Preoperative chemo-radiation therapy for localised retroperitoneal sarcoma: A phase I–II study from the Italian Sarcoma Group

Transmediastinal primary pulmonary liposarcoma: Case report and review of management strategies

Soft tissue sarcomas account for less than 1% of new cancer diagnoses, approximately one in five of which are liposarcomas. These tumors typically arise in the deep tissues of the proximal extremity or retroperitoneum, with just under 3% presenting as primary intrathoracic neoplasms. We present an exceedingly rare and particularly unique presentation of primary lung liposarcoma which traversed the mediastinum into the contralateral hemithorax. This report highlights the primary characteristics of the disease and underscores the importance of a multidisciplinary approach to its successful treatment.

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.

How to treat liposarcomas located in retroperitoneum

Almost half of retroperitoneal (RP) sarcomas are liposarcomas (LPS). The large majority of RP LPS are either well-differentiated LPS (WDLPS) or dedifferentiated LPS (DDLPS), these latter further classified according to grading in G2 and G3 DDLPS. Surgery is the only potentially curative treatment to achieve local control and possibly cure in primary localized disease. Over the last decade, a better delineation of the different histology-specific patterns of failure and the development of nomograms predictors of outcome has led to a better management of these rare tumors, with a special focus on non-surgical treatments. Available evidences - although far from exhaustive - show that radiation therapy might have a role, if any, as neoadjuvant treatment in locally aggressive histologies (i.e. WDLPS and G2 DDLPS), while it does not seem beneficial for histologies with a higher metastatic risk (i.e. G3 DDLPS and leiomyosarcoma). Neoadjuvant chemotherapy, instead, can be considered to reduce the risk of distant metastasis while waiting for the results of an ongoing RCT (STRASS-2) evaluating its effect in these tumors. However, given the rarity of these diseases and the subsequent lack of strong evidences to guide treatment, outcome improvement in these patients remains a challenge. Patients' referral to a sarcoma center where a dedicated specialized multidisciplinary team tailor optimal treatment on a case-by-case basis is crucial to ensure these patients the best outcome. Refining available nomograms - e.g including molecular variables - and identifying predictors of response/toxicity to chemotherapy and immunotherapy might be significantly helpful in tailoring treatments to the patient's characteristics. Also, new systemic agents are eagerly awaited for improving the management further.

Midterm Results of High-Dose-Rate Intraoperative Brachytherapy in the Treatment of Soft Tissue Sarcomas

INTRODUCTION

According to the literature only sparse data are available on the use of high-dose-rate intraoperative brachytherapy (IOHDR-BT) as a boost to external-beam irradiation (EBRT) in combination with a wide resection in patients with high-grade soft tissue sarcomas (STS).

MATERIALS AND METHODS

Applying a retrospective study design, we investigated all patients who between 2010 and 2016 underwent marginal resection of a high-grade STS and intraoperative radiotherapy, followed by EBRT. We included only patients with a traceable follow-up time of at least two years. Of 89 patients, 35 met our inclusion criteria and showed an average follow-up of four years.

RESULTS

We found an overall 2-year local control rate of 94.3%. The local recurrence rate for R0 resections was 6%, whereas recurrences occurred in 13% of R1 resections and in 100% of R2 resections. One affected patient received only intraoperative radiotherapy. The recurrence rate by tumour entity was 36% for LPS, 11% for myxofibrosarcoma and 17% for undifferentiated pleomorphic sarcoma.

CONCLUSION

The treatment regimen consisting of limb-preserving surgery, IORT and pre- or postoperative radiotherapy consistently shows excellent local control rates.

IOeRT in retroperitoneal sarcoma: Towards more organ preservation with comparable oncological outcomes

BACKGROUND

Retroperitoneal sarcomas (RPS) present a surgical challenge with high rates of local recurrence (LR). We investigated the role of intraoperative electron radiotherapy (IOeRT) in reducing LR after surgical resection of RPS.

METHODS

A retrospective analysis of all patients who underwent surgical resection for RPS between 2014 and 2021 at a tertiary academic referral center (n = 172). Patients included underwent surgical resection of their RPS and received IOeRT (n = 36) and were compared by case control matching to patients with similar tumor characteristics (recurrence status and tumor grade) that did not receive IOeRT (n = 36).

RESULTS

The median length of hospitalization was 8 days (range, 4-34) in the IOeRT group and 10 days (range, 2-42) in the non-IOeRT group (p = 0.25). The mean operating room (OR) time was 4h (±1.3) and 4h (±1.9) in the IOeRT and non-IOeRT groups respectively, (p = 0.37). Complete resection with R0 margins was achieved in 30 patients (83.3%) and 24 patients (66.6%) in the IOeRT and non-IOeRT groups, respectively (p = 0.1). R1 resection was achieved in 6 patients (16.6%) and 12 patients (33.3%) respectively, (p = 0.1). The resected organ weighted score was significantly different between the groups; score 0 observed in 19 (52.7%) patients in the IOeRT group and 3 (8.3%) in the non-IOeRT group (p < 0.001), score 1 observed in 7 (19.4%) in the IOeRT group and 17 (47.2%) in the non-IOeRT group (p = 0.012). The rate of severe complications (CD score>3) did not differ between the groups, 5 (13.8%) patients in the IOeRT group and 9 (25%) patients in the non-IOeRT group (p = 0.23). No radiation associated complications were noted. The 2-year local recurrence free survival (LRFS) was 75.9% in the IOeRT group and 60.3% in the non-IOeRT group (p = 0.4). The 2-year IOeRT field recurrent free survival (IRFS) was 88.4% in the IOeRT group and 60.3% in the non-IOeRT group (p = 0.04).

CONCLUSIONS

The use of IOeRT did not increase the rate of surgical complications and was associated with superior local control in the radiation field, improved organ preservation without an impact on overall survival.

Pleomorphic Liposarcoma Revisited

Pleomorphic liposarcoma (PLPS) is the rarest and more aggressive subtype of liposarcomas, accounting for 10% of all liposarcomas. The diagnosis should be considered after the detection of multivacuolated pleomorphic lipoblasts in biopsy specimens. Wide-margin resection is the treatment of choice. Complementary treatment options, such as radiation therapy and chemotherapy, are debatable in terms of their contribution to curing patients with PLPS. This article reviews the clinical, histopathological, and molecular characteristics of PLPS and discusses the latest trends in the management, therapeutic strategies, and novel investigations of the subject. [Orthopedics. 2023;46(2):e72-e80.].

Feasibility of Preoperative Dose-Painting Intensity Modulated Radiation Therapy (IMRT) for Borderline-Resectable Primary Retroperitoneal Sarcoma

PURPOSE

The role of radiation therapy (RT) in resectable retroperitoneal sarcoma (RPS) remains controversial; however, preoperative RT may play an important role in borderline-resectable (at risk of R2 resection) disease. We evaluated the outcome of such patients treated with preoperative dose-painting IMRT followed by planned resection.

METHODS

Between January 2001 and December 2017, 30 patients with borderline-resectable primary nonmetastatic RPS (after multidisciplinary review) received preoperative dose-painting IMRT in this retrospective cohort study.

RESULTS

Median follow-up for all patients was 32 months. Median dose to the whole tumor/high-risk margin was 50.4 Gy/60.2 Gy. Sixteen patients were female, 24 were >50 years. Median tumor size was 9.2 cm. After RT, 6 did not have surgery. Of the 24 who were explored, 20 underwent complete gross resection. During RT, 7 of 30 patients developed acute grade 2+ toxicities: 5 fatigue, 1 nausea and vomiting, and 1 cystitis. RT was completed in 29 of 30 patients. Postoperatively, 12 of 20 patients developed grade 2+ complications: 2 gastropathy, 5 intraabdominal collections requiring drainage, 1 retroperitoneal bleed, and 3 delayed wound healing. Late grade 2+ toxicity was observed in 3 of 20 patients: 1 lymphedema with recurrent cellulitis, 1 chronic diarrhea, 1 gastrointestinal bleeding from anastomosis requiring transfusions, and 2 renal insufficiency. In those who underwent complete gross resection (n = 20, median follow-up 47 months), the 5-year local control was 57%, and overall survival was 46%.

DISCUSSION

Preoperative dose-painting IMRT given to borderline-resectable RPS rendered 67% of patients resectable, provided a 5-year local control rate of 57%, which is similar to those with resectable disease, and had an acceptable morbidity profile.

Relevant Trials Update in Sarcomas and Gastrointestinal Stromal Tumors: What Surgeons Should Know

In the past few years, the sarcoma community has successfully completed several trials in patients with soft tissue sarcoma (STS) or gastrointestinal stromal tumor (GIST). The current review summarizes recently reported relevant trials or trial updates investigating radiotherapy, chemotherapy, and targeted therapy in patients with localized extremity or superficial trunk STS, retroperitoneal sarcoma, and GIST.

First and further-line multidisciplinary treatment of retroperitoneal sarcomas

PURPOSE OF REVIEW

To review current knowledge and recent advances in retroperitoneal sarcoma management.

RECENT FINDINGS

Surgery, radiotherapy, and medical treatments of retroperitoneal sarcomas should take into account the peculiarities of each histotype and the unique anatomical site. Surgery remains the mainstay of treatment and the only chance of cure for these diseases. In low-grade retroperitoneal sarcomas, like well differentiated liposarcoma, where the leading cause of death is dominated by local rather than distant relapses, treatment of the primary tumor encompasses extended surgery with multiorgan resection and evaluation of preoperative radiotherapy. Conversely, surgery is usually more conservative and without radiotherapy in those retroperitoneal sarcomas, such as leiomyosarcoma, characterized by a high risk of metastatic spread that prompted also the evaluation of neoadjuvant, histotype-driven chemotherapy. Surgery might have a role also for relapsed disease, despite long-term disease control probability declines at each recurrence. In advanced stages, anthracyclines still retain a key role and all medical treatment strategies should follow the specific chemosensitivity of each histotype to improve patient's outcomes.

SUMMARY

The rarity and heterogeneity in biological behavior and clinical presentation of retroperitoneal sarcomas deserves a multidisciplinary and histotype-driven treatment at all stages of the disease to be performed in highly specialized centers.

Feasibility and Safety of Intraoperative Radiotherapy with Low Energy X-ray Photon Therapy for Recurrent Gynecological Cancer: A Case Series

Objectives: To evaluate the feasibility and safety of low energy X-ray photon intraoperative radiotherapy (IORT) as an adjuvant therapy for recurrent gynecological cancer.Methods: Medical records of all recurrence gynecological cancer patients who underwent IORT were reviewed. Results: Between January 2018 and December 2021, five women (including cervical cancer (n = 2), endometrial cancer (n = 2), and uterine leiomyosarcoma (n = 1)), who underwent IORT and surgical resection for recurrent gynecologic cancer were reviewed. A median dose of 15.62 Gy (range, 12 to 20 Gy) was used for IORT. Repeated IORT and surgical resection was performed in two women. Three women experienced local recurrence, and three women died during follow-up. The 1-year local control rate was 60%. The 2-year overall survival rate was 30%. There was no Clavien–Dindo classification grade III–V complication. Conclusion: IORT using low energy X-ray photon therapy seems to be feasible and safe as an adjuvant therapy in women who underwent salvage surgery for recurrent gynecologic cancer. However, large-scale prospective studies are needed to confirm our findings and evaluate its efficacy.

The evolution of adjuvant/neoadjuvant trials for resectable localized sarcoma

Soft-tissue sarcomas are rare tumors arising from mesenchymal tissues. As a heterogeneous group comprising more than 50 types, the development of clinical trials remains challenging. Decision-making for neoadjuvant or adjuvant chemotherapy and radiation therapy is based on the available evidence of contemporary trials and multidisciplinary clinical judgment.

Comparison of preoperative chemoradiation with radiation or chemotherapy alone in patients with non-metastatic, resectable retroperitoneal sarcoma

Aim:

Optimal preoperative therapy regimen in the treatment of resectable retroperitoneal sarcoma (RPS) remains unclear. This study compares the impact of preoperative radiation, chemoradiation and chemotherapy on overall survival (OS) in RPS patients.

Materials and Methods:

The National Cancer Database (NCDB) was queried for patients with non-metastatic, resectable RPS (2006–15). The primary endpoint was OS, evaluated by Kaplan–Meier method, log-rank test, Cox multivariable analysis and propensity score matching.

Results:

A total of 1,253 patients met the inclusion criteria, with 210 patients (17%) receiving chemoradiation, 850 patients (68%) receiving radiation and 193 patients (15%) receiving chemotherapy. On Cox multivariable analysis, when compared to preoperative chemoradiation, preoperative radiation was not associated with improved OS (hazards ratio [HR] 0·98, 95% CI 0·76–1·25, p = 0·84), while preoperative chemotherapy was associated with worse OS (HR 1·64, 95% CI 1·24–2·18, p < 0·001). Similar findings were observed in 199 and 128 matched pairs for preoperative radiation and chemotherapy, respectively, when compared to preoperative chemoradiation.

Findings:

Our study suggested an OS benefit in using preoperative chemoradiation compared to chemotherapy alone, but OS outcomes were comparable between preoperative chemoradiation and radiation alone.

Neoadjuvant concurrent chemoradiotherapy with and without hyperthermia in retroperitoneal sarcomas: feasibility, efficacy, toxicity, and long-term outcome

Purpose

Retroperitoneal (RPS) sarcomas are associated with poor local and abdominal tumor control. However, the benefit of preoperative radio- or chemotherapy alone for these entities is currently unclear. Moreover, as intermediate- and high-grade sarcomas have a tendency toward early metastasis, exploration of neoadjuvant strategies is of high importance. This analysis reports the results of our 20-year single-institution experience with preoperative neoadjuvant concurrent chemoradiation.

Methods

From 2000–2019, 27 patients with intermediate- or high-grade RPS (12 dedifferentiated liposarcoma, 10 leiomyosarcoma, 5 others) were treated with radiotherapy (median dose: 50.4 Gy; range 45–75 Gy) and two cycles of chemotherapy (doxorubicin 50 mg/m² BSA/d3 q28 and ifosfamide 1.5 g/m² BSA/d1‑5 q28) in neoadjuvant intent. Chemotherapy consisted of doxorubicin alone in two cases and ifosfamide alone in one case. Fifteen patients (56%) additionally received deep regional hyperthermia.

Results

The median follow-up time was 53 months (±56.7 months). 92% of patients received two cycles of chemotherapy as planned and 92% underwent surgery. At 5 and 10 years, abdominal-recurrence-free survival was 74.6% (±10.1%) and 66.3% (±11.9%), distant metastasis-free survival was 67.2% (±9.7%) and 59.7% (±11.1%), and overall survival was 60.3% (±10.5%) and 60.3% (±10.5%), respectively. CTC grade III and IV toxicities were leukocytopenia (85%), thrombocytopenia (33%), and anemia (11%). There were no treatment-related deaths.

Conclusion

Neoadjuvant chemoradiotherapy with and without hyperthermia for retroperitoneal sarcomas is feasible and provided high local control of intermediate- and high-grade sarcoma.

Long-Term Follow-Up of Patients Receiving Neoadjuvant Treatment Modalties for Soft Tissue Sarcomas of the Extremities

BACKGROUND

Neoadjuvant treatment modalities in soft tissue sarcoma (STS) of the extremities have become more popular in recent years, but because of the rarity and heterogeneity of STS, there are yet few studies on the long-term impact of neoadjuvant treatment modalities, especially in terms of neoadjuvant radiochemotherapy.

METHODS

The study enrolled 136 patients with primary STS of the extremities who underwent surgery with curative intent or neoadjuvant therapy, followed by surgery in a 15-year period. Neoadjuvant treatment consisted of radiotherapy (RT) with 60 Gy and in most cases simultaneous chemotherapy (CTx) with ifosfamide (1.5 g/m²/d, d1-5, q28) and doxorubicine (50 mg/m²/d, d3, q28). We investigated the clinical, (post)-operative and histopathological data and the oncological follow-up as well. The median follow-up period was 82 months (range 6-202).

RESULTS

A total of 136 patients (M:F = 73:63) with a mean age of 62 years (range; 21-93) was observed. Seventy-four patients (54.4%) received neoadjuvant therapy (NT), 62 patients (45.6%) received primary surgery (PS). When receiving NT, patients with high-risk STS had a lower risk to develop distant metastasis (p = 0.025). Age, histological type, tumor size and surgical margins (R0 vs. R1) had no influence on any survival rates. There was an association between NT and the occurrence of postoperative complications (p = 0.001). The 5-year local recurrence free survival (LRFS), metastasis free survival (MFS), disease free survival (DFS) and overall survival (OS) rate of the whole cohort was 89.9%, 77.0%, 70.6% and 72.6%; whereas the 5-year LRFS, MFS, DFS and OS rate was 90.5%, 67.2%, 64.1% and 62.8% for the NT group and 89.5%, 88.3%. 78.4% and 83.8% for the PS group.

CONCLUSIONS

Multimodal treatment strategies in patients with STS of extremities lead to excellent oncological outcomes. Patients with high-risk STS had a significantly better MFS when receiving NT than patients with low-risk STS. NT was associated with a higher probability of postoperative but well-manageable complications.

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

Simple Summary

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

Abstract

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

Role of Radiation Therapy for Newly Diagnosed Retroperitoneal Sarcoma

OPINION STATEMENT

Soft tissue sarcomas (STS) are rare, aggressive, and heterogenous tumors, comprising approximately 1% of adult cancers with over 50 different subtypes. The mainstay of treatment for retroperitoneal sarcomas (RPS) includes surgical resection. The addition of radiation therapy (RT), either preoperatively or postoperatively, has been used to potentially decrease the risk of local recurrence. The recently published results from STRASS (EORTC-STBSG 62092-22092), which randomized patients to receive or not receive preoperative radiation, indicate no abdominal recurrence-free survival benefit (primary endpoint) nor overall survival benefit to date from the addition of preoperative RT prior to surgical resection in patients with RPS. Keeping in mind caveats of subgroup analyses, the data show a significant reduction in local recurrence with radiation therapy in resected patients and non-significant trends toward improved abdominal recurrence-free survival in all patients and improved local control and abdominal recurrence-free survival in patients with liposarcoma and low-grade sarcoma. Given the high rate of local failure with surgery alone, it is possible that higher RT dose and/or selective RT dose painting may improve outcomes. Prior to treatment, the authors encourage multidisciplinary review and discussion of management options at a sarcoma center for patients with RPS. Selective use of RT may be considered for patients at high risk of local recurrence.

Management of Primary Retroperitoneal Sarcoma (RPS) in the Adult: An Updated Consensus Approach from the Transatlantic Australasian RPS Working Group

BACKGROUND

Retroperitoneal soft tissue sarcomas comprise a heterogeneous group of rare tumors of mesenchymal origin that include several well-defined histologic subtypes. In 2015, the Transatlantic Australasian RPS Working Group (TARPSWG) published consensus recommendations for the best management of primary retroperitoneal sarcoma (RPS). Since then, through international collaboration, new evidence and knowledge have been generated, creating the need for an updated consensus document.

METHODS

The primary aim of this study was to critically evaluate the current evidence and develop an up-to-date consensus document on the approach to these difficult tumors. The resulting document applies to primary RPS that is non-visceral in origin, with exclusion criteria as previously described. The relevant literature was evaluated and an international group of experts consulted to formulate consensus statements regarding the best management of primary RPS. A level of evidence and grade of recommendation were attributed to each new/updated recommendation.

RESULTS

Management of primary RPS was considered from diagnosis to follow-up. This rare and complex malignancy is best managed by an experienced multidisciplinary team in a specialized referral center. The best chance of cure is at the time of primary presentation, and an individualized management plan should be made based on the 29 consensus statements included in this article, which were agreed upon by all of the authors. Whenever possible, patients should be enrolled in prospective trials and studies.

CONCLUSIONS

Ongoing international collaboration is critical to expand upon current knowledge and further improve outcomes of patients with RPS. In addition, prospective data collection and participation in multi-institution trials are strongly encouraged.

Definitive Radiotherapy in the Management of Non-Resectable or Residual Retroperitoneal Sarcomas: Institutional Cohort Analysis and Systematic Review

BACKGROUND

There is currently no consensus on optimal management of patients with primary or recurrent non-resectable/residual retroperitoneal sarcomas (RPS). The objective of this study was to document the outcomes of patients with primary or recurrent non-resectable/residual RPS treated in our center with definitive radiotherapy (RT) and to perform a systematic review on the topic.

METHODS

A retrospective analysis of consecutive RPS patients treated in our center between 2000 and 2019 was performed. All consecutive patients who underwent definitive conformal RT with image guidance for primary or recurrent non-resectable or macroscopically residual RPS were included. Additionally, a systematic review compliant with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses was performed.

RESULTS

The study enrolled 14 patients who met the aforementioned criteria. Data on clinicopathological characteristics, RT and response to treatment were assessed. RT allowed achieving prolonged local control of the disease, i.e. no local progression of the disease for more than 12 months after RT in 10 patients. Local control lasted more than 24 months in 6 cases, with minimal or no toxicity. A systemic review of 11 studies revealed concordance of our results with previous reports of primary or recurrent non-resectable/residual RPS.

CONCLUSIONS

RT provided satisfactory local disease control with acceptable treatment tolerance in patients with primary or recurrent non-resectable/residual RPS and represents a valuable treatment modality in the selected group of patients. Additional RT modalities i.e. BT, particle therapy, MRI-guided RT, or GRID/Lattice RT may be introduced to improve local control and further minimize toxicity.

Perioperative strategy and outcome in giant retroperitoneal dedifferentiated liposarcoma-results of a retrospective cohort study

Background and objectives

Retroperitoneal liposarcoma (RPLS) are common soft tissue sarcomas of adulthood. The aim of this study is to show resectability of even giant liposarcomas and to identify factors associated with recurrence and survival in primary retroperitoneal liposarcomas.

Methods

We retrospectively reviewed the records of patients with retroperitoneal liposarcoma. Seventy-seven patients met inclusion criteria. Out of these 10 patients with primary giant, dedifferentiated retroperitoneal liposarcomas were operated with en bloc compartment resection with intention of radical resection. Treatment consisted of neoadjuvant radiochemotherapy and surgical resection or surgical resection.

Results

In 6 patients, neoadjuvant radiochemotherapy was performed; 3 patients were treated with surgical resection alone and 1 patient received adjuvant chemotherapy. The median diameter of tumor size was 360 mm (300 to 440 mm). Operative outcome showed complete resection in all 10 patients. Local tumor free survival was in median 19 month. Tumor recurrence was seen in 3 of 4 patients (75%) without neoadjuvant radiochemotherapy, and in 2 of 6 patients (33%) after neoadjuvant radiochemotherapy in 2 years follow-up.

Conclusion

Even in case of giant retroperitoneal liposarcoma, complete resection is possible and remains the principal treatment. The rate of recurrence was improved in patients with neoadjuvant radiochemotherapy.

Radiation Therapy in Adult Soft Tissue Sarcoma-Current Knowledge and Future Directions: A Review and Expert Opinion

Simple Summary

Radiation therapy (RT) is an integral part of the treatment of adult soft-tissue sarcomas (STS). Although mainly used as perioperative therapy to increase local control in resectable STS with high risk features, it also plays an increasing role in the treatment of non-resectable primary tumors, oligometastatic situations, or for palliation. This review summarizes the current evidence for RT in adult STS including typical indications, outcomes, side effects, dose and fractionation regimens, and target volume definitions based on tumor localization and risk factors. It covers the different overall treatment approaches including RT either as part of a multimodal treatment strategy or as a sole treatment and is accompanied by a summary on ongoing clinical research pointing at future directions of RT in STS.

Abstract

Radiation therapy (RT) is an integral part of the treatment of adult soft-tissue sarcomas (STS). Although mainly used as perioperative therapy to increase local control in resectable STS with high risk features, it also plays an increasing role in the treatment of non-resectable primary tumors, oligometastatic situations, or for palliation. Modern radiation techniques, like intensity-modulated, image-guided, or stereotactic body RT, as well as special applications like intraoperative RT, brachytherapy, or particle therapy, have widened the therapeutic window allowing either dose escalation with improved efficacy or reduction of side effects with improved functional outcome. This review summarizes the current evidence for RT in adult STS including typical indications, outcomes, side effects, dose and fractionation regimens, and target volume definitions based on tumor localization and risk factors. It covers the different overall treatment approaches including RT either as part of a multimodal treatment strategy or as a sole treatment, namely its use as an adjunct to surgery in resectable STS (perioperative RT), as a primary treatment in non-resectable tumors (definitive RT), as a local treatment modality in oligometastatic disease or as palliative therapy. Due to the known differences in clinical course, general treatment options and, consequently, outcome depending on lesion localization, the main part of perioperative RT is divided into three sections according to body site (extremity/trunk wall, retroperitoneal, and head and neck STS) including the discussion of special applications of radiation techniques specifically amenable to this region. The review of the current evidence is accompanied by a summary on ongoing clinical research pointing at future directions of RT in STS.

Multimodale Therapie primärer, nicht metastasierter retroperitonealer Sarkome

Weichteilsarkome sind eine heterogene Gruppe von Tumoren mesenchymalen Ursprungs, die teilweise ein sehr unterschiedliches biologisches Verhalten zeigen. Retroperitoneale Weichteilsarkome (RSTS) machen 10 – 15% aller Weichteilsarkome aus. Behandlungsempfehlungen für RSTS basieren auf vorrangig retrospektiven Analysen mit geringer Evidenz, die in dieser Übersichtsarbeit dargestellt werden. Zentraler Pfeiler in der Behandlung des lokalisierten, nicht metastasierten RSTS ist die chirurgische Resektion im Sinne einer Kompartment-Resektion. Ziel ist dabei immer die allseitig vollständige Tumorentfernung mit mikroskopisch freien Resektionsrändern. Ist das Erreichen dieses Behandlungsziels mit der alleinigen Kompartment-Resektion fraglich oder besteht eine hohe Wahrscheinlichkeit für eine lokale Tumorrekurrenz bei high-grade Sarkomen, so sollte eine neoadjuvante Bestrahlung, gegebenenfalls mit intraoperativem Boost, im Rahmen eines multimodalen Therapieansatzes durchgeführt werden. Die in Analogie zu den Extremitätensarkomen zu favorisierende Anthrazyklin-basierte Chemotherapie hat ihren Stellenwert vorrangig in der Adjuvanz. Auch wenn ein onkologischer Vorteil durch eine adjuvante Chemotherapie für RSTS bisher nicht nachgewiesen ist, sollte bei high-grade Sarkomen die Indikation diskutiert werden. In Kenntnis der unterschiedlichen Krankheitsverläufe werden zunehmend an die unterschiedlichen histologischen Subtypen adaptierte Therapiekonzepte diskutiert und in Studien untersucht. Valide Empfehlungen lassen sich jedoch bisher nicht ableiten. Die Behandlung von RSTS-Patienten wie überhaupt von Patienten mit Sarkomen in Zentren mit entsprechender Expertise ist mit einer signifikanten Verbesserung der Prognose assoziiert und ist unbedingt anzustreben.

High-Grade Malignant Spindle Cell Sarcoma of the Pelvis Presenting With Bloody Diarrhea and Urinary Retention: A Rare Case With a Rare Presentation

Soft tissue sarcomas (STSs) are rare malignant tumors originating from mesenchymal cells. Extremities are the most commonly affected anatomical sites, and majority of them present as a painless mass. We present a very interesting case of high-grade spindle cell sarcoma of the pelvis manifested as urinary retention and bloody diarrhea. A 68-year-old male presented to the emergency department with abdominal pain, inability to void urine, and bloody diarrhea. Straight urinary catheterization retrieved 900 mL of urine, and a Foley catheter was placed. All laboratory workup including complete blood count, complete metabolic panel, and urinalysis were within normal limits, but computed tomography (CT) of the abdomen and pelvis with contrast was remarkable for bilateral moderate hydronephrosis and a large 14 x 9.1 cm pelvic mass fistulizing into the rectum. To better identify the extent of disease, magnetic resonance imaging (MRI) with contrast was performed, which also revealed a similar large pelvic mass fistulizing into the rectum. Core needle biopsy of the mass was performed, which showed malignant spindle and epithelioid neoplasm with necrosis consistent with high-grade sarcoma. This is a very rare presentation of STS, and, to the best of our knowledge, only few similar cases have been reported thus far.

Intraoperative radiation therapy (IORT) for soft tissue sarcoma - ESTRO IORT Task Force/ACROP recommendations

PURPOSE

To describe guidelines for the use of intraoperative radiation therapy (IORT) in the treatment of soft-tissue sarcomas (STS).

METHODS

A panel of experts in the field performed a systematic literature review, supplemented their clinical experience and developed recommendations for the use of IORT in the treatment of STS.

RESULTS

Based on the evidence from the systematic literature review and the clinical experience of the panel members, recommendations regarding patient selection, incorporation into multimodal treatment concepts and the IORT procedure itself are made. The rationale for IORT in extremity and retroperitoneal STS is summarized and results of the major series in terms of patient and treatment characteristics, oncological outcome and toxicity are presented. We define surgical factors, volumes for irradiation, technical requirements, dose prescription, recording and reporting, treatment delivery and care during the course of IORT covering the main IORT techniques used for the treatment of STS. In extremity STS, evidence originates from a few small prospective and mainly from retrospective single centre studies. Based on those reports, IORT containing-approaches result in very high local control rates with low rates of acute and late toxicity. In retroperitoneal sarcomas, evidence is derived from one prospective randomized trial, a few prospective and a large number of retrospective studies. The randomized trial compared IORT combined with moderate doses of postoperative external-beam radiation therapy (EBRT) to high-dose postoperative EBRT alone after gross total resection, clearly favouring the IORT-containing approach. These results have been confirmed by the prospective and retrospective studies, which similarly showed high local control rates with acceptable toxicity, mainly favouring combinations of preoperative EBRT and IORT.

CONCLUSIONS

IORT-containing approaches result in high rates of local control with low to acceptable toxicity rates. Based on the available evidence, we made recommendations for the use of IORT in STS. Clinicians and researchers are encouraged to use these guidelines in clinical routine as well as in the design of future trials.

Intraoperative Strahlentherapie – Indikationen und Optionen in der Viszeralchirurgie

Hintergrund

Die intraoperative Strahlentherapie (IORT) ermöglicht durch die chirurgische Exposition des Tumors und des Tumorbetts eine hohe Präzision, welche eine hohe Strahlendosis im Bereich des Tumors zulässt und gleichzeitig gesundes Gewebe als den dosislimitierenden Faktor vor Strahlung schützt. Aus diesem Grund bietet die IORT besonders dann einen Vorteil, wenn die lokale Tumorkontrolle das Langzeitüberleben entscheidend beeinflusst und Funktionserhalt ermöglicht.

Ziel der Arbeit

Die in dieser Übersichtsarbeit aufgearbeiteten Erkenntnisse aus der Literaturrecherche erlauben einen evidenzbasierten Umgang hinsichtlich Indikationen und Therapieoptionen der IORT für intraabdominelle Tumoren.

Ergebnisse und Schlussfolgerung

Die Effektivität der IORT kann anhand der vorhandenen Evidenzlage nicht abschließend beurteilt werden, jedoch ist die IORT als Ergänzung der multimodalen Therapie bei (Rezidiv‑)Rektumkarzinomen und Sarkomen aktiv im klinischen Alltag etabliert. Magen- und Pankreaskarzinome stellen weitere Indikationen dar; ergänzende Studien sind jedoch notwendig, um die Rolle der IORT hier klar zu definieren. Ein wesentlicher Faktor, damit für Patienten mit primärem Karzinom und insbesondere für Patienten mit lokalem Rezidiv verbesserte lokale Rezidiv- und Überlebensraten erreicht werden können, scheint die Patientenselektion zu sein.

Soft Tissue Tumors of the Abdomen and Retroperitoneum

Soft tissue tumors of the abdomen and retroperitoneum encompass a wide range of benign and malignant neoplasms. Retroperitoneal sarcomas, the most common, are composed of rare malignancies with numerous histiotypes. Surgery remains the cornerstone of treatment and the only curative option for retroperitoneal sarcomas. With histiotype-dependent local and distant recurrences, it is imperative these cases are discussed in a multidisciplinary tumor board setting at specialized sarcoma centers. This review discusses the current evidence for the management of abdominal and retroperitoneal soft tissue tumors, with particular focus on retroperitoneal sarcomas and desmoid tumors.

Dedifferentiated Liposarcoma: Systemic Therapy Options

OPINION STATEMENT

Over the last several years, the systemic treatment landscape for dedifferentiated liposarcoma (DDLPS) has notably expanded. Historically, systemic therapy options have been limited to cytotoxic chemotherapy agents, including doxorubicin, ifosfamide, gemcitabine, and docetaxel, that were shown to have efficacy in unselected populations of patients with soft tissue sarcomas. More recently, however, there have been phase II and III trials establishing clinical benefit of the cytotoxic agents trabectedin and eribulin along with the tyrosine kinase inhibitor pazopanib in patients with advanced liposarcoma and DDLPS. Additionally, there are several investigational targeted therapies that have incorporated advances in the understanding of DDLPS disease biology, exploiting the fact that nearly all such tumors include highly amplified expression of MDM2 and CDK4. Recent clinical trials have supported the benefit of the CDK4 inhibitor abemaciclib and the nuclear export inhibitor selinexor and support continued development of anti-MDM2 therapies, with particular attention to the bone marrow toxicity and resultant thrombocytopenia that has thus far limited their use. In contrast, the checkpoint inhibitors pembrolizumab and nivolumab remain of questionable benefit, although these immunotherapy drugs may have a role when combined with other therapeutic agents. Ongoing phase III trials will clarify the role of these novel agents. Future directions include directly comparing current standard-of-care options and newer therapies, developing synergistic combinations of novel agents, and evaluating their role in patients with localized DDLPS.

Significance of intraoperative radiation therapy and high cumulative radiation doses in retroperitoneal soft tissue sarcoma

INTRODUCTION

In retroperitoneal soft tissue sarcoma (STS) local recurrence (LR) rates remain high despite more aggressive surgical approaches. Since wide resection margins cannot be achieved in all patients, application of intraoperative radiation therapy (IORT) has been frequently discussed. Still, the significance of IORT in multimodal treatment of retroperitoneal STS remains unclear.

MATERIAL AND METHODS

Patients undergoing resection of primary or recurrent retroperitoneal STS at the University of Heidelberg Department of General, Visceral and Transplantation Surgery were retrospectively analyzed. Univariate Kaplan-Meyer and multivariate Cox regression analyses were performed to identify predictors of LR-free survival and to investigate the impact of IORT and high cumulative radiation doses. Analyses with propensity-score matched subgroups for IORT and cumulative radiation dose were performed to control for selection bias. Subgroup analyses for patients with retroperitoneal liposarcoma were likewise performed.

RESULTS

272 patients were identified. Recurrent tumors, histology of dedifferentiated liposarcoma or unclassified sarcoma and microscopically incomplete resection were associated with decreased LR-free survival. In liposarcoma, only recurrent and dedifferentiated tumors were confirmed as poor prognostic factors concerning LR. IORT and cumulative radiation doses exceeding 60 Gy did not influence LR rates (estimated 5-year LR-free survival: IORT: 39%, non-IORT: 46%; p = 0.79).

CONCLUSION

In this retrospective evaluation, additional application of IORT does not significantly influence oncological outcome in retroperitoneal soft tissue sarcoma. Randomized trials are needed to clarify the benefit of IORT.

Giant retroperitoneal liposarcoma: A case report and literature review

Retroperitoneal liposarcomas are a heterogeneous group of mesenchymal tumours that have a wide spectrum of histological subtypes and vague clinical presentations. Herein, we present the case of a 75-year-old man with anorexia, weight loss of 7 kg, and a growing abdominal circumference within a span of 6 weeks. Computed tomography of the abdomen and pelvis showed a large mass that filled almost the entire abdominal cavity. After consultation with a multidisciplinary tumour board, en bloc resection of the tumour was performed. In addition, the left kidney and a part of the left diaphragm were removed. The tumour measured 35 × 29 × 20.5 cm and weighed 11.6 kg. The histological report confirmed low-grade dedifferentiated liposarcoma with scarce atypical adipocytes, lipoblasts containing spindle cell, pleomorphic, and chondroid components. The patient had uneventful recovery and remained stable during the follow-up period. We report this case to highlight the need for customized surgical oncological measures in the treatment of solid abdominal tumours due to locoregional invasion that usually necessitates en bloc resection.

Update in pelvic and retroperitoneal sarcoma management: The role of compartment surgery

Surgery for retroperitoneal sarcomas should be "en bloc" compartmental, which involves resection of unaffected organs. Its upfront use is key, providing a high percentage of resections with negative margins, resulting in a better local control and increased survival in many patients. Preservation of organs should be done in an individualized manner, especially in the pelvic location, and adapted to the histological aggressiveness of the tumor. Preoperative biopsy is able to establish the diagnosis of sarcoma subtype and consequently an adequate perioperative strategy. These patients should be managed by expert surgeons at referral centers with multidisciplinary units and oncology committees. The use of chemotherapy and radiotherapy is not yet well defined, so it is only recommended at referral centers with clinical trials. Currently, this is the only option to offer the best morbidity and mortality rates, as well as possible improvements in the survival of these patients.

(Neo)adjuvant chemotherapy and interdigitated split-course hyperfractionated radiation in high risk soft tissue sarcoma - Results from a large single-institution series

A single-institution series using a (neo)adjuvant chemotherapy and interdigitated hyperfractionated split-course radiation therapy (CRT) treatment protocol for soft tissue sarcoma was reviewed. Our specific aims were to study recurrence rates and long-term toxicity. Between 1998 and 2016, 89 patients with non-metastatic soft tissue sarcoma were treated with surgery combined with six courses of doxorubicin and ifosfamide and hyperfractionated radiation therapy (42-60 Gy/1.5 Gy twice daily). Patients were considered being at high risk if tumour malignancy grade was high and the tumour fulfilled at least two of the following criteria: size >8 cm, presence of necrosis or vascular invasion. The mean age of the patients was 50.7 years. With a median follow-up of 5.4 years for survivors, the local control rate was 81.4%. Six (7%) patients progressed during neoadjuvant CRT. Seven (8%) patients discontinued the treatment due to toxicity. Eighty-six patients were operated and three (3%) of these developed a long-term complication. The estimated metastasis-free survival was 47.6% and overall survival 53.0% at five years. The limb-salvage rate was 93%. The limb-salvage rate, local control and complication rates were good in these patients with high risk soft tissue sarcoma. Metastases-free survival and overall survival rates were less satisfactory, reflecting the aggressive nature of these tumours.

Well-differentiated liposarcoma and dedifferentiated liposarcoma: An updated review

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

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.

Retroperitoneal or mesenteric primary liposarcoma: clinical and prognostic evaluations on five cases

BACKGROUND

Retroperitoneal or mesenteric primary liposarcoma is a malignant neoplasia whose prognosis depends on the biological variants, the radical resection surgery and the histological subtypes, as well as on local and remote recurrences. Liposarcoma is the most common variant of this tumour among tumours of soft retroperitoneal tissue. The purpose of this study is to evaluate whether the treatment of this disease, carried out at the Ivrea Hospital for urgent reasons, may be considered in line with the experience of high-volume Centres.

PATIENTS AND METHODS

Between 1982 and 2016 five patients were hospitalized with a diagnosis of acute abdomen due to retroperitoneal or mesenteric primary liposarcoma: one myxoid of the mesentery, one well-differentiated of lesser epiploon, one well-differentiated of mesentery, and two dedifferentiates of the retroperitoneum.

RESULTS

The five patients, all males, had a average age of 59 years (range 48-86) and were all subjected to general anaesthesia and open technique for total tumour removal. Only the patient with the myxoid liposarcoma had two recurrences. All are alive and healthy after a follow-up of 177 months (range 9-420).

CONCLUSION

These tumours should be removed radically, if necessary in conjunction with contiguous organs. Rarity and therapeutic complexity require a treatment, sometimes even multimodal, in highvolume centres. Patients admitted in General Surgery Unit for unpostponable urgency should be operated by surgeons experienced in the treatment of abdominal disease to achieve survival results in line to those achievable in Hub Centres.

Randomized Controlled Trials in Soft Tissue Sarcoma: We Are Getting There!

Soft tissue sarcoma (STS) is a family of malignancies for which individual management decisions can be complex. There is a paucity of level 1 evidence, as the rarity and heterogeneity of STS pose challenges to the design and execution of randomized controlled trials. Radiotherapy (RT) is routinely used to facilitate function-preserving surgery and to improve local control. Delivery of RT in the preoperative setting can decrease chronic toxicities at the cost of increased wound complications in the short-term. The role of adjuvant systemic therapies remains controversial in adult STS.

Intraoperative radiotherapy: review of techniques and results

Intraoperative radiotherapy (IORT) is a technique that involves precise delivery of a large dose of ionising radiation to the tumour or tumour bed during surgery. Direct visualisation of the tumour bed and ability to space out the normal tissues from the tumour bed allows maximisation of the dose to the tumour while minimising the dose to normal tissues. This results in an improved therapeutic ratio with IORT. Although it was introduced in the 1960s, it has seen a resurgence of popularity with the introduction of self-shielding mobile linear accelerators and low-kV IORT devices, which by eliminating the logistical issues of transport of the patient during surgery for radiotherapy or building a shielded operating room, has enabled its wider use in the community.

Electrons, low-kV X-rays and HDR brachytherapy are all different methods of IORT in current clinical use. Each method has its own unique set of advantages and disadvantages, its own set of indications where one may be better suited than the other, and each requires a specific kind of expertise.

IORT has demonstrated its efficacy in a wide variety of intra-abdominal tumours, recurrent colorectal cancers, recurrent gynaecological cancers, and soft-tissue tumours. Recently, it has emerged as an attractive treatment option for selected, early-stage breast cancer, owing to the ability to complete the entire course of radiotherapy during surgery. IORT has been used in a multitude of roles across these sites, for dose escalation (retroperitoneal sarcoma), EBRT dose de-escalation (paediatric tumours), as sole radiation modality (early breast cancers) and as a re-irradiation modality (recurrent rectal and gynaecological cancers).

This article aims to provide a review of the rationale, techniques, and outcomes for IORT across different sites relevant to current clinical practice.

Neoadjuvant chemotherapy in soft tissue sarcomas: latest evidence and clinical implications

Soft tissue sarcomas are a rare and multifaceted group of solid tumours. Neoadjuvant chemotherapy is increasingly used to limit loss of function after wide surgical excision with the ultimate aim of improving patient survival. Recently, advances in the identification of effective treatment strategies and improvements in patient risk stratification have been reached. A randomized trial demonstrated that neoadjuvant epirubicin and ifosfamide improves survival of patients affected by five high-risk soft tissue sarcoma histologies of trunk and extremities, including undifferentiated pleomorphic sarcoma, myxoid liposarcoma, synovial sarcoma, malignant peripheral nerve sheath tumours, and leiomyosarcoma. Selection of patients for these treatments is expected to be improved by the eighth edition of the American Joint Committee on Cancer (AJCC) TNM staging system, as it tailors T-stage categories on primary tumour site and considers a prognostic nomogram for retroperitoneal sarcoma, which also includes soft tissue sarcoma histology and other patient and tumour features not directly included in the TNM staging. Within this framework, this article will present neoadjuvant treatment strategies for high-risk soft tissue sarcoma, emphasizing the most recent advances and discussing the need for further research to improve the effectiveness of neoadjuvant treatments.

Intraoperative radiation therapy (IORT) in soft-tissue sarcoma

Soft-tissue sarcoma (STS) represent a rare tumor entity, accounting for less than 1% of adult malignancies. The cornerstone of curative intent treatment is surgery with free margins, although the extent of the surgical approach has been subject to change in the last decades. Multimodal approaches usually including radiation therapy have replaced extensive surgical procedures in order to preserve functionality while maintaining adequate local control. However, the possibility to apply adequate radiation doses by external beam radiation therapy (EBRT) can be limited in some situation especially in case of directly adjacent organs at risk with low radiation tolerance. Application of at least a part of the total dose via intraoperative radiation therapy (IORT) with a single fraction during the surgical procedure may overcome those limitations, because radiosensitive structures can be moved out of the radiation field resulting in reduced toxicity while the enhanced biological effectivity of the high single dose improves local control. The current review summarizes rationale, techniques, oncological and functional outcomes including possible pitfalls and associated toxicities based on the published literature for IORT focusing on extremity and retroperitoneal STS. In extremity STS, combination of limb-sparing surgery, IORT and pre- or postoperative EBRT with moderate doses consistently achieved excellent local control rates at least comparable to approaches using EBRT alone but usually including patient cohorts with higher proportions of unfavourable prognostic factors. Further on, IORT containing approaches resulted in very high limb preservation rates and good functional outcome, probably related to the smaller high dose volume. In retroperitoneal STS, the combination of preoperative EBRT, surgery and IORT consistently achieved high local control rates which seem superior to surgery alone or surgery with EBRT at least with regard to local control and in some reports even to overall survival. Further on, preoperative EBRT in combination with IORT seems to be superior to the opposite combination with regard to local control and toxicity. No major differences in wound healing disturbances or postoperative complication rates can be observed with IORT compared to non-IORT containing approaches. Neuropathy of major nerves remains a dose limiting toxicity requiring dose restrictions or exclusion from target volume. Gastrointestinal structures and ureters should be excluded from the IORT area whenever possible and the IORT volume should be restricted to the available minimum. Nevertheless, IORT represents an ideal boosting method if combined with EBRT and properly executed by experiences users which should be further evaluated preferably in prospective randomized trials.

Primary retroperitoneal soft tissue sarcoma: Imaging appearances, pitfalls and diagnostic algorithm

Although retroperitoneal sarcomas are rare tumours, they can be encountered by a wide variety of clinicians as they can be incidental findings on imaging or present with non specific symptoms and signs. Surgical resection can offer hope of cure and patient outcomes are improved when patients are managed in high-volume specialist centers. Failure to recognize retroperitoneal sarcomas on imaging can lead to inappropriate management in inexperienced centers. Therefore it is critical that a diagnosis of retroperitoneal sarcoma should be considered in the differential diagnosis of a retroperitoneal mass with prompt referral to a soft tissue sarcoma unit. In particular, the most common retroperitoneal sarcoma subtypes, liposarcoma and leiomyosarcoma, have characteristic imaging appearances which are discussed. This review therefore aims to set the context and guide clinicians through a diagnostic pathway for retroperitoneal masses in adults which arise extrinsic to the solid abdominal viscera.

(Neo)adjuvant treatment in localised soft tissue sarcoma: The unsolved affair

Soft tissue sarcomas (STS) are rare and heterogeneous tumours. A correct definition of STS is imperative from the very beginning of disease management, to guide the diagnostic and imaging work-up, and help to establish the prognosis on which the therapeutic strategy will be based. Over the last few years, many efforts have been made to identify characteristics that could predict disease behaviour and to enrich the therapeutic armamentarium against the advanced disease, that is still characterised by poor prognosis. Surgery remains the milestone of treatment for localised STS, whereas many uncertainties regarding the role of adjuvant and neoadjuvant treatment persist. Some controlled evidence is available, but often conflicting and insufficient to make chemotherapy (CT) a standard practice and, currently, a common and shared strategy does not exist. The biggest question concerns the prospective identification of the subgroup of patients who would benefit the most from (neo)adjuvant therapies. In light of the growing understanding of different biologies and sensitivities of the various sarcoma subtypes, the value of histology in the selection of peri-operative treatments is one of the most intriguing topics under discussion. In this perspective, a new generation of neoadjuvant trials have been planned and are currently ongoing. The aim of this review was to rekindle interest in the long-standing topic of (neo)adjuvant CT in localised STS, providing an update on its role in sarcomas' management and highlighting future directions and consequential factors needed to further improve outcomes in this disease.

Looking for answers: the current status of neoadjuvant treatment in localized soft tissue sarcomas

PURPOSE

Sarcomas are a rare and heterogeneous variant of cancer. The standard of care treatment involves surgical resection with radiation in high-risk patients. Despite appropriate treatment approximately 50 % of patients will suffer and die from recurrent disease. The purpose of this article is to review the current evidence concerning the use of neoadjuvant chemotherapy with or without radiation in soft tissue sarcomas.

METHODS

An in-depth literature search was conducted using Ovid Medline and PubMed.

RESULTS

The most active chemotherapeutic agents in sarcoma are anthracyclines and ifosfamide. Adjuvant chemotherapy trials show only minimal benefit. Neoadjuvant chemotherapy offers the potential advantage of reducing the extent of surgery, increasing the limb salvage rate, early exposure of micrometastatic disease to chemotherapy, and assessment of tumor response to chemotherapy. Some retrospective and phase II trials suggest a benefit to neoadjuvant chemotherapy. Unfortunately, no clearly positive phase III prospectively randomized trials exist for neoadjuvant therapy in soft tissue sarcomas.

CONCLUSIONS

The current neoadjuvant chemotherapy trials that do exist are heterogeneous resulting in conflicting results. However, neoadjuvant chemotherapy with or without radiation can be considered in patients with high-risk disease in an attempt to improve long-term outcomes.

[Radiotherapy for retroperitoneal sarcomas]

The management of retroperitoneal sarcoma can be very challenging, and the quality of initial treatment strategy appears to be a crucial prognostic factor. En bloc surgery is currently the standard of care for these rare tumours and perioperative treatments such as chemotherapy or radiotherapy have not been validated yet. However, local-regional relapse constitutes the most common disease course. While adjuvant radiotherapy is less and less common due to gastrointestinal toxicities, preoperative radiation therapy offers numerous advantages and is being evaluated as part of a national multicentre phase II study (TOMOREP trial) and is the subject of a European randomized phase III study (STRASS trial). The objective of this article is to present data on preoperative irradiation in terms of dose, volumes and optimal radiotherapy techniques for the treatment of this rare disease.

Oncology outcomes in Retroperitoneal sarcomas: Prognostic factors in a Retrospective Cohort study

INTRODUCTION

Retroperitoneal sarcomas are a rare group of malignant soft tissue tumors with a generally poor prognosis. The aim of the study was to define the demographic characteristics and prognostic factors for patients with retroperitoneal sarcomas (RPS) in a Tertiary Referral Center at Mexico.

METHODS

A retrospective study of patients with RPS treated from January 2005 to December 2012 at the National Cancer Institute at Mexico. Patient, tumor and treatment variables were analyzed including use of adjuvant therapy and survival status. Survival and local recurrence curves were estimated using the Kaplan-Meier method.

RESULTS

Ninety-five patients with a mean age of 47 years with retroperitoneal sarcoma were included. Median follow-up was 25 months (range 1-108 months). The average tumor size was 23.7 cm. Histology, 58 (61.1%) were liposarcoma, 14 (14.7%), leiomyosarcomas and 23 (24.2%) were from other histologies. In 64 (67.4%) patients were high-grade malignancies. The median survival was 51 months for patients with complete resection, 25.1 months for those with incomplete resection, and 4.4 months for those with unresectable tumors. Complete resection (p = 0.0001), and liposarcoma (p = 0.03) were prognostic factors for overall survival.

CONCLUSION

In this study of patients with retroperitoneal, complete resection and liposarcoma histology are prognostic factors related to the disease-free and overall survival. Patients approached with curative intent should undergo aggressive attempts at complete surgical resection.

Neoadjuvant radiotherapy for retroperitoneal sarcoma: A systematic review

BACKGROUND AND OBJECTIVES

The multi-modal treatment of retroperitoneal sarcoma has seen increased use of neoadjuvant radiation. However, its effect on local recurrence and survival remain controversial. We aimed to synthesize and evaluate the literature.

METHODS

The review was conducted according the recommendation of the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) group with pre-specified inclusion and exclusion criteria.

RESULTS

Of 8,701 citations collected, 15 articles reported on 464 patients. The median age was 56 years (45-64). The predominant histological subtypes were liposarcoma (51.54%) and leiomyosarcoma (23.26%). Tumor differentiation composed of 37.1% well-, 12.8% moderate-, 46.0% poorly-, and 4.1% undifferentiated. Most studies featured external beam radiation therapy (EBRT) treatment regimen with some who included patients treated with IMRT instead. Median follow-up averaged 41.4 months (19-106 months). Median 5-year OS, PFS, and LRR rates were 58%, 71.5%, and 25%. Using the NCI CTCAE, toxicities from Grade 1 (Mild) through Grade 5 (death) were experienced by 18.8%, 10.2%, 16.3%, 0.7%, and 1.6% of patients.

CONCLUSIONS

NART is a safe to use for RPS, but its effect toward survival and local control remains unclear. Without randomized control trials, common reporting criteria for pro- and retrospective studies are needed to allow comparison between studies. J. Surg. Oncol. 2016;113:628-634. © 2016 Wiley Periodicals, Inc.

Dedifferentiated Liposarcoma: Updates on Morphology, Genetics, and Therapeutic Strategies

Well-differentiated liposarcoma (WDL) and dedifferentiated liposarcoma (DDL) form the largest subgroup of liposarcomas, and represent a morphologic and behavioral spectrum of 1 disease entity, which arises typically in middle to late adult life, most frequently within the retroperitoneum or extremities. DDL is defined as nonlipogenic sarcoma that is juxtaposed to WDL, occurs as a recurrence of WDL or which can arise de novo, and typically has the appearance of undifferentiated pleomorphic or spindle cell sarcoma. DDL have a propensity for local recurrence, whereas distant metastasis is rarer, and behavior is related to anatomic site, with retroperitoneal neoplasms showing a significantly worse prognosis. Surgical resection remains the mainstay of treatment, and medical options for patients with aggressive recurrent or metastatic disease are limited. DDL share similar genetic abnormalities to WDL, with high-level amplifications of chromosome 12q14-15, including the MDM2 and CDK4 cell cycle oncogenes, and DDL harbor additional genetic changes, particularly coamplifications of 6q23 and 1p32. Novel therapies targeted at the gene products of chromosome 12 are being tested in clinical trials. We review the pathology and genetics of DDL, discussing morphologic patterns, immunohistochemical and genetic findings, the differential diagnosis, and future therapeutic strategies.

Preoperative radiotherapy for extremity soft tissue sarcoma; past, present and future perspectives on dose fractionation regimens and combined modality strategies

INTRODUCTION

This critical review aims to summarize published data on limb sparing surgery for extremity soft tissue sarcoma in combination with pre-operative radiotherapy (RT).

METHODS

This review is based on peer-reviewed publications using a PubMed search on the MeSH headings "soft tissue sarcoma" AND "preoperative radiotherapy". Titles and abstracts screened for data including "fraction size AND/OR total dose AND/OR overall treatment time", "chemotherapy", "targeted agents AND/OR tyrosine kinase inhibitors", are collated. Reference lists from some articles have been studied to obtain other pertinent articles. Additional abstracts presented at international sarcoma meetings have been included as well as information on relevant clinical trials available at the ClinicalTrials.gov website.

RESULTS

Data are presented for the conventional regimen of 50-50.4Gy in 25-28 fractions in 5-6 of weeks preoperative external beam RT with respect to the regimen's local control probability compared to surgery alone, as well as acute and late toxicities. The rationale and outcome data for hypofractionated and/or reduced dose regimens are discussed. Finally, combination schedules with conventional chemotherapy and/or targeted agents are summarized.

CONCLUSION

Outside the setting of well-designed prospective clinical trials, the conventional 50Gy in 5-6week schedule should be considered as standard. However, current and future studies addressing alternative fraction size, total dose, overall treatment time and/or combination with chemotherapy or targeted agents may reveal regimens of equal or increased efficacy with reduced late morbidities.

Long-term Oncologic Outcomes After Neoadjuvant Radiation Therapy for Retroperitoneal Sarcomas

OBJECTIVE

To evaluate long-term survival among patients undergoing radiation therapy (RT), followed by surgical resection of retroperitoneal sarcomas (RPS).

BACKGROUND

Despite a lack of level 1 evidence supporting neoadjuvant RT for RPS, its use has increased substantially over the past decade.

METHODS

The 1998-2011 National Cancer Data Base was queried to identify patients who underwent resection of RPS. Subjects were grouped by use of neoadjuvant RT. Perioperative variables and outcomes were compared. Multivariable logistic regression was performed to assess predictors of neoadjuvant RT. Groups were propensity matched using a 2:1 nearest neighbor algorithm and short-term outcomes were compared. Finally, long-term survival was evaluated using the Kaplan-Meier method, with comparisons based on the log-rank test.

RESULTS

A total of 11,324 patients were identified. Neoadjuvant RT was administered to 696 patients (6.1%). During the study period, preoperative RT use increased from 4% to nearly 15%. Male sex, tumor size larger than 5 cm, treatment at an academic/research program, and higher tumor grade all predicted neoadjuvant RT administration. After propensity matching, the only difference in baseline characteristics was the use of neoadjuvant chemotherapy. Although neoadjuvant RT was associated with a higher rate of negative margins (77.5% vs 73.0%; P = 0.014), there was no corresponding improvement in 5-year survival (53.2% vs 54.2%; P = 0.695).

CONCLUSIONS

Despite the increasing use of neoadjuvant RT for patients with RPS, the survival benefit associated with this treatment modality remains unclear. Continued investigation is needed to better define the role of RT among patients with RPS.