Resection Of Soft Tissue Sarcoma Research Articles

What is the Optimal Treatment Strategy after Sarcoma R2 Surgery?

Soft tissue sarcomas (STS) are rare tumours of mesenchymal origin, most commonly occurring in the extremity but also in the retroperitoneum. The curative treatment for STS is radical surgery with wide margins, in some cases in combination with perioperative radiotherapy and chemotherapy. Nonradical resection (R2) of STS has been an emerging issue in recent decades, as optimal subsequent management remains debatable. Similarly, there is still no consensus on optimal surgical margins. Combining multiple treatment modalities in adjuvant therapy can achieve local and distant control in patients following surgery with positive margins. Patients who have undergone nonradical resection therefore require additional surgical interventions, and adjuvant radiotherapy resulting in a better prognosis but a higher number of complications. Following non-radical treatment, patients with limb and trunk wall sarcomas and retroperitoneal sarcomas should also undergo increased oncological surveillance. Given the potential issues that may emerge in such clinical situations, it is crucial to up-date the current guidelines to enhance the long-term prognosis of these patients.

Development and validation of a nomogram to predict surgical site infection after soft-tissue sarcoma resection.

Surgical site infection (SSI) after soft-tissue sarcoma (STS) resection is a serious complication. The purpose of this retrospective study was to investigate the risk factors for SSI after STS resection, and to develop a nomogram that allows patient-specific risk assessment. A total of 547 patients with STS who underwent tumour resection between 2005 and 2021 were divided into a development cohort and a validation cohort. In the development cohort of 402 patients, the least absolute shrinkage and selection operator (LASSO) regression model was used to screen possible risk factors of SSI. To select risk factors and construct the prediction nomogram, multivariate logistic regression was used. The predictive power of the nomogram was evaluated by receiver operating curve (ROC) analysis in the validation cohort of 145 patients. LASSO regression analysis selected possible risk factors for SSI, including age, diabetes, operating time, skin graft or flap, resected tumour size, smoking, and radiation therapy. Multivariate analysis revealed that age, diabetes, smoking during the previous year, operating time, and radiation therapy were independent risk factors for SSI. A nomogram was developed based on the results of multivariate logistic regression analysis. In the development cohort, the incidence of SSI was 4.5% in the low-risk group (risk score < 6.89) and 26.6% in the high-risk group (risk score ≥ 6.89; p < 0.001). In the validation cohort, the incidence of SSI was 2.0% in the low-risk group and 15.9% in the high-risk group (p = 0.004). Our nomogram will enable surgeons to assess the risk of SSI in patients with STS. In patients with high risk of SSI, frequent monitoring and aggressive interventions should be considered to prevent this.

P33. When to Skip the Ladder and Take the Elevator: Complex Reconstructions Predict Reduced Complication Rates Compared To Simpler Techniques after Resection of Soft Tissue Sarcomas Located in the Thigh

P33. When to Skip the Ladder and Take the Elevator: Complex Reconstructions Predict Reduced Complication Rates Compared To Simpler Techniques after Resection of Soft Tissue Sarcomas Located in the Thigh

P38. Reconstruction Distal To Ankle after Soft Tissue Sarcoma Resection

P38. Reconstruction Distal To Ankle after Soft Tissue Sarcoma Resection

The role of free flap reconstruction after resection of extremity and trunk soft tissue sarcomas. Results of two referral centers in Argentina

IntroductionFor patients affected by extremity or trunk soft-tissue sarcomas (STS) large resections might be needed to achieve negative margins. This is a common scenario especially in locally advanced or recurrent tumors often within a pre-irradiated field. The objective of this study was to evaluate the results of free-flap reconstructions (FFR) after sarcoma surgery. ObjectiveThe endpoints were surgical results, quality of surgical margins and oncological outcome. MethodsRetrospective analysis of patients with extremity and trunk STS with free-flap reconstruction between 2008 and 2022. Demographic and tumor data, perioperative treatment, margin status, morbidity and evolution were evaluated. ResultsOf 467 patients, 25 (5.35%) required 26 free-flap reconstructions. Surgery was performed on an irradiated field in 8 (32%) patients. Reconstructions were mostly needed for distal lower extremity resections and the most common type of flap used was antero-lateral tight (ALT) flap. No R2 resections were performed. R0 and R1 resections were achieved in 22 (84.6%) and 4 (15.4%), respectively. All R1 resections were preplanned positive along a preserved critical structure. Surgical morbidity rate was 26% (7/26) and the re-operation rate was 15% (4/26) with 7.7% flap losses (2/26). At a median follow-up of 38 months, 7 (28%) patients presented local recurrences. ConclusionIn a referral sarcoma center, having a multidisciplinary surgical team capable of complex resections and reconstructions is of utmost importance for a correct and integral surgical planning. This allows optimal oncologic resections with acceptable morbidity.

When to ditch the ladder and take the elevator: The Anderson SArcoma Risk of Complications (A-SARC) score to guide reconstructive decision-making in extremity soft tissue sarcoma patients.

The reconstructive ladder relies mostly on defect size and depth to determine reconstructive technique, however, in actuality, many more variables ultimately inform reconstructive decision making, especially regarding extremity soft tissue sarcoma (eSTS) defects. The purpose of this study was to describe eSTS patients who will most optimally benefit from an advanced method of reconstruction (defined as a pedicled regional flap or free flap) and to create a simple risk assessment scale that can be employed in clinical practice. A single-institution retrospective cohort study examined patients undergoing resection of soft tissue sarcoma affecting the upper or lower extremities between 2016 and 2021. We categorized patients who required a pedicled or free flap as having had advanced reconstruction, and all other techniques were considered simple reconstruction. A regression was used to create a risk scale to guide reconstructive decision-making. The following variables were identified as independent predictors of complications and used to create our risk scale: lower extremity tumor location, preoperative radiotherapy, tumor bed excision, male sex, hypertension, and tumor volume. Intermediate and high-risk patients reconstructed using simple techniques had significantly greater overall complication rates compared to those reconstructed with advanced techniques. Major complications were significantly greater in low-risk patients reconstructed with advanced techniques. To minimize postoperative wound complications, low-risk patients should receive simple methods of reconstruction, whereas high-risk patients should be reconstructed using advanced techniques.

SP28. When To Skip The Ladder And Take The Elevator: Complex Reconstructions May Yield A More Reliable Outcome When Reconstructing Defects After Resection Of Soft Tissue Sarcomas Located In The Thigh

SP28. When To Skip The Ladder And Take The Elevator: Complex Reconstructions May Yield A More Reliable Outcome When Reconstructing Defects After Resection Of Soft Tissue Sarcomas Located In The Thigh

ASO Visual Abstract: High Community-Level Social Vulnerability is Associated with Worse Recurrence-Free Survival Following Resection of Extremity and Truncal Soft-Tissue Sarcoma.

ASO Visual Abstract: High Community-Level Social Vulnerability is Associated with Worse Recurrence-Free Survival Following Resection of Extremity and Truncal Soft-Tissue Sarcoma.

Multimodality therapy and innovative surgical techniques for successful resection and reconstruction of a rare and aggressive pleomorphic liposarcoma

Managing rare thoracic liposarcomas, accounting for < 1% of soft tissue sarcomas, demands tailored strategies. We explore effective approaches, considering tumor attributes and innovative techniques, and compare NCCN-guided therapies and surgeries. Using PubMed, Embase, and Cochrane Library, we identified studies on thoracic liposarcomas. Data synthesis summarized findings, acknowledging rarity's evidence limitations. This study reports a successful resection of a rare thoracic soft tissue sarcoma. Overcoming challenges through innovative techniques like hyperthermic pleural lavage and Gore-Tex® reconstruction, it underscores neoadjuvant therapies and surgical precision. Thoracic liposarcoma management demands tailored multidisciplinary approaches. Neoadjuvant chemotherapy, surgery, and adjuvant therapies are fundamental. Surgical ingenuity, like extrapleural pneumonectomy and novel reconstructions, ensures thorough tumor removal with minimal complications. Hyperthermic pleural lavage and Gore-Tex® offer promising refinements. Successful outcomes highlight potential for improved prognoses. Further research will optimize strategies for this rare, aggressive cancer.

Managing suspected myasthenia gravis and myositis induced by pembrolizumab in a Jehovah's Witness sarcoma patient.

Immune checkpoint inhibitors (ICIs) can cause a spectrum of adverse events known as immune-related adverse events (irAEs) that resemble autoimmune responses. Immune-mediated myasthenia gravis (MG) is a rare and serious neurologic adverse event that has been associated with ICIs requiring prompt treatment. In the Jehovah's Witness population, typical management of these adverse events may not be options, and alternative treatment choices would be needed. 73-year-old Jehovah's Witness patient with high-grade undifferentiated pleiomorphic sarcoma who developed immune-mediated MG approximately 4 weeks after initiation of pembrolizumab. On the day of admission, the patient presented with a three-day history of worsening ptosis, right greater than left. He was later found to be seronegative for MG. The patient required therapy with pyridostigmine, steroids, and agreed to plasma exchange (PLEX) prior to discharge. He achieved near resolution of his neurologic symptoms, and pembrolizumab was discontinued. He later underwent radical resection of the left thigh soft tissue sarcoma and superficial inguinal lymph node dissection. He is now on active surveillance. While neurologic adverse events typically present 6 weeks after initiation of ICIs, MG has been reported occurring as early as 4 weeks after initiation. This rare and serious adverse event requires prompt treatment, and clinicians need to be aware of the alternative treatment options in this unique patient population. Early conversations regarding blood products and factions must be had to develop a treatment plan in accordance with the patient's personal decisions.

CORR Insights®: Do Patients Treated With an Unplanned Resection for Small Superficial Soft Tissue Sarcomas Have Worse Long-term Survival Than Those Initially Treated With an Oncologic Resection?

CORR Insights®: Do Patients Treated With an Unplanned Resection for Small Superficial Soft Tissue Sarcomas Have Worse Long-term Survival Than Those Initially Treated With an Oncologic Resection?

Benefits of Collaboration Between the Wound, Ostomy, and Continence Nurse and Orthopedic Surgeon When Treating Skin Defects After Soft Tissue Sarcoma Resection: A Retrospective Case-Control Study.

The purpose of this study was to evaluate the benefits of collaborative management between orthopedic surgery and WOC nurses in patients undergoing resection of subcutaneous sarcomas. Retrospective case-control study. The sample comprised 25 patients who underwent wide resection for soft tissue sarcoma, followed by 2-stage split-thickness skin grafting. Data collection occurred between January 2015 and April 2021 in a university hospital based in Kagoshima, Japan. For comparison, we categorized these patients into 2 groups: intervention group participants were managed by an orthopedic surgeon and a WOC nurse; nonintervention group members were managed without WOC nurse participation. Patient background and treatment-related information was retrospectively collected from medical records and compared between the WOC nurse intervention group and the nonintervention group, including maximum tumor diameter, surgical time, maximum skin defect diameter, length of hospital stay, and time from surgery to complete wound healing. The average length of hospital stay was significantly shorter in the WOC nurse intervention group compared with the nonintervention group (38.3 days, SD = 8.0 vs 47.1 days, SD = 10.2; P = .023). Collaborative wound management with a WOC nurse resulted in a shorter hospital length of stay when compared to traditional management with WOC nurse involvement. Based on these findings, we assert that WOC nurses provide an important bridge between postoperative wound management in patients undergoing resection of subcutaneous sarcomas.

High Community-Level Social Vulnerability is Associated with Worse Recurrence-Free Survival (RFS) After Resection of Extremity and Truncal Soft Tissue Sarcoma.

Although social vulnerability has been associated with worse postoperative and oncologic outcomes in other cancer types, these effects have not been characterized in patients with soft tissue sarcoma. This study evaluated the association of social vulnerability and oncologic outcomes. The authors conducted a single-institution cohort study of adult patients with primary and locally recurrent extremity or truncal soft tissue sarcoma undergoing resection between January 2016 and December 2021. The social vulnerability index (SVI) was measured on a low (SVI 1-39%, least vulnerable) to high (60-100%, most vulnerable) SVI scale. The association of SVI with overall survival (OS) and recurrence-free survival (RFS) was evaluated by Kaplan-Meier analysis and Cox proportional hazard regression. The study identified 577 patients. The median SVI was 44 (interquartile range [IQR], 19-67), with 195 patients categorized as high SVI and 265 patients as low SVI. The median age, tumor size, histologic subtype, grade, comorbidities, stage, follow-up time, and perioperative chemotherapy and radiation utilization were similar between the high and low SVI cohorts. The patients with high SVI had worse OS (p = 0.07) and RFS (p = 0.016) than the patients with low SVI. High SVI was independently associated with shorter RFS in the multivariate analysis (hazard ratio, 1.64; 95% confidence interval, 1.06-2.54) but not with OS (HR, 1.47; 95% CI 0.84-2.56). High community-level social vulnerability appears to be independently associated with worse RFS for patients undergoing resection of extremity and truncal soft tissue sarcoma. The effect of patient and community-level social risk factors should be considered in the treatment of patients with extremity sarcoma.

Toward the use of diffuse reflection spectroscopy for intra-operative tissue discrimination during sarcoma surgery.

Accurately distinguishing tumor tissue from normal tissue is crucial to achieve complete resections during soft tissue sarcoma (STS) surgery while preserving critical structures. Incomplete tumor resections are associated with an increased risk of local recurrence and worse patient prognosis. We evaluate the performance of diffuse reflectance spectroscopy (DRS) to distinguish tumor tissue from healthy tissue in STSs. DRS spectra were acquired from different tissue types on multiple locations in 20 freshly excised sarcoma specimens. A -nearest neighbors classification model was trained to predict the tissue types of the measured locations, using binary and multiclass approaches. Tumor tissue could be distinguished from healthy tissue with a classification accuracy of 0.90, sensitivity of 0.88, and specificity of 0.93 when well-differentiated liposarcomas were included. Excluding this subtype, the classification performance increased to an accuracy of 0.93, sensitivity of 0.94, and specificity of 0.93. The developed model showed a consistent performance over different histological subtypes and tumor locations. Automatic tissue discrimination using DRS enables real-time intra-operative guidance, contributing to more accurate STS resections.

Explainable Model Using Shapley Additive Explanations Approach on Wound Infection after Wide Soft Tissue Sarcoma Resection: "Big Data" Analysis Based on Health Insurance Review and Assessment Service Hub.

Background and Objectives: Soft tissue sarcomas represent a heterogeneous group of malignant mesenchymal tissues. Despite their low prevalence, soft tissue sarcomas present clinical challenges for orthopedic surgeons owing to their aggressive nature, and perioperative wound infections. However, the low prevalence of soft tissue sarcomas has hindered the availability of large-scale studies. This study aimed to analyze wound infections after wide resection in patients with soft tissue sarcomas by employing big data analytics from the Hub of the Health Insurance Review and Assessment Service (HIRA). Materials and Methods: Patients who underwent wide excision of soft tissue sarcomas between 2010 and 2021 were included. Data were collected from the HIRA database of approximately 50 million individuals' information in the Republic of Korea. The data collected included demographic information, diagnoses, prescribed medications, and surgical procedures. Random forest has been used to analyze the major associated determinants. A total of 10,906 observations with complete data were divided into training and validation sets in an 80:20 ratio (8773 vs. 2193 cases). Random forest permutation importance was employed to identify the major predictors of infection and Shapley Additive Explanations (SHAP) values were derived to analyze the directions of associations with predictors. Results: A total of 10,969 patients who underwent wide excision of soft tissue sarcomas were included. Among the study population, 886 (8.08%) patients had post-operative infections requiring surgery. The overall transfusion rate for wide excision was 20.67% (2267 patients). Risk factors among the comorbidities of each patient with wound infection were analyzed and dependence plots of individual features were visualized. The transfusion dependence plot reveals a distinctive pattern, with SHAP values displaying a negative trend for individuals without blood transfusions and a positive trend for those who received blood transfusions, emphasizing the substantial impact of blood transfusions on the likelihood of wound infection. Conclusions: Using the machine learning random forest model and the SHAP values, the perioperative transfusion, male sex, old age, and low SES were important features of wound infection in soft-tissue sarcoma patients.

Outcomes and complications of postoperative seroma cavities following soft-tissue sarcoma resection.

Seroma development is a known complication following extremity and trunk soft-tissue sarcoma (STS) resection. The purpose of this study is to evaluate and characterize seroma outcomes and the development of associated complications. A retrospective review of 123 patients who developed postoperative seromas following STS resection at a single institution was performed. Various patient and surgical factors were analyzed to determine their effect on overall seroma outcomes. 77/123 seromas (62.6%) were uncomplicated, 30/123 (24.4%) developed infection, and 16/123 (13.0%) were symptomatic and required aspiration or drainage for symptom relief at an average of 12.2 months postoperatively. 65/123 (52.8%) seromas resolved spontaneously at an average time of 12.41 months. Seromas in the lower extremity (p=0.028), surgical resection volume >864 cm3, (p=<0.001) and initial seroma volume >42 cm3 (p=<0.001) increased the likelihood of infection. 90% of infected seromas developed the infection within the first three months following initial resection. No seromas which were aspirated or drained ultimately developed an infection following these procedures, though 50% recurred. Most seromas following STS resection are uncomplicated and do not require intervention, though a large resection cavity >864 cm3 and a large seroma volume >42 cm3 are risk factors for complications.

Do Patients Treated With an Unplanned Resection for Small Superficial Soft Tissue Sarcomas Have Worse Long-term Survival Than Those Initially Treated With an Oncologic Resection?

Histologic grade, size, and depth are well-known prognostic factors in soft tissue sarcomas (STS). Small (< 5 cm) and superficial STS generally have an excellent prognosis when treated with appropriate surgery. However, they are often misdiagnosed and mistreated. We reported that in midterm follow-up (5 to 7 years), patients with unplanned resections of tumors with positive margins who immediately underwent a reoperation with margin-widening re-resection and postoperative radiotherapy had survival comparable to that of patients who were initially treated correctly. In that article, we included STS larger than 5 cm, deep STS, and individuals with local recurrence. However, we wanted to evaluate the impact of unplanned resection on the survival of patients who had STS with the best prognosis, small and superficial STS, with two groups that were as homogeneous as possible. Do patients with small and superficial STS who underwent an unplanned resection have worse prognosis in the long term than those who were initially treated correctly? We exclusively evaluated patients with small (< 5 cm) and superficial (to the deep fascia) STS. We systematically excluded deep STS. Among this subset, we identified 93 patients with superficial STS. We excluded patients with local relapse, metastatic disease, superficial STS of the head or neck, those with insufficient clinical or dosimetric information, and patients with follow-up of less than 2 years. Furthermore, our focus on investigating the most benign and homogeneous STS prompted us to exclude patients with superficial tumors greater than or equal to 5 cm. This selection was driven by the presumed better prognosis associated with smaller tumors, inevitably leading to a smaller pool of patients for direct comparison with patients who had unplanned resections. The initial expectation was to observe similar survival outcomes between cohorts. Between 1990 and 2019, a total of 17 patients underwent surgical treatment at our private, medium-size center. Of those, 29% (5 patients) were lost to follow-up before 2 years without meeting a study endpoint (relapse, metastasis or revision, reoperation, or death), leaving a total of 71% (12 patients) of the original group who had either follow-up of at least 2 years or who met a study endpoint before that minimum surveillance duration. They were treated with surgery alone. During that same period, another 51 patients were referred to us after undergoing an unplanned resection of a lesion that subsequently was determined to be a soft tissue malignancy. Of those, 18% (9 patients) were lost to follow-up before 2 years without meeting a study endpoint, leaving 82% (42 patients) of the original group who had either follow-up of at least 2 years or who met a study endpoint before that minimum surveillance duration. They were treated with re-excision and postoperative radiotherapy. Patients with unplanned resections had an older mean age (51± 5 versus 44 ± 7 years; p = 0.1) and a higher proportion of female patients (58% versus 38%; p = 0.07), but the groups did not differ in terms of largest diameter, histologic type, or tumor location. However, patients with planned resections had a higher proportion of high-grade STS (75% versus 55%; p = 0.07). No metastases were present in either group at diagnosis. We performed a univariate analysis of the groups. We could not perform a multivariate analysis because of the small sample. We compared the groups in terms of local recurrence and all-cause mortality using the Kaplan-Meier survivorship estimator. According to the Kaplan-Meier survivorship estimator, survivorship free from local recurrence at a mean of 20 years of follow-up was better in the planned resection group than in the unplanned resection group (92% [95% CI 63% to 100%] versus 69% [95% CI 54% to 81%]; p = 0.04). Furthermore, overall survivorship at 5 years was higher in the planned resection group than in the unplanned resection group (100% [95% CI 72% to 100%] versus 70% [95% CI 54% to 81%]; p = 0.04). Similarly, the planned resection group exhibited superior survivorship at 20 years of follow-up (100% [95% CI 72% to 100%] versus 62% [95% CI 47% to 75%]; p = 0.01). Metastatic disease was absent in the planned resection group, while it occurred in 12 patients in the unplanned resection group (28% [95% CI 17% to 44%]). Unplanned resection for patients with small and superficial STS was associated with a decrease in overall survival in the long term, despite the use of postoperative radiotherapy. An unplanned resection may be an important prognostic factor. Nevertheless, larger and prospective studies are needed to validate our findings. Although small and superficial lumps are usually benign, nonsarcoma surgeons should be aware that some masses may be malignant, and if in doubt, MR imaging, a biopsy before excision, or consultation with or referral to a sarcoma center should be considered before removing the mass. Level III, therapeutic study.

Progress in the treatment of soft tissue sarcoma in the 2023 annual meeting of the American Society of Clinical Oncology

Soft tissue sarcoma (STS) is a group of rare malignant tumors originating from mesenchymal tissue, with a high degree of malignancy and a wide range of pathological subtypes. The prognosis varies among different subtypes, and treatment increasingly relies on selecting appropriate treatment methods for different subtypes. Surgical treatment is still the main treatment method at present, and the development of immune and targeted therapy also brings new hope for the treatment of soft tissue sarcoma. Immune checkpoint inhibitors, oncolytic viruses and T cell therapy have shown well safety and efficacy in clinical trials. Targeted drugs such as trabectedin and lenvatinib have changed the treatment pattern of soft tissue sarcoma. Currently, chemotherapy based on doxorubicin and ifosfamide is still the first line treatment for patients with advanced soft tissue sarcoma who have distant metastasis. However, the adverse reactions of doxorubicin limit its application in elderly patients, and trofosfamide has shown good efficacy and safety as an alternative in clinical trials. The efficacy of postoperative radiotherapy has been confirmed, which can reduce the local recurrence rate after surgical resection of soft tissue sarcoma. In summary, multimodal comprehensive treatment has become the main strategy for the treatment of soft tissue sarcoma. The combination of different treatment methods can generate synergistic effects and help patients obtain more clinical benefits, such as the combination of doxorubicin and immune checkpoint inhibitors, and the combination of antiangiogenic drugs and chemotherapy drugs. At the 2023 annual meeting of the American Society of Clinical Oncology (ASCO), oncologists from all over the world reported many researches related to the treatment of soft tissue sarcoma. This article aims to review the new progress in the treatment of soft tissue sarcoma in the 2023 annual meeting of ASCO.

Vezani muskulokutani režanj trapeziusa u rekonstrukciji defekta u regiji ramena nakon resekcije mekotkivnog sarkoma - prikaz slučaja i pregled literature

Introduction: Soft tissue sarcomas (STS) in the extremities require complex treatment involving limb-sparing surgery with adjuvant therapy. The treatment involves tumor resection with wide margins along with additional radiation and/ or chemotherapy. In addition to tumor resection, an important aspect is the reconstruction of the resulting soft tissue defect. For extensive reconstructive procedures in the upper extremities, literature suggests the use of free or pedicled flaps. In the shoulder region, due to its complex regional anatomy, selecting an appropriate flap is the surgical imperative. Recently, there has been significant interest in the use of the pedicled trapezius musculocutaneous flap, which offers certain advantages over other flaps. Case report: A female patient (31 years old) with STS in the left shoulder region, was surgically treated three times. The first surgery involved an intralesional procedure - R2 resection when a pleomorphic dermal sarcoma was diagnosed. After five months, a recurrence of the disease was detected based on magnetic resonance imaging (MRI) findings at the site of the surgical scar. Tumor resection was performed, and the soft tissue defect was covered with a free Thiersch partial-thickness skin graft. Histopathological analysis revealed a high-grade leiomyosarcoma. Two months after the second surgery, MRI findings confirmed a recurrence of the disease. Wide tumor resection was conducted, and the soft tissue defect was covered with a pedicled lower trapezius musculocutaneous flap. Conclusion: The literature lacks studies describing the outcomes of the use of trapezius flaps in the reconstruction of defects in the shoulder region following STS resection. Additionally, there is no unanimous official opinion on the resection margin width that is considered safe. The treatment outcome of our patient indicates the significant potential and advantages of the trapezius flap, as compared to other flaps of that region.

Lipid profiling of electrosurgical vapors for real-time assistance of soft tissue sarcoma resection.

Soft tissue sarcomas (STS) constitute a heterogeneous group of rare tumor entities. Treatment relies on challenging patient-tailored surgical resection. Real-time intraoperative lipid profiling of electrosurgical vapors by rapid evaporative ionization mass spectrometry (REIMS) may aid in achieving successful surgical R0 resection (i.e., microscopically negative-tumor margin resection). Here, we evaluate the ex vivo accuracy of REIMS to discriminate and identify various STS from normal surrounding tissue. Twenty-seven patients undergoing surgery for STS at Maastricht University Medical Center+ were included in the study. Samples of resected STS specimens were collected and analyzed ex vivo using REIMS. Electrosurgical cauterization of tumor and surrounding was generated successively in both cut and coagulation modes. Resected specimens were subsequently processed for gold standard histopathological review. Multivariate statistical analysis (principal component analysis-linear discriminant analysis) and leave-one patient-out cross-validation were employed to compare the classifications predicted by REIMS lipid profiles to the pathology classifications. Electrosurgical vapors produced during sarcoma resection were analyzed in vivo using REIMS. In total, 1200 histopathologically-validated ex vivo REIMS lipid profiles were generated from 27 patients. Ex vivo REIMS lipid profiles classified STS and normal tissues with 95.5% accuracy. STS, adipose and muscle tissues were classified with 98.3% accuracy. Well-differentiated liposarcomas and adipose tissues could not be discriminated based on their respective lipid profiles. Distinction of leiomyosarcomas from other STS could be achieved with 96.6% accuracy. In vivo REIMS analyses generated intense mass spectrometric signals. Lipid profiling by REIMS is able to discriminate and identify STS with high accuracy and therefore constitutes a potential asset to improve surgical resection of STS in the future.