Myoepithelial Carcinoma of Soft Tissue: Report of Two Cases

CASE

A 40-year-old man was evaluated for a painful mass on his right calf, and a 36-year-old woman presented with a painless mass on her right foot. Final pathology revealed marked nuclear atypia and positivity for S100/SOX10 and AE1/AE3 confirming diagnoses of myoepithelial carcinoma. Both patients underwent surgical resection and are without evidence of local recurrence or metastatic disease at 1-year follow-up.

CONCLUSION

Soft-tissue tumors presenting in the extremities warrant careful evaluation and timely histopathologic diagnosis. Myoepithelial carcinomas are rare, aggressive tumors with a propensity for local recurrence and metastasis. Treatment of these tumors should be discussed by a multidisciplinary tumor team.

Hip Arthroplasty Outcomes in Patients with Metastatic Bone Disease

Background/Objective

The hip is a common location for metastatic bone disease (MBD) and surgical intervention is often indicated to relieve pain and improve function. MBD of the hip is usually treated with hemiarthroplasty or with total hip arthroplasty if there are acetabular lesions. As treatment for metastatic disease evolves and patients may expect to live longer after diagnosis, further evaluation of the complications and functional outcomes associated with hip arthroplasty for MBD are necessary.

Methods

This was a retrospective review of patients who underwent hip arthroplasty for MBD at a single institution between 2007 and 2021. Outcomes included rates of reoperation, complications, and overall survival.

Results

Ninety-three cases in 91 patients were included. Total hip arthroplasty (THA) was performed in 52 cases (55.9%), hemiarthroplasty in 15 (16.1%), and complex arthroplasty, including proximal femur replacement or THA with complex acetabular reconstruction, was performed in 26 (28%). There were 11 reoperations in five patients and six dislocations. Median survival was 10.4 months and one-year overall survival was 53.3%. There was a significant increase in the proportion of patients who were able to ambulate independently (35.2% vs 17.6%; p=0.02) and a significant decrease in patients confined to a wheelchair (18.7% vs 3.3%; p=0.045) after surgery.

Conclusions

Hip arthroplasty for MBD leads to relatively low rates of complications and reoperations in this population known to have high postoperative morbidity and mortality. Hip arthroplasty provides the majority of MBD patients with a durable reconstruction that exceeds their lifespan and enables them to return to an acceptable level of function.

Intra-Articular Nodular Fasciitis of the Knee, A Rare Clinical Presentation and Histological Diagnosis: A Case Report

Introduction

Nodular fasciitis is a rare, benign soft tissue lesion that can prove to be difficult to diagnose, especially when intra-articular.

Case presentation

A 17-year-old female softball player presents with several year history of right knee pain and swelling initially attributed to patellar maltracking refractory to non-operative and operative management.

Management and Outcomes

Initial pathology suggested tenosynovial giant cell tumor; however, further tissue diagnosis revealed nodular fasciitis, which was eventually resected.

Conclusion

Intra-articular nodular fasciitis of the knee is rare and may easily be misdiagnosed due to its nonspecific clinical presentation. Careful histological examination can aid in diagnosis. Nodular fasciitis should be considered in the differential diagnoses for intra-articular lesions of the knee joint.

Development and external validation of a machine learning model for prediction of survival in extremity leiomyosarcoma

PURPOSE

Machine learning (ML) models have been used to predict cancer survival in several sarcoma subtypes. However, none have investigated extremity leiomyosarcoma (LMS). ML is a powerful tool that has the potential to better prognosticate extremity LMS.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried for cases of histologic extremity LMS (n = 634). Patient, tumor, and treatment characteristics were recorded, and ML models were developed to predict 1-, 3-, and 5-year survival. The best performing ML model was externally validated using an institutional cohort of extremity LMS patients (n = 46).

RESULTS

All ML models performed best at the 1-year time point and worst at the 5-year time point. On internal validation within the SEER cohort, the best models had c-statistics of 0.75-0.76 at the 5-year time point. The Random Forest (RF) model was the best performing model and used for external validation. This model also performed best at 1-year and worst at 5-year on external validation with c-statistics of 0.90 and 0.87, respectively. The RF model was well calibrated on external validation. This model has been made publicly available at https://rachar.shinyapps.io/lms_app/ CONCLUSIONS: ML models had excellent performance for survival prediction of extremity LMS. Future studies incorporating a larger institutional cohort may be needed to further validate the ML model for LMS prognostication.

Development and external validation of a machine learning model for prediction of survival in undifferentiated pleomorphic sarcoma

PURPOSE

Machine learning (ML) algorithms to predict cancer survival have recently been reported for a number of sarcoma subtypes, but none have investigated undifferentiated pleomorphic sarcoma (UPS). ML is a powerful tool that has the potential to better prognosticate UPS.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried for cases of histologically confirmed undifferentiated pleomorphic sarcoma (UPS) (n = 665). Patient, tumor, and treatment characteristics were recorded, and ML models were developed to predict 1-, 3-, and 5-year survival. The best performing ML model was externally validated using an institutional cohort of UPS patients (n = 151).

RESULTS

All ML models performed best at the 1-year time point and worst at the 5-year time point. On internal validation within the SEER cohort, the best models had c-statistics of 0.67-0.69 at the 5-year time point. The Multi-Layer Perceptron Neural Network (MLP) model was the best performing model and used for external validation. Similarly, the MLP model performed best at 1-year and worst at 5-year on external validation with c-statistics of 0.85 and 0.81, respectively. The MLP model was well calibrated on external validation. The MLP model has been made publicly available at https://rachar.shinyapps.io/ups_app/ .

CONCLUSION

Machine learning models perform well for survival prediction in UPS, though this sarcoma subtype may be more difficult to prognosticate than other subtypes. Future studies are needed to further validate the machine learning approach for UPS prognostication.

Does Perioperative Radiation Affect Implant Survivorship of Primary Total Hip Arthroplasty in the Setting of Metastatic Bone Disease?

Background

Metastatic bone disease (MBD) commonly affects the hip and surgical intervention including total hip arthroplasty (THA) is often indicated to treat the joint and improve function. Patients with metastatic cancer often receive radiotherapy, and orthopaedic oncologists must consider surgical risks with operating on irradiated bone and soft tissue. We evaluated surgical outcomes and implant survival (IS) of titanium acetabular components and femoral components in patients treated for MBD in the setting of perioperative radiation.

Methods

This was a retrospective review of patients who underwent THA for MBD at 3 institutions between 2017 and 2021. Outcomes included rates of reoperation, complications, IS, and overall survival.

Results

Forty-six patients who received primary THA for MBD were included in the study. Twenty patients (43.5%) received perioperative radiation for MBD. Six postoperative complications including one superficial wound infection, 2 dislocations, 2 pathologic fractures, and one aseptic acetabular component loosening led to 5 reoperations. There were no significant differences in postoperative outcomes, reoperation after THA, and IS based on radiotherapy status.

Conclusions

To our knowledge, this is the first paper evaluating primary THA outcomes and IS between patients who receive perioperative radiation for MBD to the hip and those who do not. As surgical management is a crucial part of the treatment in alleviating pain and disability in patients with MBD, we continue to recommend THA for patients who received radiation at the operative site.

The effect of timing between preoperative embolization and surgery: A retrospective analysis of hypervascular bone metastases

BACKGROUND AND OBJECTIVES

The optimal timing between preoperative embolization of hypervascular metastatic bone lesions and surgery has yet to be established. Our analysis sought to evaluate embolization timing impacts blood loss, transfusion risk, and operative time in patients with hypervascular primary tumors.

METHODS

We identified patients with renal cell (RCC) or thyroid carcinoma undergoing surgery between 1992 and 2023. Patients were segregated into the following cohorts: (1) no embolization preoperatively, (2) surgery <24 h of embolization, and (3) surgery >24 h after embolization. Multivariate logistic regression analyses were performed to assess the effect of embolization timing while controlling for confounding variables.

RESULTS

No differences were seen in all evaluated outcomes between immediate and delayed embolization cohorts. No differences in estimated blood loss were seen between the immediate (OR: 0.685, 95% CI: 0.159-2.949; p = 0.611) and delayed (OR: 0.568, 95% CI: 0.093-3.462; p = 0.539) surgery cohorts compared with patients without embolization. Surgery >24 h after embolization was not associated with a higher risk of prolonged operative time (OR: 13.499, 95% CI: 0.832-219.146; p = 0.067).

CONCLUSIONS

These findings suggest that surgery may be safely delayed beyond 24 h from embolization without a higher risk of bleeding. In appropriately selected cohorts, embolization may not be needed preoperatively.

Rare Dedifferentiated Periosteal Chondrosarcoma with 11-Year Metastatic Relapse: A Case Report

A 50-year-old man presented for evaluation of a periscapular mass. Biopsy suggested a low-grade chondrosarcoma; however, the resected specimen revealed a grade 2 chondrosarcoma with a low-grade dedifferentiated mesenchymal component. The mass multiply recurred as chondrosarcoma without a dedifferentiated component before the patient developed lung metastases of chondrosarcoma without a dedifferentiated component 11 years after the initial diagnosis and died of disease. This is one of the first reported cases of a dedifferentiated chondrosarcoma with low-grade dedifferentiated component. While overall prognosis may be better than in typical dedifferentiated chondrosarcoma, this tumor demonstrated numerous local recurrences as well as metastasis.

An Unusual Case of Clear Cell Chondrosarcoma With Early Metastatic Recurrence

We present a case of a 58-year-old male who presented following 4 months of progressively worsening right upper extremity pain. Initial pathology demonstrated pleomorphic chondroblasts with increased mitotic activity indicating an intermediate grade (Grade 2) clear cell chondrosarcoma of the proximal humerus. Following surgical resection, the primary lesion demonstrated aggressive behavior and early metastasis to the cervical and thoracic spine. The patient unfortunately expired 30 months after initial presentation. Although clear cell chondrosarcoma has been historically regarded as low grade, we present a unique example of an aggressive clinical course of clear cell chondrosarcoma.

Evaluation of Absolute Neutrophil Count in the Perioperative Setting of Sarcoma Resection

Introduction

Limb salvage surgery (LSS) is the preferred surgical treatment for bone sarcomas. Preoperatively, many patients receive chemotherapy and may develop neutropenia. No study has evaluated the effect of a low preoperative absolute neutrophil count (ANC) on postoperative outcomes following LSS.

Methods

This was a retrospective review of 114 patients who underwent LSS for bone sarcoma from 2010 to 2020. Preoperative lab values were analyzed by logistic regression to identify the risk of developing surgical complications within 30 days, surgical site infection (SSI), and reoperation.

Results

Three (2.6%) patients experienced a surgical complication within 30 days. Twelve (10.53%) patients experienced postoperative SSI. Twenty-nine (25.4%) required reoperation. Preoperative ANC was not a significant predictor of surgical complications within 30 days, SSI, or reoperation. The only independent predictor of worse overall survival was the presence of a pathologic fracture at the time of surgery.

Conclusion

This is the first study to evaluate preoperative ANC on postoperative outcomes following LSS. We report no significant differences in surgical complications within 30 days, SSI, or reoperation with low preoperative ANC. Future studies with larger cohorts of neutropenic patients are needed to evaluate these outcomes, as our cohort had very few neutropenic patients due to selection bias.

Clinical Outcomes Following Resection of Distal Lower Extremity Soft Tissue Sarcomas

OBJECTIVE

Resection of soft tissue sarcoma (STS) in the distal lower extremity can result in large soft tissue defects that create difficult wounds to manage and significant risks for complications. Often, the anticipated or resultant tissue defect or loss of functional anatomy is an indication for amputation over limb salvage. Soft tissue reconstruction managed by plastic and reconstructive surgery (PRS) may help offer limb salvage as a therapeutic option with acceptable oncologic outcomes and wound complication rates.

METHODS

This was a review of 52 patients who underwent resection of STS at the level of the knee or distal between 2010 and 2020. Plastic and reconstructive surgery soft tissue management was utilized in 40.4% (n = 21) of cases, most of whom would have otherwise been considered candidates for amputation.

RESULTS

The overall rate of limb salvage was 76.9%. The overall rate of wound complications was 19.2%. The overall rate of negative margins of resection was 92.3%. The 1-, 5-, and 10-year overall survival probabilities were 92%, 85%, and 85%, respectively. Of the 40 limb salvage procedures, two required subsequent amputation, one for multiply recurrent disease and one for necrosis. The wound complication rate was 14.3% in the PRS management group and 22.6% in cases of wound closure managed by the primary surgeon. There were zero instances of total wound or flap loss in PRS- managed closures. When comparing patients with wound complications to those without, there was no difference in age (59.5 ± 21 vs. 51 ± 18 years, p = 0.42), body mass index (31.1 ± 4.8 vs. 26.1 ± 7.1 kg/m2 , p = 0.19), or tumor size (6.8 ± 5.0 vs. 6.4 ± 4.7 cm, p = 0.82). At final follow-up, 67% (n = 35) of patients were alive and disease-free.

CONCLUSIONS

Wound complications are not uncommon after resection of distal lower extremity STS. Our experience has been successful in achieving limb salvage in these challenging cases. Without PRS soft tissue management, however, many patients may alternatively be candidates for amputation.

Total Knee Arthroplasty for Osteoarthritis Is Uncommon after Intralesional Curettage in Giant Cell Tumor of Bone

Giant cell tumor of bone (GCTB) is most often treated with intralesional curettage; however, periarticular lesions have been shown to increase risk for osteoarthritis. Additionally, the location of these lesions may occasionally preclude a joint-sparing procedure in recurrent tumors. This study sought to investigate rates of secondary arthroplasty in long-term follow-up of knee GCTB. Cases of knee GCTB treated at our institution were reviewed. Rates of recurrence and secondary arthroplasty were recorded, and Kaplan-Meier survival analyses were performed. The records of 40 patients were reviewed. Local recurrence occurred in 25% of patients. The 1-, 5-, and 10-year recurrence-free survival (RFS) probability was 87.4% (95% CI, 77.0-97.7), 72.4% (95% CI, 57.6-87.2), and 72.4% (95% CI, 57.6-87.2), respectively. Function improved after surgery with a mean preoperative MSTS score of 14.9 (standard deviation [SD] 8.4) and mean postoperative MSTS score of 25.1 (SD 5.6) (p <0.001). Three patients had evidence of radiographic osteoarthritis at the last follow-up though they did not require arthroplasty. Arthroplasty was performed as a secondary procedure in six patients. Five patients underwent arthroplasty for recurrent tumors after initial treatment with curettage and one patient underwent patellar arthroplasty for osteoarthritis after initial treatment with an allograft composite arthroplasty. Arthroplasty is performed as a secondary procedure in patients with GCTB at a relatively infrequent rate and more often for cases of recurrent disease than for osteoarthritis. Overall, patients treated for GCTB have improved functional outcomes after surgery than before. Large, multi-institutional studies may be required to assess the incidence of secondary osteoarthritis requiring arthroplasty as this was an infrequent finding in our cohort.

Opiate use after total hip arthroplasty for metastatic bone disease

OBJECTIVES

To investigate post-operative opioid use following a total hip arthroplasty (THA) in metastatic bone disease (MBD) patients and identify factors associated with post-operative opioid use at 6 weeks and 90 days.

BACKGROUND

MBD commonly affects the hip, and surgical intervention including THA may be indicated for pain relief or to improve function. Following THA, patients are often prescribed short courses of opioids for post-operative pain relief. No study has evaluated opiate use following THA in patients for MBD.

METHODS

This was a retrospective review of patients using opioids preoperatively who underwent primary THA for MBD at two institutions between 2009 and 2022. Preoperative and post-operative opioid usages, respectively, at 6 weeks and 90 days were quantified through calculating daily morphine milligram equivalents (MMEs) and compared using the sign test. Factors associated with post-operative opioid use at 6 weeks and 90 days were compared using χ2 test or Fisher's exact test as appropriate.

RESULTS

Nineteen THA and 11 THA with complex acetabular reconstruction were included. At 6 weeks, 26 (86.7 percent) patients were utilizing opiates, and at 90 days, 23 (76.7 percent) patients were utilizing opiates. There was a statistically significant difference between median daily preoperative MME compared to daily MME at 90 days (p < 0.001). The only statistically significant association with opioid use at 90 days was opioid use at 6 weeks.

CONCLUSION

To our knowledge, this is the first paper evaluating post-operative opioid use following primary THA in MBD patients. After THA in the setting of MBD, patients exhibit decreased post-operative opioid use. Future studies with larger cohorts should be conducted to characterize post-operative opioid use following joint arthroplasty in MBD patients.

Radiation osteitis: incidence and clinical impact in the setting of radiation treatment for soft tissue sarcoma

OBJECTIVE

Radiotherapy is an important component of soft tissue sarcoma management. Radiation osteitis is a common radiographic finding identified in the setting of radiotherapy on magnetic resonance imaging (MRI). This study aims to identify the incidence of radiation osteitis in patients who received radiotherapy for soft tissue sarcoma and if a further workup, including a biopsy, was performed for concerning MRI findings.

MATERIALS AND METHODS

Medical records of patients with soft tissue sarcoma who received radiotherapy from 2008 to 2020 were retrospectively reviewed. Patients with at least one MRI of the sarcoma site following radiotherapy and information regarding radiotherapy treatments were included. MRIs of these patients were reviewed for the presence of radiation osteitis by two musculoskeletal radiologists. The clinical course of these patients including biopsy for concerning MRI findings, local recurrence, and metastasis was recorded.

RESULTS

Thirty soft tissue sarcoma patients who received radiation for soft tissue sarcoma were included. Radiation osteitis was present in 18 patients. The time to osteitis present on MRI following radiotherapy completion was a median of 4.5 months. Biopsy for concerning MRI findings was performed in eight patients, five for local recurrence, and three for regional osseous metastasis. Three patients had confirmed osseous metastases.

CONCLUSION

Although radiation osteitis is often a benign imaging finding, it can be difficult to discern these lesions from potentially malignant sites of disease. We recommend multidisciplinary management of soft tissue sarcoma at sarcoma centers to appropriately identify benign from malignant lesions and decide the necessity of a biopsy.

Patient-reported outcome tools in musculoskeletal oncology

Patient-reported outcomes (PRO) are collected directly from the patient and have become increasingly utilized in the clinical setting and in clinical research. In musculoskeletal oncology patients, a number of patient-reported outcomes measures (PROM) have been developed and investigated to evaluate functional outcomes and health-related quality of life in these patients. With the growing evidence for PROM in musculoskeletal oncology patients, PROM should be considered for the clinical care of these patients.

Radiolucent implants in orthopedic oncology

Radiolucent implants in have demonstrated promising results for both extremity and spine oncologic procedures. However, questions persist about whether the superiority in surveillance imaging justify the increased cost and technical challenges. In this review, we present the current body of literature for the use of radiolucent implants in musculoskeletal oncology, with a focus on implant complications, including screw loosening, breakage, malposition, and loss of reduction. We also discuss clinical outcomes, technical considerations, and postoperative radiotherapy.

The First Cold Atmospheric Plasma Phase I Clinical Trial for the Treatment of Advanced Solid Tumors: A Novel Treatment Arm for Cancer

Local regional recurrence (LRR) remains the primary cause of treatment failure in solid tumors despite advancements in cancer therapies. Canady Helios Cold Plasma (CHCP) is a novel Cold Atmospheric Plasma device that generates an Electromagnetic Field and Reactive Oxygen and Nitrogen Species to induce cancer cell death. In the first FDA-approved Phase I trial (March 2020-April 2021), 20 patients with stage IV or recurrent solid tumors underwent surgical resection combined with intra-operative CHCP treatment. Safety was the primary endpoint; secondary endpoints were non-LRR, survival, cancer cell death, and the preservation of surrounding healthy tissue. CHCP did not impact intraoperative physiological data (p > 0.05) or cause any related adverse events. Overall response rates at 26 months for R0 and R0 with microscopic positive margin (R0-MPM) patients were 69% (95% CI, 19-40%) and 100% (95% CI, 100-100.0%), respectively. Survival rates for R0 (n = 7), R0-MPM (n = 5), R1 (n = 6), and R2 (n = 2) patients at 28 months were 86%, 40%, 67%, and 0%, respectively. The cumulative overall survival rate was 24% at 31 months (n = 20, 95% CI, 5.3-100.0). CHCP treatment combined with surgery is safe, selective towards cancer, and demonstrates exceptional LRR control in R0 and R0-MPM patients. (Clinical Trials identifier: NCT04267575).

A Rare Location of Osteosarcoma in the Cuboid Bone: A Case Report

CASE

In this case report, we describe a patient with left foot pain whose magnetic resonance imaging revealed a destructive tumor of the left cuboid bone. A biopsy of the tumor confirmed an osteoblastic osteosarcoma of the cuboid, and the patient was treated with chemotherapy followed by a below-the-knee amputation.

CONCLUSION

There are only a handful of cases reporting osteosarcoma of the cuboid bone, and challenges remain in properly diagnosing the lesion to recommend the best course of treatment.

Evaluation of Local Recurrence and Diagnostic Discordance in Chondrosarcoma Patients Undergoing Preoperative Biopsy

BACKGROUND/AIM

Preoperative biopsy of chondroid lesions has demonstrated discordance between biopsy grade and surgical resection grade. Furthermore, there is evidence to suggest risk of tumor contamination during biopsy. We evaluated our large chondrosarcoma institutional cohort to compare the rates of local recurrence based on pre-surgical biopsy, as well as other tumor characteristics and disease-related outcomes.

PATIENTS AND METHODS

This was a retrospective review of patients who underwent surgical resection for chondrosarcoma at our Institution between 2005 and 2020. Outcomes included rates of local recurrence, metastasis, and overall survival.

RESULTS

No significant differences were found in local recurrence and recurrence-free survival in cases of pre-operative biopsy. Thirteen (28.2%) patients had discordance between histological grade on biopsy and resection. Seven (63.6%) patients with dedifferentiation present on final resection were not identified on biopsy. The only independent predictor of recurrence-free survival and metastasis-free survival was the presence of dedifferentiation on resection.

CONCLUSION

To our knowledge, this is the first study evaluating risk of local recurrence in the setting of pre-surgical biopsy in chondrosarcoma patients. Although pre-operative biopsy may contaminate biopsy tracts, appropriate surgical planning and final resection results in no difference in local recurrence rates in this cohort. However, discordance rates between preoperative biopsy and resected specimen must be considered while determining clinical treatment.

Association between neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and survival in undifferentiated pleomorphic sarcoma (NLR, PLR, and overall survival in UPS)

BACKGROUND AND OBJECTIVES

Cancer-related inflammation has been shown to be a driver of tumor growth and progression, and there has been a recent focus on identifying markers of the inflammatory tumor microenvironment. Neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) are inflammatory indices that have been identified as prognostic biomarkers in various malignancies. However, there is limited and conflicting data regarding their prognostic value in soft tissue sarcoma (STS) and specifically in undifferentiated pleomorphic sarcoma (UPS).

METHODS

This was a retrospective review of patients who underwent surgical treatment for primary UPS from 1993 to 2021. Cutoff values for NLR and PLR were determined by receiver operating curve analysis. Cox proportional hazards regression was used to determine prognostic factors on univariate and multivariate analysis.

RESULTS

Eighty-six patients were included. The optimal cutoff value was 3.3 for NLR and 190 for PLR. Both high NLR (HR 2.44; 95% CI 1.29-4.63; p = 0.005) and high PLR (HR 1.99; 95% CI 1.08-3.67, p = 0.02) were associated with worse OS on univariate analysis. On multivariate analysis, metastasis at presentation and radiotherapy were independently predictive of OS, but high NLR (HR 1.30; 95% CI 0.64-2.98; p = 0.41) and high PLR (HR 1.63; 95% CI 0.82-3.25; p = 0.17) were not predictive of survival.

CONCLUSIONS

High pre-treatment NLR and PLR were associated with decreased overall survival but were not independent predictors of survival in patients undergoing resection for UPS. Until additional prospective studies can be done, survival outcomes are best predicted using previously established patient- and tumor-specific factors.

Minimally invasive management of pathologic fractures of the pelvis and sacrum: Tumor ablation and fracture stabilization

BACKGROUND

Pathologic fractures of the pelvis/sacrum due to metastatic bone disease (MBD) cause pain and dysfunction due to mechanical instability of the pelvic ring. This study presents our multi-institutional experience with percutaneous stabilization of pathologic fractures and osteolytic lesions from MBD throughout the pelvic ring.

METHODS

The records of patients undergoing this procedure from 2018 to 2022 were reviewed retrospectively from two institutions. Surgical data and functional outcomes were recorded.

RESULTS

Fifty-six patients underwent percutaneous stabilization, with a median operative duration of 119 min (interquartile range [IQR]: 92.8, 167) and median estimated blood loss of 50 mL (IQR: 20, 100). The median length of stay was 3 days (IQR: 1, 6), and 69.6% (n = 39) of patients were discharged home. Early complications included one partial lumbosacral plexus injury, three acute kidney injuries, and one case of intra-articular cement extravasation. Late complications included two infections and one revision stabilization procedure for hardware failure. Mean Eastern Cooperative Oncology Group (ECOG) scores improved from 3.02 (SD 0.8) preoperatively to 1.86 (SD 1.1) postoperatively (p < 0.001). Ambulatory status also improved (p < 0.001).

CONCLUSIONS

Percutaneous stabilization of pathologic fractures and osteolytic defects of the pelvis and sacrum is a procedure that improves patient function, ambulatory status and is associated with a limited complication profile.

Single-Stage Revision of Infected Total Femoral Replacement

We present 2 cases of infected total femur prosthetic devices treated with a single-stage revision with extensive irrigation and debridement, followed by reimplantation with a prosthesis coated in antibiotic-impregnated cement. Single-stage total femoral replacement with antibiotic-eluting cement around the device was used for 2 cases of limb salvage arthroplasty to reduce complications, maintain patient function, and minimize hospital-associated cost. [Orthopedics. 2022;45(5):e280-e283.].

Radiotherapy, volume reduction, and short-term surgical outcomes in the treatment of large myxoid liposarcomas

Purpose

While tumor volume reduction following radiation has been documented in myxoid liposarcomas, it is unclear whether large tumors experience similar volume reduction to smaller tumors.

Materials and Methods

MRI studies performed before and after completion of pre-operative radiation therapy (RT) were examined. Tumor sizes were noted and categorized as large versus small based on size >10 cm. Tumor volumes were calculated, and operative duration and major wound complications were recorded.

Results

The median largest tumor dimension was 12.4 cm before RT and 8.7 cm after RT. The median tumor volume was 298.9 cm3 before RT and 106.9 cm3 after RT. There was no significant difference in the mean percent tumor volume reduction between large tumors and small tumors (p = 0.11, 56.3% vs. 64.5%). Operative duration most strongly correlated to post-RT MRI volume (R2=0.674, p<0.001). Despite volume reduction, tumors that were large on presentation were more likely to experience major wound complications post-operatively.

Conclusion

Radiation appears to be as effective at reducing myxoid liposarcoma tumor volume in large and small tumors. However, large tumors on presentation appear more likely to experience wound complications despite tumor volume reduction. Future studies should investigate disease-related outcomes as a factor of volume reduction in myxoid liposarcoma.

External validation of machine learning models for prediction of survival in undifferentiated pleomorphic sarcoma

e13551

Background: Machine learning (ML) algorithms to predict cancer survival have recently been reported for a number of sarcoma subtypes, but none have investigated undifferentiated pleomorphic sarcoma (UPS). ML is a powerful tool that has the potential to better prognosticate UPS. Methods: The Surveillance, Epidemiology, and End Results (SEER) database was queried from 2004 to 2015 for cases of histologically confirmed undifferentiated pleomorphic sarcoma (UPS) and malignant fibrous histiocytoma (MFH). Patient, tumor, and treatment characteristics were recorded, and various machine learning (ML) models were built to predict 1-, 3-, and 5-year survival. The best performing ML models were externally validated using an institutional cohort of UPS patients. Results: All ML models performed best at the 1-year time point and worst at the 5-year time point. On internal validation within the SEER cohort, the best models had c-statistics of 0.71 to 0.73 at the 5-year time point. Similarly, all ML models performed best at 1-year and worst at 5-year on external validation. The best performing models had c-statistics of 0.81 at the 5-year time point on external validation, demonstrating good performance in survival prediction. Conclusions: Machine learning models perform well for survival prediction in UPS, though this sarcoma subtype may be more difficult to prognosticate than other subtypes. Future studies are needed to further validate the machine learning approach for UPS prognostication. [Table: see text]

Radiotherapy, volume reduction, and short-term surgical outcomes in the treatment of large myxoid liposarcomas

e23546

Background: While tumor volume reduction following radiation has been documented in myxoid liposarcomas, it is unclear whether large tumors experience similar volume reduction to smaller tumors. Methods: MRI studies performed before and after completion of pre-operative radiation therapy (RT) were examined. Tumor sizes were noted and categorized as large vs. small based on size > 10 cm. Tumor volumes were calculated, and operative duration and major wound complications were recorded. Results: The median largest tumor dimension was 12.4 cm before RT and 8.7 cm after RT. The median tumor volume was 298.9 cm3 before RT and 106.9 cm3 after RT. There was no significant difference in the mean percent tumor volume reduction between large tumors and small tumors (p = 0.11, 56.3% vs. 64.5%). Operative duration most strongly correlated to post-RT MRI volume (R2= 0.674, p < 0.001). Despite volume reduction, tumors that were large on presentation were more likely to experience major wound complications post-operatively. Conclusions: Radiation appears to be as effective at reducing myxoid liposarcoma tumor volume in large and small tumors. However, large tumors on presentation appear more likely to experience wound complications despite tumor volume reduction. Future studies should investigate disease-related outcomes as a factor of volume reduction in myxoid liposarcoma.[Table: see text]

Dedifferentiated Chondrosarcoma: A Case Series and Review of the Literature

BACKGROUND

Dedifferentiated chondrosarcoma (DCS) is a rare and aggressive malignancy with a poor prognosis. The purpose of this investigation was to describe our treatment and outcomes of 16 DCS patients at our institution and provide a review of the current literature.

METHODS

This study was a retrospective review over a consecutive twenty-year period. Data including treatment details and outcomes were recorded.

RESULTS

A total of 16 cases from 2000 to 2018 were identified. The median age (IQR) was 62 years (52; 69) and the majority of DCS arose in the femur (50%, n=8) and pelvis (25%, n=4). Fourteen (88%) cases underwent limb salvage/wide margin resection (n=13) or intralesional surgery (n=1). For all DCS, the median survival (IQR) was 46 months (12; 140), with both a five and ten-year probability of 32.1% (95% CI, 7.3% to 57.0%). At study conclusion, 81.3% (n=13) were deceased and 18.7% (n=3) were alive.

CONCLUSIONS

Our findings confirm the poor prognosis of DCS patients, with a five-year estimate of 32%. Together with existing literature, our data might help enable future strategic recommendation of these patients.

En Bloc Resection of Giant Cell Tumor following Neoadjuvant Denosumab: A Case Report and Review of the Literature

Introduction

The RANK ligand inhibitor denosumab has been used to treat cases of unresectable giant cell tumors of bone (GCTB) or preoperatively to facilitate intralesional curettage. However, there are no clear guidelines for use of denosumab prior to en bloc resection.

Case Presentation

In this study, a 26-year-old patient presented with atraumatic lateral knee pain. X-rays demonstrated a destructive lesion within the proximal fibula, and biopsy confirmed the diagnosis of GCTB.

Management and Outcomes

The patient received 3 months of neoadjuvant denosumab with complete resolution of his pain and cortical rim formation surrounding the tumor. The tumor was removed en bloc with negative margins. At 6-month follow-up, the patient had returned to his functional baseline with no evidence of tumor recurrence.

Conclusion

Neoadjuvant denosumab can mitigate symptoms related to GCTB and promotes cortical bone formation, facilitating en bloc resection and permitting acceptable functional outcomes in select cases.

What factors are important to new patients when selecting an orthopedic oncologist?

BACKGROUND

Understanding how patients choose a provider may improve the overall experience by identifying ways to tailor a clinical practice.

AIM

To identify factors that patients consider important when choosing an orthopedic oncologist.

METHODS

New patients presenting to an orthopedic oncology clinic within a tertiary academic medical center from January 2019 to August 2020 were invited to complete an anonymous survey. The questionnaire consisted of 27 items including a Likert-type assessment of the importance of selection factors.

RESULTS

A total of 101 new patients with a median age of 66 years (range, 14 years to 91 years) responded. Most were referred by another doctor (n = 63, 62.4%), and of the referring providers, the most frequent specialty was orthopedic surgery (n = 32, 51%). Using a Likert-type scale with 1 representing ‘least important’ and 5 representing ‘most important’, the most important factor was the hospital reputation (mean, 4.65; SD, 0.85). Additional factors of importance were the number of years in practice (3.87 ± 1.3) and a primary care provider referral (3.71 ± 1.6). Patients younger than 40 years old found social media (P = 0.016) and internet presence (P = 0.035) of their surgeon to be more important than older patients. In contrast, older patients considered care within an academic center to be of greater importance than younger patients (P = 0.014).

CONCLUSION

This investigation suggests a primary care referral, as well as hospital and physician reputation, are among the most important factors when selecting an orthopedic oncologist. Furthermore, social media utilization appears to be more important for younger patients.

Indication for Proximal Femoral Replacement Is Associated With Risk of Failure

BACKGROUND

Proximal femoral replacement (PFR) is reserved as a salvage procedure after failed total hip arthroplasty (THA) or after wide margin resection of tumors involving the proximal femur. Although failure of the PFR construct remains a significant problem, indication has not previously been investigated as a risk factor for failure.

METHODS

This study retrospectively evaluated patients who underwent PFR over a consecutive 15-year period for primary sarcoma or metastatic disease of the proximal femur, compared with conversion to PFR after failed THA. PFR failure was defined as recurrent prosthetic dislocations, periprosthetic fracture, aseptic loosening, or infection that ultimately resulted in revision surgery.

RESULTS

Overall, 99 patients were evaluated, including 58 in the neoplasm and 41 in the failed THA cohorts. Failed THA patients were older (P < .001), with a greater proportion having comorbid hypertension (P = .008), cardiac disease (P = .014), and history of prior ipsilateral and intracapsular surgeries (P < .001). The failure rate was significantly higher in failed THA patients (39.0% vs 10.3%; P < .001) with significantly shorter implant survivorship on Kaplan-Meier analysis (P = .003). A multivariate Cox proportional hazards model showed that THA failure was the only independent predictor for PFR failure (hazard ratio: 4.26, 95% confidence interval: 1.66-10.94; P = .003).

CONCLUSION

This study revealed significantly worse PFR implant survivorship in patients undergoing PFR for the indication of failed THA compared with neoplasm. Although the underlying etiology of this relationship remains to be explicitly outlined, poor bone quality and soft tissue integrity, multiple prior surgeries, and comorbid conditions are likely contributing factors.

High-Grade B-Cell Lymphoma of the Sciatic Nerve That Mimicked a Schwannoma: A Case Report

CASE

A 41-year-old woman with a history of high-grade B-cell lymphoma status-post chemotherapy was evaluated for a painful left posterior thigh mass and significant weakness with sensory changes. Imaging revealed a benign-appearing mass consistent with schwannoma; however, intraoperative frozen section suggested high-grade B-cell lymphoma. Subsequent restaging studies revealed metastatic disease.

CONCLUSION

A history of lymphoma warrants careful investigation of a posterior thigh mass, despite imaging findings consistent with nerve sheath tumor. Surgical removal of lymphomas of the nerve often proves futile, so these lesions are usually managed with medical treatment or radiation.

Extraskeletal myxoid chondrosarcoma: A case series and review of the literature

Background

Extraskeletal myxoid chondrosarcoma (EMC) is a rare malignant soft tissue sarcoma (STS) that accounts for less than 3% of all soft tissue tumors. The conventional treatment for primary EMC is wide local excision with or without radiation therapy.

Materials and Methods

This study was a retrospective review of all EMC cases treated within a single institution between 1992 and 2019. EMC was diagnosed using a combination of histologic morphology and immunostaining, with confirmatory fluorescent in situ hybridization. Overall survival (OS) and disease-specific survival (DSS) were defined using Kaplan–Meier analysis.

Results

Fifteen patients were evaluated, including 11 males and four females. The average age at presentation was 51.7 ± 20.4 years and the mean follow-up time was 61.5 months (range, 5–286 months). The average resected tumor size at largest dimension was 7.14 cm (range, 2.4–18.7). Twelve of fifteen (80%) patients underwent wide local excision, and nine of the twelve (75%) underwent local radiation therapy. The 1-, 5-, and 10-year OS was 80% (95% CI, 59.8–100), 72% (95% CI, 48.5–95.5), and 72% (95% CI, 48.5–95.5), respectively. The 1-, 5-, and 10-year DSS was 92.3% (95% CI, 77.8–100), 83.1% (95% CI, 61.5–100), and 83.1% (95% CI, 61.5–100), respectively. At last follow-up, 11 patients were alive and ten (90.9%) were disease free.

Conclusions

Extraskeletal myxoid chondrosarcoma is a very rare STS most often seen in males and in the extremities. Our cohort was too small to provide meaningful statistical analysis; however, we observed lower rates of local recurrence in patients treated with radiation.

3D-Printed Cutting Guides for Resection of Long Bone Sarcoma and Intercalary Allograft Reconstruction

The use of 3-dimensional (3D)-printed cutting guides for resection of long bone sarcoma is a novel technique. These 3D-printed guides provide a potential benefit over navigational or freehand osteotomy. We evaluated whether the use of 3D-printed cutting guides in the resection of long bone sarcoma affects margin status and rates of union compared with historical controls. In this study, we performed a retrospective review of a prospectively maintained surgical database and reviewed 6 patients who underwent limb salvage for long bone sarcoma. We collected and analyzed clinicopathologic and surgical data. Six (100%) cases recorded negative margins, with mean postoperative follow-up of 108 weeks (range, 8-211 weeks). Time (mean±SD) to bony union was 20.5±10.5 weeks. Nine of 12 (75%) cumulative (proximal and distal) osteotomy sites went on to achieve union, with a nonunion rate of 25% per osteotomy. One (33%) nonunion occurred after adjuvant radiation therapy. Long-term complications were limited to 2 (33.3%) patients overall who had implant failure according to the Henderson classification system, and there were zero local recurrences at the conclusion of the study. Our institution has successfully performed limb salvage surgery with patient-specific 3D-printed technology. We show high rates of negative margin resection and junctional union that align with and improve on earlier findings. [Orthopedics. 2022;45(1):e35-e41.].

What is the clinical impact of staging and surveillance PET-CT scan findings in patients with bone and soft tissue sarcoma?

BACKGROUND AND OBJECTIVES

Positron emission tomography-computerized tomography (PET-CTs) are becoming increasingly utilized in sarcoma care, workup, and surveillance. This study aimed to describe additional PET-CT findings as well as subsequent workups and changes in the clinical course due to those results.

METHODS

Patient records were retrospectively reviewed, and the additional workups and evaluations triggered by PET-CT findings were qualitatively analyzed to document their results. Additional changes in the clinical course were documented.

RESULTS

A total of 183 bone and soft tissue sarcoma patients underwent PET-CT as part of staging or surveillance. Additional workup was performed in 31.5% (n = 41 of 130) patients who had positive PET-CT findings. Among these, 36.6% (n = 15 of 41) patients had clinically significant findings that altered the clinical course. Overall, 14.8% (n = 27 of 183) experienced a change in the clinical course due to PET-CT.

CONCLUSION

PET-CT often highlights lesions of potential clinical importance. Additional workup, as well as changes in the clinical course, were not infrequent. Future, multi-institutional studies should address the value of PET-CT in sarcoma care.

Tumors and Tumorlike Conditions of Which Every Orthopaedic Surgeon Should Be Aware

All orthopaedic surgeons during the course of their career will likely encounter both benign and malignant musculoskeletal neoplasms. Given the rarity of these entities and the stress conferred by diagnosing a tumor or tumorlike condition, many orthopaedic surgeons may benefit from a review of the contemporary treatment of such patients. Whether in the outpatient clinic or following a high-energy trauma, special attention should be given to concerning signs and symptoms that will aid in the workup of children and adults with a possible tumor. A thorough and logical workup in this manner will often lead to a definitive diagnosis such as metastatic bone disease or perhaps a benign lesion. In these instances, the informed general orthopaedic surgeon or subspecialist may choose to treat the patient independently. However, if the workup is inconclusive or if the diagnosis is even questionably malignant, referral to an orthopaedic oncologist should be sought as to avoid pitfalls in diagnosis and treatment.

The clinical utility of next-generation sequencing for bone and soft tissue sarcoma

Background: Sarcomas are a rare and heterogeneous tumor group composed of a variety of histologic subtypes. Targeted next-generation sequencing (NGS) of bone and soft tissue sarcomas is a nascent field with limited evidence for its use within clinical practice. Therefore, further research is needed to validate NGS in sarcoma and assess the clinical utility of these techniques with the hope of improving treatment options.Methods: Comprehensive molecular profiling with NGS was performed on 136 tumors (116 soft tissue, 20 bone) using two commercial vendors. Patient records were retrospectively reviewed, and the clinical impact of NGS-related findings were qualitatively analyzed to determine actionable mutations and number of changes in treatment.Results: The median age was 55.0 years (IQR 42-67 years), and most patients were non-metastatic at presentation (80.9%, n = 110). Prior to performing NGS, 72.1% (n = 98) were treated with a mean 1.1 ± 1.2 lines of systemic chemotherapy. NGS identified 341 putative alterations with at least one mutation present in 89.7% (n = 122) of samples. In a subset of 111 patients with available TMB data, 78.7% (n = 107) had a low (<6 m/Mb) mutational burden. Among all 136 cases, 47.1% (n = 64) contained clinically actionable alterations, and 12 patients had a change in medical treatment based on NGS. Those who underwent a treatment change all had metastatic or recurrent disease; three of these patients experienced a clinical benefit.Conclusion: Most bone and soft tissue sarcomas harbor at least one genetic alteration, and it appears a sizeable number of tumors contain mutations that are clinically actionable. While a change in treatment based off NGS-related findings occurred in 12 cases, three patients experienced a clinical benefit. Our data provide further proof-of-concept for NGS in sarcoma and suggest a clinical benefit may be observed in select patients.

Internal fixation versus endoprosthetic replacement of the proximal femur for metastatic bone disease: Single institutional outcomes

PURPOSE

This study compared internal fixation (IF) to proximal femur replacement (PFR) for proximal femoral metastasis.

METHODS

Between 2005 and 2019, 113 lesions underwent IF (n = 94) or PFR (n = 19). Revision risk was calculated with mortality as a competing event.

RESULTS

The 5-year revision risk after IF was 17.6% (95% CI, 9.8%-27.3%) compared to 7.6% (95% CI, 0.3%-28.9%) after PFR (p = 0.59). PFR had longer operative times (p < 0.001), hospital stay (p = 0.039), and higher blood loss (p < 0.001) than IF, respectively.

CONCLUSIONS

IF may be considered for patients with poor health and a limited prognosis given the less-invasive procedure and shorter hospital stay.

LEVEL OF EVIDENCE

III. Retrospective Study.

Comparison of Features and Outcomes of Undifferentiated Pleomorphic Sarcoma of Bone and Soft Tissue

BACKGROUND

This investigation compared outcomes of patients with undifferentiated pleomorphic sarcoma of soft tissue (UPS-S) to UPS of bone (UPS-B).

METHODS

The Surveillance, Epidemiology, and End Results database was reviewed from 1975-2016. Disease-specific survival (DSS) was estimated using Kaplan-Meier, and a multivariable Cox regression model identified factors prognostic of DSS. The UPS-S cohort consisted of 4529 patients and the UPS-B cohort consisted of 200 patients. The smaller UPS-B cohort was bootstrapped to create a size-matched cohort of 4500 patients.

RESULTS

The median age of patients with UPS-S was 67 (54;78) y compared to 55 (40;69) y for UPS-B patients (P < 0.001). For UPS-S, the median DSS was 317 mo compared to 70 for UPS-B (P = 0.020). On multivariable analysis for UPS-S, age (HR, 1.018; 95% CI, 1.01-1.03; P < 0.001), non-extremity tumors (HR, 1.490; 95% CI 1.14-1.95; P = 0.004), and AJCC Stage III (HR, 2.238; 95% CI 1.2-4.17; P = 0.011), and Stage IV (HR, 9.388; 95% CI 4.69-18.79; P < 0.001) disease were negative prognostic factors, while surgery (HR 0.234; 95% CI, 0.16-0.34; P < 0.001) was a positive prognostic factor. For UPS-B, tumor size > 8 cm (HR, 3.101; 95% CI, 1.09-8.75; P = 0.033) was the only prognostic factor identified.

CONCLUSIONS

The current study found a strong association between surgery and survival for UPS-B patients on a univariable analysis, but no treatment type was associated with survival in a multivariable model. Further research is needed to reliably inform the optimal treatment of these patients.

Pulmonary metastasectomy in bone and soft tissue sarcoma with metastasis to the lung

 

OBJECTIVES

This study investigated the outcomes of sarcoma patients with lung metastases who underwent pulmonary metastasectomy (PM), compared to patients who underwent medical management alone. The secondary objective was to compare survival after PM between variables of interest.

METHODS

This was a retrospective review of 565 sarcoma patients with confirmed, isolated pulmonary metastasis identified from the Surveillance, Epidemiology and End Results database between 2010 and 2015. 1:4 propensity score matching was used to select PM and non-PM groups. The multivariable Cox proportional hazards model was used to analyse prognostic factors of disease-free survival (DFS).

RESULTS

Of the eligible 565 patients, 59 PM patients were matched to 202 non-PM patients in a final ratio of 3.4. After propensity matching, there were no significant differences in baseline characteristics between PM and non-PM patients. The median DFS after PM was 32 months (interquartile range 18–59), compared to 20 months (interquartile range 7–40) in patients without PM (P = 0.032). Using a multivariable Cox proportional hazards model, metastasectomy (hazard ratio 0.536, 95% confidence interval 0.33–0.85; P = 0.008) was associated with improved DFS. In a subset analysis of patients who underwent PM only, the median DFS was longer in males compared to females (P = 0.021), as well as in bone sarcoma compared to soft tissue sarcoma (P = 0.014).

CONCLUSIONS

For sarcoma patients with metastatic lung disease, PM appears to improve the prognosis compared to medical management. Furthermore, there may be a survival association with gender and tumour origin in patients who underwent PM. These data may be used to inform the surgical indications and eligibility criteria for metastasectomy in this setting.

Outcomes of brain metastasis in high-grade bone and soft tissue sarcoma: An analysis of clinicopathological characteristics and survival data

Brain metastases in sarcoma are exceedingly rare, with few published series documenting ranges from 1% to 8%. This study investigated the outcomes of sarcoma patients with brain metastases using a population-based analysis. This was a retrospective review of 5933 patients with high-grade sarcoma identified from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Of the eligible 5933 patients, 0.7% (n = 44) had brain metastasis. Kaplan–Meier was used to estimate survival and follow-up (reverse Kaplan–Meier), and a multivariable Cox proportional hazards model analyzed prognostic factors of disease-free survival (DFS). Median (IQR) follow-up of all eligible patients was 28 months (12; 47). Patients who developed brain metastasis had a higher proportion of N1 stage disease (p < 0.001), as well as synchronous metastasis to bones, liver, and lungs compared to those without brain metastasis (all p < 0.001). The median (IQR) DFS with brain metastasis was 6 months (2; 12), and survival with brain metastasis was significantly worse than DFS in patients without brain metastasis (p < 0.001). Among those with brain metastasis only, there was no difference in DFS with respect to sex, race, primary tumor origin, T stage or N stage disease, synchronous metastasis to bone, liver or lung, nor with respect to chemotherapy or radiation for treatment of the primary tumor (all p > 0.05). For sarcoma patients with brain metastasis, the outcomes are poor and do not appear to differ by clinicopathologic factors. However, patients with certain histologies and synchronous metastases may warrant more frequent surveillance as there was an association of brain metastasis with these factors.

Dedifferentiated chondrosarcoma: A report of the clinicopathologic features and outcomes of 16 cases treated at a single institution

e23500

Background: Dedifferentiated chondrosarcoma (DCS) is a rare and aggressive malignancy with a poor prognosis. The purpose of this investigation was to assess the clinicopathological features and outcomes of DCS patients treated at a single institution. Methods: This study was a retrospective review over a consecutive twenty-year period. Data including treatment details and outcomes were recorded. Results: A total of 16 cases from 2000 to 2018 were reviewed. The median age was 62 years (IQR, 52-69 years) and the majority of DCS arose in the femur (50%, n = 8) and pelvis (25%, n = 4). Fourteen (88%) cases received limb salvage/wide margin resection (n = 13) or intralesional surgery (n = 1). For all DCS, the median estimated overall survival (OS) was 46 months (95% CI, 1-90 months) with both a five and ten-year survival probability of 32%. On Kaplan-Meier analysis there was no difference between operative versus nonoperative management (p = 0.747), surgery alone versus surgery/chemotherapy (p = 0.265), nor surgery alone versus surgery/chemotherapy/radiation (p = 0.698). Conclusions: Our findings confirm the poor prognosis of DCS patients, though with a five-year estimate of 32%, higher than previous literature. Together with existing literature, our data may enable future strategic recommendation of DCS patients.

The prognostic significance of lymphovascular tumor invasion in localized high-grade osteosarcoma: Outcomes of a single institution over ten years

e22013

Background: Lymphovascular tumor invasion (LVI) has shown evidence of an association with worse survival in high-grade osteosarcoma. The purpose of this investigation was to prognosticate LVI as a predictor of survival in these patients. Methods: This study was a retrospective review of high-grade, localized osteosarcoma patients diagnosed over a consecutive ten-year period. Cox proportional hazards regression was used to assess the prognostic significance of LVI on overall survival (OS). Results: A total of 42 cases met inclusion criteria with a median follow-up of 64 months (range, 6-158 months). LVI was present in 21.4% (n = 9) cases. The five and ten-year probabilities of OS in LVI (+) were 40% and 20%, respectively, compared to LVI (-) with five and ten-year estimates of 93% and 81%, respectively (p < 0.001). After controlling for confounding variables, advanced age at diagnosis (HR, 1.134; 95% CI, 1-1.2; p = 0.01) and LVI (HR, 21.768; 95% CI, 3-135; p = 0.001) were found to be significantly negative predictors of OS. Using a competing risk analysis and Gray's test of equality, LVI (+) and LVI (-) were not statistically different with respect to cumulative incidence of recurrence (p = 0.8118), though were highly significant for cumulative incidence of mortality over time (p = 0.0029). Conclusions: The presence of LVI in the setting of high-grade, localized osteosarcoma is associated with greater rates of mortality and tumor recurrence and portends a dismal prognosis.

Comparison of clinicopathological features and outcomes in patients with primary leiomyosarcoma of bone and soft tissue

e23526

Background: Leiomyosarcoma is a rare malignancy that may occur in bone. This investigation described the characteristics and outcomes of primary leiomyosarcoma of bone (PLB) compared to soft tissue leiomyosarcoma (SLMS). Methods: This study was a retrospective review using the Surveillance, Epidemiology, and End Results (SEER) database from 1975 to 2016. Continuous and categorial variables were described, and Cox regression were used to identify factors of prognostic significance. Results: Seven thousand five-hundred two patients met inclusion criteria. Seventy-four (1%) were PLB and 7428 (99%) were SLMS. On multivariable analysis for high-grade SLMS radiation (neoadjuvant: HR, 0.56; 95% CI, 0.4-0.8; p = 0.003, and adjuvant: HR, 0.75; 95% CI, 0.6-0.9; p = 0.008) and surgery (procedure specific) improved DSS, while age (HR, 1.013; 95% CI, 1.0-1.1; p < 0.001), tumor size greater than or equal to 5 cm (HR, 3.16; 95% CI, 2.3-4.2; p < 0.001), abdomen/pelvis/trunk/thorax tumors (HR, 1.31; 95% CI, 1.1-1.6; p = 0.006), and distant metastases at presentation (HR, 2.6; 95% CI, 2.1-3.3; p < 0.001) negatively influenced DSS. Conclusions: Radiation and surgery positively influence survival in high-grade SLMS while chemotherapy appears to have no benefit. Surgery alone appears to lower the mortality risk in PLB.

What Is the Clinical Impact of Sending Tissue for Histopathology During Surgery for Known, Diffuse Metastatic Disease to Bone?

BACKGROUND/AIM

During surgery for patients with known, diffuse metastatic bone disease (MBD), lesional tissue is routinely sent for pathological evaluation. However, there are limited data to assess whether there is a role for histopathology for MBD despite time and cost of interpretation, as well as whether a positive sample changes the subsequent treatment course.

PATIENTS AND METHODS

Sixty-six cases from 2017 to 2020 were reviewed retrospectively. The median age at surgery was 63.5 years (range of 23 to 84 years), and the primary tumor was most frequently breast (24.2%, n=16), renal (21.2%, n=14) or lung (15.2%, n=10). The most common location of MBD was the femur (60.6%, n=40).

RESULTS

The overall yield of a positive tissue sample of MBD was 77.3% (n=51). The positive rate from sending intramedullary reamings was 65.4% (n=17 of 26). Among the 66 cases (63 patients), a change in the subsequent clinical management was recorded in 9.1% (n=6). The most common change was related to the medication regimen (n=5), with one change related to recognition of the carcinoma origin via histology, which was previously unknown.

CONCLUSION

Despite the routine practice of sending tissue for histology during surgery for known and diffuse MBD, a change in the subsequent clinical management is uncommon. Prior to sending tissue, surgeons should discuss this practice with the multidisciplinary care team on a per-patient basis.

Survival and outcomes of modular endoprosthetic reconstruction of the proximal femur for primary and non-primary bone tumors: Single institutional results

Purpose

This study assessed implant survival and dislocation following proximal femur tumor endoprosthetic replacement.

Methods

Thirty-eight procedures were performed between 2005 and 2019. The cumulative incidence of implant revision was calculated with death as a competing risk.

Results

The majority of endoprostheses were bipolar hemiarthroplasty (n = 33, 86.8%). The cumulative incidence of revision was 14.6% (95% CI, 3.2%-34.1%) at five years. Dislocation occurred in 7.9% (n = 3) of hips at a mean (SD) 44 ± 35.2 days.

Conclusions

Proximal femur tumor endoprosthetic replacement is a durable option that tends to outlive patients. Strict postoperative bracing may lower dislocation rates.

Level of evidence

III. Retrospective Study.

Epithelioid hemangioendothelioma of bone: A survival analysis of 50 cases from the SEER database (1992-2016)

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor that may arise in bone. The purpose of this investigation was to determine the clinicopathological features and outcomes of osseous EHE in a large patient series, and to assess whether survival is impacted by demographics, tumor characteristics, or treatment factors. This was a retrospective review of the Surveillance, Epidemiology and End Results (SEER) database from 1992 to 2016. Kaplan-Meier was used to estimate overall survival (OS) and disease-specific survival (DSS). A Cox regression model was used to identify prognostic factors. Fifty patients from 1992 to 2016 with a median age of 54.5 years (IQR, 37–67) were reviewed. For location, 46% (n = 23) of tumors arose from the appendicular skeleton while 38% (n = 19) occurred within the axial skeleton (overlapping EHE: 16%, n = 8). Of the cases with recorded treatment factors, 54.8% (n = 23) had surgery, 26% (n = 13) received radiation, 22% (n = 11) were treated with chemotherapy, and 26% (n = 13) had surgery plus radiation. The 5-year OS probability was 49.2% (95% CI, 23.6–70.6), and the 5-year DSS probability was 63.9% (95% CI, 33.0–83.5). No surgery (surgery: HR, 0.262; 95% CI, 0.07–0.9); p = 0.041) and age older than 50 years (HR, 4.117; 95% CI, 1.1–15.4; p = 0.035) were negative prognostic factors of disease-specific mortality after controlling for confounding variables. There was no association between disease-specific mortality and adjuvant or multimodal therapy. The prognosis of EHE of bone is less than favorable, and the 5-year DSS probability of 64% emphasizes the intermediate grade nature of this tumor subtype. Surgical treatment, when feasible, is associated with a better prognosis.

Atraumatic, Progressive, and Painful Elbow Contracture From a Ganglion Cyst

Ganglion cysts are benign soft tissue tumors that often occur adjacent to joints or tendons. We report a case of an elbow joint ganglion cyst in a patient who presented with a painful, progressive elbow contracture. The patient was successfully treated with resection of the subbrachialis ganglion cyst combined with an anterior capsular release and an ulnar nerve decompression to recover elbow motion. This case highlights the value of advanced imaging in patients presenting with an atraumatic, painful, and progressive elbow contracture.

The prognostic significance of lymphovascular tumor invasion in localized high-grade osteosarcoma: Outcomes of a single institution over 10 years

BACKGROUNDS AND OBJECTIVES

Lymphovascular invasion (LVI) has shown evidence of an association with worse survival in high-grade osteosarcoma patients. The purpose of this investigation was to prognosticate LVI as a predictor of survival.

METHODS

This was a retrospective review of high-grade, localized osteosarcoma patients over a consecutive 10-year period. Proportional hazards regression was used to identify prognostic factors. Cumulative mortality incidence was estimated with recurrence as a competing risk.

RESULTS

Forty-two cases with a median follow-up of 64 months (range, 6-158 months) were reviewed. LVI was present in 21.4% (n = 9) cases. The five- and ten-year survivals in LVI (+) were 40% and 20%, compared to 93% and 81% in LVI (-), respectively (p < .001). After controlling for confounders, advanced age (hazards ratio [HR], 1.134; 95% confidence interval [CI], 1-1.2; p = .01) and LVI (HR, 21.768; 95% CI, 3-135; p = .001) were negative prognosticators. The cumulative incidence of recurrence was no different between LVI (+) and LVI (-) (p = .811), though the incidence of mortality was significantly higher in LVI (+) (p = .003).

CONCLUSION

The presence of LVI in the setting of high-grade, localized osteosarcoma is associated with greater rates of mortality and appears to portend a dismal prognosis.

A Population-based Analysis of Lymph Node Metastasis in Extremity Soft Tissue Sarcoma: An Update

BACKGROUND

Soft tissue sarcomas (STSs) are mesenchymal tumors that may rarely metastasize to lymph nodes. This investigation sought to evaluate regional lymph node metastasis (RLNM) in extremity STS using a national cohort.

MATERIALS AND METHODS

This study was a retrospective review of the Surveillance, Epidemiology, and End Results database from 1975 to 2016. A Cox proportional hazards model was used to identify prognostic factors associated with disease-specific survival (DSS).

RESULTS

RLNM was present in 3.7% (n = 547) of extremity STS. The rate of RLNM was highest in rhabdomyosarcoma (26.7%), clear cell sarcoma (18.8%), epithelioid sarcoma (14.5%), angiosarcoma (8.1%), spindle cell sarcoma (5.0%), and synovial sarcoma (3.2%). The 5-year DSS probability without RLNM was 69% (standard error: 1.3%) compared to 26% (standard error: 3.6%) with RLNM (P < 0.001). For the historically high-risk extremity STS, advanced age (hazard ratio (HR), 1.036; 95% confidence interval (CI), 1.0-1.04; P < 0.001), higher grade tumors (HR, 1.979; 95% CI, 1.3-3.0; P < 0.001), tumor size greater than 10 cm (HR, 1.892; 95% CI, 1.3-2.7; P < 0.001), primary site surgery (HR, 0.529; 95% CI, 0.3-0.8; P = 0.006), distant metastasis (HR, 4.585; 95% CI, 3.0-6.8; P < 0.001), and RLNM (HR, 2.153; 95% CI, 1.3-3.5; P = 0.003) were each independent disease-specific prognostic factors.

CONCLUSIONS

The prognosis of RLNM in historically high-risk extremity STS is poor with a 5-year DSS of 26%. These data support a staging system of STS inclusive of nodal involvement and contribute to the growing body of evidence that characterizes the rates of RLNM in STS.

Comparison of clinicopathological features and outcomes in patients with primary leiomyosarcoma of bone and soft tissue

BACKGROUNDS AND OBJECTIVES

This investigation sought to describe the outcomes of primary leiomyosarcoma of bone (PLB) compared to soft tissue leiomyosarcoma (SLMS).

METHODS

This was a review of the Surveillance, Epidemiology, and End Results database from 1975 to 2016. Kaplan-Meier methods were used to estimate disease-specific survival (DSS), and a Cox regression model was used to identify prognostic factors.

RESULTS

Of the 7502 identifiable cases, 1% (n = 74) were PLB and 99% (n = 7428) were SLMS. Survival was the same between PLB and SLMS (p = .209). On multivariable analysis for high-grade SLMS, radiation (neoadjuvant: hazard ratio [HR], 0.56; 95% confidence interval [CI], 0.4-0.8; p = .003; adjuvant: HR, 0.75; 95% CI, 0.6-0.9; p = .008) and surgery (procedure specific) improved DSS. For PLB, wide resection/limb salvage (HR, 0.40; 95% CI, 0.3-0.5; p = .018) and amputation (HR, 0.69; 95% CI, 0.5-0.9; p < .001) were positive prognostic factors. Neither radiation nor chemotherapy were prognostic factors for survival in PLB.

CONCLUSIONS

For SLMS, radiation portends a survival advantage. For PLB, however, neither chemotherapy nor radiation were significant prognostic factors, which suggests the optimal treatment for PLB, similar to other primary soft tissue sarcomas originating in bone, remains an unmet medical need.