Study of Preoperative Radiotherapy for Sarcomas of the Extremities with Intensity-Modulation, Image-Guidance and Small Safety-margins (PREMISS)

Assessment of local complications with preoperative versus postoperative radiotherapy in patients with soft tissue sarcoma in extremities: A randomized comparative clinical trial

Background

Radiotherapy is considered a cornerstone as adjuvant or neo adjuvant to surgery in extremity soft tissue sarcoma (ESTS). Wound complications are the most agonizing complication that may have an impact on patient's functional outcome following radiotherapy. The best care for ESTS is by combining extensive surgical excision with safety margin and radiotherapy either preoperative (neoadjuvant) or postoperative. Preoperative radiotherapy allows for lower dose of radiation over smaller fields which is supposed to decrease long-term complications. However, several studies have shown that early complications which include wound dehiscence, infection, seroma and burn may be more frequent with preoperative radiotherapy than with postoperative radiotherapy. Most of these studies were retrospective. This study aims to prospectively assess and compare the early complications associated with radiotherapy in both techniques.

Hypothesis

Preoperative radiotherapy is not inferior to postoperative radiotherapy regarding early wound complications.

Patients and methods

Between January 2021 and June 2022, we prospectively studied 22 patients and categorized them into two groups, group A (preoperative radiotherapy) and group B (postoperative radiotherapy). We included patients with extremity soft tissue sarcoma in skeletally mature patients who were randomized into two groups with follow up 9-12 months. Wound complications, local complications, recurrence, time for wound healing and survival rate were recorded and analyzed using SPSS 25.

Results

22 patients were included, 10 in group A and 12 in group B, their mean age was 46.4 years with mean follow up 9 months. The major wound complications were higher in group A (preoperative radiotherapy). in comparison with group B (postoperative radiotherapy), however, this was not statistically significant. While other local complications were higher in group B, it was also statistically insignificant. Time for wound healing was higher in group A more than group B and was statistically significant (p value = 0.011).

Conclusion

No increase in the wound complications rate with preoperative radiotherapy by using low fractionated doses of radiotherapy and increasing interval before surgery to six weeks, although there is increased risk of delayed wound healing time after surgery. The size and site of the tumor may increase the risk of wound complications unrelated to the type of radiotherapy.

Level of evidence

II: clinical trial.

Preoperative sequential chemotherapy and hypofractionated radiotherapy combined with comprehensive surgical resection for high-risk soft tissue sarcomas: a retrospective study

Introduction

The management of soft tissue sarcomas presents considerable therapeutic challenges. This study was designed to assess the efficacy of neoadjuvant sequential chemotherapy and hypofractionated radiotherapy in conjunction with extensive surgical resection for the treatment of high-risk soft tissue sarcomas.

Materials and methods

We performed a retrospective review of 31 high-risk soft tissue sarcoma patients treated at our institution from June 2021 to June 2023. The cohort consisted of 21 males and 10 females with a mean age of 55.7 years and included both initial and recurrent disease presentations. Our treatment regimen comprised two to three cycles of neoadjuvant chemotherapy coupled with hypofractionated radiotherapy, delivered at 5 Gy per fraction to a total dose of 25-35 Gy across 5-7 days, prior to surgical resection aimed at achieving wide margins. Data collection was systematic, covering surgical outcomes, chemoradiotherapy-related complications, and prognostic factors.

Results

All patients completed the prescribed course of neoadjuvant chemoradiotherapy. 29% patients experienced grade 3+ chemotherapy toxicity, necessitating a reduction or interruption in their chemotherapy regimen. Limb preservation was accomplished in 30 patients finally. Response evaluation using RECIST 1.1 criteria post-neoadjuvant therapy revealed 9.7% with PD, 58.1% with SD, 29% with a PR, and 3.2% with a CR, culminating in an ORR of 32.2%. Postoperative complications included superficial wound infections in four patients and deep incisional infections in another four. 6 patients had developed metastasis, and 3 patients were still alive. Two experienced local recurrence. One-year DFS was 79.3%, with a one-year OS rate of 89.6%.

Conclusion

Neoadjuvant sequential chemotherapy and hypofractionated radiotherapy followed by extensive surgical resection represents an effective treatment paradigm for high-risk soft tissue sarcomas. This multimodal approach not only facilitates tumor reduction but also significantly reduces the risks of local recurrence and distant metastasis.

Brachytherapy in the Treatment of Soft-Tissue Sarcomas of the Extremities-A Current Concept and Systematic Review of the Literature

INTRODUCTION

Evidence on the use of brachytherapy in soft-tissue sarcoma (STS) is sparse. Therapy regimens are determined more by local interdisciplinary tumor conferences than by standardized protocols. Patient-specific factors complicate the standardized application of therapy protocols. The individuality of the treatment makes it difficult to compare results.

MATERIALS AND METHODS

A comprehensive literature search was conducted, whereby the literature from a period of almost 44 years (1977-2021) was graded and included in this systematic review. For this purpose, PubMed was used as the primary database. Search string included "soft-tissue sarcoma", "brachytherapy", and "extremity." Four independent researchers reviewed the literature. Only full-text articles written in English or German were included.

RESULTS

Of the 175 identified studies, 70 were eligible for analysis based on the inclusion and exclusion criteria. The key points to compare were local complications, recurrence rate and correlation with margins of resection, and the use of brachytherapy regarding tumor grading.

CONCLUSION

Brachytherapy represents an important subset of radiotherapy techniques used in STSs, whose indications and applications are constantly evolving, and for which a local control rate of 50% to 96% has been reported as monotherapy, depending on risk factors. However, the best benefit is seen in the combination of further resection and brachytherapy, and most authors at many other centers agree with this treatment strategy.

Neoadjuvant Radiation in High-Grade Soft-Tissue Sarcomas: Histopathologic Features and Response Evaluation

In this study, we sought to determine the prognostic value of both the European Organization for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group (EORTC-STBSG) score and the histologic parameters viable tumor, coagulative necrosis, hyalinization/fibrosis, and infarction in patients (n=64) with localized, nonmetastatic high-grade soft-tissue sarcomas after preoperative radiomonotherapy. A standardized macroscopic workup for pretreated surgical specimen including evaluation of a whole section of high-grade soft tissue sarcomas in the largest diameter, was used. Association with overall survival and disease-free survival was assessed. Limb salvage could be accomplished in 98.4% of patients. Overall, 90.6% tumors had negative resection margins. The median postoperative tumor diameter was 9 cm. Undifferentiated pleomorphic sarcoma (42.2%) and myxofibrosarcoma (17.2%) were the most common diagnoses. In all, 9.4% of patients had local recurrence despite clear resection margins, and 50% had distant metastases. Morphologic mapping suggests an overall heterogenous intratumoral response to radiotherapy, with significant differences among histologic subtypes. Complete regression (0% vital tumor cells) was not seen. Categorizing the results according to the proposed EORTC-STBSG 5-tier response score, <1% viable tumor cells were seen in 3.1%, ≥1% to <10% viable tumor cells in 20.4%, ≥10% to <50% viable tumor cells in 35.9% and ≥50% viable tumor cells in 40.6% of cases. Mean values for viable tumor cells were 40% (range: 1% to 100%), coagulative necrosis 5% (0% to 60%), hyalinization/fibrosis 25% (0% to 90%) and infarction 15% (0% to 79%). Hyalinization/fibrosis was a significant independent prognostic factor for overall survival (hazard ratio=4.4; P =0.047), while the other histologic parameters including the EORTC-STBSG score were not prognostic.

Ultrasound-assisted carbon ion dosimetry and range measurement using injectable polymer-shelled phase-change nanodroplets: in vitro study

Methods allowing for in situ dosimetry and range verification are essential in radiotherapy to reduce the safety margins required to account for uncertainties introduced in the entire treatment workflow. This study suggests a non-invasive dosimetry concept for carbon ion radiotherapy based on phase-change ultrasound contrast agents. Injectable nanodroplets made of a metastable perfluorobutane (PFB) liquid core, stabilized with a crosslinked poly(vinylalcohol) shell, are vaporized at physiological temperature when exposed to carbon ion radiation (C-ions), converting them into echogenic microbubbles. Nanodroplets, embedded in tissue-mimicking phantoms, are exposed at 37 °C to a 312 MeV/u clinical C-ions beam at different doses between 0.1 and 4 Gy. The evaluation of the contrast enhancement from ultrasound imaging of the phantoms, pre- and post-irradiation, reveals a significant radiation-triggered nanodroplets vaporization occurring at the C-ions Bragg peak with sub-millimeter shift reproducibility and dose dependency. The specific response of the nanodroplets to C-ions is further confirmed by varying the phantom position, the beam range, and by performing spread-out Bragg peak irradiation. The nanodroplets' response to C-ions is influenced by their concentration and is dose rate independent. These early findings show the ground-breaking potential of polymer-shelled PFB nanodroplets to enable in vivo carbon ion dosimetry and range verification.

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.

Simultaneous Integrated Boost Intensity-Modulated Radiotherapy for Locally Advanced Drug-Resistant Gastrointestinal Stromal Tumors: A Feasibility Study

Background

As an emerging clinical problem, locally advanced drug-resistant gastrointestinal stromal tumors (LADRGISTs) has relatively few therapeutic schemes. Although radiotherapy is not often considered for GISTs, it could be a valuable contributing modality. The aim of our study is to explore a safe and effective radiation regimen for LADR-GISTs.

Methods

Three patients with LADR-GISTs were treated with simultaneous integrated boost intensity-modulated radiation therapy (SIB-IMRT) plans. In the SIB-IMRT plans, gross target volume (GTV) was divided into GTV-outer, GTV-mid, and GTV-center. And the prescribed dose of planning gross target volume (PGTV) and GTV-outer were both set to 50.4 Gy in 28 fractions. GTV-mid and GTV-center were simultaneously boosted to 60–62 Gy and 62–64 Gy respectively. For comparison purposes, conventional IMRT (Con-IMRT) plans with uniform dose distribution were generated for same optimization objectives without a dose boost to GTV-mid and GTV-center. All plans were optimized to make sure that deliver at least 95% of the prescription dose was delivered to PGTV. Isodose distribution, dose profiles, conformity indexes (CIs), monitor units (MUs), and dose volume histogram (DVH) was evaluated for each individual patient. After the three patients were treated with SIB-IMRT plans, the relative changes in the tumor size and CT values by CT scanning were also tracked.

Results

Compared with Con-IMRT plans, SIB-IMRT plans saw a significant increase from D₉₅ to D₂ of the GTV. With steeper dose gradients in the dose profiles, SIB-IMRT plans had GTV-mid and GTV-center accumulated with higher dose mainly by delivering extra 93 MUs in average. However, there was no significant difference in CIs and organs at risks (OARs) DVH. The relative changes in tumor size and CT values of the three patients in follow up were up to the Choi criteria and the three patients were all assessed as partial response.

Conclusions

The proposed SIB-IMRT may be a potential technique for achieving objective response and prolonging survival of selected GISTs patients.

Pre- or postoperative radiotherapy for soft tissue sarcomas

Sarcomas are rare tumours arising from mesenchymal tissue. A multimodal management in an expert centre combining surgery and radiotherapy is the current standard of care for localized soft-tissue sarcomas of the extremities, to enable limb-sparing strategies. The delivery of pre- radiotherapy or postoperative radiotherapy offers similar local control and survival rates but the toxicity profile is quite different: preoperative radiotherapy increases the risk of wound complications and postoperative radiotherapy affects long-term functional outcomes. While postoperative radiotherapy has long been the rule, especially in Europe, technical improvements with image-guided- and intensity-modulated radiotherapy associated with a better management of postoperative wounds has tended to change practices with more frequent preoperative radiotherapy. More recently the possibilities of a hypofractionated regimen or potentiation by nanoparticles to increase the therapeutic index plead in favour of a preoperative delivery of radiotherapy. The aim of this paper is to report pros and cons of pre- and post-operative radiotherapy for soft-tissue sarcomas.

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.

A Phase 1 Pilot Study of Preoperative Radiation Therapy for Prostate Cancer: Long-Term Toxicity and Oncologic Outcomes

PURPOSE

Neoadjuvant radiation therapy (RT) improves disease control in various cancers and has become an established oncologic treatment strategy. During 2001 to 2004, we conducted a phase 1 pilot study assessing the role of short-course preoperative RT (PreORT) for men with unfavorable intermediate- and high-risk localized prostate cancer. Herein, we present long-term follow-up toxicity and oncologic outcomes.

METHODS AND MATERIALS

Eligible patients had histologically proven prostate cancer, cT1-T2N0M0 disease, prostate-specific antigen >15 to 35 ng/mL regardless of Gleason score, or prostate-specific antigen 10 to 15 ng/mL with Gleason score ≥7. Patients received 25 Gy in 5 consecutive daily fractions (5 Gy per fraction) to the prostate only, followed by radical prostatectomy within 14 days after RT completion. Primary outcomes were intraoperative morbidity and late genitourinary (GU) and gastrointestinal toxicities.

RESULTS

In total, 15 patients were enrolled; 14 patients completed PreORT followed by radical prostatectomy, which also included bilateral lymph node dissections in 13 cases. Median follow-up was 12.2 years (range, 6.7-16.3). Late GU toxicity was common, with 2 patients (13.3%) experiencing G2 toxicity and 6 patients (40%) G3 toxicity. There were no patients with G4 to G5 late GU toxicity. Late gastrointestinal toxicity was infrequent, with only 1 patient (6.7%) experiencing transient G2 proctitis. At last follow-up, 8 (53.3%) and 6 (40%) patients experienced biochemical and metastatic disease recurrence, respectively.

CONCLUSIONS

The use of PreORT in men with high-risk prostate cancer is associated with unexpected high rates of late GU toxicity. Future studies examining the role of RT preradical prostatectomy must cautiously select RT technique and dose schedule. Importantly, long-term follow-up data are essential to fully determine the therapeutic index of PreORT in the management of localized disease.

Radiotherapy in soft-tissue sarcoma of the extremities

Sarcomas are an infrequent and heterogeneous group of neoplasia. Surgery with or without associated radiotherapy (RT) is the basic treatment for this type of tumour. To increase the therapeutic ratio (the index between cytotoxic effects in tumours and normal tissue complications with a certain dose of radiation), new advances are being investigated to increase local and distant control and to decrease the morbidity of the treatment. The aim of this review was to analyse the different strategies, based on technology and biology, which are being investigated to increase the therapeutic ratio of this disease.

Radiotherapy and hyperthermia with curative intent in recurrent high risk soft tissue sarcomas

PURPOSE

Radiotherapy before or after resection is one of the pillars of treatment for localised high risk soft tissue sarcomas. Treatment intensification has been described with concurrent chemotherapy and hyperthermia. The aim of this study is to assess local control after multimodal treatment, focussing on the treatment of local recurrences after surgery only.

PATIENTS AND METHODS

Of 42 patients treated in a prospective protocol with radiotherapy and hyperthermia, nine were treated for isolated local recurrences without metastatic spread. Most patients were treated with trimodal therapy including chemotherapy with ifosfamide and underwent resection whenever possible. Median follow-up was 1.4 years.

RESULTS

The treatment was well tolerated. Estimated disease free survival, distant metastases free survival and local control for the whole cohort after 1.5 years were 66, 73 and 88%, respectively. Neoadjuvant vs. adjuvant treatment influenced local control with a trend to statistical significance. Resection status did not influence local control. The cohort of patients treated for local recurrence after surgery alone had a significantly impaired local control compared to multimodal treatment at primary diagnosis (100 vs. 52%, p < 0.001).

CONCLUSIONS

With multimodal therapy including radiotherapy and hyperthermia local tumour control is achievable even in locally recurrent tumours. The clear-cut difference of the treatment of local recurrence in contrast to primary diagnosis might either reflect difficulties in diagnosis and treatment of local recurrences or biological aggressiveness of recurrent tumours. However, we recommend to consider multimodal treatment at primary diagnosis of high risk soft tissue sarcomas.

Predictors of Wound Complications following Radiation and Surgical Resection of Soft Tissue Sarcomas

Wound complications represent a major source of morbidity in patients undergoing radiation therapy (RT) and surgical resection of soft tissue sarcomas (STS). We investigated whether factors related to RT, surgery, patient comorbidities, and tumor histopathology predict the development of wound complications. An observational study of patients who underwent STS resection and RT was performed. The primary outcome was the occurrence of any wound complication up to four months postoperatively. Significant predictors of wound complications were identified using multivariable logistic regression. Sixty-five patients representing 67 cases of STS were identified. Median age was 59 years (range 22-90) and 34 (52%) patients were female. The rates of major wound complications and any wound complications were 21% and 33%, respectively. After adjusting for radiation timing, diabetes (OR 9.6; 95% CI 1.4-64.8; P = 0.02), grade ≥2 radiation dermatitis (OR 4.8; 95% CI 1.2-19.2; P = 0.03), and the use of 3D conformal RT (OR 4.6; 95% CI 1.1-20.0; P = 0.04) were associated with an increased risk of any wound complication on multivariable analysis. These data suggest that radiation dermatitis and radiation modality are predictors of wound complications in patients with STS.