Introduction: Main oncological outcome parameters in soft tissue sarcoma (STS) patients include risk for local recurrence (LR) and distant metastasis (DM), as well as overall survival (OS). Over the past years, risk prediction tools have been developed to estimate patients’ outcome, incorporating established prognostic factors (e.g. tumour size, histological subtype) in conventional time-to-event models.
The aims of this multicenter study were to 1) assess LR and DM risk, as well as OS in a large, multicenter retrospective multinational cohort of STS patients from Austria and Switzerland, and to 2) investigate established and eventually identify novel prognostic factors for LR, DM and OS.

Methods: 746 patients with STS (mean age: 62.5±16.3 years; 49.9% males) were retrospectively included, treated for localised disease at 4 sarcoma centres. Multivariate (including age, gender, size, grading, depth, histology, location) time-to-event models (i.e. Fine&Gray models, Cox-regression models) were carried out to analyse the potential impact of variables on LR, DM, and OS.

Results: Median follow-up was 24.2 months (IQR 11.8-71.7 months). During this period, 117/596 (19.6%) and 211/619 (34.1%) patients, respectively, developed LR and DM, and 202/676 patients died (29.9%). The most common histologies were myxofibrosarcoma (n=199; 26.6%) and liposarcoma (n=165; 22.1%). The majority of tumours were high grade (n=344; 59.8%) and located in the lower limbs (n=426; 57.2%). High-grade STS were per tendency independently associated with increased LR-risk (SHR 3.13, 95%CI 0.91-10.70, p=0.069. High-grade STS (SHR 3.63, 95%CI 1.12-11.73, p=0.031) and leiomyosarcoma (SHR 3.20, 95%CI 1.14-8.98, p=0.027) showed an independent association with increased DM-risk. Advanced patient age (HR 1.06, 95%CI 1.04-1.07, p < 0.001), large tumour size (HR 1.05, 95%CI 1.02-1.08, p=0.001), and histologies UPS (HR 1.86, 95%CI 1.01-3.42, p=0.045) and “other” (HR 2.29, 95%CI 1.16-4.50, p=0.016) were independently associated with reduced OS.

Conclusion: Our preliminary findings identified similar prognostic factors as previously reported for LR, DM and OS in STS patients. Interestingly, though, some parameters (e.g. tumour size) appeared to only slightly contribute to LR- and DM-risk in this population. Future steps include refinement of the models to further enhance prognostication in patients with STS.

Introduction: Intralesional curettage is commonly used for treatment of benign bone tumours including enchondroma, chondroblastoma, and giant cell tumour of bone. This technique naturally harbours the risk of tumour cells remaining within the cavity, potentially leading to local recurrence. In order to enhance visualisation and reduce risk of remnant tumour cells, endoscopic-assisted curettage may be performed. However, a study comparing the performance of conventional and endoscopic-assisted curettage in terms of surgical time and remnant tumour cells has not been carried out thus far.
The aim of this experimental study was to assess whether endoscopy-assisted curettage is superior to conventional curettage regarding residual tumour tissue (RTT).

Methods: Within this experimental study, three orthopaedic surgeons (trainee, orthopaedic physician, orthopaedic consultant) performed both conventional (4x each) and endoscopic-assisted curettages (4x each) on specifically prepared cortical-soft cancellous lower extremity sawbone models. “Tumours” consisted of radio-opaque polyurethane-based foam injected into prepared holes at the proximal and distal ends of the femur and tibia. Pre- and postinterventional CT-scans were performed. RTT was assessed on CT-scans by an expert radiologist. For statistical analyses, percentage of RTT in relation to total lesion’s size was used. T-tests, Wilcoxon rank-sum tests, and Kruskal-Wallis tests were applied to assess differences between surgeons and surgical techniques regarding outcome. A p-value of < 0.05 was considered statistically significant.

Results: Over all lesions and locations, median RTT amounted to 1.3% (IQR 0.7%-4.1%). Significantly more RTT was present following conventional (3.5%, IQR 1.3%-5.1%) compared to endoscopy-assisted curettage (0.9%, IQR 0.5%-1.8%; p=0.024). Mean surgical time was 7.5±3.0 minutes, and significantly longer during endoscopy-assisted (9.2±2.9 minutes) compared to conventional curettage (5.9±2.0 minutes; p=0.004). Between the three surgeons, no significant difference in RTT (p=0.394) or surgical time (p=0.251) was found.

Conclusion: Our findings strength the hypothesis to use endoscopy-assisted curettage to reliably remove tumour tissue, although at expense of increased surgical time. Interestingly, no difference in RTT or surgical time depending on surgeon’s experience level was present.

Introduction: The prognosis of extremity soft tissue sarcomas (STS) is of great importance for the treatment and outcome of the patient. Nomograms are excellent prognostic tools in providing individualized estimates for disease specific survival, prognosis and guide the decisions process for treatment of STS. Aim of this study was to study the reliability and value of two nomograms as prognostic tools in patients with extremity soft tissue sarcoma (STS) treated at the University Hospital Balgrist in Zürich, Switzerland.

Methods: Patients with an extremity STS treated between 01.01.2002 – 31.12.2019 were retrospectively analyzed. Whoops lesions (R2 resections from external institutions) were excluded as were WDLPS. Statistical analysis was used to assess the nomograms accuracy.

Results: 88 Patients were eligible, with a median age of 56.1 years, median tumor size of 14.1 cm, and median follow up of 58 months. The most common tumor entity were liopsarcoma (41.1%), undifferentiated pleomorphic sarcoma (32.6%) and myxofibrosarcoma (10.5%). During the observation period a total of 41.1 % have passed away from sarcoma. The most common recurrence was observed with 43.2 % distant relapses. The median sarcoma specific survival (SSS) was 118 months. The 4 year, 8 year and 12 year overall survival OS were 66.1%, 47.3% and 47.3% respectively. The concordance indices for 5 and 10 year disease free survival (DFS) and overall survival (OS) Sarculator were 0. 681 and 0.682. The concordance indices for 4-, 8- and 12-year SSD MSKCC-Nomogram were 0. 671, 0. 667 and 0. 672.

Conclusion: Both nomograms were effective and accurate in our cohort, but both could be further improved by specifying the type of relapse and including a longer endpoint for the sarculator. The applicability of nomograms is in change, newer dynamic nomograms allow for calculating a patients prognosis during a treatment. Further investigations will have to proof their reliability and safety.

Introduction : Soft tissue sarcomas (STS) are malignant tumors that arise from skeletal and extraskeletal connective tissues at any site. In Europe, the estimated incidence averages 4-5/100 000/year in Europe - representing less than 1 percent of all newly diagnosed malignant tumor. The local management of STS is based on wide monobloc excision with negative margins in reference centers mostly combined with peri operative radiotherapy (RT). The identification of subsets of patients who do not require RT remains challenging. We proposed to investigate histologic and imaging response factors predictive of local control after preoperative RT in patients with limb or trunk wall LG and HG STS.

Methods and Materials: This is a retrospective multicenter study of nonmetastatic patients who underwent preoperative RT and surgery for limb or trunk wall STS between 2007 and 2018 in the French Sarcoma Group centers and enrolled in the "Conticabase." Patterns of local relapse were investigated taking into account the multimodal response after preoperative RT. Diagnostic and surgical samples were compared after systematic review by expert pathologists. The patients were stratified according to the grade defined by the French Federation of Cancer Centers Sarcoma Group. Log-rank tests and Cox models were used to identify prognostic factors of radiation response and local control.

Results: 257 patients were included with 17% low grade (LG) and 72.5% High Grade (HG) sarcomas. The median follow-up was 33 months. After adjusting to the location, the combination of histotype and cellularity rate significantly correlated with LR. We described 3 prognostic subgroups: from the higher risk to the lower risk: undifferentiated sarcoma (US) with cellularity rate greater than or equal to 20%, non-US (NUS) with cellularity rate greater than or equal to 20 % or US with cellularity rate < 20%, and NUS subgroup with cellularity rate < 20% or LG group.

Conclusions and perspectives : Both HG and LG tumors have different morphological and biological behaviors in response to RT. Cellularity rate greater than or equal to 20% taking into account histological subtypes could be major prognostic factors for LR. The US HG sarcomas with cellularity rate greater than or equal to 20% after preoperative RT had the higher risk of LR and specific death.

Introduction: Liquid biopsy (LB) as a non-invasive method to investigate cancer biology and monitor residual disease has gained significance in clinical practice over the years. Whilst its applicability in carcinomas is well established, the low incidence and heterogeneity of bone and soft tissue sarcomas explains the less well-established knowledge considering LB in these highly malignant mesenchymal neoplasms. However, more and more studies investigating the use of various methodologies of LB in diagnosis, prognostication, and disease monitoring of sarcoma patients are being published.

Methods: A systematic literature review in PubMed was performed according to the PRISMA guidelines, including all original English and German articles (including case reports) published until 08.02.2023 and dealing with LB in sarcoma. From initially 920 studies, 466 duplicates were removed. The resulting 454 records were screened, and 206 of these excluded based on the title. Abstracts of the remaining 248 articles underwent in-depth screening, with 68 articles ultimately included in this systematic review.

Results: The 68 articles contained evidence on use of LB in 2636 sarcoma patients. The 5 most common histological subtypes analysed were osteosarcoma (n=602; 22.8%), Ewing sarcoma (n=384; 15.0%), gastrointestinal stromal tumour (n=203; 7.7%), rhabdomyosarcoma (n=193; 7.3%) and leiomyosarcoma (n=145; 5.5%). Of the 11 liquid biopsy analytes discussed, largest evidence was present for ctDNA (26 studies), cfDNA (18 studies), miRNA (9 studies), and circulating tumour cells (7 studies).

Conclusion: This systematic literature review provides an extensive up-to-date overview about the current and potential future uses of different liquid biopsy modalities as diagnostic, prognostic, and disease monitoring markers in sarcoma.

Introduction: In soft tissue sarcomas (STS), surgery with wide margins may be preceded by neoadjuvant radiotherapy (NRTX) and/or chemotherapy (CTX). Depending on local policies, definite surgery is usually delayed 3 to 10 weeks following NRTX. Whilst early resection may be associated with higher risk for wound healing deficits and infections, late surgery may reduce the local effect of NRTX in terms of tumour control.
The aims of this literature review were to 1) systematically analyse necrosis rates following NRTX in STS, and to investigate potential associations between necrosis rates and oncological outcome parameters.

Methods: A systematic literature review adhering to the PRISMA guidelines was performed on PubMed, using specific search terms (tumor necrosis rate AND soft tissue sarcomas; soft tissue sarcoma AND radiotherapy AND necrosis; soft tissue sarcoma AND radiotherapy AND tumour necrosis). All original articles in German or English providing information on radiological and/or histopathological necrosis rate following NRTX were included.

Results: Of initially identified 2284 articles, 817 duplicates were removed. Of the remaining 1467 articles, 1381 were excluded based on their title, and 45 based on the abstract. Full texts could be retrieved in 34 of the remaining 41 articles. These original articles underwent in-depth screening, with 24 original articles finally included in this systematic review. These involved results of 1731 STS patients (52.4% males), of whom 1462 (84.5%) had received NRTX. Definite surgery was most commonly scheduled 4-6 weeks from end of NRTX (12/23 studies). Median overall histopathological necrosis rate following NRTX amounted to 41.1% (IQR 25.5 – 63.7%). Only one study discovered a potential association between a surgical delay > 7 weeks and increased necrosis rate. Altogether, 16/24 studies reported on associations between necrosis rate and oncological outcome. Increased necrosis rate associated with better distant-metastasis- or disease-free survival in 5/16 and with better overall survival in 2/16 studies. A worse association between necrosis rate and oncological outcome was reported in 3/16 studies, and 8/16 discovered no significant association.

Conclusion: According to this systematic literature review involving data of 1731 STS patients (1462 with NRTX), median necrosis rate following NRTX amounts to 41.1%. Findings on associations between necrosis rate and oncological outcome are contradictory, thoug

Background: Results after debridement and implant retention (DAIR) for early-acute periprosthetic knee joint infections (PJI) vary widely. Surgeon expertise and procedural consistency likely influence outcomes, though data are limited. We hypothesized that standardized DAIR performed by experienced surgeons dedicated to the treatment of PJI improves treatment success.

Objectives: To compare treatment outcomes of standardized DAIR performed by dedicated arthroplasty surgeons with non-standardized procedures in historical cohorts.

Methods: The EBJIS 2021 criteria were used to define PJI. All patients with early-acute PJI treated with DAIR between October 2019 and October 2022 were included. The DAIR procedures followed a predefined protocol. Treatment success was assessed using Delphi consensus criteria and compared to a historical cohort treated with non-standardized DAIR at the same center between January 2005 and May 2015 before establishment of a dedicated team for musculoskeletal infections.

Results: After exclusion, 36 patients from the present cohort were considered in the analysis and compared against the 31 TKA that underwent open DAIR in the historic cohort. Overall treatment success was achieved in 32 (88%) and 25 (80%) patients . The Chi-squared statistical test revealed no significant difference in the overall treatment success and failure rates between the historic and present cohorts (p=0.768). The subgroup analysis of the present cohort showed that 4 (11%) were treated without curative intention , while 32 (89%) underwent DAIR with curative intent. Hematogenous PJI was found in 22 (88%) cases.

Conclusions: Implementing a standardized DAIR protocol performed by surgeons from a dedicated musculoskeletal infection center resulted in better clinical outcomes for patients with periprosthetic knee joint infections, signifying a superior approach over non-standardized methods. Despite the lack of statistical significance compared to historical cohorts, the marked clinical improvements underscore the robustness and efficacy of a standardized treatment regimen.

Introduction:
Using iNPWT could potentially decrease surgical site infections by reducing wound dehiscence, improving fluid drainage, and protecting against microorganisms from entering the wound from the environment.
This study aims to assess wound healing in patients with primary closed surgical incisions following high-risk procedures (such as major limb amputations) compared to those using conventional postoperative wound dressings.
The primary outcome measure was the absence of oozing by the seventh-day post-operation.

Methods:
This prospective randomized controlled trial aims to compare the effectiveness of iNPWT with standard dry dressings in patients undergoing lower-limb amputation (including trans-femoral, trans-tibial, or trans-metatarsal procedures). Two experimented surgeons performed all amputations. Following the amputation, patients in the iNPWT group received an intra-operative application of Prevena® by 3M, maintained sterilely for seven days before being replaced by a dry dressing. Patients in the standard group received a dry sterile dressing. All surgical wounds were evaluated on the seventh-day post-operation, and the dressing stains were examined for drainage.

Results:
Between 2020 and 2022, a total of 66 patients underwent lower-limb amputation, with a mean age of 71 years (+/- 11.8), of whom 81.8% were men. The distribution of amputation included 24 trans-metatarsal, 19 trans-tibial (Burgess), and 23 trans-femoral (Gritti-Stockes) procedures. Among them, 35 received standard dry dressings, while 31 were treated with iNPWT.
After the seventh day, the iNPWT group exhibited a significant reduction in oozing compared to those treated with dry dressing only (27 out of 31 vs. 18 out of 35; p=0.0019). Furthermore, iPNWT demonstrated even greater efficacy in the trans-tibial Burgess group (8 out of 8 vs. 6 out of 11, p=0.0445). No adverse events were reported in either in each group.

Conclusions:
This randomized controlled trial demonstrates that applying iNPWT therapy postoperatively in patients undergoing major lower limb amputations significantly reduces oozing after seven days post-operation. Moreover, it appears to be even more effective in patients undergoing the trans-tibial Burgess procedure.

Introduction: Existing knowledge about Candida spondylodiscitis is primarily derived from case reports and smaller case series. This systematic review summarized all reported cases of Candida spondylodiscitis to date.

Methods: Using a PRISMA-based approach, we conducted a comprehensive search of PubMed, Web of Science, Embase, Scopus, and OVID Medline from their inception to November 30, 2022. The study was registered in PROSPERO prior to study initiation. The search syntax “albicans” AND “spondylodiscitis” was used in different variations. We included all reported cases of Candida spondylodiscitis, regardless of Candida strain or affected spinal levels. 1038 studies were identified and 72 met the inclusion criteria. Statistical analyses included Kaplan-Meier curves, Fisher's exact tests, and Wilcoxon's rank sum tests.

Results: In total, the study encompassed 89 patients (67% males) treated for Candida spondylodiscitis. The median age was 61 years, with 23% being immunocompromised and 15% identified as intravenous drug users. The median duration of antifungal treatment was six months, and fluconazole (68%) was the most frequently employed antifungal agent. The median follow-up period was 12 months. The two-year survivorship free of death was 80%, and free of revision was 94%. Younger age (p = 0.042) and a longer duration of antifungal treatment (p = 0.061) were identified as predictive factors for survival.

Conclusion: The majority of individuals affected by Candida spondylodiscitis were males in their sixties. Importantly, one in four patients was immunocompromised. One in five patients died within two years of diagnosis.