Comparison of local recurrence with conventional and intensity-modulated radiation therapy for primary soft-tissue sarcomas of the extremity

Neutrophil-to-lymphocyte ratio for the prediction of soft tissue sarcomas response to pre-operative radiation therapy

PURPOSE/OBJECTIVE

This study aims to assess the prognostic value of the neutrophil-to-lymphocyte ratio (NLR) in soft tissue sarcomas (STS) treated with pre-operative hypofractionated radiotherapy (HFRT).

MATERIALS/METHODS

This retrospective analysis included patients treated with pre-operative HFRT of 30 Gy in 5 fractions between 2016 and 2023. Clinical, demographic, and complete blood count (CBC) data were collected. NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. Only patients with CBCs conducted within 6 months after radiotherapy were included. Cox proportional-hazard regression models were used to assess the impact of NLR and different variables on outcomes. Kaplan Meier were used to illustrate survival curves. A p-value < 0.05 was considered significant, and 95 % confidence intervals (CI) were employed.

RESULTS

A total of 40 patients received HFRT and had CBCs within 6 months after radiotherapy. There were 17 (42.5 %) females and 23 (57.5 %) males with a mean age of 66 years. The mean largest tumor size dimension was 7.1 cm, and the mean NLR post-RT was 5.3. The most frequent histological subtypes were myxofibrosarcoma (17.5 %), pleomorphic spindle cell sarcoma (10 %), leiomyosarcoma (7.5 %), and myxoid liposarcoma (5 %). The median follow-up period was 15.4 months. From all patients, 14 patients had disease progression, 12 metastatic disease and 3 died of disease. Multivariable Cox proportional-hazards regression analysis displayed that a higher post-RT NLR was associated with worse disease-free survival (DFS) (HR: 1.303 [1.098-1.548], p = 0.003), and distant metastasis-free survival (DMFS) (HR: 1.38 [1.115-1.710], p = 0.003). Moreover, post-NLR ≥ 4 as a single variable was associated with worse DFS, DMFS, but not worse local recurrence or overall survival.

CONCLUSION

This study is the first to evaluate NLR as a prognostic biomarker in STS patients treated with pre-operative radiotherapy. A higher NLR after pre-operative radiotherapy was associated with increased disease progression.

UK guidelines for the management of soft tissue sarcomas

Soft tissue sarcomas (STS) are rare tumours arising in mesenchymal tissues and can occur almost anywhere in the body. Their rarity, and the heterogeneity of subtype and location, means that developing evidence-based guidelines is complicated by the limitations of the data available. This makes it more important that STS are managed by expert multidisciplinary teams, to ensure consistent and optimal treatment, recruitment to clinical trials, and the ongoing accumulation of further data and knowledge. The development of appropriate guidance, by an experienced panel referring to the evidence available, is therefore a useful foundation on which to build progress in the field. These guidelines are an update of the previous versions published in 2010 and 2016 [1, 2]. The original guidelines were drawn up by a panel of UK sarcoma specialists convened under the auspices of the British Sarcoma Group (BSG) and were intended to provide a framework for the multidisciplinary care of patients with soft tissue sarcomas. This iteration of the guidance, as well as updating the general multidisciplinary management of soft tissue sarcoma, includes specific sections relating to the management of sarcomas at defined anatomical sites: gynaecological sarcomas, retroperitoneal sarcomas, breast sarcomas, and skin sarcomas. These are generally managed collaboratively by site specific multidisciplinary teams linked to the regional sarcoma specialist team, as stipulated in the recently published sarcoma service specification [3]. In the UK, any patient with a suspected soft tissue sarcoma should be referred to a specialist regional soft tissues sarcoma service, to be managed by a specialist sarcoma multidisciplinary team. Once the diagnosis has been confirmed using appropriate imaging and a tissue biopsy, the main modality of management is usually surgical excision performed by a specialist surgeon, combined with pre- or post-operative radiotherapy for tumours at higher risk for local recurrence. Systemic anti-cancer therapy (SACT) may be utilised in cases where the histological subtype is considered more sensitive to systemic treatment. Regular follow-up is recommended to assess local control, development of metastatic disease, and any late effects of treatment.

Factors Influencing Long-Term Local Recurrence, Distant Metastasis, and Survival in Patients with Soft Tissue Sarcoma of the Extremities Treated with Radiotherapy

INTRODUCTION

The prognostic factors for extremity soft-tissue sarcomas (ESTSs) treated with multimodal surgery and radiotherapy (RT) remain a subject of debate across diverse and heterogeneous studies.

METHODS

We retrospectively analyzed nonmetastatic ESTS patients treated with RT between 2007 and 2020 in Strasbourg, France. We assessed local control (LC), distant control (DC), overall survival (OS), and complications.

RESULTS

A total of 169 patients diagnosed with localized ESTS were included. The median age was 64 years (range 21-94 years). ESTS primarily occurred proximally (74.6%) and in the lower limbs (71%). Most tumors were grade 2-3 (71.1%), deep-seated (86.4%), and had R0 margins (63.9%). Most patients were treated with helical tomotherapy (79.3%). The median biologically effective dose (BED) prescribed was 75 BEDGy4 (range 45.0-109.9). The median follow-up was 5.5 years. The 5- and 10-year LC, DC, and OS rates were 91.7%, 76.8%, and 83.8% and 84.2%, 74.1%, and 77.6%, respectively. According to the univariate analysis, LC was worse for patients who received less than 75 BEDGy4 (p = 0.015). Deep tumors were associated with worse OS (p < 0.05), and grade 2-3 and undifferentiated pleomorphic sarcoma (UPS) were linked to both shorter DC and shorter OS (p < 0.05). IMRT was associated with longer LC than 3DRT (p = 0.018). Multivariate analysis revealed that patients with liposarcoma had better OS (p < 0.05) and that patients with distant relapse had shorter OS (p < 0.0001).

CONCLUSION

RT associated with surgical resection was well tolerated and was associated with excellent long-term rates of LC, DC, and OS. Compared with 3DRT, IMRT improved local control. Liposarcoma was a favorable prognostic factor for OS. Intermediate- and high-grade tumors and deep tumors were associated with lower DC and OS.

Update on Dosing and Fractionation for Neoadjuvant Radiotherapy for Localized Soft Tissue Sarcoma

OPINION STATEMENT

Neoadjuvant radiotherapy (RT) over 5-6 weeks with daily doses of 1.8-2.0 Gy to a total dose of 50-50.4 Gy is standard of care for localized high-grade soft tissue sarcomas (STS) of the extremities and trunk wall. One exception is myxoid liposarcomas where the phase II DOREMY trial applying a preoperative dose of 36 Gy in 2 Gy fractions (3-4 weeks treatment) has achieved excellent local control rates of 100% after a median follow-up of 25 months.Hypofractionated preoperative RT has been investigated in a number of phase II single-arm studies suggesting that daily doses of 2.75-8 Gy over 1-3 weeks can achieve similar oncological outcomes to conventional neoadjuvant RT. Prospective data with direct head-to-head comparison to conventional neoadjuvant RT investigating oncological outcomes and toxicity profiles is eagerly awaited.For the entire group of retroperitoneal sarcomas, RT is not the standard of care. The randomized multi-center STRASS trial did not find a benefit in abdominal recurrence-free survival by the addition of preoperative RT. However, for the largest histological subgroup of well-differentiated and grades I and II dedifferentiated liposarcomas, the STRASS trial and the post-hoc propensity-matched STREXIT analysis have identified a possible benefit in survival by preoperative RT. These patients deserve to be informed about the pros and cons of preoperative RT while the longer follow-up data from the STRASS trial is awaited.

Novel Postoperative Hypofractionated Accelerated Radiation Dose-Painting Approach for Soft Tissue Sarcoma

Purpose

Hypofractionated radiation therapy (RT) offers benefits in the treatment of soft tissue sarcomas (STS), including exploitation of the lower α/β, patient convenience, and cost. This study evaluates the acute toxicity of a hypofractionated accelerated RT dose-painting (HARD) approach for postoperative treatment of STS.

Methods and Materials

This is a retrospective review of 53 consecutive patients with STS who underwent resection followed by postoperative RT. Standard postoperative RT dosing for R0/R1/gross disease with sequential boost (50 Gy + 14/16/20 Gy in 32-35 fractions) were replaced with dose-painting, which adapts dose based on risk of disease burden, to 50.4 and 63, 64.4, 70 Gy in 28 fractions, respectively. The first 10 patients were replanned with a sequential boost RT approach and dosimetric indices were compared. Time-to-event outcomes, including local control, regional control, distant control, and overall survival, were estimated with Kaplan-Meier analysis.

Results

Median follow-up was 25.2 months. Most patients had high-grade (59%) STS of the extremity (63%) who underwent resection with either R1 (40%) or close (36%) margins. Four patients experienced grade 3 acute dermatitis which resolved by the 3-month follow-up visit. The 2-year local control, regional control, distant control, and overall survival were 100%, 92%, 68%, and 86%, respectively. Compared with the sequential boost plan, HARD had a significantly lower field size (total V50 Gy; P = .002), bone V50 (P = .031), and maximum skin dose (P = .008). Overall treatment time was decreased by 4 to 7 fractions, which translated to a decrease in estimated average treatment cost of $3056 (range, $2651-$4335; P < .001).

Conclusions

In addition to benefits in cost, convenience, and improved biologic effect in STS, HARD regimen offers a safe treatment approach with dosimetric advantages compared with conventional sequential boost, which may translate to improved long-term toxicity.

The incidence, risk factors and outcomes of wound complications after preoperative radiotherapy and surgery for high grade extremity soft tissue sarcomas: A 14-year retrospective study

OBJECTIVE

The aim of this study was to analyze the wound complication (WC) rate and to determine the risk factors for WC in patients with soft tissue sarcoma treated with preoperative radiotherapy followed by surgical resection.

METHODS

Using the database of Oxford University Hospital (OUH) we retrospectively studied 126 cases of soft tissue sarcomas treated with preoperative radiotherapy and surgery between 2007 and 2021. WC were defined as minor wound complication (MiWC) not requiring surgical intervention or major wound complication (MaWC) if they received a secondary surgical intervention. Univariate and multiple regression analyses were performed using frequency of WC and MaWC as a dependent variable.

RESULTS

The incidence of WC and MaWC was 43.7% (55/126) and 19% (24/126). Age (OR:1.03, 95%CI: 1.00-1.06, p = 0.016), tumor size (OR:1.11, 95%CI:1.01-1.21, p = 0.027) and tumor site namely proximal lower limb vs upper limb (OR:10.87, 95%CI 1.15-103.03, p = 0.038) were risk factors on multivariate analysis. In nested case control analysis, the incidence of MaWC was 43.6% (24/55), the mean recovery time is 143 days in patients with MaWC. Smoking increases the risk for MaWC (OR:8.32, 95%CI:1.36-49.99, p = 0.022). The time interval between surgery and wound complication reduces the risk for MaWC (OR:0.91, 95%CI:0.84-0.99, p = 0.028) in multivariate analysis.

CONCLUSIONS

Age, tumor site and size are risk factors for WC requiring preoperative radiotherapy. Smoking and the time interval between surgery and wound complication are risk factors for MaWC as compared with MiWC. MaWC rate (19%) are comparable to those in postoperative radiotherapy and surgery alone.

Prognostic Factors in Extremity Soft Tissue Sarcomas Treated with Radiotherapy: Systematic Review of the Literature

Soft tissue sarcomas of the extremities are rare tumors with various prognostic factors. Their management is debatable due to their inconsistent results within the literature and the lack of large prospective studies. The objective of this systematic review is to analyze the available scientific data on prognostic factors concerning the characteristics of the patients, the disease and the treatments performed, as well as their potential complications, on studies with a median follow-up of 5 years at minimum. A search of articles following the "PRISMA method" and using the PubMed search engine was conducted to select the most relevant studies. Twenty-five articles were selected, according to preestablished criteria. This review provides a better understanding of the prognosis and disease outcome of these tumors. Many factors were described comparing the frequency of occurrence according to the studies, which remain heterogeneous between them. Significant factors that could orient patients to radiotherapy were highlighted. These positive prognostic factors provide valuable insight to optimize radiotherapy treatments for patients treated for soft tissue sarcoma of the extremities.

Toxicity, normal tissue and dose-volume planning parameters for radiotherapy in soft tissue sarcoma of the extremities: A systematic review of the literature

BACKGROUND

Patients with soft tissue sarcoma of the extremities (STSE) are left with high incidence of toxicities after Radiotherapy (RT). Understanding the normal tissue dose relationship with the development of long-term toxicities may enable better RT planning in order to reduce treatment toxicities for STSE. This systematic review of the literature aims at reporting the incidence of acute and late toxicities and identifying RT delineation guidance the normal tissues structures and dose-volume parameters for STSE.

METHODS

A literature search of PUBMED-MEDLINE for studies that reported data on RT toxicity outcomes, delineation guidelines and dose-volume parameters for STSE from 2000 to 2022. Data has been tabulated and reported.

RESULTS

Thirty of 586 papers were selected after exclusion criteria. External beam RT prescriptions ranged from 30 to 72 Gy. The majority of studies reported the use of Intensity Modulated RT (IMRT) (27%). Neo-adjuvant RT was used in 40%. The highest long-term toxicities were subcutaneous and lymphoedema, reported when delivering 3DCRT. IMRT had a lower incidence of toxicities. Normal tissue outlining such as weight-bearing bones, skin and subcutaneous tissue, corridor and neurovascular bundle was recommended in 6 studies. Nine studies recommended the use of dose-volume constraints, but only one recommended evidence-based dose-volume constraints.

CONCLUSION

Although the literature is replete with toxicity reports, there is a lack of evidence-based guidance on normal tissue and dose-volume parameters and strategies to reduce the normal tissues irradiation when optimising RT plans for STSE are poor compared to other tumour sites.

Technical development and validation of a clinically applicable microenvironment classifier as a biomarker of tumour hypoxia for soft tissue sarcoma

BACKGROUND

Soft tissue sarcomas (STS) are rare, heterogeneous tumours and biomarkers are needed to inform management. We previously derived a prognostic tumour microenvironment classifier (24-gene hypoxia signature). Here, we developed/validated an assay for clinical application.

METHODS

Technical performance of targeted assays (Taqman low-density array, nanoString) was compared in 28 prospectively collected formalin-fixed, paraffin-embedded (FFPE) biopsies. The nanoString assay was biologically validated by comparing to HIF-1α/CAIX immunohistochemistry (IHC) in clinical samples. The Manchester (n = 165) and VORTEX Phase III trial (n = 203) cohorts were used for clinical validation. The primary outcome was overall survival (OS).

RESULTS

Both assays demonstrated excellent reproducibility. The nanoString assay detected upregulation of the 24-gene signature under hypoxia in vitro, and 16/24 hypoxia genes were upregulated in tumours with high CAIX expression in vivo. Patients with hypoxia-high tumours had worse OS in the Manchester (HR 3.05, 95% CI 1.54-5.19, P = 0.0005) and VORTEX (HR 2.13, 95% CI 1.19-3.77, P = 0.009) cohorts. In the combined cohort, it was independently prognostic for OS (HR 2.24, 95% CI 1.42-3.53, P = 0.00096) and associated with worse local recurrence-free survival (HR 2.17, 95% CI 1.01-4.68, P = 0.04).

CONCLUSIONS

This study comprehensively validates a microenvironment classifier befitting FFPE STS biopsies. Future uses include: (1) selecting high-risk patients for perioperative chemotherapy; and (2) biomarker-driven trials of hypoxia-targeted therapies.

Dosimetric comparison between proton beam therapy, intensity modulated radiation therapy, and 3D conformal therapy for soft tissue extremity sarcoma

PURPOSE/OBJECTIVES

Proton beam therapy (PBT) may provide a dosimetric advantage in sparing soft tissue and bone for selected patients with extremity soft sarcoma (eSTS). We compared PBT with photons plans generated using intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT).

MATERIALS/METHODS

Seventeen patients previously treated with pencil beam scanning PBT were included in this study. Of these patients, 14 treated with pre-operative 50 Gy in 25 fractions were analyzed. IMRT and 3D-CRT plans were created to compare against the original PBT plans. Dose-volume histogram (DVH) indices were evaluated amongst PBT, IMRT, and 3D plans. Kruskal-Wallis rank sum tests were used to get the statistical significance. A p value smaller than .05 was considered to be statistically significant.

RESULTS

For the clinical target volume (CTV), D2%, D95%, D98%, D_min, D_max, and V50Gy, were assessed. D_min, D1%, D_max, D_mean, V1Gy, V5Gy, and V50Gy were evaluated for the adjacent soft tissue. D1%, D_max, D_mean, and V35-50% were evaluated for bone. All plans met CTV target coverage. The PBT plans delivered less dose to soft tissue and bone. The mean dose to the soft tissue was 2 Gy, 11 Gy, and 13 Gy for PBT, IMRT, and 3D, respectively (p < .001). The mean dose to adjacent bone was 15 Gy, 26 Gy, and 28 Gy for PBT, IMRT, and 3D, respectively (p = .022).

CONCLUSION

PBT plans for selected patients with eSTS demonstrated improved sparing of circumferential soft tissue and adjacent bone compared to IMRT and 3D-CRT. Further evaluation will determine if this improved dosimetry correlates with reduced toxicity and improved quality of life.

Safety and potential increased risk of toxicity of radiotherapy combined immunotherapy strategy

Accumulating interest has emerged in exploring the toxicity profiles of the combination strategy of radiotherapy (RT) and immune checkpoint inhibitors (ICIs). Much remains unknown regarding safety and the potential increased risk of toxicity of a combined treatment. ICI prolongs survival but can induce immune-related adverse events as well. To increase awareness of adverse effect and support immediate and successful management, we go over the literature on the safety of RT combined immunotherapy strategy. Representative evidence relevant to RT combined with ICI in the brain, lung, head and neck, and pelvic malignance was reviewed respectively. Given radiation doses and fractionation, the irradiated volume, the timing of RT, and ICI would significantly affect the safety and efficiency of ICI+RT combination therapy, and no consensus had been reached about how to arrange RT delivery in the combined contexture, we went over the available literature and tried to address these challenges including the timing of RT, optimal dose and fractionations, RT target and target volume, and potential biomarkers to predict toxicity. We found even though RT+ICI combination therapy might augment toxicities, the majority of patients experienced grade 4 or 5 AE are relatively rare and no significant difference could be found between combination group and monotherapy group. Sometimes the acute toxicity with ICI is much less predictable and often life threatening and in some can give rise to permanent effects. Clinicians across disciplines should be aware of these uncommon lethal complications induced by ICI+RT. Early recognition is the key to successful treatment, reversibility of organ dysfunction, and in some cases even prevention of fatal outcome. If recognized early, managed properly, and no fatal AE occurs, the development of irAE indicates a good prognosis. It should be noted that nothing is known about potential late effects because very few studies have 5-year follow-up. The nature of irAE is the attack of activated immune cells on normal tissues. The nature of RT-induced AE is the DNA damage on normal tissue, which is related with the dose delivered and volume irradiated and the tolerance of surrounding normal tissues. The immune-modulating effect of SBRT may augment the damage on normal tissues. To maximize the antitumor immune response, 8-12 Gy/fraction is preferred when conducting RT. The available clinical evidence suggest RT of this dose/fractionated strategy combined with ICI have a tolerable AE profile, which need further validation by more clinical trials in the future. The combination strategy of RT with anti-PD1/PDL1 anti-body is supposed to be concurrent or RT followed by anti-PD1/PDL1 antibody. Although RT and ipilimumab combination sequence is controversial, ipilimumab prior to or concurrent with RT might be proper, which need more clinical validation. Under the concept of immunological dose painting, SBRT work as a trigger of immune response. It has been observed that SBRT of partially radiated tumors combined with ICI could induce similar tumor control compared with total tumor irradiation. The side effects of RT may be mitigated potentially due to the reduction of irradiated volume. The antitumor efficiency and safety profile of immunological RT dose painting+ICI deserve further investigation. Clinical predictive factors for irAE risk remain unclear, and more investigation deserves to be conducted about the irAE prediction.

Real-world clinical outcomes with daily image-guided IMRT in extremity soft tissue sarcomas

PURPOSE

We report the clinical outcomes of patients with soft tissue sarcomas (STS) arising in extremities treated with image-guided intensity modulated radiotherapy (IG-IMRT) at our institute. Local control of the tumors treated with RT was the primary end point of this study. Analyzing overall survival and long-term toxicities were the secondary objectives.

METHODS AND MATERIALS

The database of the patients with STS who received wide local excision and IG-IMRT at our institution from January 2012 to December 2020 was reviewed. Radiation was offered either preoperatively or postoperatively as part of multi-modality treatment.

RESULTS

Thirty-three consecutive patients were identified and included for analysis. Twenty-eight patients (84.8%) received postoperative adjuvant radiotherapy. Dedicated MRI simulation studies were performed in 31 patients (93.9%) in the treatment position. RapidArc IMRT technique was used in 31 patients (93.9%). A total of 2954 images were acquired during 991 treatment sessions. Errors exceeding 1 mm in the x, y and z directions were corrected online before the treatment. With a median follow-up of 36 months, two patients (6.1%) developed local recurrence. The 3-year local control was 90.9% (95% CI, 0.76 - 0.98), and the 5-year overall survival was 71.7% (95% CI, 0.44 - 0.88). One patient (3.03%) sustained a pathological fracture during the follow-up period.

CONCLUSION

Our results showed that IMRT with daily imaging offered excellent local control with acceptable long-term toxicity, as well as being feasible and practical to implement in our routine clinical practice.

Low rate of function-limiting side effects with high-dose adjuvant radiotherapy in high-grade soft tissue extremity sarcomas: a retrospective single-center analysis over 10 years

Background

Over the years, radiotherapy has been established as a tool to improve local control for high-grade sarcomas. Although the European Society for Medical Oncology guidelines has taken notice of a shift toward a neoadjuvant radiotherapy approach, the American Society for Radiation Oncology guidelines clearly favor a neoadjuvant approach, citing debilitating long-term adverse effects when radiotherapy is applied postoperatively. In this study, we examined these irradiation-associated adverse events for adjuvant radiotherapy and focused on the prognostic factors for disease outcome, including local control.

Methods

In this retrospective study, data for 106 patients with extremity soft-tissue sarcomas diagnosed between 1997 and 2021, of which 40 received adjuvant radiotherapy, were collected from the clinical and radiological information systems of a high-volume sarcoma treatment center. These data were then analyzed for radiation-associated side effects as well as predictive factors for overall survival, disease-free survival, local control, and surgical complications.

Results

Radiotherapy was beneficial to patients improving local control, especially for high-grade sarcomas, even when those were resected with negative margins. Side effects due to radiotherapy occurred in 87.5% of the patients, and these effects primarily included radiation dermatitis in 67.5%; however, only 40.0% had any adverse event of ≥ grade 2 according to Common Terminology Criteria for Adverse Events. Long-term function-limiting side effects occurred in 45.0% of the patients; 10% exhibited ≥ grade 2 function-limiting adverse events. Greater time between surgery and adjuvant radiotherapy was beneficial for the patients, whereas joint infiltrating sarcomas were associated with more severe long term, function-limiting adverse events. 28.3% of the patients experienced a recurrence at any location (median time 18.35 months) and in 16% the recurrence was local (median time 16.11 months), resulting in 1, 3, and 5 year disease-free survival rates of 74.1, 58.9, and 38.5% and local control rates of 78.7, 61.6, and 42.8% were observed, respectively.

Conclusion

Recurrences may be avoided with high-dose radiation, especially for high-grade G2 and G3 sarcomas, even after complete R0 resection. This resulted in a low rate of severe long-term function-limiting adverse events. Thus, adjuvant radiotherapy should be seriously considered when planning patient treatment, especially when treating patients that present with high-grade sarcomas.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-022-04423-1.

Preoperative hypofractionated radiotherapy for soft tissue sarcomas: a systematic review

Background

Soft tissue sarcomas (STS) represent a diverse group of rare malignant tumors. Currently, five to six weeks of preoperative radiotherapy (RT) combined with surgery constitute the mainstay of therapy for localized high-grade sarcomas (G2–G3). Growing evidence suggests that shortening preoperative RT courses by hypofractionation neither increases toxicity rates nor impairs oncological outcomes. Instead, shortening RT courses may improve therapy adherence, raise cost-effectiveness, and provide more treatment opportunities for a wider range of patients. Presumed higher rates of adverse effects and worse outcomes are concerns about hypofractionated RT (HFRT) for STS. This systematic review summarizes the current evidence on preoperative HFRT for the treatment of STS and discusses toxicity and oncological outcomes compared to normofractionated RT.

Methods

We conducted a systematic review of clinical trials describing outcomes for preoperative HFRT in the management of STS using PubMed, the Cochrane library, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Embase, and Ovid Medline. We followed the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Trials on retroperitoneal sarcomas, postoperative RT, and hyperthermia were excluded. Articles published until November 30th, 2021, were included.

Results

Initial search yielded 94 articles. After removal of duplicate and ineligible articles, 13 articles qualified for analysis. Eight phase II trials and five retrospective analyses were reviewed. Most trials applied 5 × 5 Gy preoperatively in patients with high-grade STS. HFRT courses did not show increased rates of adverse events compared to historical trials of normofractionated RT. Toxicity rates were mostly comparable or lower than in trials of normofractionated RT. Moreover, HFRT achieved comparable local control rates with shorter duration of therapy. Currently, more than 15 prospective studies on HFRT + / − chemotherapy are ongoing.

Conclusions

Retrospective data and phase II trials suggest preoperative HFRT to be a reasonable treatment modality for STS. Oncological outcomes and toxicity profiles were favorable. To date, our knowledge is mostly derived from phase II data. No randomized phase III trial comparing normofractionated and HFRT in STS has been published yet. Multiple ongoing phase II trials applying HFRT to investigate acute and late toxicity will hopefully bring forth valuable findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-022-02072-9.

Long-term experience with intraoperative electron radiation therapy boost in extremity sarcoma

BACKGROUND

In patients with extremity soft tissue sarcoma (eSTS), we describe outcomes of preoperative external beam radiation therapy (EBRT), limb-sparing surgery (LSS), and intraoperative electron radiation therapy (IOERT).

METHODS

One hundred and eighteen patients with eSTS treated between October 17, 2002 and July 28, 2021 were identified. EBRT was delivered preoperatively followed by LSS and IOERT.

RESULTS

The median follow-up was 24.9 months. The presentation was primary in 102 (94%) patients and recurrent in 6 (6%) patients. Tumor location was lower extremity in 82 (76%) patients and upper extremity in 26 (24%) patients. Stage distribution was as follows: 3 (3%) IA, 24 (22%) IB, 31 (29%) II, 24 (22%) IIIA, and 25 (23%) IIIB. Final surgical margins were negative in 96 (89%) patients. The 5-year local control, failure-free survival, and overall survival were 94%, 75%, and 64%, respectively. Univariate analysis identified age >50, lower extremity, and higher grade as significant negative prognostic factors for overall survival. Grade 3 fracture or osteoradionecrosis requiring surgical fixation, neuropathy, and lymphedema occurred in 7 (6%), 1 (1%), and 0 patients, respectively.

CONCLUSIONS

This study represents one of the largest series using preoperative EBRT, LSS, and IOERT for eSTS, with high local control and a low rate of late severe toxicity.

Is there a place for definitive radiotherapy in the treatment of unresectable soft-tissue sarcoma? A systematic review

BACKGROUND

Definitive external beam radiotherapy (EBRT) is an unusual treatment of unresectable soft-tissue sarcomas (STS). Recent technical innovations and physical advantages of particle therapies may improve results of this therapeutic option. The role of this review was to report the clinical results of photon- and particle-based EBRT in unresectable STS.

MATERIAL AND METHODS

We performed a systematic review of the literature on Pubmed database to identify studies investigating the efficacy and safety of EBRT. The primary endpoint was local control (LC) and secondary endpoints were progression-free survival (PFS), overall survival (OS) and adverse events in a subset of patients with gross disease STS.

RESULTS

We identified 29 studies involving 1409 patients (pts) evaluating photon (n = 18; 956 pts), proton (n = 1; 21 pts), carbon ion (n = 2; 152 pts), neutron (n = 7; 259 pts) or pion (n = 1; 21 pts) therapy. Definitive EBRT achieves valuable 5-year LC rates of 28-73% with photon and 52-69% with particle therapies. Most local failures (66-100%) occurred within 3 years. Long-term disease control can be achieved in a fraction of patients, with 5-year PFS and OS of 0-39% and 24.7-63%, respectively. The rate of severe adverse events was highly variable with photons, <15% in proton and carbon ion therapy, whereas 25 to 50% of patients treated with neutrons and pions presented severe AE. While a dose higher or equal 64 Gy seem to improve the prognosis, delivering a dose higher or equal 68 Gy dramatically increases severe adverse events.

CONCLUSION

Definitive EBRT with dose 64-66 Gy seems to be a safe and efficient treatment for unresectable STS. Future clinical trials should assess the potential of biomarkers of response, thus identifying patients that could benefit from local treatment.

Long-term outcomes after definitive radiotherapy with modern techniques for unresectable soft tissue sarcoma

INTRODUCTION

The use of definitive radiotherapy (dRT) in unresectable soft-tissue sarcomas (STS) is still controversial and recent data are scarce. We report clinical results of this therapeutic option.

METHODS

We retrospectively included STS patients treated between 2009 and 2020, with dRT for unresectable or with a measurable residual disease after R2 surgery. Response rate, local failure (LF), progression-free survival (PFS) and overall survival (OS) were evaluated.

RESULTS

116 patients with localized/locally advanced STS were treated from 2009 to 2020, with a median age of 71 years (range 18-92). Most tumors were deep-seated (96.6%), grade 2-3 (85.1%), located in the trunk or extremities (74.2%). Helical tomotherapy, volumetric modulated arc therapy, or stereotactic radiotherapy was performed in 39.7%, 19% and 8.6% of patients, respectively. The median equivalent dose in 2 Gy fractions (EQD2) was 60 Gy (IQR 52-65). At first follow-up, 66 (58.9%) and 25 (22%) patients had stable disease and partial response. After a median follow-up of 54.8 months (IQR 40.3-95.4), 3-year LF, PFS and OS were 43.2%, 16.6% and 34%, respectively. Median OS was 21.4 months (95%CI 14-26). The multivariate analysis identified grade 3 and AJCC T3-T4 stage to be associated with both shorter PFS and OS (all p<0.001). Macroscopically incomplete resection and EQD2 ≥64Gy were associated with better OS (p=0.016 and p=0.007). Acute and late severe adverse events occurred in 24 (19.7%) and 5 (4.3%) patients.

CONCLUSION

In unresectable STS patients, definitive modern radiotherapy is a safe and effective treatment yielding long term control in selected patients.

Early Experience Using Proton Beam Therapy for Extremity Soft Tissue Sarcoma: A Multicenter Study

Purpose

Proton beam therapy (PBT) may provide an advantage when planning well-selected patients with extremity soft tissue sarcoma (eSTS), specifically for large, anatomically challenging cases. We analyzed our early experience with PBT on toxicity and outcomes.

Materials and Methods

A retrospective study was performed for eSTS treated between June 2016 and October 2020 with pencil beam scanning PBT at 2 institutions. Diagnostic, treatment, and toxicity characteristics were gathered from baseline to last follow-up or death. Wound complications were defined as secondary operations for wound repair (debridement, drainage, skin graft, and muscle flap) or nonoperative management requiring hospitalization. Statistical analysis was performed with R software.

Results

Twenty consecutive patients with a median age 51.5 years (range, 19–78 years) were included. Median follow-up was 13.7 months (range, 1.7–48.1 months). Tumor presentation was primary (n = 17) or recurrent after prior combined modality therapy (n = 3). Tumor location was either lower extremity (n = 16) or upper extremity (n = 4). Radiation was delivered preoperatively in most patients (n = 18). Median pretreatment tumor size was 7.9 cm (range, 1.3 –30.0 cm). The 1-year locoregional control was 100%. Four patients (20%) had developed metastatic disease by end of follow-up. Maximum toxicity for acute dermatitis was grade 2 in 8 patients (40%) and grade 3 in 3 patients (15%). After preoperative radiation and surgical resection, acute wound complications occurred in 6 patients (35%). Tumor size was larger in patients with acute wound complications compared with those without (medians 16 cm, range [12–30.0 cm] vs 6.3 cm, [1.3–14.4 cm], P = .003).

Conclusion

PBT for well selected eSTS cases demonstrated excellent local control and similar acute wound complication rate comparable to historic controls. Long-term follow-up and further dosimetric analyses will provide further insight into potential advantages of PBT in this patient population.

Neoadjuvant Therapy Induces a Potent Immune Response to Sarcoma, Dominated by Myeloid and B Cells

PURPOSE

To characterize changes in the soft-tissue sarcoma (STS) tumor immune microenvironment induced by standard neoadjuvant therapy with the goal of informing neoadjuvant immunotherapy trial design.

EXPERIMENTAL DESIGN

Paired pre- and postneoadjuvant therapy specimens were retrospectively identified for 32 patients with STSs and analyzed by three modalities: multiplexed IHC, NanoString, and RNA sequencing with ImmunoPrism analysis.

RESULTS

All 32 patients, representing a variety of STS histologic subtypes, received neoadjuvant radiotherapy and 21 (66%) received chemotherapy prior to radiotherapy. The most prevalent immune cells in the tumor before neoadjuvant therapy were myeloid cells (45% of all immune cells) and B cells (37%), with T (13%) and natural killer (NK) cells (5%) also present. Neoadjuvant therapy significantly increased the total immune cells infiltrating the tumors across all histologic subtypes for patients receiving neoadjuvant radiotherapy with or without chemotherapy. An increase in the percentage of monocytes and macrophages, particularly M2 macrophages, B cells, and CD4+ T cells was observed postneoadjuvant therapy. Upregulation of genes and cytokines associated with antigen presentation was also observed, and a favorable pathologic response (≥90% necrosis postneoadjuvant therapy) was associated with an increase in monocytic infiltrate. Upregulation of the T-cell checkpoint TIM3 and downregulation of OX40 were observed posttreatment.

CONCLUSIONS

Standard neoadjuvant therapy induces both immunostimulatory and immunosuppressive effects within a complex sarcoma microenvironment dominated by myeloid and B cells. This work informs ongoing efforts to incorporate immune checkpoint inhibitors and novel immunotherapies into the neoadjuvant setting for STSs.

Radiation Therapy in Primary Soft Tissue Sarcoma of the Superficial Trunk

PURPOSE

Despite anatomical differences, truncal soft tissue sarcomas (STS) often are grouped with extremity sarcomas. We evaluated the clinical outcome of patients with truncal STS who underwent gross total resection (GTR) and radiation therapy (RT), with special emphasis on those treated with intensity modulated radiation therapy (IMRT).

METHODS

From January 1, 2001 to December 31, 2018, 64 patients received GTR and RT, where 48 patients were male, 35 patients were aged ≤ 60 years, and 48 patients had tumors ≤ 10 cm. Sixty-two tumors were high grade, 36 were in the chest wall, 7 in the abdominal wall, and 21 were paraspinal. During surgery, 7 received mesh reconstruction, and 6 received flap closure. R0 resection was achieved in 53 patients. Thirteen patients received chemotherapy.

RESULTS

With a median follow-up of 57 months, the 5-year actuarial local control (LC) was 71%. In the IMRT subset (50/64, 78%), the 5-year LC for the chest/abdominal wall was 84%, and 69% for the paraspinal subsite. Grade 2+ radiation dermatitis was seen in 21 of 64 (33%) patients, 5 of 64 (8%) developed noninfectious wound complications, 5 of 64 (8%) developed infectious wound complications, and 1 of 64 (2%) developed grade 2 chest wall pain. No additional grade 2+ late toxicity was observed.

CONCLUSIONS

Based on this study, achieving LC in truncal STS treated with GTR and RT remains challenging even with IMRT (5-year LC: 78%). While the use of IMRT was more promising for tumors of the chest/abdominal wall with 5-year LC of 84%, it was 69% for those located in the paraspinal subsite, indicating a need for further improvement.

Dosimetric Comparison of VMAT and IMRT Pre-Operative Radiotherapy for Soft Tissue Sarcoma of the Extremities

PURPOSE

Radiotherapy is a standard part of limb conserving therapy for extremity soft tissue sarcoma (STS) at high risk of recurrence. Toxicities increase with radiation dose and volume of normal tissue irradiated. This study sought to compare dosimetry of volumetric modulated arc radiotherapy (VMAT), with intensity modulated radiotherapy (IMRT) and to investigate the optimal planning technique.

METHODS AND MATERIALS

Twenty patients with extremity STS who underwent preoperative radiotherapy (50 Gy in 25 fractions) between 2016 and 2020 at a sarcoma specialist centre were included. The original treatment techniques were sliding window IMRT or 3D conformal. VMAT plans were retrospectively generated according to the original tumour and organ at risk constraints. Quality assurance was performed as per departmental protocol. Wilcoxon signed-rank test was used to compare dosimetric parameters (for planning target volume, in-field bone, and soft tissue structures), monitor units (MU) and treatment time.

RESULTS

Median patient age was 65 years and majority were male (n=14, 70%). Commonest subtype was undifferentiated pleomorphic sarcoma (n=14, 70%) and most tumours were located on the thigh (n=12, 60%). Median PTV volume was 1110 cm³ and median volume of in-field bone 236 cm³. VMAT plans had significantly lower average MU (480 vs 862 MU, p<0.001) and overall treatment time (300 vs 153 seconds, p<0.001). PTV coverage favoured VMAT, with marginally higher mean, minimum, and maximum doses, and higher Conformity Index. However, differences were not statistically significant. Dose to infield bone and soft tissue structures were similar or slightly lower with VMAT.

CONCLUSIONS

In extremity soft tissue sarcoma, VMAT plans demonstrated a favourable trend toward tumour coverage and dose conformity compared to IMRT along with significantly lower monitor units and half the overall treatment time.

Preoperative Stereotactic Body Radiation Therapy for Soft-Tissue Sarcoma: Results of Phase 2 Study

Purpose

Preoperative radiation followed by surgical resection is a standard treatment for soft-tissue sarcomas (STS). We report on 2 consecutive, phase 2, single-arm studies evaluating 5 fraction stereotactic body radiation therapy (SBRT) treatments followed by surgical resection for STS (clinical trails.gov NCT02706171).

Methods and Materials

A total of 16 patients were treated with preoperative SBRT. Tumor size in the greatest dimension was a median 6.7 cm (maximum: 14 cm) and the majority of STS were in the extremities. SBRT consisted of 35 to 40 Gy in 5 fractions every other day.

Results

Median follow-up time was 1719 days (4.7 years). Grade ≥3 acute toxicity occurred in 1 patient (grade 3 skin changes). Fifteen patients proceeded with surgical resection. Three patients had a wound complication after surgery, 1 patient had grade ≥3 late toxicity (grade 4 requiring surgical intervention). There was 1 local recurrence and 5 distant recurrences.

Conclusions

Long-term follow-up on SBRT for STS found acceptable control and toxicity rates, and warrants further evaluation.

Radiation Therapy for Treatment of Soft Tissue Sarcoma in Adults: Executive Summary of an ASTRO Clinical Practice Guideline

PURPOSE

This guideline provides evidence-based recommendations addressing the indications for radiation therapy (RT), sequencing of local therapies, and appropriate dose and planning techniques for management of primary, operable, localized, soft tissue sarcoma (STS) in adults.

METHODS

The American Society for Radiation Oncology convened a task force to address 5 key questions focused on the use of RT for management of STS. These questions included indications for RT for STS of the extremity and superficial trunk; considerations for sequencing of RT with respect to surgery, dose of RT, appropriate treatment volumes and techniques; and the role of RT in management of retroperitoneal sarcoma. Recommendations were based on a systematic literature review and created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength.

RESULTS

Multidisciplinary evaluation and decision making are recommended for all cases of STS. RT is recommended for patients in whom there is increased risk of local recurrence of resected STS, particularly if close or microscopically positive margins are anticipated or have occurred. When RT is indicated, preoperative RT is strongly recommended over postoperative RT. Postoperative RT is conditionally recommended in specific clinical circumstances (eg, uncontrolled pain or bleeding) or when the risk of wound complications outweighs that of late toxicity from RT. Routine use of RT in addition to oncologic resection for retroperitoneal sarcoma is conditionally not recommended. When RT is used for retroperitoneal sarcoma, preoperative RT is recommended, whereas postoperative RT is not recommended.

CONCLUSIONS

Based on currently published data, the American Society for Radiation Oncology task force has proposed evidence-based recommendations regarding the use of RT for STS in adults. Future studies will ascertain whether alterations in dosing and sequencing may optimize outcomes and quality of life.

Efficacy and Safety of Hypofractionated Preoperative Radiotherapy for Primary Locally Advanced Soft Tissue Sarcomas of Limbs or Trunk Wall

BACKGROUND

The use of adjuvant radiotherapy (RT) shows a significantly decreased incidence of local recurrence (LR) in soft tissue sarcomas (STS). This study aimed to assess the treatment scheme's effect in patients with primary STS treated at one institution.

METHODS

In this phase 2 trial, 311 patients aged ≥18 years with primary, locally advanced STS of the extremity or trunk wall were assigned to multimodal therapy conducted at one institution. The preoperative RT scheme consisted of 5 Gy per fraction for a total dose of 25 Gy. Surgery was performed within 2-4 days from the last day of RT. The primary endpoint was LR-free survival (LRFS). Adverse events of the treatment were assessed.

RESULTS

We included 311 patients with primary locally advanced STS. The median tumor size was 11 cm. In total, 258 patients (83%) had high-grade tumors. In 260 patients (83.6%), clear surgical margins (R0) were obtained. Ninety-six patients (30.8%) had at least one type of treatment adverse event. LR was observed in 13.8% patients. The 5-year overall survival was 63%.

CONCLUSION

In this group, with a significant percentage of patients with extensive, high-grade STS, hypofractionated preoperative RT was associated with good local control and tolerance.

The role of radiotherapy in adult soft tissues sarcoma of the extremities

Local management of adult soft tissue sarcoma of the extremities has evolved over the past decades. Until the 1970s, radical surgery (amputations) was the standard therapeutic procedure resulting in significant physical and psychological morbidity for the patients. In the present era, limb sparing surgery combined with radiotherapy represents the current standard of care for high grade and > 5 cm STSs. This approach guarantees high local control rate and function preservation. The aim of this paper is to summarize the current evidence for RT in STSs of the extremities. Outcomes, technical details (techniques, timing, dose, volumes of treatment) and the emerging role of RT in the management of oligometastatic disease will be analysed. Finally, results of the recent clinical trials testing new scenarios in RT of STSs will be described.

Postradiation Fractures after Combined Modality Treatment in Extremity Soft Tissue Sarcomas

Soft tissue sarcoma (STS) of the extremities is typically treated with limb-sparing surgery and radiation therapy; with this treatment approach, high local control rates can be achieved. However, postradiation bone fractures, fractures occurring in the prior radiation field with minimal or no trauma, are a serious late complication that occurs in 2–22% of patients who receive surgery and radiation for STS. Multiple risk factors for sustaining a postradiation fracture exist, including high radiation dose, female sex, periosteal stripping, older age, femur location, and chemotherapy administration. The treatment of these pathological fractures can be difficult, with complications including delayed union, nonunion, and infection posing particular challenges. Here, we review the mechanisms, risk factors, and treatment challenges associated with postradiation fractures in STS patients.

Radiotherapy Remains Underused in the Treatment of Soft-Tissue Sarcomas: Disparities in Practice Patterns in the United States

BACKGROUND

Practice patterns of radiation therapy (RT) use for soft-tissue sarcoma (STS) remain quite variable, despite clinical practice guidelines recommending the addition of RT to surgery for patients with high-grade STS, particularly for larger tumors. Using the National Cancer Database (NCDB), we assessed patterns of overall RT use, neoadjuvant versus adjuvant treatment, and specific RT modalities in this population.

PATIENTS AND METHODS

Patients aged ≥18 years with stage II/III STS in 2004 through 2015 were identified from the NCDB. Patterns of care were assessed using multivariable logistic regression analysis.

RESULTS

Of 27,426 total patients, 11,654 (42%) were treated with surgery alone versus 15,772 (58%) with RT in addition to surgery, with no overall increase in RT use over the study period. Notable clinical predictors of receipt of RT included tumor size (>5 cm), grade III, and tumors arising in the extremities. Conversely, female sex, older age (≥70 years), Black race, noncommercial insurance coverage, farther distance to treatment, and poor performance status were negative predictors of RT use. Of those receiving RT, 27% were treated with neoadjuvant RT and 73% with adjuvant RT. The proportion of those receiving neoadjuvant RT increased over time. Relevant factors associated with neoadjuvant RT included treatment at academic centers, larger tumor size, and extremity tumors. Of those who received RT with a modality specified as either intensity-modulated RT (IMRT) or 3D conformal RT (3DCRT), 61% were treated with IMRT and 39% with 3DCRT. The proportion of patients treated with IMRT increased over time. Relevant factors associated with IMRT use included treatment at academic centers, commercial insurance coverage, and larger and nonextremity tumors.

CONCLUSIONS

Although use of neoadjuvant RT and IMRT has increased over time, a significant number of patients with STS are not receiving adjuvant or neoadjuvant RT. Our findings also note potential sociodemographic disparities and highlight the concern that not all patients with STS are being equally considered for RT.

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.

Six-Week Interval Between Preoperative Radiation and Surgery Is Associated With Fewer Major Wound Complications in Soft Tissue Sarcoma

OBJECTIVES

A total of 30% to 40% of soft tissue sarcoma (STS) patients develop major wound complications (MWCs) after preoperative radiation (preRT). The optimal preRT-surgery interval and its association with MWCs is unknown. This study investigated whether a longer preRT-surgery interval is associated with fewer MWCs compared with historical controls.

METHODS

All patients treated by a single surgeon after preRT with limb-sparing wide resection for extremity and trunk STS were retrospectively reviewed from 2004 to 2014. The primary outcome was MWCs defined as a secondary operation, invasive procedure, wound packing, or readmission for wound care. Secondary outcomes of local recurrence and survival were followed and independent variables were analyzed for an association with MWCs.

RESULTS

Fifty-four patients were included with a median follow-up of 32 months and age of 61 years. The majority of tumors were deep (91%), large (median size of 11 cm), high grade (78%) and within the lower extremity (78%). The median preRT-surgery interval was 43 days and 80% of patients received surgery 35 to 49 days after radiation. MWCs were observed in 15% of patients and 88% occurred within 40 days. Predictors for MWCs on multivariate analysis were peripheral vascular disease (P=0.03), location in the medial compartment of the thigh (P=0.03), and neurovascular involvement (P=0.03).

CONCLUSIONS

This study presents a cohort of STS patients with an extended preRT-surgery interval of ~6 weeks. MWCs in this population occurred at a lower rate than historical controls. Overall these findings support the exploration of a longer interval to reduce MWCs and their associated morbidity.

Neoadjuvant Radiotherapy-Related Wound Morbidity in Soft Tissue Sarcoma: Perspectives for Radioprotective Agents

Historically, patients with localized soft tissue sarcomas (STS) of the extremities would undergo limb amputation. It was subsequently determined that the addition of radiation therapy (RT) delivered prior to (neoadjuvant) or after (adjuvant) a limb-sparing surgical resection yielded equivalent survival outcomes to amputation in appropriate patients. Generally, neoadjuvant radiation offers decreased volume and dose of high-intensity radiation to normal tissue and increased chance of achieving negative surgical margins-but also increases wound healing complications when compared to adjuvant radiotherapy. This review elaborates on the current neoadjuvant/adjuvant RT approaches, wound healing complications in STS, and the potential application of novel radioprotective agents to minimize radiation-induced normal tissue toxicity.

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.

How Technology Is Improving the Multidisciplinary Care of Sarcoma

Sarcomas are rare tumors but comprise a wide histologic spectrum. Advances in technology have emerged to address the biologic complexity and challenging diagnosis and treatment of this disease. The diagnostic approach to sarcomas has historically been based on morphologic features, but technologic advances in immunohistochemistry and cytogenetic/molecular testing have transformed the interdisciplinary work-up of mesenchymal neoplasms in recent years. On the therapeutic side, technologic advances in the delivery of radiation have made it a linchpin in the treatment of localized and oligometastatic sarcoma. In this review, we discuss recent advances in the pathologic diagnosis of sarcomas and discuss select sarcoma types that illustrate how newly discovered diagnostic, prognostic, and predictive biomarkers have refined existing classification schemes and substantially shaped our diagnostic approach. Such examples include conventional and epithelioid malignant peripheral nerve sheath tumors (MPNSTs), emerging entities in the group of round cell sarcomas, and other mesenchymal neoplasms with distinct cytogenetic aberrations. Recent advances in radiation oncology, including intensity-modulated, stereotactic, MRI-guided, and proton radiotherapy (RT), will be reviewed in the context of neoadjuvant or adjuvant localized soft-tissue sarcoma and oligometastatic or oligoprogressive disease. Innovations in translational research are expected to be introduced into clinical practice over the next few years and will likely continue to affect the rapidly evolving field of sarcoma diagnostics and therapy.

Multidisciplinary treatment of soft tissue sarcomas: An update

Standard treatment for soft tissue sarcoma, based on complete surgical resection with or without adjuvant radiotherapy and chemotherapy, has not substantially changed during the last several decades. Nevertheless, recent advances have contributed to considerable improvement in the management of these patients; for example, new magnetic resonance imaging sequences such as diffusion-weighted imaging and magnetic resonance imaging radiomics can better assess tumor extension and even estimate its grade. Detection of circulating genetic material (liquid biopsy) and next-generation sequencing are powerful techniques for genetic analysis, which will increase our understanding of the underlying molecular mechanisms and may reveal potential therapeutic targets. The role of chemotherapy in non-metastatic disease is still controversial, and there is a need to identify patients who really benefit from this treatment. Novel chemotherapeutic regimens have entered clinical praxis and can change the outcome of patients with metastatic disease. Advances in radiotherapy have helped decrease local adverse effects and sustain good local control of the disease. The following report provides an updated view of the diagnosis, treatment, and future perspectives on the management of patients with soft tissue sarcomas.

The survival benefit of radiotherapy in localized primary adult rhabdomyosarcoma

AIM

To evaluate the role of radiotherapy (RT) in the treatment of localized primary adult rhabdomyosarcoma (RMS).

METHODS

This retrospective study identified 62 consecutive adult patients with localized primary RMS from January 2000 and July 2016. Local failure-free survival (LFFS), distant metastasis-free survival (DMFS) and overall survival (OS) were analyzed by the Kaplan-Meier method. Multivariate Cox proportional hazards regression models were fit to assess the ability of patient characteristics to predict survival.

RESULTS

With a median follow-up of 33 months (range, 6-195 months), the 5-year LFFS, DMFS and OS of all patients were 64.0%, 50.0% and 45.0%, respectively. RT was administered to 28 patients (45.2%). Patients who received RT had a higher 5-year LFFS (81.7% vs 47.2%), 5-year DMFS (59.4% vs 43.1%) and 5-year OS (57.1% vs 34.8%) compared with patients who did not received RT. In mulitvariate analysis, RT retained significance as an independent predictor of improved LFFS [hazard ratio (HR) = 0.282; 95% confidence interval (CI), 0.095-0.838; P = 0.023], DMFS (HR = 0.289; 95% CI, 0.125-0.991; P = 0.004) and OS (HR = 0.334; 95% CI, 0.153-0.727; P = 0.006).

CONCLUSIONS

RT significantly reduced local recurrence, distant metastasis and tumor mortality compared with no radiotherapy for localized primary adult RMS.

A Phase II Trial of 5-Day Neoadjuvant Radiotherapy for Patients with High-Risk Primary Soft Tissue Sarcoma

PURPOSE

In a single-institution phase II study, we evaluated the safety of a 5-day dose-equivalent neoadjuvant radiotherapy (RT) regimen for high-risk primary soft tissue sarcoma.

PATIENTS AND METHODS

Patients received neoadjuvant RT alone (30 Gy in five fractions) to the primary tumor with standard margins. The primary endpoint was grade ≥2 late-radiation toxicity. Major wound complications, local recurrences, and distant metastases were also examined. In exploratory analysis, we evaluated germline biomarkers for wound toxicity and the effects of the study on treatment utilization.

RESULTS

Over 2 years, 52 patients were enrolled with median follow-up of 29 months. Seven of 44 evaluable patients (16%) developed grade ≥2 late toxicity. Major wound complications occurred in 16 of 50 patients (32%); a signature defined by 19 germline SNPs in miRNA-binding sites of immune and DNA damage response genes, in addition to lower extremity tumor location, demonstrated strong predictive performance for major wound complications. Compared with the preceding 2-year period, the number of patients treated with neoadjuvant RT alone at our institution increased 3-fold, with a concomitant increase in the catchment area.

CONCLUSIONS

A shorter 5-day neoadjuvant RT regimen results in favorable rates of wound complications and grade ≥2 toxicity after 2-year follow-up. Five-day RT significantly increased utilization of neoadjuvant RT at our high-volume sarcoma center. With further validation, a putative germline biomarker for wound complications may guide safer RT utilization.

Extremity Soft Tissue Sarcoma: Role of Local Control

OPINION STATEMENT

For localized extremity soft tissue sarcoma (eSTS), treatment is individualized and each patient needs to be evaluated by a multidisciplinary team at a referral sarcoma center specialized in the care of sarcoma. For a majority of patients, treatment for eSTS involves limb-salvage surgery, with or without the addition of radiation therapy. Surgery should only be performed by surgeons specifically fellowship trained in the resection of eSTS. Surgery alone may be considered for small, low-grade, and superficial tumors as long a wide (≥ 2 cm) margin can be achieved. In cases where a less than wide negative margin can be achieved, radiation therapy should be utilized to facilitate a planned close margin resection to preserve critical structures (such as nerves, blood vessels, and bone) without a significant impact on oncologic outcomes. Soft tissue sarcomas are rare, and as such patients often present following an inadvertent excision. In these situations, we recommend preoperative radiation and wide tumor bed re-excision, as rates of residual tumor can be high in this scenario. While there is large amount of evidence to support the use of radiotherapy to enhance local tumor control, the evidence to support the use of chemotherapy to enhance local tumor control is lacking, and as such cannot be recommended for all patients.

IMRiS phase II study of IMRT in limb sarcomas: Results of the pre-trial QA facility questionnaire and workshop

INTRODUCTION

Soft tissue sarcomas of the extremities (STSE) are rare malignancies. We report current UK practice for immobilisation of soft tissue sarcoma of STSE, as part of the initial study set-up within the IMRiS trial, a phase II study of intensity modulated radiotherapy (IMRT) in primary bone and soft tissue sarcoma.

METHODS

A facility questionnaire (FQ) was circulated to 29 IMRiS centres investigating the variation in immobilisation devices, planning techniques, and imaging protocols. A workshop was held to address concerns raised by centres. It focused on STSE immobilisation and patient set-up. Robustness of patient set-up at each centre was evaluated based on the following criteria: evidence of local set-up audit, calculation of margins based on set-up audit results, imaging frequency, and number of patients treated per centre per annum.

RESULTS

Twenty-seven (93%) questionnaires were returned. 30% (8/27) of responders routinely treated STSE with IMRT. The remaining 70% (19/27) had little or no experience with IMRT for STSE. Vacuum bags were the most frequent immobilisation device (9/27), followed by thermoplastic shells (7/27). Nine centres had audited their local set-up; however, only 4 had calculated margins in response to the results. Ten centres were classified as having high level of robustness.

CONCLUSIONS

Immobilisation devices and planning techniques for STSE are inconsistent across centres. Robustness of set-up is an important tool to ensure quality of results in a multicentre trial setting with such different levels of experience. The IMRiS trial Quality Assurance programme encourages centres to assess robustness of set-up through local audit and subsequent calculation of treatment margins.

IMPLICATIONS FOR PRACTICE

This is the first study that used robustness criteria to tailor QA support to individual centres.

Effect of Neoadjuvant Chemotherapy Plus Regional Hyperthermia on Long-term Outcomes Among Patients With Localized High-Risk Soft Tissue Sarcoma: The EORTC 62961-ESHO 95 Randomized Clinical Trial

Importance

Patients with soft tissue sarcoma are at risk for local recurrence and distant metastases despite optimal local treatment. Preoperative anthracycline plus ifosfamide chemotherapy improves outcome in common histological subtypes.

Objective

To analyze whether the previously reported improvement in local progression-free survival by adding regional hyperthermia to neoadjuvant chemotherapy translates into improved survival.

Design, Setting, and Participants

Open-label, phase 3 randomized clinical trial to evaluate the efficacy and toxic effects of neoadjuvant chemotherapy plus regional hyperthermia. Adult patients (age ≥18 years) with localized soft tissue sarcoma (tumor ≥5 cm, French Federation Nationale des Centers de Lutte Contre le Cancer [FNCLCC] grade 2 or 3, deep) were accrued across 9 centers (6, Germany; 1, Norway; 1, Austria; 1, United States) from July 1997 to November 2006. Follow-up ended December 2014.

Interventions

After stratification for tumor presentation and site, patients were randomly assigned to either neoadjuvant chemotherapy consisting of doxorubicin, ifosfamide, and etoposide alone, or combined with regional hyperthermia.

Main Outcomes and Measures

The primary end point was local progression-free survival. Secondary end points included treatment safety and survival, with survival defined from date of randomization to death due to disease or treatment. Patients lost to follow-up were censored at the date of their last follow-up.

Results

A total of 341 patients were randomized, and 329 (median [range] age, 51 [18-70] years; 147 women, 182 men) were eligible for the intention-to-treat analysis. By December 2014, 220 patients (67%; 95% CI, 62%-72%) had experienced disease relapse, and 188 (57%; 95% CI, 52%-62%) had died. Median follow-up was 11.3 years. Compared with neoadjuvant chemotherapy alone, adding regional hyperthermia improved local progression-free survival (hazard ratio [HR], 0.65; 95% CI, 0.49-0.86; P = .002). Patients randomized to chemotherapy plus hyperthermia had prolonged survival rates compared with those randomized to neoadjuvant chemotherapy alone (HR, 0.73; 95% CI, 0.54-0.98; P = .04) with 5-year survival of 62.7% (95% CI, 55.2%-70.1%) vs 51.3% (95% CI, 43.7%-59.0%), respectively, and 10-year survival of 52.6% (95% CI, 44.7%-60.6%) vs 42.7% (95% CI, 35.0%-50.4%).

Conclusions and Relevance

Among patients with localized high-risk soft tissue sarcoma the addition of regional hyperthermia to neoadjuvant chemotherapy resulted in increased survival, as well as local progression-free survival. For patients who are candidates for neoadjuvant treatment, adding regional hyperthermia may be warranted.

Trial Registration

clinicaltrials.gov Identifier: NCT00003052.

Current surgical strategies for treating spinal tumors: Results of a questionnaire survey among members of the German Spine Society (DWG)

PURPOSE

Questionnaire survey among the members of the German Spine Society (Deutsche Wirbelsäulen-Gesellschaft, DWG) to objectify oncological infrastructure and current standard of care in spinal tumor treatment in Germany.

METHODS

All DWG-members were contacted via the society's e-mail and asked to respond in anonymized form to a related questionnaire. Questions were asked regarding surgical specialty, type of institution involved, numbers of spinal procedures, as well as questions on treatment for primary tumors, whether the respondent belonged to a tumor center, decision-making procedures for surgery, and the type of procedure.

RESULTS

84 centers providing surgical treatment for spinal tumors in their departments were identified. 52.6% were carrying out more than 500 spinal procedures per year. There was a significant association (P ≤ 0.05) between the numbers of spinal surgeries, the number of treated tumor patients per year, the organisation in a tumor center and the treatment of primary tumors. 76% are part of a local tumor center for interdisciplinary decision making (i.e.surgical treatment and adjuvant therapy). 74% of the institutions stated that conventional postoperative radiotherapy is standardly administered in the case of secondary lesions, with 24% of them referring patients to external services for radiotherapy.

CONCLUSION

In spite of often large numbers of spinal operations, the centers perform relatively small numbers of tumor operations, particularly for primary tumors. A nearly three-quarter majority of the departments are integrated into interdisciplinary tumor care. However, there is a marked number that do not belong to an interdisciplinary organisation. Further advances in multidisciplinarity and oncology training are a continuous issue to increase treatment quality in spinal tumor patients.

Adjuvant volumetric modulated arc therapy compared to 3D conformal radiation therapy for newly diagnosed soft tissue sarcoma of the extremities: outcome and toxicity evaluation

OBJECTIVE

To assess the impact of adjuvant volumetric modulated arc therapy (VMAT) compared with three-dimensional conformal radiation therapy (3DCRT) in terms of toxicity and local control (LC) in patients with soft tissue sarcoma of the extremities.

METHODS

From 2004 to 2016, 109 patients were treated, initially using 3DCRT and subsequently with VMAT. Clinical outcome was evaluated by contrast-enhanced MRI, thoracic and abdominal CT 3 months after treatments and then every 6 months. Toxicity was evaluated with Common Terminology Criteria for Adverse Events scale v. 4.3.

RESULTS

Patients presented Stage III soft tissue sarcoma disease (77%), localized tumor (95%) at the lower extremity (87%), adipocytic histotype (46%). Surgical resection was performed in all patients, followed by adjuvant 3DCRT in 38, and VMAT in 71. The median total dose was 66 Gy/33 fractions (range 60-70 Gy;25-35 fractions). More successful bone sparing was recorded using VMAT (p < 0.001). Median follow-up was 61 months, 93 and 58 months for 3DCRT and VMAT group, respectively. The 2- and 5 year LC were 95.3±2.1%, and 87.4±3.4% for the whole cohort, 92.0±4.5%, 82.9±6.4% for 3DCRT, 97.1±2.0%, 89.6±4.1% for VMAT (p = 0.150). On univariate and multivariate analysis the factors recorded as conditioning LC were the status of the surgical resection margins (p = 0.028) and the total dose delivered (p = 0.013).

CONCLUSION

The availability of modern radiotherapy technique permit a better conformity on the target with maximum sparing of normal tissue and acceptable side-effects. VMAT is a safe and feasible treatment with limited rate of toxicity, compared to 3DCRT. Results on LC of VMAT are encouraging.

ADVANCES IN KNOWLEDGE

Soft tissue sarcoma of the extremities can benefit from the use of VMAT, with a reduction of the high dose to bones to avoid radiation osteonecrosis. An adequate total dose of at least 66 Gy and a radical surgical margin allow a good local control.

Dosimetric comparison of volumetric-arc therapy versus sliding window intensity-modulated radiotherapy in postoperative treatment for primary soft tissue sarcoma of the thigh

AIM

Intensity-modulated radiotherapy (IMRT) has demonstrated improved local control in extremity soft tissue sarcoma (STS) after limb-sparing surgery compared with three-dimensional conformal radiation therapy. Our purpose was to evaluate sliding-window IMRT (SW-IMRT) and volumetric arc therapy (VMAT) in planning target volume (PTV) coverage and dose to organs-at-risk (OAR).

METHODS

Sixteen patients undergoing postoperative RT for lower extremity STS were included. For each patient, one VMAT plan and one SW-IMRT plan were proposed. Both were evaluated using cumulative dose-volume histogram data for OAR and PTVs. Prescribed dose was 66 Gy (2 Gy/fraction) to PTV1 and 56 Gy (1.69 Gy/fraction) to PTV2. OARs contoured were femur, neurovascular bundle, minimum tissue corridor, normal tissue outside PTV2, joint and genitalia. T-Student test was performed.

RESULTS

Eleven male (69%) and five female patients (31%) were analyzed. Mean age was 60 years. Both techniques showed optimal target coverage, conformity index (CI) and homogeneity index (HI). VMAT PTV2 CI was 1.13 (mean) ± 0.08 (standard deviation) versus 1.19 ± 0.10 SW-IMRT PTV2 CI (P < 0.05). VMAT PTV1 HI was 0.09 ± 0.01 versus 0.08 ± 0.01 SW-IMRT PTV1 HI (P < 0.05). Regarding OARs, VMAT delivered lower dose to femur, genitalia, normal tissue outside PTV2 and joints. SW-IMRT spared tissue corridor mean dose (10.4 Gy ± 6.8 Gy) versus (14.7 ± 6.5 Gy) VMAT (P < 0.05).

CONCLUSIONS

Both techniques achieved great conformity, homogeneity and coverage of PTV. VMAT produced lower dose to OARS and SW-IMRT was superior in sparing dose to normal-tissue-corridor, which could reduce risk of lymphedema.

Soft tissue sarcomas of the upper extremities: Maximizing treatment opportunities and outcomes

Soft tissue sarcomas (STS) are rare tumors; they do not even equate to 1% of all malignant tumor cases. One-fifth of all STS occur in the upper extremities, where epithelioid sarcoma, synovial sarcoma, clear cell sarcoma and malignant fibrohistiocytoma are the most frequent subtypes. Surgical resection is the cornerstone of treatment. However, accomplishment of optimal oncological and functional results of STS of the upper extremities may represent a challenge for hand surgeons, due to the complex anatomy. In several cases, preoperative therapies are needed to facilitate tumor resection and improve the oncological outcome. Oligometastatic disease may also be a challenging scenario as curative strategies can be applied. Radiotherapy and chemotherapy are commonly used for this purpose albeit with conflicting evidence. Novel drug combinations have also been approved in the metastatic setting, further improving the quality of life and survival of eligible patients. Thus, prior to any approach, every case should be individually discussed in sarcoma centers with specialized multidisciplinary tumor boards. The aim of the present review was to gather the multidisciplinary experiences of the available therapeutic strategies for STS of the upper extremities.

Safety of combining radiotherapy with immune-checkpoint inhibition

Immune-checkpoint inhibitors targeting cytotoxic T- lymphocyte antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed cell death 1 ligand 1 (PD-L1) have transformed the care of patients with a wide range of advanced-stage malignancies. More than half of these patients will also have an indication for treatment with radiotherapy. The effects of both radiotherapy and immune-checkpoint inhibition (ICI) involve a complex interplay with the innate and adaptive immune systems, and accumulating evidence suggests that, under certain circumstances, the effects of radiotherapy synergize with those of ICI to augment the antitumour responses typically observed with either modality alone and thus improve clinical outcomes. However, the mechanisms by which radiotherapy and immune-checkpoint inhibitors synergistically modulate the immune response might also affect both the type and severity of treatment-related toxicities. Moreover, in patients receiving immune-checkpoint inhibitors, the development of immune-related adverse events has been linked with superior treatment responses and patient survival durations, suggesting a relationship between the antitumour and adverse autoimmune effects of these agents. In this Review, we discuss the emerging data on toxicity profiles related to immune-checkpoint inhibitors and radiotherapy, both separately and in combination, their potential mechanisms, and the approaches to managing these toxicities.

Does magnetic resonance imaging improve soft tissue sarcoma contouring for radiotherapy?

Objective:

Soft tissue sarcomas (STS) are a rare, heterogeneous tumour group. Radiotherapy improves local control. CT is used to plan radiotherapy, but has poor soft tissue definition. MRI has superior soft tissue definition. Contour variation amongst oncologists is an important factor in treatment failure. This study is the first to directly compare STS tumour contouring using CT vs MRI.

Methods:

Planning CT and T₂ weighted MR images of eight patients with STS were distributed to four oncologists. Gross tumour volume was contoured on both imaging modalities using in-house software. Images were recontoured 6 weeks later. The mean distance to agreement (DTA), standard deviation of the DTA, dice similarity coefficient (DSC) and contour volume were calculated for each oncologist and compared to a median contour volume. Results for CT and MRI were compared using a pairwise Student's t-test.

Results:

When comparing MRI to CT, tumour volumes were significantly smaller, with a difference of 21.4 cm³ across all patients (p = 0.008). There was not a statistically significant difference in the mean distance to agreement or dice similarity coefficient, but the standard deviation of the DTA showed a statistically significant improvement ( p = 0.04). For intraobserver variation, there was no statistically significant improvement using MRI vs CT.

Conclusion:

Oncologists contour smaller tumour volumes using MRI, with reduced interobserver variation. Improving the reliability and consistency of contouring is needed for improved quality assurance.

Advances in knowledge:

With further experience, the use of MRI in STS radiotherapy planning may reduce variation between oncologists and contribute to improved local control and reduced treatment toxicities.

Benefit of Radiotherapy in Extraskeletal Myxoid Chondrosarcoma: A Propensity Score Weighted Population-based Analysis of the SEER Database

OBJECTIVES

Extraskeletal myxoid chondrosarcoma (EMC) is a rare malignancy for which the role of radiotherapy is not well-defined. We examine the effect of external beam radiotherapy (EBRT) on cancer-specific survival (CSS) for patients with localized EMC, in a propensity score weighted, population-based analysis.

MATERIALS AND METHODS

The Surveillance, Epidemiology, and End Results database (1973 to 2012) was queried for cases of localized EMC arising from soft connective tissues of the trunk and extremities treated with surgery and/or EBRT. Inverse probability treatment weighting was utilized, with survival analysis by weighted Cox regression and Kaplan-Meier analysis with log-rank testing. The primary endpoint was CSS.

RESULTS

One hundred seventy-two patients were identified, diagnosed from 2004 to 2012. Ninety-four percent and 32% of 156 assessable patients underwent surgery and EBRT, respectively. By inverse probability treatment weighting, balancing covariates of age group, sex, race, grade, T stage, N stage, receipt of surgery, and anatomic site, we observed CSS of 97% versus 85% and 94% versus 85% in patients receiving EBRT versus no EBRT, at 3 and 5 years, respectively, at median follow-up of 33 months, P=0.01. A trend toward an overall survival benefit associated with EBRT was noted, P=0.06. Further adjusting for type of resection performed, CSS benefit persisted, 97% versus 85% at 3 years and 94% versus 85% at 5 years, P=0.02, with trend toward an overall survival benefit, P=0.08.

CONCLUSIONS

The receipt of EBRT is associated with a CSS benefit in localized EMC. Aggressive local therapy, including EBRT, should be considered in these patients.

Comparison of outcome and toxicity of postoperative intensity-modulated radiation therapy with two-dimensional radiotherapy in patients with soft tissue sarcoma of extremities and trunk

BACKGROUND

To compare the survival outcomes and late toxicities of postoperative intensity-modulated radiation therapy (IMRT) with two-dimensional radiotherapy (2D-RT) for patients with soft tissue sarcoma (STS) of extremities and trunk.

METHODS

274 consecutive patients with nonmetastatic STS of extremities and trunk treated with postoperative IMRT (n = 187) and 2D-RT (n = 87) were analyzed. Survival was calculated by using Kaplan-Meier method. Independent prognostic factors were identified using Cox stepwise regression analysis for variables with a P-value <0.1 in univariate analysis.

RESULTS

With a median follow-up time of 58.1 months, 30 local recurrences, 66 distant metastases, and 40 deaths occurred. Compared to 2D-RT group, the IMRT group had higher 5-year local recurrence-free survival (LRFS) (91.1% vs 80.8%; P = 0.029), distant metastasis-free survival (DMFS) (80.0% vs 69.7%; P = 0.048), disease-free survival (DFS) (75.2% vs 59.2%; P = 0.021), and overall survival (OS) (90.2% vs 81.0%; P = 0.029). Multivariate analysis showed IMRT was an independent favorable factor for LRFS, DMFS, DFS, and OS. For late toxicities, the patients in IMRT group enjoyed lower incidences of ≥Grade 2 joint stiffness (3.9% vs 12.3%; P = 0.041) and ≥Grade 3 fractures (0.0% vs 3.4%; P = 0.25) than those in 2D-RT group. ≥Grade 2 Edema was similar between these two groups (4.8% vs 9.2%; P = 0.183).

CONCLUSIONS

When compared with conventional techniques, postoperative IMRT seems to provide better LRFS, DMFS, DFS, and OS and less late toxicities in patients with STS of extremities and trunk, which should be offered as a preferred treatment.

Femoral Fracture in Primary Soft-Tissue Sarcoma of the Thigh and Groin Treated with Intensity-Modulated Radiation Therapy: Observed versus Expected Risk

PURPOSE

This study was designed to compare the observed risk of femoral fracture in primary soft-tissue sarcoma (STS) of the thigh/groin treated with intensity-modulated radiation therapy (IMRT) to expected risk calculated using the Princess Margaret Hospital (PMH) nomogram.

METHODS

Expected femoral fracture risk was calculated by using the PMH nomogram. Cumulative risk of fracture was estimated by using Kaplan-Meier statistics. Prognostic factors were assessed with univariate and multivariate analysis using Cox's stepwise regression.

RESULTS

Between February 2002 and December 2010, 92 consecutive eligible patients were assessed. Median follow-up was 73 months (106 months in surviving patients). IMRT was delivered preoperatively (50 Gy) in 13 (14%) patients and postoperatively in 79 (86%) patients (median dose, 63 Gy; range, 59.4-66.6 Gy). The observed crude risk of fractures was 6.5% compared with 25.6% expected risk from the nomogram; the cumulative risk of fracture using IMRT at 5 years was 6.7% (95% CI 2.8-16.0%). The median time to fracture was 23 months (range, 6.9-88.6). Significant predictors of fracture on univariate analysis were age ≥ 60 years (p = 0.03), tumor location in the anterior thigh (p = 0.008), and periosteal stripping to > 20 cm (p < 0.0001). On multivariate analysis, age ≥ 60 years and periosteal stripping > 20 cm retained significance (p = 0.04 and p = 0.009, respectively).

CONCLUSIONS

In this study, the cumulative risk of femur fracture in patients treated with IMRT (6.7%) is less than the expected risk using the PMH nomogram (25.6%). Established predictors of femur fracture, such as gender, tumor size, and dose of RT, seem to have less impact on fracture risk when using IMRT.

Neoadjuvant image-guided helical intensity modulated radiotherapy of extremity sarcomas - a single center experience

Background

Advanced radiotherapy (RT) techniques allow normal tissue to be spared in patients with extremity soft tissue sarcoma (STS). This work aims to evaluate toxicity and outcome after neoadjuvant image-guided radiotherapy (IGRT) as helical intensity modulated radiotherapy (IMRT) with reduced margins based on MRI-based target definition in patients with STS.

Methods

Between 2010 to 2014, 41 patients with extremity STS were treated with IGRT delivered as helical IMRT on a tomotherapy machine. The tumor site was in the upper extremity in 6 patients (15%) and lower extremity in 35 patients (85%). Reduced margins of 2.5 cm in longitudinal direction and 1.0 cm in axial direction were used to expand the MRI-defined gross tumor volume, including peritumoral edema, to the clinical target volume. An additional margin of 5 mm was added to receive the planning target volume. The full total dose of 50 Gy in 2 Gy fractions was sucessfully applied in 40 patients. Two patients received chemotherapy instead of surgery due to systemic progression. All patients were included into a strict follow-up program and were seen interdisciplinarily by the Departments of Orthopaedic Surgery and Radiation Oncology.

Results

Thirty eight patients that received total RT total dose and subsequent resection were analyzed for outcome. After a median follow-up of 38.5 months cumulative OS, local PFS and systemic PFS at 2 years were determined at 78.2, 85.2 and 54.5%, respectively. Two of 6 local recurrences were proximal marginal misses. Negative resection margins were achieved in 84% of patients. The rate of major wound complications was comparable to previous IMRT studies with 36.8%. RT was overall tolerable with low toxicity rates.

Conclusions

IMRT-IGRT offers neoadjuvant treatment for extremity STS with reduced safety margins and thus low toxicity rates. Wound complication rates were comparable to previously reported frequencies. Two reported marginal misses suggest a word of caution for reduction of longitudinal safety margins.

Electronic supplementary material

The online version of this article (10.1186/s13014-019-1207-2) contains supplementary material, which is available to authorized users.