Does Wound VAC Temporization Offer Patient-Reported Outcomes Similar to Single-Stage Excision Reconstruction After Myxofibrosarcoma Resection?

BACKGROUND: Vacuum-assisted closure (VAC) temporization is a promising technique to achieve local control in aggressive soft tissue sarcomas. Despite its previously reported efficacy, adoption of VAC temporization remains limited, primarily due to the scarce literature on patient-reported outcomes (PROs) supporting its efficacy. This study compared the postoperative PROs after VAC temporization or single-stage (SS) excision and reconstruction for patients undergoing surgical resection for myxofibrosarcoma management. METHODS: A retrospective analysis of myxofibrosarcoma patients who underwent surgical resections at our institution from 2016 to 2022 was performed. Postoperative PROs collected prospectively for those treated with VAC temporization or SS excision/reconstruction were compared using a visual analog scale (VAS) for pain and three Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaires: Global Health Short-Form Mental (SF Mental), Global Health Short-Form Physical (SF Physical), and Physical Function Short-Form 10a (SF 10a). Absolute and differential (postoperative minus preoperative) scores at the 1-month, 3-month, 6-month, 1-year, and 2-year time points were compared. RESULTS: The analysis included 79 patients (47 treated with VAC temporization and 32 treated with SS excision/reconstruction). All outcomes were similar between the groups except for physical function 1 year after surgery, in which the differential PROMIS SF 10a scores were higher in the SS group (p = 0.001). All the remaining absolute and differential PROMIS and VAS pain scores were similar between the groups at all time points. Postoperative complications did not differ between the groups. CONCLUSION: The PROs for physical and mental health, physical function, and pain were similar between the myxofibrosarcoma patients who had VAC temporization and those who had SS excision/reconstruction after surgical resection.

Risk factors for local recurrence of upper extremity desmoid tumors.

INTRODUCTION: Upper extremity (UE) desmoid tumors are locally aggressive neoplasms with high recurrence rates. Our study sought to analyze the demographics and treatment strategies of UE desmoid tumors and identify risk factors for recurrence. MATERIALS AND METHODS: A retrospective review of 52 patients with histologically confirmed UE desmoid tumors treated at our institution between 1990 and 2015 was conducted. Survival was assessed using the Kaplan-Meier method and the Cox proportional hazards model was used for risk factor analysis. RESULTS: For the entire cohort, median age was 40 (29-47) years, 75% were female, and 48% had local recurrence. The median tumor size was 45 (15-111) cm3 on imaging. Twenty-two patients had a previous resection. The most common treatments were surgery alone (50%) and surgery with adjuvant radiotherapy (21%). Tumor size ≥5 cm and tumor volume ≥40 cm3 on imaging were associated with increased recurrence (p = 0.006 and p = 0.005, respectively). Age and sex were not associated with local recurrence. Patients with a tumor size ≥5 cm were 2.6 times more likely to present with recurrence. At the 10-year mark, a lower local recurrence-free survival was seen in patients with tumors ≥5 cm (72.2% vs. 36.3%, p = 0.042) or ≥40 cm3 (67.2% vs. 32.7%, p = 0.034). CONCLUSION: In our study, only tumor dimensions appeared to modify recurrence risk.

Prediction of 5-year survival in soft tissue leiomyosarcoma using a machine learning model algorithm.

BACKGROUND AND OBJECTIVES: Leiomyosarcoma (LMS) is associated with one of the poorest overall survivals among soft tissue sarcomas. We sought to develop and externally validate a model for 5-year survival prediction in patients with appendicular or truncal LMS using machine learning algorithms. METHODS: The Surveillance, Epidemiology, and End Results (SEER) database was used for development and internal validation of the models; external validation was assessed using our institutional database. Five machine learning algorithms were developed and then tested on our institutional database. Area under the receiver operating characteristic curve (AUC) and Brier score were used to assess model performance. RESULTS: A total of 2209 patients from the SEER database and 81 patients from our tertiary institution were included. All models had excellent calibration with AUC 0.84-0.85 and Brier score 0.15-0.16. After assessing the performance indicators according to the TRIPOD model, we found that the Elastic-Net Penalized Logistic Regression outperformed other models. The AUCs of the institutional data were 0.83 (imputed) and 0.85 (complete-case analysis) with a Brier score of 0.16. CONCLUSION: Our study successfully developed five machine learning algorithms to assess 5-year survival in patients with LMS. The Elastic-Net Penalized Logistic Regression retained performance upon external validation with an AUC of 0.85 and Brier score of 0.15.

Wound vacuum-assisted closure temporization after tumor resection of soft tissue sarcomas-A cost analysis in a propensity-score matched population.

BACKGROUND: Vacuum-assisted closure (VAC) temporization is a technique associated with high local control rates used in myxofibrosarcoma. We sought to compare the costs and postoperative outcomes of VAC temporization and single-stage (SS) excision/reconstruction. METHODS: We conducted a retrospective analysis of patients with myxofibrosarcoma surgically treated at our institution between 2000 and 2022. Variables of interest included total, direct, and indirect costs for initial episode of care, 90 days and 1 year after initial admission, and postoperative outcomes. Costs were compared between the VAC temporization and SS groups. RESULTS: After matching, 13 patients in the SS group and 23 in the VAC group were analyzed. We found no difference in median and mean total inpatient costs, between the VAC temporization and SS group. While total 90-day and 1-year costs were higher in the VAC group compared to the SS group, mean costs were similar. There were no differences in postoperative complications between groups. A subanalysis of the entire cohort (n = 139) revealed lower local recurrence and overall death rates in the VAC temporization group. CONCLUSION: VAC temporization had similar inpatient costs and postoperative outcomes to SS excision/reconstruction. While median 90-day and 1-year costs were higher in the VAC group, mean costs did not differ.

Factors associated with skeletal-related events in patients with bone metastatic melanoma: A retrospective study of 481 patients.

OBJECTIVES: Metastatic bone disease is estimated to develop in up to 17% of patients with melanoma, compromising skeleton integrity resulting in skeletal-related events (SREs), which impair quality of life and reduce survival. The objective of the study was to investigate (1) the proportion of melanoma patients developing SREs following diagnosis of bone metastasis and (2) the predictors for SREs in this patient cohort. METHODS: Four hundred and eighty-one patients with bone metastatic melanoma from two tertiary centers in the United States from 2008 to 2018 were included. The primary outcome was 90-day and 1-year occurrence of a SRE, including pathological fractures of bones, cord compression, hypercalcemia, radiotherapy, and surgery. Fine-Gray regression analysis was performed for overall SREs and pathological fracture, with death as a competing risk. RESULTS: By 1-year, 52% (258/481) of patients experienced SREs, and 28% (137/481) had a pathological fracture. At 90-day, lytic lesions, bone pain, elevated calcium and absolute lymphocyte, and decreased albumin and hemoglobin were associated with higher SRE risk. The same factors, except for decreased hemoglobin, were shown to predict development of SREs at 1-year. CONCLUSION: The high incidence of SREs and pathological fractures warrants vigilance using the identified factors in this study and preventative measures during clinical oncological care.

Phosphaturic mesenchymal tumor: management and outcomes of ten patients treated at a single institution.

BACKGROUND: Phosphaturic mesenchymal tumor (PMT) is a rare tumor that causes tumor-induced osteomalacia. Patients present with non-specific symptoms secondary to renal phosphate wasting and decreased bone mineralization. We sought to assess: (1) What are the common presenting features, laboratory and imaging findings, histologic findings of phosphaturic mesenchymal tumors? (2) What are the available treatment strategies for phosphaturic mesenchymal tumors and their long-term outcomes in terms of local recurrence and symptom control after treatment? METHODS: We retrospectively identified patients with a histologic diagnosis of PMT located in the axial or appendicular skeleton, or surrounding soft tissues. A total of 10 patients were finally included in our study. RESULTS: Median tumor size was 1.9 cm (range, 1.1 to 6.1) and median time from symptom onset to diagnosis was 3 years (range, 0.5 to 15 years). All patients but one presented with hypophosphatemia (median 1.9 mg/dL, range 1.2 to 3.2). Pre-operative FGF-23 was elevated in all cases (median 423.5 RU/mL, range 235 to 8950). Six patients underwent surgical resection, three were treated percutaneously (radiofrequency ablation or cryoablation), and one refused treatment. Only one patient developed local recurrence and no patients developed metastatic disease. At last follow-up, nine patients showed no evidence of disease and one was alive with disease. CONCLUSION: Phosphaturic mesenchymal tumor is a rare tumor presenting with non-specific symptoms. Surgery is the standard treatment when negative margins can be achieved without significant morbidity. In patients with small tumors in surgically-inaccessible areas, radiofrequency ablation or cryoablation can be performed successfully.

Complications and functional outcomes after reconstruction of the proximal humerus with allograft-prosthetic composite: a systematic review of the literature.

BACKGROUND: Allograft prosthetic composite (APC) reconstruction is performed after resection of proximal humerus tumors or failure of arthroplasty implants. There is limited literature on the postoperative outcomes of this technique. We sought to assess implant survival, failure rates, and postoperative functional outcomes after APC reconstruction of the proximal humerus. METHODS: A systematic review of the PubMed and Embase databases was conducted. The study was registered on PROSPERO (ID: 448,663). The Strengthening of the Reporting of Observational Studies in Epidemiology checklist was used for quality assessment. Implant failure was determined using the Henderson classification for biological reconstruction. Functional outcome was primarily assessed using the Musculoskeletal Tumor Society score at last follow-up. RESULTS: Twenty-five studies with a total of 488 patients were included. Mean follow-up in reporting studies ranged from 2.5 to 10 years. Five-year revision-free survival for implants ranged from 41% to 92%. Overall implant failure rate ranged from 9% to 54%, and reoperation rate ranged from 0% to 55%. Graft host nonunion (type 2) was the most common mode of failure, with rates ranging from 0% to 75%. The mean Musculoskeletal Tumor Society scores at last follow-up ranged from 57% to 90% across studies. A trend towards better functional outcomes was seen in patients having an APC with a reverse total shoulder arthroplasty (rTSA) compared with those with hemiarthroplasty. CONCLUSIONS: APCs show promise in proximal shoulder reconstruction, with heterogeneous functional outcomes that are noninferior to other reconstruction techniques. Graft host nonunion is a common mode of failure and remains a concern in this type of prosthesis. Future studies should compare rTSA-APCs and rTSA endoprostheses while controlling for potential confounders.

Reconstruction of the elbow with distal humerus endoprosthetic replacement after tumor resection: a systematic review of the literature and institutional case series.

BACKGROUND: Distal humerus replacement (DHR) is a modular endoprosthesis mainly used for bone reconstruction after resection of primary or metastatic bone lesions. Studies on DHR failure rates and postoperative functional outcomes are scarce. We sought to assess implant survival, modes of failure, and functional outcomes in patients undergoing DHR for oncologic indications. METHODS: A systematic review of the PubMed and Embase databases was performed. PRISMA guidelines were followed for this manuscript. Our study was registered on PROSPERO (457,260). Quality appraisal of included studies was conducted using the STROBE checklist. Prosthetic failure was assessed using the Henderson classification for megaprosthetic failures. We additionally performed a retrospective review of patients treated with a DHR for oncologic indications at a large tertiary care academic center. Weighted means were calculated to pool data. RESULTS: Eleven studies with a total of 162 patients met the inclusion criteria. Mean follow-up was 3.7 years (range, 1.66-8 years). Henderson type 2 failures (aseptic loosening) were the most common mode of failure, occurring in 12% of cases (range, 0%-33%). Five-year implant survival was 72% (range, 49%-93.7%). Mean postoperative Musculoskeletal Tumor Society (MSTS) score was 81.1 (range, 74-84.3). In our institutional case series, 2 out of 5 patients had DHR revision for periprosthetic fracture and aseptic loosening at 16 and 27 months after surgery, respectively. CONCLUSIONS: Distal humerus replacement is a successful reconstruction strategy for tumors of the distal humerus, with high implant survival and good to excellent functional outcomes.

Debridement, Antibiotics, and Implant Retention (DAIR) Plus Offers Similar Periprosthetic Joint Infection Treatment Success Rates to Two-Stage Revision in Oncologic Megaprosthesis.

BACKGROUND: Prosthetic joint infections (PJIs) after megaprosthesis implantation are associated with high rates of treatment failure and amputation. Our study analyzed PJI treatment success rates by surgical strategy and assessed risks of reinfection and amputation. METHODS: We retrospectively analyzed the outcomes of patients diagnosed with PJI after undergoing megaprosthesis implantation for oncologic indications. The 2011 Musculoskeletal Infection Society criteria were used to define PJI. Reinfection, reoperation, and amputation for PJI recurrence were assessed. A total of 67 patients with megaprosthesis PJIs were included. There were fourteen patients who were treated with debridement, antibiotics, and implant retention (DAIR), 31 with DAIR plus (DAIR with modular component exchange and stem retention), and 21 with two-stage revisions. Kaplan-Meier estimates were used for survival analyses and Cox proportional hazards for risk factor analyses. RESULTS: The two-year reinfection-free survival was 25% for DAIR and 60% for DAIR plus or two-stage revision (P = .049). The five-year amputation-free survival was 84% for DAIR plus or two-stage revision, and 48% for DAIR (P = .13). Reinfection-free, reoperation-free, and amputation-free survival were similar between DAIR plus and two-stage revision at the 2- and 5-year marks. Body mass index ≥30 (hazard ratio [HR] = 2.65) and chronic kidney disease (HR = 11.53) were risk factors for reinfection. Treatment with DAIR plus or two-stage revision (HR = 0.44) was a protective factor against reinfection. CONCLUSIONS: A DAIR was associated with high rates of treatment failure and higher amputation rates than DAIR plus or 2-stage surgery. A DAIR plus was not inferior to 2-stage revision clearing a PJI and might be performed in patients who cannot withstand two-stage revision surgery.

Complete tumor necrosis after neoadjuvant chemotherapy defines good responders in patients with Ewing sarcoma.

BACKGROUND: Survival in patients who have Ewing sarcoma is correlated with postchemotherapy response (tumor necrosis). This treatment response has been categorized as the response rate, similar to what has been used in osteosarcoma. There is controversy regarding whether this is appropriate or whether it should be a dichotomy of complete versus incomplete response, given how important a complete response is for in overall survival of patients with Ewing sarcoma. The purpose of this study was to evaluate the impact that the amount of chemotherapy-induced necrosis has on (1) overall survival, (2) local recurrence-free survival, (3) metastasis-free survival, and (4) event-free survival in patients with Ewing sarcoma. METHODS: In total, 427 patients who had Ewing sarcoma or tumors in the Ewing sarcoma family and received treatment with preoperative chemotherapy and surgery at 10 international institutions were included. Multivariate Cox proportional-hazards analyses were used to assess the associations between tumor necrosis and all four outcomes while controlling for clinical factors identified in bivariate analysis, including age, tumor volume, location, surgical margins, metastatic disease at presentation, and preoperative radiotherapy. RESULTS: Patients who had a complete (100%) tumor response to chemotherapy had increased overall survival (hazard ratio [HR], 0.26; 95% CI, 0.14-0.48; p < .01), recurrence-free survival (HR, 0.40; 95% CI, 0.20-0.82; p = .01), metastasis-free survival (HR, 0.27; 95% CI, 0.15-0.46; p ≤ .01), and event-free survival (HR, 0.26; 95% CI, 0.16-0.41; p ≤ .01) compared with patients who had a partial (0%-99%) response. CONCLUSIONS: Complete tumor necrosis should be the index parameter to grade response to treatment as satisfactory in patients with Ewing sarcoma. Any viable tumor in these patients after neoadjuvant treatment should be of oncologic concern. These findings can affect the design of new clinical trials and the risk-stratified application of conventional or novel treatments.

Prognostic Significance of Percentage and Size of Dedifferentiation in Dedifferentiated Chondrosarcoma.

Dedifferentiated chondrosarcoma is rare, aggressive, and microscopically bimorphic. How pathologic features such as the amounts of dedifferentiation affect prognosis remains unclear. We evaluated the percentages and sizes of dedifferentiation in a consecutive institutional series of dedifferentiated chondrosarcomas from 1999 to 2021. The statistical analysis included cox proportional hazard models and log-rank tests. Of the 67 patients (26 women, 41 men; age, 39 to >89 [median 61] years; 2 with Ollier disease), 58 presented de novo; 9 were identified with conventional chondrosarcomas 0.6-13.2 years (median, 5.5 years) prior. Pathologic fracture and distant metastases were noted in 27 and 7 patients at presentation. The tumors involved the femur (n = 27), pelvis (n = 22), humerus (n = 7), tibia (n = 4), scapula/ribs (n = 4), spine (n = 2), and clivus (n = 1). In the 56 resections, the tumors ranged in size from 3.5 to 46.0 cm (median, 11.5 cm) and contained 1%-99.5% (median, 70%) dedifferentiated components that ranged in size from 0.6 to 24.0 cm (median, 7.3 cm). No correlation was noted between total size and percentage of dedifferentiation. The dedifferentiated components were typically fibrosarcomatous or osteosarcomatous, whereas the associated cartilaginous components were predominantly grade 1-2, rarely enchondromas or grade 3. The entire cohort's median overall survival and progression-free survival were 11.8 and 5.4 months, respectively. In the resected cohort, although the total size was not prognostic, the percentage of dedifferentiation ≥20% and size of dedifferentiation >3.0 cm each predicted worse overall survival (9.9 vs 72.5 months; HR, 3.76; 95% CI, 1.27-11.14; P = .02; 8.7 vs 58.9 months; HR, 3.03; 95% CI, 1.21-7.57; P = .02, respectively) and progression-free survival (5.3 vs 62.1 months; HR, 3.05; 95% CI, 1.13-8.28; P = .03; 5.3 vs 56.6 months; HR, 2.50; 95% CI, 1.06-5.88; P = .04, respectively). In conclusion, both the percentages and sizes of dedifferentiation were better prognostic predictors than total tumor sizes in dedifferentiated chondrosarcomas, highlighting the utility of their pathologic evaluations.

Venous Thromboembolic Event Following Soft Tissue Sarcoma Diagnosis is Associated with the Development of Pulmonary Metastasis.

BACKGROUND: This study aimed to investigate whether venous thromboembolic events (VTEs) are clinically relevant predictors of pulmonary metastatic disease in patients with soft tissue sarcomas (STSs). PATIENTS AND METHODS: In this retrospective cohort analysis, we included patients with STS surgically treated for sarcoma between January 2002 and January 2020. The primary outcome of interest was development of pulmonary metastasis after non-metastatic STS diagnosis. Tumor depth, stage, type of surgical intervention, chemotherapy, radiation therapy, body mass index, and smoking status were collected. Episodes of VTEs following STS diagnosis, including deep vein thrombosis, pulmonary embolism, and other thromboembolic events, were also obtained. Univariate analyses and multivariable logistic regression were used to identify potential predictors for pulmonary metastasis. RESULTS: We included 319 patients with mean age of 54.9 ± 16 years. Thirty-seven patients (11.6%) had VTE after STS diagnosis, and 54 (16.9%) developed pulmonary metastasis. Univariate screening revealed pulmonary metastasis, pre- and postoperative chemotherapy, smoking history, and VTE after surgery as potential predictors of pulmonary metastasis. Multivariable logistic regression revealed smoking history [odds ratio (OR) 2.0, confidence interval (CI) 1.1-3.9, P = 0.04] and VTE (OR 6.3, CI 2.9-13.6, P < 0.001) as independent risk factors for predicting pulmonary metastasis in patients with STS, after adjusting for the factors in the univariate screening as well as age, sex, stage of the tumor, and neurovascular invasion. CONCLUSIONS: Patients with VTE after STS diagnosis have an odds ratio of 6.3 for developing metastatic pulmonary disease compared with patients without venous thromboembolic events. Smoking history was also associated with future pulmonary metastases.

Multifocal heterotopic ossification in a man with germline variants of LIM Mineralization Protein-1 (LMP-1).

A 54-year-old man with a history of unimelic, post-traumatic multifocal heterotopic ossification (HO) and normal genetic analysis of ACVR1 and GNAS had variants of unknown significance (VUS) in PDLIM-7 (PDZ and LIM Domain Protein 7), the gene encoding LMP-1 (LIM Mineralization Protein-1), an intracellular protein involved in the bone morphogenetic protein (BMP) pathway signaling and ossification. In order to determine if the LMP-1 variants were plausibly responsible for the phenotype observed, a series of in vitro experiments were conducted. C2C12 cells were co-transfected with a BMP-responsive reporter as well as the LMP-1 wildtype (wt) construct or the LMP-1T161I or the LMP-1D181G constructs (herein designated as LMP-161 or LMP-181) corresponding to the coding variants detected in the patient. A significantly increased BMP-reporter activity was observed in LMP-161 or LMP-181 transfected cells compared to the wt cells. The LMP-181 variant exhibited BMP-reporter activity with a four-fold increase over the LMP-1 wt protein. Similarly, mouse pre-osteoblastic MC3T3 cells transfected with the patient's LMP-1 variants expressed higher levels of osteoblast markers both at mRNA and protein levels and preferentially mineralized when stimulated with recombinant BMP-2 compared to control cells. Presently, there are no pathogenic variants of LMP-1 known to induce HO in humans. Our findings suggest that the germline variants in LMP-1 detected in our patient are plausibly related to his multifocal HO (LMP1-related multifocal HO). Further observations will be required to firmly establish this gene-disease relationship.

Risk factors for 30-day soft tissue complications after pelvic sarcoma surgery: A National Surgical Quality Improvement Program study.

INTRODUCTION: Soft tissue (ST) complications after resection of bone and ST sarcomas of the pelvis occur more frequently than in appendicular tumors. We sought to identify risk factors for complications within 30 days of surgery. METHODS: The National Surgical Quality Improvement Program database was used for this study. Patients with sarcomas of bone and ST of the pelvis were retrieved using Current Procedural Terminology and International Classification of Diseases codes. Outcomes assessed were ST complications, overall complication rates, 30-day reoperation, and mortality. RESULTS: A total of 770 patients with pelvic bone and ST sarcoma were included. The ST complication rate was 12.6%, including 4.9% superficial and 4.7% deep surgical site infections. Higher ST complication rates were seen in patients >30 years, with partially dependent health status, hematocrit <30%, bone tumors, tumor >5 cm, amputation procedures, and longer operative times. ST complication rates were 1.5 and 3 times higher in pelvic sarcoma surgeries than in the lower and upper extremities, respectively. Age >30 years (odds ratio [OR] = 5.07), hematocrit <30% (OR = 1.84), operative time 1-3 h (OR = 2.97), and >3 h (OR = 4.89) were risk factors for ST complications. CONCLUSION: One in nine patients with pelvic sarcoma surgery will develop ST complications within 30 days. Risk factors for ST complications were age >30, hematocrit <30%, and longer operative time.

Giant cell-rich osteosarcoma: A match pair analysis of 11 new cases and literature review of 56 patients.

BACKGROUND: Limited remains known on giant cell-rich osteosarcoma (GCRO) with current studies being case reports or smaller series. This investigation compared GCRO and conventional osteoblastic osteosarcoma (OOS) with regard to demographics and survival. METHODS: An institutional tumor registry was used to identify 11 patients (six males) treated for GCRO. Mean age was 43 years. Staging showed American Joint Committee on Cancer (AJCC) stages IIA in four and IIB in seven patients. Mean follow-up was 14 years. Study initiatives were: (1) Comparison of demographics between GCRO and 167 OOS from our institutional registry, (2) Differences in survival between GCRO and 33 OOS case controls (based on sex and AJCC stage), as well as 10 OOS using an age-based propensity match, and (3) Summary of all GCRO cases reported in the literature. RESULTS: (1) Sex (p = 0.53), grading (p = 0.56), AJCC stage (p = 0.42), and chemotherapeutic response rate (p = 0.67) did not differ between groups. Age was significantly increased in GCRO (p = 0.001). (2) Case-control and propensity-matched groups revealed no difference in disease-free survival, local recurrence, and distant disease-free survival at 2 years (p > 0.05). (3) Mean age of 56 patients (50% males) reported in the literature was 26 years. After merging with our 11 cases, the 2-year disease-free survival was 66%. CONCLUSIONS: GCRO remains a rare disease with high short-term mortality. Although affecting older patients more than conventional osteosarcoma, GCRO should not be viewed as a predictor of survival compared to OOS.

Prognostic and predictive factors in undifferentiated pleomorphic sarcoma: A long-term study from a large tertiary care urban center.

BACKGROUND AND OBJECTIVES: Undifferentiated pleomorphic sarcoma (UPS) is an aggressive type of soft tissue sarcoma (STS) with high rates of metastatic disease and local recurrence. We sought to identify risk factors for local recurrence, metastasis, and overall death, and assess their impact on overall survival (OS), local recurrence-free survival (LRFS), and metastasis-free survival (MFS). METHODS: A total of 386 cases of UPS treated at our institution from 1980 to 2020 were included. Cox proportional hazards regression was used to identifying risk factors for death, local recurrence, and/or metastasis. Using the Kaplan-Meier method, we assessed OS, LRFS, and MFS. RESULTS: Sixty-six (17%) and 121 (30%) patients with UPS developed local recurrence or metastasis, respectively. Lymph node (LN) involvement was present in 13.5% of patients. The most affected organ in patients with metastatic disease was the lungs (76.9%). Age ≥ 60 (hazard ratio [HR] = 2.42) and size ≥7 cm (HR = 1.52) were some of the significant risk factors for overall death. LN involvement was an important risk factor for both LR (HR = 2.79) and distant metastasis (HR = 5.73). CONCLUSIONS: UPS displays high rates of metastatic disease and local recurrence. Using a tumor size cutoff value of 7 cm yields superior prognostic value than the standard STS T-score thresholds. Lymphovascular invasion is an important risk factor for the development of metastasis.

Assessment of the added value of intravenous gadolinium for knee osteosarcoma resection planning in pediatric and young adult patients.

BACKGROUND AND OBJECTIVES: To assess the impact of Gadolinium-enhanced magnetic resonance imaging (MRI) sequences on Preoperative imaging evaluation and surgical planning parameters for osteosarcoma (OS) of the knee in pediatric and young adult patients. METHODS: Thirty MRI scans of patients with OS about the knee were reviewed by five orthopedic oncologists. Key preoperative parameters (neurovascular bundle involvement, intra-articular tumor extension, extent of intramedullary extension) and surgical plans were evaluated based on non-contrast versus Gd contrast enhanced sequences. Assessment agreement, inter-rater agreement, and intrarater agreement between pre and postcontrast images were evaluated via Kappa statistics. RESULTS: Moderate agreement was seen between non and contrast-enhanced assessment of neurovascular involvement and intra-articular tumor extension. Intrarater reproducibility was substantial for neurovascular bundle involvement (precontrast Kappa: 0.63, postcontrast Kappa: 0.69). Intrarater reproducibility was also substantial for precontrast (Kappa: 0.70) and moderate for postcontrast (Kappa: 0.50) assessment of intra-articular tumor extension. Planned resection length and choice of surgical approach were similar between sequences. The addition of Gd-enhanced sequences improved the inter-rater agreement across collected parameters. CONCLUSIONS: While some findings suggest that contrast enhanced sequences may not significantly alter the assessment of key preoperative planning parameters by orthopedic oncologists, they may help reduce variability among providers with differing experience levels.

Are Pathologic Fractures in Patients With Osteosarcoma Associated With Worse Survival Outcomes? A Systematic Review and Meta-analysis.

BACKGROUND: Pathologic fractures occur in 5% to 10% of patients with osteosarcoma, and prior studies have suggested they are prognostically important. However, because they represent an uncommon event in the setting of an already rare disease, most studies fail to reach conclusive findings, and there is no agreement about how best to treat pathologic fractures. QUESTIONS/PURPOSES: (1) Is the occurrence of a pathologic fracture in patients with osteosarcoma associated with poorer overall survivorship? (2) Is the occurrence of a pathologic fracture in patients with osteosarcoma associated with poorer local recurrence-free survival or metastasis-free survival? (3) Is the surgical approach (amputation or limb salvage) associated with differences in local recurrence rates in patients with osteosarcoma with pathologic fractures? METHODS: This systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Our study was registered in PROSPERO (ID: 380459). A search of the PubMed and Embase databases resulted in 625 and 747 titles, respectively. After application of the inclusion and exclusion criteria, 21 articles were finally included. Quality assessment of all studies was performed using the Newcastle-Ottawa Quality Assessment Scale. The Risk of Bias In Non-Randomized Studies of Interventions tool was used in the 11 articles that evaluated the effect of an intervention (amputation or limb salvage) on local recurrence rates. The relative risk (RR) was calculated to compare outcomes in patients with osteosarcoma with pathologic fractures and those without. Heterogeneity among studies was calculated using the I 2 statistic. The pooled RR was calculated using the fixed-effects or random-effects model depending on study heterogeneity. The fragility index and the ratio between the fragility index and the total number of participants for each outcome was additionally calculated to assess the robustness of our results. A total of 7604 patients with osteosarcoma, 12% of whom (885) had pathologic fractures, were included in our analysis. RESULTS: Pathologic fractures in patients with osteosarcoma were associated with lower 3-year (RR 1.53 [95% CI 1.29 to 1.82]; p < 0.001) and 5-year overall survival (RR 1.27 [95% CI 1.16 to 1.40]; p < 0.001). No difference in recurrence rates was found between patients with osteosarcoma with pathologic fractures and those without (RR 1.22 [95% CI 0.91 to 1.64]; p = 0.18). However, having a pathologic fracture was associated with an increased risk of developing metastasis (RR 1.33 [95% CI 1.08 to 1.63]; p = 0.01). Treatment with limb salvage surgery was not associated with a higher rate of local recurrence (RR 1.58 [95% CI 0.88 to 2.85]; p = 0.13). CONCLUSION: In light of these findings, surgeons should be aware that after appropriate case selection, patients with osteosarcoma and pathologic fractures undergoing limb salvage surgery may have similar rates of local recurrence to those undergoing amputation. Therefore, a pathologic fracture may no longer be an absolute contraindication for limb salvage surgery. Future studies adjusting for potential confounders such as tumor size, tumor location, and response to neoadjuvant therapy would provide further insight into the effect of pathologic fractures on our assessed outcomes. LEVEL OF EVIDENCE: Level III, therapeutic study.

High Rates of Treatment Failure and Amputation in Modular Endoprosthesis Prosthetic Joint Infections Caused by Fungal Infections With Candida.

BACKGROUND: Fungal prosthetic joint infections (PJIs) are rare yet severe events associated with high rates of recurrent infection. Although bacterial PJIs associated with megaprostheses are known to be associated with higher rates of recurrence and amputation, little is known about fungal PJIs near megaprostheses. QUESTIONS/PURPOSES: In patients with fungal megaprosthesis PJIs from one institutional registry, We asked: (1) what were the most common microorganisms isolated? (2) What were the reoperation-, revision-, and amputation-free survival rates 1 and 2 years after surgery? METHODS: We conducted a retrospective analysis of megaprostheses in our institutional database. Between 2000 and 2022, 86 patients with a diagnosis of PJI after megaprosthesis implantation were surgically treated at our institution. We considered patients with microbiological cultures that were positive for fungal organisms and who had a minimum follow-up of 2 years from the initial treatment for PJI. Ten patients with fungal megaprosthesis PJIs were included. Although four patients had a follow-up shorter than 2 years, all reached one of the study endpoints at that earlier interval, and therefore were included. All included patients were treated between 2016 and 2022, and the diagnosis of PJI was made in accordance with the 2011 Musculoskeletal Infection Society criteria. Patients were treated with either debridement, antibiotics, and implant retention (DAIR), DAIR-plus (debridement, antibiotics, modular implant component exchange, and stem retention), or one-stage or two-stage revision. In general, DAIR was used for acute PJIs, while DAIR-plus was performed in patients with chronic PJIs who were deemed medically unfit to endure the high morbidity associated with removal of the stems. In cases of prior unsuccessful DAIR-plus or patients with fewer comorbidities, one-stage or two-stage revision was the main treatment approach. The median age at diagnosis was 67 years (range 32 to 84 years), 5 of 10 patients were female, and the median BMI was 31 kg/m2 (range 20 to 43 kg/m2). The median follow-up was 26 months (range 1 to 54 months). A Kaplan-Meier survival analysis was performed to calculate reoperation-, revision-, and amputation-free survival at 1 and 2 years from the index surgery for PJI. RESULTS: The two most common organisms were Candida albicans (5 of 10 patients) and C.parapsilosis (3 of 10). Six of 10 patients had coinfection with a bacterial organism. One-year reoperation-free and revision-free survival were 35% (95% CI 9% to 64%) and 42% (95% CI 11% to 71%), respectively. Two-year reoperation-free and revision-free survival were 12% (95% CI 1% to 40%) and 14% (95% CI 1% to 46%), respectively. Amputation-free survival was 74% (95% CI 30% to 93%) at the 1-year interval and 40% at the 2-year interval (95% CI 7% to 73%). At the final follow-up interval, four patients had undergone amputations and four were being administered chronic antifungal suppression. CONCLUSION: Megaprosthesis fungal PJIs are rare but devastating. Arthroplasty surgeons should consider treatment efficacy, which appears to be low across surgical strategies, and the patient's capacity to withstand it. A lower decision threshold for performing amputation may be considered in patients who require rapid infection control to initiate immunosuppressive treatments. Future studies should aim to compare the surgical and clinical outcomes of fungal PJIs with those of other etiologies while controlling for potential variables. Efforts should be made to establish multi-institutional collaborations to achieve larger study samples. LEVEL OF EVIDENCE: Level IV, therapeutic study.

What Are the Functional and Surgical Outcomes of Tibial Turnup-plasty for Salvage in Patients With Chronic Lower Extremity Infection?

BACKGROUND: Tibial turnup-plasty is a rarely performed surgical option for large bone defects of the distal or entire femur and can serve as an alternative to hip disarticulation or high above-knee amputation. It entails pedicled transport of the ipsilateral tibia with or without the proximal hindfoot for use as a vascularized autograft. It is rotated 180° in the coronal or sagittal plane to the remaining proximal femur or pelvis, augmenting the functional length of the thigh. Prior reports consist of small case series with heterogeneous surgical techniques. Patient-reported outcome measures after the procedure have not been reported, and ambulatory status after the procedure is also unknown. QUESTIONS/PURPOSES: (1) What proportion of patients underwent reoperation after tibial turnup-plasty? (2) What is the ambulatory status and what proportion of patients used a prosthesis after tibial turnup-plasty? (3) What are the Patient-Reported Outcome Measurement Information System (PROMIS) Global-10 mental and physical function scores after tibial turnup-plasty? METHODS: A retrospective analysis was performed of 11 patients who underwent tibial turnup-plasty between 2003 and 2021 by a single orthopaedic oncology division in collaboration with a reconstructive plastic surgery team. Nine patients were men, with a median age of 55 years (range 34 to 75 years). All had chronic infections after arthroplasty or oncologic reconstructions, with a median number of 13 surgeries before turnup-plasty. All were considered to have no other surgical options other than hip disarticulation or high transfemoral amputation. All patients who were offered this possibility accepted it. Data of interest included patient demographics and comorbidities, surgical history that led to limb compromise, medical and surgical perioperative complications, date of prosthesis fitting, and functional capacity at the most recent follow-up interval based on ambulatory status and PROMIS Global-10 mental and physical function scores. The statistical analysis was descriptive. RESULTS: The median number of reoperations after turnup-plasty was one (range 0 to 11). Of the six patients who underwent at least one reoperation, indications for surgery included wound infection (four patients), nonunion of the osteosynthesis site (two), heterotopic ossification (one), tumor recurrence (one), and flap hypoperfusion treated with local tissue revision (one). One patient underwent conversion to external hemipelvectomy for tumor recurrence. Ten of the 11 patients were ambulatory at the final follow-up interval with standard above-knee amputation prostheses. Two ambulated unassisted, four used a single crutch or cane, and four used two crutches or a walker. Of the nine patients for whom scores were available, the median PROMIS Global-10 physical and mental health scores were 48 (range 30 to 68) and 53 (range 41 to 68), both within the standard deviation of the population mean of 50. CONCLUSION: The tibial turnup-plasty is a complex surgical option for patients with large bone defects of the femur for whom there are no alternative surgeries capable of producing residual extremities with acceptable functional length. This should be viewed as a procedure of last resort to avoid a hip disarticulation or a high transfemoral amputation in patients who have typically undergone numerous prior operations. Although ambulation with a prosthesis within 1 year can be expected, almost all patients will require an assistive device to do so, and reoperations are frequent. LEVEL OF EVIDENCE: Level IV, therapeutic study.