria in solid tumors version 1.1 (RECIST v1.1). Treatment-related adverse events (TRAEs) were evaluated by Common Terminology Criteria for Adverse Events (CTCAE) v5.0. Patients who had at least 1 response evaluation were analyzed. In all, 57 RSTs cases including 35 males and 22 females were analyzed, with a median age of 55 years. The pathological subtypes included 38 cases of L-sarcoma (liposarcoma and leiomyosarcoma), and 19 cases of non-L-sarcoma. Two patients (3.5%) had complete response (CR) and 13 patients (22.8%) had partial response (PR), with an objective response rate (ORR) of 26.3%. There were 31 (54.4%) and 11 (19.3%) patients with stable and progressive disease, respectively, with a disease control rate of 80.7%. Patients with non-L-sarcoma had a significantly better response rate than those with L-sarcoma (ORR: 52.6% vs. 13.2%; P=0.0031). After a median follow-up of 15.8 months, the median progression-free survival (PFS) was 9.1 months, with 3- and 6-month PFS rates of 83.6% and 60.8%, respectively. Patients with non-L-sarcoma had a significantly longer median PFS than did those with L-sarcoma (median PFS: 11.1 vs. 6.3 months; P=0.0256). TRAEs occurred in 28 (49.1%) patients, and 13 (22.8%) patients had grade 3-4 TRAEs. Hypertension (24.6%), hypothyroidism (19.3%), and palmar-plantar erythrodysesthesia syndrome (12.3%) were the most common TRAEs. The combination of anlotinib and camrelizumab demonstrated possible therapeutic efficacy and safety in the treatment of RSTs, especially for non-L-sarcomas.

PSAT023 Not Every Pain Is a Gain! A Rare Case of Adrenal Leiomyosarcoma.

Abstract Introduction Adrenal leiomyosarcoma (AL) is a rare malignant tumor, representing only 0.1% to 0.2% of all retroperitoneal soft tissue sarcomas in adults (1). A young male's acute abdominal and back pain led to an unusual diagnosis of AL. Case Presentation A 38-year-old male patient with no past medical history presented with a history of right sided abdominal pain of several months duration radiating to the back and significant weight loss. His vital signs were stable; however, he appeared mildly distressed and had tenderness on deep palpation in the right mid-upper quadrant. An abdominal sonogram showed a hypoechoic mass between the liver and the right kidney with no evidence of acute cholecystitis. A CT scan of the abdomen with IV contrast showed a lobulated mass invading the right adrenal gland, measuring 5.4×4.3×5.1 cm, with a post-contrast density measurement of 30 Hounsfield units. Laboratory tests showed plasma renin of 1.8 (upper limit of normal ULN 4.3 ng/ml/h), aldosterone of 8.6 (ULN 21 ng/dl), plasma metanephrine of &amp;lt;0.2 (ULN 0.50 nmol/l), and plasma normetanephrine of 0.49 (ULN 0.90 nmol/l). Additionally, his cortisol level after dexamethasone suppression was 0.9 (ULN 22.4 ug/dl). He underwent a right-sided laparoscopic adrenalectomy. The histopathological testing returned as a high-grade undifferentiated malignant neoplasm consistent with leiomyosarcoma. The IHC stains showed positive staining for SMA, CD10, and GATA3. He underwent whole-body PET/CT that showed multiple hypermetabolic abnormalities, including the right adrenalectomy bed, with a possible tumor invading the right upper renal pole. Systemic chemotherapy with doxorubicin and dacarbazine was initiated. Foundation panel testing showed NF1 loss on exons 2-3, CDKN2A/B CDKN2A rearrangement on exon 2, and TP53 loss on exons 1-4. He has received two rounds of chemotherapy, with no evidence of disease progression. Discussion Adrenal leiomyosarcoma usually originates from the smooth muscle cells of the adrenal or adjacent vascular structures. The tumor is asymptomatic until it enlarges and compresses the surrounding structures. Currently, there are about 50 reported valid cases (2) with no reports of NF-1 exon loss to our knowledge. The primary treatment is radical surgery with or without adjuvant chemotherapy and radiotherapy. Foundation panel testing showing NF-1 and TP53 exon loss may guide future targeted therapy. References 1-Fatema Jabarkhel, Henri Puttonen, Lina Hansson, Andreas Muth, Oskar Ragnarsson, Primary Adrenal Leiomyosarcoma: Clinical, Radiological, and Histopathological Characteristics, Journal of the Endocrine Society, Volume 4, Issue 6, June 2020. 2-Bahador Oshidari, Amir Zamani, Hooman Bahrami-Motlagh, Elena Jamali, Setareh Mahmoodi, Manoochehr Ebrahimian, Primary leiomyosarcoma of the adrenal; a case report, International Journal of Surgery Case Reports, Volume 90, 2022, 106707. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

Landmark Series: A Review of Landmark Studies in the Treatment of Primary Localized Retroperitoneal Sarcoma.

Primary localized retroperitoneal soft tissue sarcomas (RPS) have shorter survival than other soft tissue sarcoma sites owing to higher local recurrence rates associated with histologic types most commonly found in this location, large tumor size at diagnosis (median 20cm), and anatomical constraints of surgery in the retroperitoneum. The only curative treatment for RPS has traditionally been complete macroscopic en bloc resection with adjacent structures that cannot be surgically separated from the tumor. Compartmental resection, incorporating adjacent organs and soft tissues en bloc, even without overt infiltration at the time of surgery, performed in sarcoma referral centers may reduce local recurrence rates. Preoperative radiotherapy has not been shown to reduce early 3-year local recurrences in a phase III, international, randomized, controlled trial (STRASS). Longer follow-up is needed to determine whether well-differentiated and low-grade dedifferentiated liposarcoma prone to late local recurrences may benefit. Currently, there is no level 1 evidence to support the use of perioperative systemic therapy. Observational studies suggest that patients with high-grade histologies and borderline resectable RPS may benefit. A phase III, international, randomized, controlled trial (STRASS2) is currently evaluating a histology-tailored chemotherapy regimen for patients with leiomyosarcoma and dedifferentiated liposarcoma at high risk of distant metastatic recurrence. Novel biomarkers can help determine prognosis and more accurately predict response to treatment, but more research is needed to translate these discoveries into therapeutic benefits. Refined molecular data for histological types will allow personalized surgery, radiotherapy, and systemic therapy with lower toxicity and improved survival in the future.

Updates in Pathology for Retroperitoneal Soft Tissue Sarcoma.

Retroperitoneal tumors are extremely rare. More than 70% of primary retroperitoneal soft tissue tumors are malignant. The most common sarcomas in the retroperitoneum include liposarcomas and leiomyosarcoma, however other sarcomas, along with benign mesenchymal tumors, can occur. Sarcomas are a heterogenous group of tumors with overlapping microscopic features, posing a diagnostic challenge for the pathologist. Correct tumor classification has become important for prognostication and the evolving targeted therapies for sarcoma subtypes. In this review, the pathology of retroperitoneal soft tissue sarcomas is discussed, which is important to the surgical oncologist. In addition, less common sarcomas and benign mesenchymal tumors of the retroperitoneum, which may mimic sarcoma clinically and pathologically, are also discussed.

The role of standard and novel radiotherapy approaches in management of retroperitoneal sarcomas

Primary non-metastatic retroperitoneal soft tissue sarcoma patients can be cured by radical surgery. However there remains a risk for patients to develop a local recurrence. To minimize this risk, patients with low grade liposarcomas might benefit from preoperative radiotherapy. This review summarizes all issues that should be considered for the irradiation of patients with retroperitoneal soft tissue sarcoma.

Closing the Distance Between Access and Expertise in Patients with Bone Sarcomas: Is There a Feasible Path Forward?: Commentary on an article by Tomohiro Fujiwara, MD, PhD, et al.: "Geographic Access to High-Volume Care Providers and Survival in Patients with Bone Sarcomas. Nationwide Patterns in the United States".

Commentary It is the dreaded news that we as oncology providers occasionally need to deliver to patients: “You have cancer.” Where should they turn for the best care? Is a local hospital enough, or is it beneficial to travel a farther distance to receive care at a more specialized institution? If that cancer happens to be a bone sarcoma, Fujiwara et al. have done a commendable job in providing further insight into this question in their current article. In recent years, an increasing amount of literature has been published with regard to improved outcomes at high-volume centers for many types of cancer, including non-orthopaedic tumors such as colorectal cancer1. As it relates to musculoskeletal malignancies, Abarca et al.2 showed, for extremity soft-tissue sarcomas, and Schmitz et al.3 showed, for retroperitoneal soft-tissue sarcomas, that high-volume facilities had a better overall survival rate and a lower rate of positive surgical margins when compared with lower-volume centers. Intuitively, I think, for those of us who treat bone sarcomas, it is understood that you need a multidisciplinary team in place with an abundance of experience and adherence to nationally accepted treatment guidelines. From a surgical standpoint, improved outcomes seem to correlate with repetition of treatment. However, what may not seem intuitive is that, when it comes to a rare type of tumor such as a bone sarcoma (only roughly 3,900 new cases will be diagnosed in the United States this year), the critical volume of experience needed to optimize outcomes is likely not available at every institution and may not even be available within every state. Given the limitation in new cases each year, centralized care for patients with bone sarcoma, or any other unique cancer, seems like an enticing system to help to improve survival. If a patient lives close to a high-volume center, then this treatment route is a no-brainer. However, for patients who may live farther away, choosing to travel a long distance to receive care at a high-volume center may mean lengthy time away from family and other support systems. If these individuals choose to not travel to a high-volume center, does this necessarily mean that they are negatively impacting their ability to be alive 5 years or even 10 years from now? I am not sure that we have a fully transparent answer to that question yet. As shown in the current article and previously reported by Malik et al.4, the overall survival for adult patients with bone sarcoma was not necessarily impacted by how far they had to travel to receive care but rather seeking care at an institution with extensive experience in treating this malignancy. In the virtual world in which we now live and with the increase in community-based hospital partnerships with high-volume National Cancer Institute (NCI) institutions, a patient now expects to receive the same level of expert care closer to home. What would be interesting to know (and is certainly beyond the scope of this article) is whether improved survival holds up at lower-volume centers that partner with higher-volume centers and adhere to nationally accepted treatment guidelines. I think that the landscape of musculoskeletal oncology would look quite different if we were to move toward a more centralized care pattern for patients with bone sarcoma. In his commentary article discussing high-volume centers compared with low-volume centers as they relate to pancreatic cancer, Carr5 brought up many relevant points that I think merit consideration for bone sarcomas. As Carr stated, it is simply not practical for patients with cancer, even rare or unique cancers, to be treated at only a handful of high-volume institutions. In addition, those patients who have complex reconstructive surgical procedures at places far away from where they live may require follow-up or operative care locally for complications that arise. A patient may travel once for a surgical procedure, but that willingness may wane over time for follow-up visits, leaving the onus on more local, less-experienced institutions to complete their course of care. Another point to consider is the need for increased oncology specialists at these high-volume centers to meet the potential increase in patient demand. In the end, we all want the best care for the patients whom we treat. The reality is that not every patient will travel, despite what the data show. The challenge then becomes how we can disseminate knowledge and experience to help to level the playing field so that adult patients can receive top-notch care for bone sarcoma closer to home. I am hopeful that future studies will help in clarifying this.

Radiomic Features From Diffusion-Weighted MRI of Retroperitoneal Soft-Tissue Sarcomas Are Repeatable and Exhibit Change After Radiotherapy.

BackgroundSize-based assessments are inaccurate indicators of tumor response in soft-tissue sarcoma (STS), motivating the requirement for new response imaging biomarkers for this rare and heterogeneous disease. In this study, we assess the test–retest repeatability of radiomic features from MR diffusion-weighted imaging (DWI) and derived maps of apparent diffusion coefficient (ADC) in retroperitoneal STS and compare baseline repeatability with changes in radiomic features following radiotherapy (RT).Materials and MethodsThirty patients with retroperitoneal STS received an MR examination prior to treatment, of whom 23/30 were investigated in our repeatability analysis having received repeat baseline examinations and 14/30 patients were investigated in our post-treatment analysis having received an MR examination after completing pre-operative RT. One hundred and seven radiomic features were extracted from the full manually delineated tumor region using PyRadiomics. Test–retest repeatability was assessed using an intraclass correlation coefficient (baseline ICC), and post-radiotherapy variance analysis (post-RT-IMS) was used to compare the change in radiomic feature value to baseline repeatability.ResultsFor the ADC maps and DWI images, 101 and 102 features demonstrated good baseline repeatability (baseline ICC > 0.85), respectively. Forty-three and 2 features demonstrated both good baseline repeatability and a high post-RT-IMS (>0.85), respectively. Pearson correlation between the baseline ICC and post-RT-IMS was weak (0.432 and 0.133, respectively).ConclusionsThe ADC-based radiomic analysis shows better test–retest repeatability compared with features derived from DWI images in STS, and some of these features are sensitive to post-treatment change. However, good repeatability at baseline does not imply sensitivity to post-treatment change.

Clinical Outcome of Patients with Pelvic and Retroperitoneal Bone and Soft Tissue Sarcoma: A Retrospective Multicenter Study in Japan.

Simple SummaryWe aimed to clarify the clinical outcomes of patients with pelvic and retroperitoneal bone and soft tissue sarcoma. The 3-year overall survival (OS), local control (LC) rate, and progression-free survival (PFS) were 71.7%, 79.1%, and 48.6%, respectively. The most influential poor prognostic factor for OS was distant metastasis, and for PFS, this was higher age (≥60 years). Larger primary tumor size (≥10 cm) was the only poor prognostic factor for LC. In the histological analysis, osteosarcoma showed significantly worse OS and PFS than other sarcomas in the pelvis and retroperitoneum.This study aimed to retrospectively analyze the clinical outcomes of patients with pelvic and retroperitoneal bone and soft tissue sarcoma (BSTS). Overall, 187 patients with BSTS in the pelvis and retroperitoneal region treated at 19 specialized sarcoma centers in Japan were included. The prognostic factors related to overall survival (OS), local control (LC), and progression-free survival (PFS) were evaluated. The 3-year OS and LC rates in the 187 patients were 71.7% and 79.1%, respectively. The 3-year PFS in 166 patients without any distant metastases at the time of primary tumor diagnosis was 48.6%. Osteosarcoma showed significantly worse OS and PFS than other sarcomas of the pelvis and retroperitoneum. In the univariate analyses, larger primary tumor size, soft tissue tumor, distant metastasis at the time of primary tumor diagnosis, P2 location, chemotherapy, and osteosarcoma were poor prognostic factors correlated with OS. Larger primary tumor size, higher age, soft tissue tumor, chemotherapy, and osteosarcoma were poor prognostic factors correlated with PFS in patients without any metastasis at the initial presentation. Larger primary tumor size was the only poor prognostic factor correlation with LC. This study has clarified the epidemiology and prognosis of patients with pelvic and retroperitoneal BSTS in Japan.

Intraabdominal and retroperitoneal soft-tissue sarcomas – Surgical treatment and outcomes

BackgroundIntraabdominal and retroperitoneal sarcomas (IaRS) are malignant connective tissue tumors. Surgical resection is often the only curative treatment. The primary objective was to report the mid-term outcomes following contemporary treatment protocols and identify prognostic factors. MethodsA retrospective review of consecutive patients (n = 107) with IaRS treated at single center from 2013 until 2018 was conducted. Histological diagnosis, tumor grade, perioperative complications, mortality, and long-time survival were registered and retrieved from patient records. Primary and recurrent tumors were analyzed separately. ResultsA total of 107 patients were identified. Median follow-up time was 3.5 years. Thirty-day mortality was 3.4% and 90-day mortality was 5.6% for all tumors. The major complication rate was 18%. The 5-year estimated survival for primary and recurrent tumors was 55.4% and 48.4%, respectively. Multifocal disease was evident in 32% of the patient cohort, and 58% of patients in the recurrent group. Multivariate analysis for survival revealed a hazard ratio (HR) of 3.1 (95% CI 1.68–8.41) for multifocality, HR 2.9 (95% CI 1.28–6.98) for Clavien-Dindo grade, HR 2.3 (95% CI 1.21–4.31) for tumor grades 2 or 3, and HR 1.002 (95% CI 1.001–1.004) for surgical margins. ConclusionsOur study found overall acceptable morbidity and mortality, and identified prognostic markers for overall survival. Recurrent tumors were not associated with worse survival. Multifocality is associated with a worse overall survival. The prognostic factors identified were; tumor grade, multifocality, intralesional margins and postoperative complications.