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

The Landmark Series: Neoadjuvant Radiotherapy in Extremity Soft Tissue Sarcoma-The Way to Hypofractionation

For patients with nonmetastatic soft tissue sarcoma (STS) who are at high risk of local recurrence, the standard of care for limb-conserving local management is combined radiotherapy and surgery. Radiotherapy for STS entails 5 weeks of conventionally fractionated radiotherapy (25 × 2 Gy) preoperatively or 6 or more weeks postoperatively. There is growing interest in the use of preoperative hypofractionated regimes, viz. shorter courses with higher daily doses, for STS. Recent studies have investigated ultrahypofractionation (UHF, ≥ 5 Gy per fraction) and moderate hypofractionation (MHF, > 2 Gy but < 5 Gy per fraction) for STS. Regimens that are designed to be isoeffective for tumor control indeed result in equivalent local relapse-free survival. However, as the daily dose increases, the impacts to normal tissues and potential for toxicities increase owing to differences in fraction-size sensitivity between STS and normal tissues (e.g., skin, subcutaneous tissue, vascular structures, and bone). This article reviews the key studies informing the debate about hypofractionation for STS. We evaluate the current data that reveal relatively small patient cohorts, short follow-up time, and inconsistent toxicity reporting. A randomized, controlled investigation of conventional fractionation, MHF, and UHF is needed. The current phase 2 data confirm that any such study should have co-primary endpoints of both local relapse-free survival as well as immediate- and long-term toxicities because the fundamental question being investigated with significant increase in daily fraction size while maintaining isoeffective total dose (~ 50 Gy equivalent) is: what are the dose impacts to late-responding normal tissues that may result in decrements to physical functioning for patients?

Hypofractionated Preoperative Radiation Therapy for Soft Tissue Sarcoma: A Systematic Review

PURPOSE

Hypofractionated radiation therapy is being used more frequently for many common cancer sites. Conventionally fractionated radiation therapy treatment regimens have remained the standard of care when radiation therapy is indicated for soft tissue sarcoma (STS). The aim of this study was to systematically review published data on the use of preoperative hypofractionated radiation therapy as part of a curative treatment paradigm in patients with STS. Herein, we summarize current evidence for the use of hypofractionated radiation therapy in the preoperative treatment of STS.

METHODS AND MATERIALS

We conducted a database search for prospectively or retrospectively collected data on patients with a diagnosis of STS treated with hypofractionated radiation therapy. Studies evaluating STS of all histologic subtypes affecting extremities or trunks were included in the search. Articles were screened by 2 independent reviewers for inclusion in this review. Patient, treatment, toxicity, and outcome data were recorded and collated from selected studies.

RESULTS

Twenty-five articles are included in this review. Nine prospective trials have been published since 2020. Dose fractionations range from 25 to 40 Gy in 5 fractions or 28-42.75 Gy in 8-15 fractions. Local control and overall survival outcomes are consistent with historical data for conventionally fractionated radiation therapy. Acute toxicity and wound complication rates are in keeping with acceptable results. Late toxicity data are limited and require longer follow-up. Rates of pathologic complete response are promising across all studies.

CONCLUSIONS

There is a growing body of evidence supporting hypofractionation as safe and effective in the preoperative treatment of STS. This review highlights potential areas that could be further investigated to optimize preoperative treatment for STS.

Moderately hypofractionated, preoperative radiotherapy in patients with soft tissue sarcomas (HYPORT-STS): Updated local control, late toxicities, and patient-reported outcomes

BACKGROUND

Moderately hypofractionated, preoperative radiotherapy in patients with soft tissue sarcomas (HYPORT-STS; ClinicalTrials.gov identifier NCT03819985) investigated a radiobiologically equivalent, moderately hypofractionated course of preoperative radiotherapy (RT) 15 × 2.85 Gy in patients with soft tissue sarcoma (STS). Here, the authors report longer term follow-up to update local control and report late toxicities, as well as functional and patient-reported outcomes.

METHODS

HYPORT-STS was a single-center, open-label, single-arm, prospective phase 2 clinical trial that enrolled 120 eligible adult patients with localized STS of the extremities or superficial trunk between 2018 and 2021. Patients received a 3-week course of preoperative RT followed by surgery 4-8 weeks later. End points and follow-up were analyzed from the date of surgery.

RESULTS

The median follow-up was 43 months (interquartile range, 37-52 months), and the 4-year local recurrence-free survival rate was 93%. Overall RT-related late toxicities improved with time from local therapy (p < .001), and few patients had grade ≥2 toxicities (9%; n = 8 of 88) at 2 years. These included: 2% grade ≥2 skin toxicity, 2% fibrosis, 3% lymphedema, and 1% joint stiffness. Four patients (3%) had bone fractures. Both functional outcomes, as measured by the Musculoskeletal Tumor Society Rating Scale (p < .001), and quality of life, as measured by the Functional Assessment of Cancer Therapy-General (p < .001), improved with time from treatment, and both measures were better in follow-up at 2 years compared with baseline.

CONCLUSIONS

Long-term follow up suggests that moderately hypofractionated preoperative RT for patients with STS is safe and effective. Higher grade late toxicities affect a minority of patients. Late toxicities decrease over time, whereas functional outcomes and health-related quality of life seem to improve with more time from combined modality treatment.

Hypofractionated Preoperative Radiation Should Not Yet Be Used as Standard of Care for Extremity and Truncal Soft Tissue Sarcoma

Hypofractionated radiation therapy regimens should not be used as standard of care for localized soft tissue sarcoma.

Ultrahypofractionated Versus Normofractionated Preoperative Radiotherapy for Soft Tissue Sarcoma: A Multicenter, Prospective Real-World-Time Phase 2 Clinical Trial

Background/Objectives: The historically most commonly used preoperative radiotherapy regimen for soft tissue sarcomas (STSs) consists of 50 Gray (Gy) delivered in 25 fractions over 5 weeks, achieving excellent local control, but with significant challenges due to prolonged treatment duration and early side effects. Reducing therapy duration while maintaining optimal local and distant control would be highly beneficial for patients. We aimed to investigate the outcome of an ultrahypofractionated radiotherapy (uhRT) regimen which may represent a shorter and more patient-friendly alternative. Methods: This multi-center, open-label, phase 2 clinical trial with a clustered cohort design was conducted within the Swiss Sarcoma Network (SSN). Adult patients (aged ≥ 18 years) with STS of the extremities or superficial trunk and an Eastern Cooperative Oncology Group (ECOG) performance status of 0-3 were included. Participants were assigned to either normofractionated radiotherapy (nRT) at 50 Gy in 25 fractions or uhRT at 25 Gy in 5 fractions. Data were collected prospectively in real-world-time clinical settings. The primary outcome was local recurrence-free survival (LRFS), with overall survival (OS) and wound complications as secondary outcomes. Results: Between March 2020 and October 2023, 138 patients were included in the study; 74 received nRT and 64 received uhRT. The median follow-up times were 2.2 years for uhRT and 3.6 years for nRT. The LRFS rates at 1 year were 97.0% for nRT and 94.8% for uhRT (p = 0.57). The two-year LRFS rates were 91.9% and 94.8%, respectively (p = 0.57). The one- and two-year OS rates were 97.1%/86.3% and 98.2%/88.8%, respectively (p = 0.72). The wound complication rate was comparable between the nRT (12.0%) and uhRT (12.5%) groups (p = 0.99). Conclusions: UhRT for STSs offers an effective and safe alternative to traditional nRT, with comparable early LRFS, OS and wound complication rates. Given the two-year median follow-up, which is critical for evaluating local recurrence, uhRT shows promise as a shorter and more convenient treatment regimen. UhRT may be a safe and effective alternative treatment option to traditional nRT.

Is hypofractionated radiotherapy used to treat soft tissue sarcomas? Assessment of practices using the NETSARC network

PURPOSE

Extremity soft-tissue sarcomas are treated by wide surgical resection with normofractionated radiotherapy. Over the past 3years, several phase II trials emerged on perioperative hypofractionated radiotherapy. We aimed to review the current practice in France and Luxembourg of hypofractionated radiotherapy as curative treatment for extremity soft-tissue sarcomas.

MATERIALS AND METHODS

We sent an electronic adaptive survey to sarcoma radiation oncologists at 28 centres in France and the Grand Duchy of Luxembourg belonging to the NETSARC network. The questionnaire was distributed via the NETSARC mailing list in December 2021 and January 2022. It consisted of four to nine questions with closed multiple choice, or open-ended (short or long) answers. Some questions assessed agreement with proposals for pre- or postoperative hypofractionated radiotherapy for extremity soft-tissue sarcomas.

RESULTS

Of the 28 radiation oncologists surveyed, 11 (39.2 %) from nine centres responded. Of these, 55 % used hypofractionated radiotherapy, mainly for elderly and frail patients. The main reason why hypofractionated radiotherapy was not used was the lack of scientific evidence and therapeutic habits.

CONCLUSION

Hypofractionated radiotherapy for extremity soft-tissue sarcomas remains to be investigated in high-powered studies but could be offered in the future for well-selected patients by a multidisciplinary board in a sarcoma referral centre.

Preoperative Ultrahypofractionated Radiation Therapy for Soft Tissue Sarcomas: Low Rate of Wound Complications

Purpose

Normofractionated preoperative radiation therapy (nRT) with 50 Gy applied in 25 fractions represents the most widely used radiation therapy (RT) regimen in combined local treatment of soft tissue sarcomas (STSs). STSs are characterized by a low α/β ratio of 4 to 5 Gy, which may translate into a higher sensitivity for hypofractionation. Increasing data from cohorts and phase 2 trials on ultrahypofractionated RT (uhRT) regimens are available. We prospectively assessed our preoperative uhRT sarcoma patient cohort with a focus on short-term wound complications (WCs).

Methods and Materials

This is a prospective registry analysis of a single-center patient cohort, treated from 03.2020 to 10.2023 with uhRT (25 Gy in 5 fractions in 1 week). The same radiation oncologists (G.S./C.G.) and surgeon (B.F.) performed the treatment (61/61 and 58/60), as well as the same reference pathologist (B.B.) confirmed all histopathologic diagnoses. WC (according to CAN-NCIC-SR2 trial) and intermediate local control (LC) rates were assessed and compared with outcome data of a previously published cohort of 67 extremity/trunk sarcoma patients treated with nRT by the same authors (7% WC, 98% LC at 3 years).

Results

After a mean/median follow-up of 19/19 months (range, 0-46), LC at 1.5 years was 94%. Surgery was performed at a mean/median of 20/16 days (range, 4-60) after uhRT completion. WC were observed in 7/60 operated patients (12%), and in 5/51 (10%) extremity/trunk lesions. Early tolerance was excellent, limited to G0 to G1, even in 3 patients with prior RT to the same region. Clear resection margins were achieved in 55/60 patients (92%). Pathologic necrosis of ≥95% was reported in 5% and 75% achieved less than 50% necrosis.

Conclusions

These results show low rates of WC and high LC for uhRT and are comparable with our previously published nRT data. This study supports the routine use of preoperative uhRT for STS.

Neo-adjuvant radiation and intratumoral immunotherapy followed by surgery-NARIS trial for extremity soft tissue sarcoma

Extremity soft tissue sarcoma (ESTS) is a rare malignant nonepithelial disease, calling for combined modality treatments with surgery to further improve local control rates and long-term survival, especially in patients with multiple local recurrences with or without risk of amputation. In this double-arm, open-label, Phase II clinical trial, we will enroll 30 patients with pathologically confirmed ESTS without nodal involvement or distant metastases. Patients are randomly assigned to the combination treatment group or the radiation monotherapy group. Additionally, tumor and biological samples will be obtained directly before and after neoadjuvant therapy, allowing for studies of immune response and primary drug resistance mechanisms.Clinical Trial Registration: ChiCTR2200060659 (http://www.chictr.org.cn) (ClinicalTrials.gov).

Meta-Analysis of 5-Fraction Preoperative Radiotherapy for Soft Tissue Sarcoma

OBJECTIVES

Studies investigating preoperative 5-fraction radiation therapy (RT) for soft tissue sarcoma (STS) are limited. We performed a meta-analysis to determine the efficacy and safety of this treatment paradigm.

METHODS

This study-level meta-analysis was conducted using Bayesian methods. Statistical estimation for risk of outcome rates was conducted by posterior mean and 95% highest posterior density (HPD) intervals. Studies with 2-year local control (LC) and description of major wound complications (MWC) per the CAN-NCIC-SR2 study were included and served as the primary endpoints. Secondary endpoints included rates of acute and late toxicity. A total of 10 studies were identified and 7 met the inclusion criteria. Subgroup analyses were performed for ≥30 Gy vs <30 Gy.

RESULTS

A total of 209 patients from 7 studies were included. Five studies used ≥30 Gy (n=144), and 2 studies <30 Gy (n=64). Median follow-up was 29 months (range: 21 to 57 mo). Primary tumor location was lower extremity in 68% and upper extremity in 22%. Most tumors were intermediate or high grade (95%, 160/169), and 50% (79/158) were >10 cm. The two-year LC for the entire cohort was 96.9%, and the rate of MWC was 30.6%. There was a trend toward improved LC with ≥ 30 Gy (95% HPD: 0.95 to 0.99 vs 0.84 to 0.99). There was no difference in MWC (95% HPD: 0.18 to 0.42 vs 0.17 to 0.55) or late toxicity between the groups.

CONCLUSIONS

Preoperative 5-fraction RT for STS demonstrates excellent 2-year LC with MWC and toxicity similar to standard fractionation preoperative RT. Multi-institutional trials with a universal RT protocol are warranted.

Mesenchymal Tumor Management: Integrating Surgical and Non-Surgical Strategies in Different Clinical Scenarios

Mesenchymal tumors originate from mesenchymal cells and can be either benign or malignant, such as bone, soft tissue, and visceral sarcomas. Surgery is a cornerstone treatment in the management of mesenchymal tumors, often requiring complex procedures performed in high-volume referral centers. However, the COVID-19 pandemic has highlighted this need for alternative non-surgical approaches due to limited access to surgical resources. This review explores the role of non-surgical treatments in different clinical scenarios: for improving surgical outcomes, as a bridge to surgery, as better alternatives to surgery, and for non-curative treatment when surgery is not feasible. We discuss the effectiveness of active surveillance, cryoablation, high-intensity focused ultrasound, and other ablative techniques in managing these tumors. Additionally, we examine the use of tyrosine kinase inhibitors in gastrointestinal stromal tumors and hypofractionated radiotherapy in soft tissue sarcomas. The Sarculator tool is highlighted for its role in stratifying high-risk sarcoma patients and personalizing treatment plans. While surgery remains the mainstay of treatment, integrating advanced non-surgical strategies can enhance therapeutic possibilities and patient care, especially in specific clinical settings with limitations. A multidisciplinary approach in referral centers is vital to determine the optimal treatment course for each patient.

Modern Multidisciplinary Management of Soft Tissue Sarcoma of the Extremity and Trunk

Soft tissue sarcomas (STS) of the extremity and trunk are heterogeneous and rare tumors that require coordinated multidisciplinary management. Surgical resection remains the backbone of treatment for localized tumors, with the addition of radiotherapy to surgery to achieve high rates of local control. Despite this, overall survival is limited because of significant distant metastatic risk and a lack of efficacious systemic therapies. Clinical trials have produced conflicting results on the impact of systemic therapy in the neoadjuvant and adjuvant settings for patients with localized disease, leaving systemic treatment decisions largely guided by shared decision making and prognostic prediction tools such as nomograms. This article will review the foundational data as well as latest developments in surgical, radiotherapy, and systemic management supporting current practice guidelines for localized STS of the extremity and trunk.

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.

Are We Ready for Life in the Fast Lane? A Critical Review of Preoperative Hypofractionated Radiotherapy for Localized Soft Tissue Sarcoma

This critical review aims to summarize the relevant published data regarding hypofractionation regimens for preoperative radiation therapy (RT) prior to surgery for soft tissue sarcoma (STS) of the extremity or superficial trunk. We identified peer-reviewed publications using a PubMed search on the MeSH headings of "soft tissue sarcoma" AND "hypofractionated radiation therapy." To obtain complication data on similar anatomical radiotherapeutic scenarios we also searched "hypofractionated radiation therapy" AND "melanoma" as well as "hypofractionated radiation therapy" AND "breast cancer." We then used reference lists from relevant articles to obtain additional pertinent publications. We also incorporated relevant abstracts presented at international sarcoma meetings and relevant clinical trials as listed on the ClinicalTrials.gov website. Detailed data are presented and contextualized for ultra-hypofractionated and moderately hypofractionated regimens with respect to local control, wound complications, and amputation rates. Comparative data are also presented for late toxicities including: fibrosis, joint limitation, edema, skin integrity, and bone fracture or necrosis. These data are compared to a standard regimen of 50 Gy in 25 daily fractions delivered over 5 weeks. This analysis supports the continued use of a standard regimen for preoperative RT for STS of 25 × 2 Gy over 5 weeks without concurrent chemotherapy. Use of concurrent chemotherapy with preoperative RT for STS should be reserved for well-designed clinical trials. A randomized trial of ultra-hypofractionated and moderately hypofractionated pre op RT for STS is warranted, but it is critical for the primary endpoint (or co-primary endpoint) to be late toxicity to: bone, soft tissue, joint, and skin.

Moderate hypofractionated radiation therapy and pathologic response for soft tissue sarcomas (STS) of limbs and trunk: experience from a tertiary cancer center

BACKGROUND

Preoperative radiation therapy following by limb-sparing or conservative surgery is a standard approach for limb and trunk STS. Data supporting hypofractionated radiotherapy schedules are scarce albeit biological sensitivity of STS to radiation would justify it. We sought to evaluate the impact of moderate hypofractionation on pathologic response and its influence on oncologic outcomes.

MATERIAL AND METHODS

From October 2018 to January 2023, 18 patients with limb or trunk STS underwent preoperative radiotherapy at a median dose of 52.5 Gy (range 49.5-60 Gy) in 15 fractions of 3.5 Gy (3.3-4 Gy) with or without neoadjuvant chemotherapy. A favorable pathologic response (fPR) was considered as ≥ 90% tumor necrosis on specimen examination.

RESULTS

All patients completed planned preoperative radiotherapy. Eleven patients (61.1%) achieved a fPR, and 7 patients (36.8%) a complete pathologic response with total disappearance of tumor cells. Nine patients (47%) developed grade 1-2 acute skin toxicity, and 7 patients (38.8%) had wound complications on follow-up. With a median follow-up of 14 months (range 1-40), no cases of local relapse were observed, and actuarial 3-year overall survival (OS) and distant metastases-free survival (DMFS) are 87% and 76.4%, respectively. In the univariate analysis, the presence of a favorable pathologic response (fPR) was associated with improved 3-year OS (100% vs. 56.03%, p = 0.058) and 3-year DMFS (86.91% vs. 31.46%, p = 0.002). Moreover, both complete or partial RECIST response and radiological stabilization of the tumor lesion showed a significant association with higher rates of 3-year distant metastasis-free survival (DMFS) (83% vs. 83% vs. 56%, p < 0.001) and 3-year overall survival (OS) (100% vs. 80% vs. 0, p = 0.002).

CONCLUSIONS

Preoperative moderate hypofractionated radiation treatment for STS is feasible and well tolerated and associates encouraging rates of pathologic response that could have a favorable impact on final outcomes.

2023 Radiation oncology highlights

Radiation oncology plays an important role in the local treatment of cancers. Understanding recent advances in the application of radiation therapy to solid tumors is important for all disciplines. The radiation oncology section editors for this journal have selected the following articles for their overall significance, relevance to surgical oncologists, and to illustrate important concepts within the practice of radiation oncology.

Emerging innovations and advancements in the treatment of extremity and truncal soft tissue sarcomas

In this special edition update on soft tissue sarcomas (STS), we cover classifications, emerging technologies, prognostic tools, radiation schemas, and treatment disparities in extremity and truncal STS. We discuss the importance of enhancing local control and reducing complications, including the role of innovative imaging, surgical guidance, and hypofractionated radiation. We review advancements in systemic and immunotherapeutic treatments and introduce disparities seen in this vulnerable population that must be considered to improve overall patient care.

Meta-analysis of 5-day preoperative radiotherapy for soft tissue sarcoma (5D-PREORTS)

BACKGROUND AND PURPOSE

Although the role of conventionally fractionated radiotherapy (RT) in combination with surgery in the limb-sparing treatment of soft tissue sarcoma (STS) patients is well established, the effectiveness and safety of 5-day preoperative radiotherapy (RT) remain controversial. We performed a meta-analysis to evaluate the treatment outcomes of 5-day preoperative RT using ≥ 5 Gy per fraction with contemporary radiotherapy techniques.

MATERIALS AND METHODS

Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through March 2022 were used to identify eligible studies. Following the PRISMA and MOOSE guidelines, a meta-regression analysis was performed to assess possible correlations between variables and outcomes. A p-value < 0.05 was considered significant.

RESULTS

Nine prospective studies with 786 patients (median follow-up 35 months, 20-60 months) treated with preoperative RT delivered a median total of 30 Gy (25-40 Gy) in 5 fractions. The local control (LC), R0 margins, overall survival (OS), and distant relapse (DR) rates were 92.3% (95% CI: 87---97%), 84.5% (95% CI: 78---90%), 78% (95% CI: 70---86%), and 36% (95% CI: 70---86%). The meta-regression analysis identified a significant relationship between biological equivalent dose (BED) and larger tumor size for LC and R0 margins (p < 0.05). The subgroup analysis reveals that patients receiving BED ≥ 90 (equivalent to 30 Gy in 5 fractions) had a higher LC control rate than BED < 90 (p < 0.0001). The complete pathologic response and amputation rates were 19% (95% CI: 13-26%) and 8.3% (95% CI: 0.5-15%). Amputation rates were higher in studies using the lowest and highest doses and were related to salvage surgery after recurrence and complications, respectively. The rate of wound complication and fibrosis grade 2 or worse was 30% (95% CI 23-38%) and 6.4% (95% CI 1.9-11%).

CONCLUSION

A 5-day course of preoperative RT results in high LC and favorable R0 margins, with acceptable complication rates in most studies. Better local control and R0 margins were associated with regimens using higher BED, i.e., doses equal to or higher than 30 Gy when using 5 fractions.

Early outcomes of ultra-hypofractionated preoperative radiation therapy for soft tissue sarcoma followed by immediate surgical resection

BACKGROUND

There is increasing interest in shorter courses of radiation therapy (RT) in the management of soft tissue sarcoma (STS). We report our institutional experience for patients undergoing ultra-hypofractionated preoperative RT followed by immediate resection.

METHODS

An IRB approved review of patients treated with preoperative 5 fraction, once daily RT followed by immediate resection (within 7 days) for STS of the extremity or trunk was conducted. The primary endpoints are major wound complications and local control (LC). Secondary endpoints include grade ≥ 2 toxicity, metastasis free survival (MFS), and overall survival (OS).

RESULTS

Twenty-two patients with a median age of 67 years (range 30-87) and median follow-up of 24.5 months (IQR 17.0-35.7) met eligibility criteria; 18/22 patients (81.8 %) had ≥ 1 year follow-up. Primary tumor location was lower extremity in 15 patients (68.2 %), upper extremity in 5 (22.7 %), and trunk in 2 (9.1 %). All patients received 30 Gy in 5 fractions. The median time to resection following RT was 1 day (range 0-5). The median time from biopsy to resection was 34 days (range 20-69). Local control was 100 %; in patients with localized disease, 2-year MFS and OS were 71.3 % and 76.9 %, respectively. Major wound complications occurred in 9 patients (40.9 %), with wound complications requiring reoperation occurring in 8 patients (36.4 %). Other acute and late grade ≥ 2 toxicities were seen in 0 and 4 patients (18.2 %), respectively.

CONCLUSION

Ultra-hypofractionated preoperative RT followed by immediate resection permits expedited completion of oncologic therapy with early results demonstrating excellent local control and acceptable toxicity. Prospective data with long-term follow-up is needed.

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.