Superoxide Dismutase Mimetic Avasopasem Manganese Enhances Radiation Therapy Effectiveness in Soft Tissue Sarcomas and Accelerates Wound Healing

Soft tissue sarcomas (STSs) are mesenchymal malignant lesions that develop in soft tissues. Despite current treatments, including radiation therapy (RT) and surgery, STSs can be associated with poor patient outcomes and metastatic recurrences. Neoadjuvant radiation therapy (nRT), while effective, is often accompanied by severe postoperative wound healing complications due to damage to the surrounding normal tissues. Thus, there is a need to develop therapeutic approaches to reduce nRT toxicities. Avasopasem manganese (AVA) is a selective superoxide dismutase mimetic that protects against IR-induced oral mucositis and lung fibrosis. We tested the efficacy of AVA in enhancing RT in STSs and in promoting wound healing. Using colony formation assays and alkaline comet assays, we report that AVA selectively enhanced the STS (liposarcoma, fibrosarcoma, leiomyosarcoma, and MPNST) cellular response to radiation compared to normal dermal fibroblasts (NDFs). AVA is believed to selectively enhance radiation therapy by targeting differential hydrogen peroxide clearance in tumor cells compared to non-malignant cells. STS cells demonstrated increased catalase protein levels and activity compared to normal fibroblasts. Additionally, NDFs showed significantly higher levels of GPx1 activity compared to STSs. The depletion of glutathione using buthionine sulfoximine (BSO) sensitized the NDF cells to AVA, suggesting that GPx1 may, in part, facilitate the selective toxicity of AVA. Finally, AVA significantly accelerated wound closure in a murine model of wound healing post RT. Our data suggest that AVA may be a promising combination strategy for nRT therapy in STSs.

A Pilot Study of Nutritional Supplementation in Soft Tissue Sarcoma Patients

Background

Wound healing is particularly important for sarcoma patients who undergo neoadjuvant radiation therapy. Previous studies have demonstrated wound complications in this population approaching 35%. With this high rate of wound healing issues, identifying treatment modalities to minimize these complications is of paramount importance.

Methods

All patients with high grade bone and soft tissue sarcoma received 15 days of twice daily amino acid supplementation starting in the immediate post-operative period. We documented the healing status of the surgical wound, the primary outcome, at all follow up appointments until six months after surgery. Non-healing wounds were defined as any wound requiring 1) a return visit to the OR for debridement, 2) IV antibiotics (ABX), and 3) unhealed wounds at 6 months post-operatively.1 For each patient, we collected biometrics with lean body mass analysis at preoperative appointment, and two and six weeks postoperatively. The proportion with non-healing wounds was compared with a historical patient cohort using the chi-square test. In a subgroup of participants with body composition measurements, we also compared changes in mean fat mass, lean mass, and psoas index from pre-operative baseline to 6 months post-operative using generalized linear models.

Results

A total of 33 consecutive patients were supplemented with a branched chain amino acid (BCAA) formulation. The historical cohort included 146 participants from the previous 7 years (2010-2017). 26% of patients in the historical cohort experienced wound complications compared to 30% in the supplemented group. (p=0.72) When focusing specifically on lower extremity sarcomas treated with neoadjuvant radiation therapy, 46% of patients in the supplemented group experienced wound healing complications compared to 39% in the non-supplemented group (p=0.68). BCAA supplementation was found to be protective with regards to decreasing muscle wasting with no difference in psoas index measurements throughout the study period compared to a 20% muscle loss in the historical cohort (p=0.02).

Conclusion

In our limited sample size, there was no difference in wound healing complications between sarcoma patients who received postoperative BCAA supplementation compared to a historical cohort who were not supplemented. Patients who did not receive supplementation had a significant decline in post-operative psoas index following operative sarcoma removal. Level of Evidence: III.

Mechanical Gains Associated With Virtual Prophylactic Intramedullary Nail Fixation in Femurs With Metastatic Disease

Background

Many patients with metastatic bone disease (MBD) of the femur undergo prophylactic surgical fixation for impending pathologic fractures; intramedullary nailing (IMN) being the most common fixation type. However, surgeons often question if IMN fixation provides sufficient improvements in mechanical strength for particular metastatic lesions. Our goal was to use patient-specific finite element (FE) modeling to computationally evaluate the effects of simulated IMN fixation on the mechanics of femurs affected with MBD.

Methods

Computed tomography (CT) scans were available retrospectively from 48 patients (54 femurs) with proximal femoral metastases. The CT scans were used to create patient-specific, non-linear, voxel-based FE models of the femur, simulating the instant of peak hip joint contact force during normal walking. FE analyses were repeated after incorporating virtual IMN fixation (Smith and Nephew, TRIGEN INTERTAN) into the same femurs. Femur strength and load-to-strength ratio (LSR; lower LSR indicates lower fracture risk) were compared between untreated and IMN conditions using statistical analyses.

Results

IMN fixation resulted in a very modest average 10% increase in mechanical strength (p<0.001), which was associated with a slight 7% reduction in fracture risk (p<0.001). However, there was considerable variation in fracture risk reduction between individual femurs (0.13-50%). In femurs with the largest reduction in fracture risk (>10%), IMN hardware directly passed through a considerable section of that femur's metastatic lesion. Femurs with lytic (10%) and diffuse (9%) metastases tended to have greater reductions in fracture risk compared to femurs with blastic (5%) and mixed (4%) metastases (p=0.073).

Conclusion

Given the mechanically strong baseline condition of most femurs in this cohort, evident by the low fracture risk at the time of CT scanning, the relative increase in stiffness with the addition of the IMN hardware may not make a substantial contribution to overall mechanical strength. The mechanical gains of IMN fixation in femurs with MBD appear most beneficial when the hardware traverses an adequate section of the lesion. Level of Evidence: III.

T2* Imaging Assessment of Neoadjuvant Radiation Therapy Combined With Pharmacological Ascorbate in Extremity Soft-Tissue Sarcomas: A Pilot Study

Background

Extremity soft-tissue sarcomas (STS) are commonly treated with neoadjuvant radiation therapy followed by surgical resection. However, the pathological near-complete response rate is low (9-25%). Noninvasive imaging assessment that predicts treatment response before and during treatment is desirable to optimize treatment regimens. This pilot study aimed to investigate the application of a quantitative MRI parameter, T2*, in assessing neoadjuvant radiation therapy combined with pharmacological ascorbate in extremity STS.

Methods

This prospective cohort study included seven patients diagnosed with extremity STS and scheduled to receive neoadjuvant radiation therapy combined with pharmacological ascorbate. T2* maps were obtained from each patient before treatment (baseline MRI), two weeks after initiating treatment (on-treatment MRI), and before surgery (pre-surgery MRI). The T2* values within the tumor region were transformed into z-scores with respect to the normal- appearing tissue region. The voxel-wise z-scores within the tumor region were thresholded to generate masks representing significantly high (z-score>1.96) and low z-score (z-score<-1.96) voxels. The means of the total z-scores and within each of the significantly high and low z-score mask were computed. Their correlations with percent necrosis from pathological examination were evaluated using Spearman's rank correlation coefficient r. A correlation was considered as moderate or strong when r is higher than 0.6 and 0.8, respectively. A correlation was considered as fair or weak when r is below 0.6.

Results

For the baseline and on-treatment MRIs, the means of the significantly high z-scores of the T2* measurements showed moderate correlations with percent necrosis (r = 0.68 and 0.6; p = 0.11 and 0.24). For the pre-surgery MRI, the means of the total and significantly high z-scores showed strong correlations with percent necrosis (r = 0.8 and 0.9; p = 0.13 and 0.08). Tumor volume and baseline MRI-based percent necrosis showed fair or weak correlations (r = 0.3-0.54; p = 0.24-0.68).

Conclusion

T2* measurements prior to treatment, two weeks after initiating treatment, and before surgery showed moderate to strong correlations with percent necrosis. These results support the potential for using T2* mapping to predict and assess response to neoadjuvant radiation therapy combined with pharmacological ascorbate in extremity STS. Level of Evidence: IV.

Transcutaneous Oximetry Does Not Reliably Predict Wound-healing Complications in Preoperatively Radiated Soft Tissue Sarcoma

BACKGROUND

Surgical wound-healing complications after tumor resections in tissue that has been preoperatively radiated are a major clinical problem. Most studies have reported that complications occur in more than 30% of patients undergoing such resections in the lower extremity. There is currently no available method to predict which patients are likely to have a complication. Transcutaneous oximetry has been identified in preliminary studies as potentially useful, but the available evidence on its efficacy for this application thus far is inconclusive.

QUESTIONS/PURPOSES

(1) Does transcutaneous oximetry measurement below 25 mmHg at any location in the surgical wound bed predict a wound-healing complication? (2) Does recovery (increase) in transcutaneous oxygen measurement during the rest period between the end of radiation and the time of surgery protect against wound-healing complications?

METHODS

A prospective, multi-institution study was coordinated to measure skin oxygenation at three timepoints in patients undergoing surgery for a lower extremity soft tissue sarcoma after preoperative radiation. Between 2016 and 2020, the five participating centers treated 476 patients for lower extremity soft tissue sarcoma. Of those, we considered those with a first-time sarcoma treated with radiation before limb salvage surgery as potentially eligible. Based on that, 21% (98 of 476) were eligible; a further 12% (56 of 476) were excluded because they refused to participate or ultimately, they were treated with a flap, amputation, or skin graft. Another 1% (3 of 476) of patients were lost because of incomplete datasets or follow-up less than 6 months, leaving 8% (39 of 476) for analysis here. The mean patient age was 62 ± 14 years, 62% (24 of 39) of the group were men, and 18% (7 of 39) of patients smoked cigarettes; 87% (34 of 39) of tumors were intermediate/high grade, and the most common histologic subtype was undifferentiated pleomorphic sarcoma. In investigating complications, a cutoff of 25 mmHg was chosen based on a pilot investigation that identified this value. All patients were assessed for surgical wound-healing complications, which were defined as: those resulting in a return to the operating room, initiation of oral or IV antibiotics, intervention for seroma, or prolonged wound packing or dressing changes. To answer the first research question, we compared the proportion of patients who developed a wound-healing complication between those patients who had any reading below 25 mmHg (7 of 39) and those who did not (32 of 39). To answer the second question, we compared the group with stable or decreased skin oxygenation (22 of 37 patient measurements [two patients missed the immediate postoperative measurement]) to the group that had increased skin oxygen measurement (15 of 37 measurements) during the period between the end of radiation and the surgical procedure; again, the endpoint was the development of a wound-healing complication. This study was powered a priori to detect an unadjusted odds ratio for wound-healing complications as small as 0.71 for a five-unit (5 mmHg) increase in TcO 2 between the groups, with α set to 0.05, β set to 0.2, and a sample size of 40 patients.

RESULTS

We found no difference in the odds of a wound-healing complication between patients whose transcutaneous oxygen measurements were greater than or equal to 25 mmHg at all timepoints compared with those who had one or more readings below that threshold (odds ratio 0.27 [95% confidence interval (CI) 0.05 to 1.63]; p = 0.15). There was no difference in the odds of a wound-healing complication between patients who had recovery of skin oxygenation between radiation and surgery and those who did not (OR 0.63 [95% CI 0.37 to 5.12]; p = 0.64).

CONCLUSION

Transcutaneous oximetry cannot be considered a reliable test in isolation to predict wound-healing complications. This may be a function of the fact that transcutaneous oximetry samples a relatively small portion of the landscape in which a wound-healing complication could potentially arise. In the absence of a reliable diagnostic test, clinicians must still use their best judgment regarding surgical timing and work to address modifiable risk factors to avoid complications. The unanswered question that remains is whether there is a skin perfusion or oxygenation issue at the root of these complications, which seems likely. Alternative approaches that can assess the wound more broadly and in real time, such as fluorescent probes, may be deserving of further investigation.

LEVEL OF EVIDENCE

Level II, diagnostic study.

Adjuvant treatment of surgically treated bone metastasis patients: association with hospital characteristics and trends over time

Patients with metastatic disease of the bone (MDB) often require surgical stabilization; however, there is not widespread consensus on subsequent adjuvant management. This study aimed to characterize utilization of perioperative adjuvant treatment among MDB patients. We identified 9413 surgically treated MDB patients with primary (breast, kidney, lung, prostate, or multiple myeloma) cancer from Surveillance, Epidemiology, and End Results (SEER)-Medicare data. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for receipt of chemotherapy, radiation, and bisphosphonates, respectively, in the adjuvant setting (90 days before or after surgery) by hospital characteristics-medical school affiliation, surgery volume, and Commission on Cancer (CoC) accreditation. Trends in treatment utilization by year of surgery were assessed via bar charts and Chi-square tests for trend. Patients surgically treated at major medical schools or high-volume facilities (compared to no medical school affiliation and low volume) had significantly higher odds of receiving radiation and chemotherapy, independent of patient and tumor characteristics (OR (95% CI); medical school: radiation 1.33 (1.19-1.49), chemotherapy 1.15 (1.02-1.30); and high volume: radiation 1.22 (1.11-1.34), chemotherapy 1.11 (1.02-1.22)). Patients surgically treated at CoC-accredited institutions, compared to non-accredited, had significantly higher odds of receiving radiation and bisphosphonates [radiation 1.24 (1.13-1.36); bisphosphonates 1.15 (1.04-1.28)]. Use of chemotherapy and bisphosphonates increased while radiation use declined over the study period from 1991 to 2014. Medical school affiliation, hospital volume, and CoC accreditation are associated with receipt of adjuvant treatment to prevent or manage pathologic fractures in MDB patients. Further investigation is needed to determine whether these associations reflect delivery of optimal care.

Characteristics and Long-Term Outcome of Surgically Managed High-Grade Extremity Chondrosarcoma

Background

Dedifferentiated chondrosarcoma (DCS) is a highly malignant variant that portends a poor prognosis. Although factors such as clinico-pathological characteristics, surgical margin, and adjuvant modalities likely play a role in overall survival, debate continues with varying results on the importance of these indicators. The purpose of this study is (1) To delineate the characteristics, local recurrence (LR), and survival of patients with intermediate (IGCS), high (HGCS) and dedifferentiated (DCS) chondrosarcoma of the extremity by utilizing detailed cases at one tertiary institution. (2) To assess survival between high grade chondrosarcoma and DCS utilizing a less detailed but large cohort from the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

Twenty-six cases of high-grade (conventional FNCLCC grades 2 and 3, dedifferentiated) chondrosarcoma were identified from an ongoing prospective cohort of 630 sarcoma patients managed surgically at a tertiary referral university hospital between 9/1/2010-12/30/2019. A retrospective review of demographics, tumor characteristics, surgical procedure, treatment course, and survival data was performed to determine prognostic factors for survival. An additional 516 cases of chondrosarcoma were identified from the SEER database. Using the Kaplan-Meier method, both the large database and case series were evaluated, and estimated cause-specific survival was calculated at 1, 2, and 5 years.

Results

There were 12 IGCS, 5 HGCS, and 9 DCS patients in the single institution cohort. DCS had a higher stage at diagnosis (p=0.04). Limb salvage was the most common procedure performed in every group (11/12 IGCS, 5/5 HGCS, and 7/9 DCS; p=0.56). Margins included 8/12 wide and 3/12 intralesional for IGCS. For HGCS, there were 3/5 wide, 1/5 marginal, and 1/5 intralesional. A majority of DCS margins were wide (8/9) with only 1 marginal. There was no difference of associated margins between the groups (p=0.85), however there was a difference when margins were classified based on numerical measurement (IGCS: 0.125cm (0.1-0.35); HGCS: 0cm (0-0.1); DCS: 0.2cm (0.1-0.5); p=0.03). The overall median follow-up was 26 months (IQR:16.1-70.8). The time interval from resection to death was lower in DCS (11.5 months (10.7-12.2)), followed by IGCS (30.3 months (16.2-78.2)), and HGCS (55.1 months (32.0-78.2; p=0.047). LR occurred in 5/9 DCS, 1/5 HGCS, and 1/14 IGCS patients. Of the DCS patients only 2/6 who received systemic therapy had LR, while all 3/3 who did not receive systemic therapy had LR. Overall systemic therapy and radiation did not impact incidence of LR (p=0.67; p=0.34). However, patients who had LR were 17.5 times more likely to die within one year (HR=17.5, 95%CI (1.01-303.7), p=0.049), after adjusting for the age at the surgery. There was no correlation with the utilization of systemic therapy, radiation therapy, or margin and overall survival (p=0.63, p=0.52, p=0.74). In the SEER patient cohort, 149 cases (28.9%) were DCS and 367 (71.1%) were HGCS. At final follow-up, 49.6% (n=256) of the cohort had a cause of death due to chondrosarcoma. HGCS was associated with higher chance of 1-year survial (p<0.001), 2-year survival (p<0.001), 5-year survival (p<0.001), and overall survival (p<0.001). Additionally, decreased survival was associated with metastatic disease at presentation (p=0.01). Overall limb salvage was most utilized for both HGCS (76.5%) and DCS (74.3%). In regard to limb salvage vs. amputation, there was no difference in survival at 1 year (p=0.10) or 2 year (p=0.13) between the groups, however those who underwent limb salvage procedure had a significantly better chance of survival at 5 years when compared to amputation (HR=1.49 (1.11-1.99); p=0.002).

Conclusion

High-grade chondrosarcoma remains a fatal disease in many patients, particularly if associated with dedifferentiated subtype. Interestingly, all (100%) DCS patients who did not receive systemic therapy had LR. However, chemotherapy and radiation did not significantly increase survival. In this case series and large database study, HGCS had the smallest surgical margin, but with the longest time interval for both LR and death. Additionally, using the SEER database, DCS and amputation had worse prognosis at the 5-year survival time. Further studies on valuable prognostic influences as well as earlier identification of this rare disease may help in developing better management options. Level of Evidence: III.

Effects of Radiotherapy Upon Bone Structure-Strength Relationships Vary With Sex and Fractionation of Dosing

Background

Radiotherapy for tumor treatment in or near bones often causes osteopenia and/or osteoporosis, and the resulting increased bone fragility can lead to pathologic fractures. Bone mineral density (BMD) is often used to screen for fracture risk, but no conclusive relationship has been established between BMD and the microstructural/ biomechanical changes in irradiated bone. Understanding the effects of radiation dosing regimen on the bone structure-strength relationship would improve the ability to reduce fracture-related complications resulting from cancer treatment.

Methods

Thirty-two C57B6J mice aged 10 - 12 weeks old were randomized to single dose (1 x 25 Gy) and fractionated dose (5 x 5 Gy) irradiation groups. Right hindlimbs were irradiated while the contralateral hindlimbs served as the non-irradiated control. Twelve weeks after irradiation, BMD and bone microstructure were assessed with micro-computed tomography, and mechanical strength/stiffness was assessed with a torsion test. The effects of radiation dosing regimen on bone microstructure and strength were assessed using ANOVA, and bone strength-structure relationships were investigated through correlation analysis of microstructural and mechanical parameters.

Results

Fractionated irradiation induced significantly greater losses in BMD in the femur (23% - male mice, p=0.016; 19% - female mice) and the tibia (18% - male mice; 6% - female mice) than the single-dose radiation. The associated reductions in trabecular bone volume (-38%) and trabecular number (-34% to -42%), and the increase in trabecular separation (23% to 29%) were only significant in the male mice with fractionated dosing. There was a significant reduction in fracture torque in the femurs of male (p=0.021) and female (p=0.0017) mice within the fractionated radiation group, but not in the single dose radiation groups. There was moderate correlation between bone microstructure and mechanical strength in the single-dose radiation group (r = 0.54 to 0.73), but no correlation in the fractionated dosing group (r=0.02 to 0.03).

Conclusion

Our data indicate more detrimental changes in bone microstructure and mechanical parameters in the fractionated irradiation group compared to the single dose group. This may suggest the potential for protecting bone if a needed therapeutic radiation dose can be delivered in a single session rather than administered in fractions.

Finite Element Model-Computed Mechanical Behavior of Femurs with Metastatic Disease Varies Between Physiologic and Idealized Loading Simulations

Background and objectives:

Femurs affected by metastatic bone disease (MBD) frequently undergo surgery to prevent impending pathologic fractures due to clinician-perceived increases in fracture risk. Finite element (FE) models can provide more objective assessments of fracture risk. However, FE models of femurs with MBD have implemented strain- and strength-based estimates of fracture risk under a wide variety of loading configurations, and “physiologic” loading models typically simulate a single abductor force. Due to these variations, it is currently difficult to interpret mechanical fracture risk results across studies of femoral MBD. Our aims were to evaluate (1) differences in mechanical behavior between idealized loading configurations and those incorporating physiologic muscle forces, and (2) differences in the rankings of mechanical behavior between different loading configurations, in FE simulations to predict fracture risk in femurs with MBD.

Methods:

We evaluated 9 different patient-specific FE loading simulations for a cohort of 54 MBD femurs: strain outcome simulations—physiologic (normal walking [NW], stair ascent [SA], stumbling), and joint contact only (NW contact force, excluding muscle forces); strength outcome simulations—physiologic (NW, SA), joint contact only, offset torsion, and sideways fall. Tensile principal strain and femur strength were compared between simulations using statistical analyses.

Results:

Tensile principal strain was 26% higher ( R2 = 0.719, P < .001) and femur strength was 4% lower ( R2 = 0.984, P < .001) in simulations excluding physiologic muscle forces. Rankings of the mechanical predictions were correlated between the strain outcome simulations (ρ = 0.723 to 0.990, P < .001), and between strength outcome simulations (ρ = 0.524 to 0.984, P < .001).

Conclusions:

Overall, simulations incorporating physiologic muscle forces affected local strain outcomes more than global strength outcomes. Absolute values of strain and strength computed using idealized (no muscle forces) and physiologic loading configurations should be used within the appropriate context when interpreting fracture risk in femurs with MBD.

Finite element analysis potentially identifies nonessential prophylactic stabilization in femurs with metastatic disease

Metastatic bone disease (MBD) is often managed by non-specialized orthopedic surgeons who rely on Mirels’ criteria to predict pathologic fracture risk. However, low specificity of Mirels’ criteria implies many lesions are scored at high fracture risk when the actual mechanical fracture risk is minimal. Our goal was to retrospectively compare mechanical fracture risk in MBD patients to Mirels’ score and clinical treatment received. Using a CT-based finite element (FE) model of the proximal femur affected by MBD, femur strength and load-to-strength ratio (LSR) were determined for 52 femurs from 48 patients. Associations of femur strength with pain and Mirels’ scores (Pearson r/Spearman ρ correlations), and the decision to operate (percentile analysis), and associations of LSR with pain and Mirels’ scores (Spearman correlations) were determined. Nineteen of 52 femurs (37%) had a very low computed mechanical fracture risk (LSR < 0.4); 5 of those 19 underwent prophylactic stabilization, suggesting that clinical decision-making in MBD is substantially influenced by non-mechanical factors that likely overestimate pathologic fracture risk. Of the 30 femurs managed non-operatively, 24 had a low computed mechanical fracture risk (LSR ≤ 0.5), none of which (0%) experienced a fracture within 9 months. Patient-reported pain did not correlate with femur strength ( r = −0.05, p = 0.748) nor with LSR (ρ = 0.07, p = 0.632). Mirels’ score correlated weakly with femur strength (ρ = −0.32, p = 0.019) and with LSR (ρ = 0.29, p = 0.034). Computational mechanical tools like this FE model could be used as a clinical decision aid when considering non-surgical management in appropriate patients, potentially alleviating nonessential surgical treatment in some patients with femur MBD.

The Influence of Hospital Characteristics on Patient Survival in Surgically Managed Metastatic Disease of Bone: An Analysis of the SEER-Medicare Linked Database

OBJECTIVES

We investigated whether patients receiving surgical treatment for metastatic disease of bone (MDB) at hospitals with higher volume, medical school affiliation, or Commission on Cancer accreditation have superior outcomes.

MATERIALS AND METHODS

Using the Surveillance, Epidemiology, and End Results-Medicare database, we identified 9413 patients surgically treated for extremity MDB between 1992 and 2014 at the age of 66 years or older. Cox proportional hazards models were used to calculate the hazards ratios (HR) for 90-day and 1-year mortality and 30-day readmission according to the characteristics of the hospital where bone surgery was performed.

RESULTS

We observed no notable differences in 90-day mortality, 1-year mortality, or 30-day readmission associated with hospital volume. Major medical school affiliation was associated with lower 90-day (HR: 0.88, 95% confidence interval [CI]: 0.80-0.96) and 1-year (HR: 0.92, 95% CI: 0.87-0.99) mortality after adjustments for demographic and tumor characteristics. Surgical treatment at Commission on Cancer accredited hospitals was associated with significantly higher risk of death at 90 days and 1 year after the surgery. This effect appeared to be driven by lung cancer patients (1-year HR: 1.17, 95% CI: 1.07-1.27).

CONCLUSIONS

Our findings suggest surgical management of MDB at lower-volume hospitals does not compromise survival or readmissions. There may be benefit to referral or consultation with an academic medical center in some tumor types or clinical scenarios.

The Relationship Between Lesion Size and Load to Failure After Stabilization of Simulated Metastatic Lesions of the Proximal Femur

BACKGROUND

As overall cancer survival continues to improve, the incidence of metastatic lesions to the bone continues to increase. The subsequent skeletal related events that can occur with osseous metastasis can be debilitating. Complete and impending pathologic femur fractures are common with patients often requiring operative fixation. However, the efficacy of an intramedullary nail construct, on providing stability, continue to be debated. Therefore, the purpose of this study was to utilize a synthetic femur model to determine 1) how proximal femur defect size and cortical breach impact femur load to failure (strength) and stiffness, and 2) and how the utilization of an IMN, in a prophylactic fashion, subsequently alters the overall strength and stiffness of the proximal femur.

METHODS

A total of 21 synthetic femur models were divided into four groups: 1) intact (no defect), 2) 2 cm defect, 3) 2.5 cm defect, and 4) 4 cm defect. An IMN was inserted in half of the femur specimens that had a defect present. This procedure was performed using standard antegrade technique. Specimens were mechanically tested in offset torsion. Force-displacement curves were utilized to determine each constructs load to failure and overall torsional stiffness. The ultimate load to failure and construct stiffness of the synthetic femurs with defects were compared to the intact synthetic femur, while the femurs with the placement of the IMN were directly compared to the synthetic femurs with matching defect size.

RESULTS

The size of the defect invertedly correlated with the load the failure and overall stiffness. There was no difference in load to failure or overall stiffness when comparing intact models with no defect and the 2 cm defect group (p=0.98, p=0.43). The 2.5 cm, and 4.5 cm defect groups demonstrated significant difference in both load to failure and overall stiffness when compared to intact models with results demonstrating 1313 N (95% CI: 874-1752 N; p<0.001) and 104 N/mm (95% CI: 98-110 N/mm; p=0.03) in the 2.5 cm defect models, and 512 N (95% CI: 390-634 N, p<0.001) and 21 N/mm (95% CI: 9-33 N/mm, p<0.001) in the models with a 4 cm defect. Compared to the groups with defects, the placement an IMN increased overall stiffness in the 2.5 cm defect group (125 N/mm; 95% CI:114-136 N/mm; p=0.003), but not load to failure (p=0.91). In the 4 cm defect group, there was a significant increase in load to failure (1067 N; 95% CI: 835-1300 N; p=0.002) and overall stiffness (57 N/mm; 95% CI:46-69 N/mm; p=0.001).

CONCLUSION

Prophylactic IMN fixation significantly improved failure load and overall stiffness in the group with the largest cortical defects, but still demonstrated a failure loads less than 50% of the intact model. This investigation suggests that a cortical breach causes a loss of strength that is not completely restored by intramedullary fixation. Level of Evidence: II.

Detection of Ferritin Expression in Soft Tissue Sarcomas With MRI: Potential Implications for Iron Metabolic Therapy

BACKGROUND

Cancer cells often have altered iron metabolism relative to non-malignant cells with increased transferrin receptor and ferritin expression. Targeting iron regulatory proteins as part of a cancer therapy regimen is currently being investigated in various malignancies. Anti-cancer therapies that exploit the differences in iron metabolism between malignant and non-malignant cells (e.g. pharmacological ascorbate and iron chelation therapy) have shown promise in various cancers, including glioblastoma, lung, and pancreas cancers. Non-invasive techniques that probe tissue iron metabolism may provide valuable information for the personalization of iron-based cancer therapies. T₂* mapping is a clinically available MRI technique that assesses tissue iron content in the heart and liver. We aimed to investigate the capacity of T₂* mapping to detect iron stores in soft tissue sarcomas (STS).

METHODS

In this study, we evaluated T₂* relaxation times ex vivo in five STS samples from subjects enrolled on a phase Ib/IIa clinical trial combining pharmacological ascorbate with neoadjuvant radiation therapy. Iron protein expression levels (ferritin, transferrin receptor, iron response protein 2) were evaluated by Western blot analysis. Bioinformatic data relating clinical outcomes in STS patients and iron protein expression levels were evaluated using the KMplotter database.

RESULTS

There was a high level of inter-subject variability in the expression of iron protein and T₂* relaxation times. We identified that T₂* relaxation time is capable of accurately detecting ferritin-heavy chain expression (r = -0.96) in these samples. Bioinformatic data acquired from the KMplot database revealed that transferrin receptor and iron-responsive protein 2 may be negative prognostic markers while ferritin expression may be a positive prognostic marker in the management of STS.

CONCLUSION

These data suggest that targeting iron regulatory proteins may provide a therapeutic approach to enhance STS management. Additionally, T₂* mapping has the potential to be used a clinically accessible, non-invasive marker of STS iron regulatory protein expression and influence cancer therapy decisions that warrants further investigation. Level of Evidence: IV.

Local Recurrence of Soft Tissue Sarcoma Revisited: Is there a Role for "Selective" Radiation?

BACKGROUND

Radiation therapy (RT) is often utilized in cases of high-grade soft tissue sarcoma (STS), but there remain situations where treatment is with surgical excision alone. Our goals were to determine (1) the local recurrence (LR) rate with and without perioperative RT and (2) associations between local recurrence, patient, tumor, and treatment variables.

METHODS

We performed a retrospective review of 165 consecutive STS patients. A Cox proportional hazards model was used to investigate variables associated with local recurrence.

RESULTS

LR occurred in 15/78 (19%) without RT, 4/29 (14%) with postoperative RT, and 0/58 with preoperative RT (p=0.002). We found increased rates of local recurrence at 24 months for myxofibrosarcoma (p=0.001) and no-RT (p=0.003). Myxofibrosarcoma accounted for 33 (20%) of the study patients and 12 (63%) of the local recurrences.

CONCLUSION

The LR rate in patients treated with surgery alone was disproportionately attributable to myxofibrosarcoma (11/23 cases, 48%). Other subtypes demonstrated a lower rate of LR in the absence of RT (4/55 cases, 7%), and no LR occurred when final margins were >2 mm. In certain circumstances treatment with a negative margin surgical resection followed by close observation is justifiable. RT is effective and should continue to be considered routinely in myxofibrosarcoma or when surgical margins are inadequate. Level of Evidence: III.

Prepare for Health Care 2030

By 2030, nobody will accept poor results in health care. In most cases of chronic illness, people will benefit from becoming active partners in their own health care journey. Medical professionals will focus on communication skills to become trusted navigators rather than impersonal technicians. Patient advocates and multidisciplinary teams will be key sources of support in a borderless healthcare system. Patients and paymasters will drive these innovations. Doctors will recognise them as an opportunity to avoid burnout. There is room for optimism. The healthcare system has the potential to deliver better outcomes at a lower cost.

Novel Scoring Criteria for Preoperative Prediction of Neoadjuvant Chemotherapy Response in Osteosarcoma

BACKGROUND

The extent of tumor necrosis after neoadjuvant chemotherapy is an important predictive factor of survival in osteosarcoma. However, the response to chemotherapy is not known until after the definitive resection and limits the utility of this information for operative planning. Our study questions include: 1) Are there clinical and radiographic factors following neoadjuvant chemotherapy, but prior to the tumor resection, that may aid in predicting response to treatment? 2) Can we combine these criteria into a predictive composite score that can identify good and poor responders to chemotherapy?

METHODS

We identified consecutive patients diagnosed with osteosarcoma and managed with neoadjuvant chemotherapy prior to surgical resection. We assessed post-chemotherapy tumor ossification, tumor size and growth, and the presence of pain to devise a scoring criteria to predict the percent necrosis on the final histologic specimen. Bivariate analyses were done, and a receiver operating characteristic curve was constructed to determine predictive capacity.

RESULTS

Out of the 40 patients included in this study, 15 (38%) had a good response (≥ 90% necrosis) to treatment and ten patients (25%) had a poor response with ≤ 50% necrosis. Tumor size, growth and increase in ossification were significantly associated with a good response to treatment. For good responders, a composite score of 6 was seen to attain the highest sensitivity and specificity, 100% and 84%, respectively. Tumor size, no change in ossification, and post-chemotherapy pain were significantly associated with a poor response to treatment. For poor responders, a composite score of 7 was seen to have the highest sensitivity and specificity, 100% and 63%, respectively.

CONCLUSION

Compared to the use of one single factor, our combined scoring criteria demonstrated a far improved accuracy in identifying good responders to neoadjuvant chemotherapy, where a score of 6 or less is predictive of a good response. However, the specificity of this scoring criteria to predict poor responders was low, indicating that this criterion may not be the most accurate method to identify poor responders. The utility of this score has implications regarding pre-operative counseling of the patient and operative planning.Level of Evidence: III.

Accuracy of X-Ray and Magnetic Resonance Imaging in Defining the Tumor Margin in Primary Bone Sarcoma

BACKGROUND

Limb-salvage surgery for primary bone sarcomas are preceded by X-ray and MRI for surgical planning. However, the accuracy of X-ray and MRI predicted margins are not well described. Our study examined these questions: (1) How accurately do X-ray and MRI margin measurements reflect the true margin on pathology reports? (2) Do X-ray or MRI margin measurements have smaller differences compared to pathology reports? (3) How many X-ray or MRI margin measurement differences were greater than 1 cm, 2 cm, and 3 cm from pathology reports? (4) Is there an X-ray or MRI view that consistently results in a smaller difference from pathology reports?

METHODS

This retrospective chart review examined patients with primary bone sarcoma treated with limb-salvage surgery. Reviewers used electronic measurement tools to determine margins from X-ray or MRI based on the resection length of the pathologic specimen. Mean differences of margin measurements to pathology reports were calculated. We determined outliers of imaging margin measurements at 1 cm, 2 cm, and 3 cm differences to pathology reports.

RESULTS

In the total cohort of 39 patients, the mean difference of X-ray and MRI margins compared to pathology reports were 1.09 cm (st dev 0.79 cm) and 0.71 cm (st dev 0.70 cm), respectively. MRI margin measurements had smaller differences compared to pathology reports than X-ray in 32 of 38 cases (84%) with complete imaging. X-ray outliers at 1 cm, 2 cm, and 3 cm differences were 36, 14 and 2 respectively for 70 margin measurements and MRI outliers at 1 cm, 2 cm, and 3 cm differences were 17, 6, and 0 respectively for 66 margin measurements. The views with the smallest difference were anterior-posterior X-rays and MRI views with the closest predicted margin.

CONCLUSION

Electronic MRI margin measurements with the closest predicted margin provided the smallest differences with pathology reports and are therefore the most accurate for preoperative planning. When there is adequate residual diaphysis for reconstructive fixation, surgeons should plan for a 3 cm bone margin using MRI measurements to ensure complete removal of the intramedullary extent of sarcoma.Level of Evidence: IV.

The preoperative machine learning algorithm for extremity metastatic disease can predict 90-day and 1-year survival: An external validation study

BACKGROUND

The prediction of survival is valuable to optimize treatment of metastatic long-bone disease. The Skeletal Oncology Research Group (SORG) machine-learning (ML) algorithm has been previously developed and internally validated. The purpose of this study was to determine if the SORG ML algorithm accurately predicts 90-day and 1-year survival in an external metastatic long-bone disease patient cohort.

METHODS

A retrospective review of 264 patients who underwent surgery for long-bone metastases between 2003 and 2019 was performed. Variables used in the stochastic gradient boosting SORG algorithm were age, sex, primary tumor type, visceral/brain metastases, systemic therapy, and 10 preoperative laboratory values. Model performance was calculated by discrimination, calibration, and overall performance.

RESULTS

The SORG ML algorithms retained good discriminative ability (area under the cure [AUC]: 0.83; 95% confidence interval [CI]: 0.76-0.88 for 90-day mortality and AUC: 0.84; 95% CI: 0.79-0.88 for 1-year mortality), calibration, overall performance, and decision curve analysis.

CONCLUSION

The previously developed ML algorithms demonstrated good performance in the current study, thereby providing external validation. The models were incorporated into an accessible application (https://sorg-apps.shinyapps.io/extremitymetssurvival/) that may be freely utilized by clinicians in helping predict survival for individual patients and assist in informative decision-making discussion before operative management of long bone metastatic lesions.

Is local recurrence in bone and soft tissue sarcomas just a local recurrence or does it impact the overall survival, retrospective cohort from a sarcoma referral center

BACKGROUND AND OBJECTIVES

Sarcoma local recurrence (LR) is often associated with metastasis, but it is unclear if LR can be a causal event leading to metastasis. We question if LR is best viewed as an independent oncologic event or as a worrisome harbinger threatening a patient's overall survival.

METHODS

We identified patients with LR and/or metastasis from an ongoing cohort of 629 patients with primary sarcoma and performed a detailed review to assess the timing of metastasis resulting in the following groups: (1) Isolated LR, (2) LR before metastasis, (3) LR within 6 months of metastasis, (4) LR 6-12 months after metastasis, (5) LR >12 months after metastasis, and (6) metastasis at diagnosis.

RESULTS

Overall, 43 patients met the inclusion criteria with an LR rate of 7%. Ten patients (2% of the entire cohort, 23% of LR) developed an LR before or within 6 months of metastasis. For patients without systemic disease preceding LR, 3 of 23 soft tissue sarcoma STS (13%) and 7 of 10 bone sarcoma (70%) subsequently developed metastasis (p < 0.01).

CONCLUSION

LR with subsequent metastasis is a rare event. LR appears to be best viewed as a marker of tumor aggressiveness rather than the cause of metastasis and poor survival. LR in bone sarcoma patients should warn providers of a high risk of imminent metastasis.

What is the likelihood of nonpulmonary metastasis occurring in the absence of lung metastasis in bone and soft tissue sarcoma? A nested case-control from a sarcoma referral centre

BACKGROUND AND OBJECTIVES

Nonpulmonary metastases (NPM) are rare, associated with a poorer prognosis, and maybe missed on conventional chest imaging for sarcoma surveillance. We determined (1) the proportion of NPM occurring in isolation or with synchronous or prior pulmonary metastases (PM), and (2) if initial NPM would have been recognized with a standard surveillance protocol.

METHODS

Investigators identified patients who developed initial NPM without prior evidence of or concurrent PM from an ongoing cohort of bone and soft tissue sarcoma (STS) patients. Logistic regression at univariate level was done.

RESULTS

There were 138/630 (22%) patients with metastasis and 66 (10%) had NPM: 50 (8%) patients had PM presenting first, while 16 (3%) had initial NPM. Malignant peripheral nerve sheath tumor, angiosarcoma, rhabdomyosarcoma, synovial sarcoma, and myxoid liposarcoma were six times more likely to develop initial NPM than other subtypes of STS with odds ratio = 6 (95% confidence interval: 1.93-18.65, p value < 0.01). Chest imaging and physical examination were sufficient to identify NPM in all except three bone sarcoma patients.

CONCLUSIONS

Patients who develop initial NPM are rare and demonstrate a predilection towards some subtypes of extremity sarcoma. They develop oligometastatic disease, which may be amenable for surgical excision. All isolated or initial NPM in STS patients were discovered by physical examination and standard chest imaging.

Intratumoral talimogene laherparepvec injection with concurrent preoperative radiation in patients with locally advanced soft-tissue sarcoma of the trunk and extremities: phase IB/II trial

Background

Soft-tissue sarcomas (STS) in the extremities and trunk treated with standard-of-care preoperative external beam radiation therapy (EBRT) followed by surgical resection are associated with local and distant relapses. In preclinical studies, oncolytic virotherapy in sarcoma has demonstrated antitumor effects via direct intratumoral oncolysis and cytotoxic T-cell–mediated immune responses. Talimogene laherparepvec (TVEC) is a replication-competent, immune-enhanced, oncolytic herpes simplex virus type 1 engineered for intratumoral injection; it has been approved by the FDA for the treatment of locally advanced and metastatic melanoma.

Methods

We explored a novel combination of TVEC with standard-of-care EBRT administered preoperatively in patients with locally advanced STS of the extremities and trunk in a phase IB/II clinical trial. Thirty patients with primary STS >5 cm for which EBRT was indicated to achieve negative margins were enrolled. FDA-approved TVEC doses were used. Immune correlative studies in peripheral blood, biopsy and resected tumor tissues were performed.

Results

No dose-limiting toxicity was observed. Adverse events were similar to those reported in prior studies with TVEC. One patient with myxoid liposarcoma exhibited a partial response. Seven of the 29 (24%) evaluable patients achieved 95% pathological necrosis. None of the patients developed a herpes infection due to the treatment. Eight of the 29 (27%) patients developed postoperative wound complications, which is consistent with previous studies. None of the patients developed local recurrence after surgical resection of the primary sarcoma. 2-year progression-free and overall survival were 57% and 88%, respectively. Caspase-3 demonstrated increased expression of both in TVEC-treated tissue samples as compared with control samples treated with radiation alone.

Conclusion

Preoperative intratumoral TVEC with concurrent EBRT for locally advanced STS is safe and well-tolerated. This combination treatment may enhance immune responses in some cases but did not increase the proposed rate of pathological necrosis. The Caspase-3 biomarker may be associated with a positive effect of TVEC in sarcoma tumor tissue and should be explored in future studies.

Trial registration number

NCT02453191.

Skeletal Related Events are Rare After Radiation Treatment for Metastatic Disease of the Femur

BACKGROUND

Pain is a common presenting symptom in patients with metastatic disease to the femur (MDF), and it is often difficult to differentiate pain from the tumor itself versus pain from an impending pathologic fracture. Radiation therapy (RT) is commonly used in the management of pain secondary to MDF but is not adequate in isolation when the underlying bone is structurally compromised.

QUESTIONS/ PURPOSES

The purposes of this study were to determine 1) the incidence of skeletal related events (SREs) following RT to the femur, 2) the frequency and implications of orthopedic evaluation prior to RT, and 3) the frequency of patients presenting with a pathologic fracture.

METHODS

A retrospective, single-institution review of 86 patients with MDF treated with RT from 2005 to 2018 was performed. Patient demographics, primary cancer type, pathologic fracture, orthopedic interventions, and RT details were assessed. Patients were followed to evaluate the occurrence of skeletal related events of the femur until death or time of last recorded clinical follow-up.

RESULTS

In our cohort of 86 patients, the mean RT dose was 22.3 Gy (8-55.8 Gy) delivered over 6.5 fractions (1-31 fractions). Fifteen patients (17%) received RT less than one month, 30 (35%) less than three months, and 49 (57%) less than six months prior to death. Prior to RT, 42 patients (48.9%) had an orthopedic evaluation, 16 of which (38.1% of those evaluated) received prophylactic stabilization with an intramedullary nail (IMN). Ten patients (11.6%) presented with a pathologic fracture. Following RT, five patients (5.8%) had at least one SRE. Three patients sustained a pathologic fracture, three required repeat RT, and three required further surgical intervention.

CONCLUSION

Metastatic disease of bone is a common condition that affects many cancer patients. In our institution's series of MDF treated with RT, we only found one patient who sustained a pathologic fracture after RT treatment with an unrecognized impending fracture. As only half of the patients were referred for an orthopedic evaluation prior to RT, continued education of medical and radiation oncologists regarding the signs and symptoms of impending pathologic fracture is warranted.Level of Evidence: IV.

Acceptance and Commitment Therapy Delivered via a Mobile Phone Messaging Robot to Decrease Postoperative Opioid Use in Patients With Orthopedic Trauma: Randomized Controlled Trial

BACKGROUND

Acceptance and commitment therapy (ACT) is a pragmatic approach to help individuals decrease avoidable pain.

OBJECTIVE

This study aims to evaluate the effects of ACT delivered via an automated mobile messaging robot on postoperative opioid use and patient-reported outcomes (PROs) in patients with orthopedic trauma who underwent operative intervention for their injuries.

METHODS

Adult patients presenting to a level 1 trauma center who underwent operative fixation of a traumatic upper or lower extremity fracture and who used mobile phone text messaging were eligible for the study. Patients were randomized in a 1:1 ratio to either the intervention group, who received twice-daily mobile phone messages communicating an ACT-based intervention for the first 2 weeks after surgery, or the control group, who received no messages. Baseline PROs were completed. Two weeks after the operative intervention, follow-up was performed in the form of an opioid medication pill count and postoperative administration of PROs. The mean number of opioid tablets used by patients was calculated and compared between groups. The mean PRO scores were also compared between the groups.

RESULTS

A total of 82 subjects were enrolled in the study. Of the 82 participants, 76 (38 ACT and 38 controls) completed the study. No differences between groups in demographic factors were identified. The intervention group used an average of 26.1 (SD 21.4) opioid tablets, whereas the control group used 41.1 (SD 22.0) tablets, resulting in 36.5% ([41.1-26.1]/41.1) less tablets used by subjects receiving the mobile phone-based ACT intervention (P=.004). The intervention group subjects reported a lower postoperative Patient-Reported Outcome Measure Information System Pain Intensity score (mean 45.9, SD 7.2) than control group subjects (mean 49.7, SD 8.8; P=.04).

CONCLUSIONS

In this study, the delivery of an ACT-based intervention via an automated mobile messaging robot in the acute postoperative period decreased opioid use in selected patients with orthopedic trauma. Participants receiving the ACT-based intervention also reported lower pain intensity after 2 weeks, although this may not represent a clinically important difference.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03991546; https://clinicaltrials.gov/ct2/show/NCT03991546.

Nonoperative Treatment of a Pathologic Proximal Tibia Fracture in the Setting of Previous Total Knee Arthroplasty: A Case Report

CASE

We present the case of a super obese 51-year-old woman with a pathologic fracture of the proximal tibia in the setting of a previous total knee arthroplasty. Imaging demonstrated an osteolytic lesion distal to the keel and pathologic fracture of the proximal tibia. Nonoperative treatment with a 12-week course of nonweight-bearing resulted in fracture healing and ossification of osteolysis.

CONCLUSION

Pathologic fractures of the tibia secondary to osteolysis are frequently treated surgically. Patients may benefit from nonoperative management, even in the setting of super morbid obesity and significant osteolysis about the tibial component.

Simulated lesions representative of metastatic disease predict proximal femur failure strength more accurately than idealized lesions

Metastatic disease in bone is characterized by highly amorphous and variable lesion geometry, with increased fracture risk. Assumptions of idealized lesion geometry made in previous finite element (FE) studies of metastatic disease in the proximal femur may not sufficiently capture effects of local stress/strain concentrations on predicted failure strength. The goal of this study was to develop and validate a FE failure model of the proximal femur incorporating artificial defects representative of physiologic metastatic disease. Data from 11 cadaveric femur specimens were randomly divided into either a training set (n = 5) or a test set (n = 6). Clinically representative artificial defects were created, and the femurs were loaded to failure under offset torsion. Voxel-based FE models replicating the experimental setup were created from the training set pre-fracture computed tomography data. Failure loads from the linear model with maximum principal strain failure criterion correlated best with the experimental data (R² = 0.86, p = 0.024). The developed model was found to be reliable when applied to the test dataset with a relatively low RMSE of 46.9 N, mean absolute percent error of 12.7 ± 17.1%, and cross-validation R² = 0.88 (p < 0.001). Models simulating realistic lesion geometry explained an additional 26% of the variance in experimental failure load compared to idealized lesion models (R² = 0.62, p = 0.062). Our validated automated FE model representative of physiologic metastatic disease may improve clinical fracture risk prediction and facilitate research studies of fracture risk during functional activities and with treatment interventions.

Sarcopenia is associated with increased mortality but not complications following resection and reconstruction of sarcoma of the extremities

BACKGROUND AND OBJECTIVES

Evidence regarding the impact of sarcopenia on operative outcomes in patients with sarcoma is lacking. We evaluated the relationship between sarcopenia and postoperative complications or mortality among patients undergoing tumor excision and reconstruction. ​ METHODS: We retrospectively reviewed 145 patients treated with tumor excision and limb reconstruction for sarcoma of the extremities. Sarcopenia was defined as psoas index (PI) < 5.45 cm² /m² for men and <3.85 cm² /m² for women from preoperative axial CT. Regression analyses were used to assess the association between postoperative complications or mortality with PI, age, gender, race, body mass index, tumor histology, grade, depth, location, size, and neoadjuvant/adjuvant therapy.

RESULTS

There were 101 soft tissue tumors and 44 primary bone tumors. Sarcopenia was present in 38 patients (26%). Sarcopenic patients were older (median age: 72 vs 59 years, P = .0010) and had larger tumors (86.5%, >5 cm vs 77.7%, P = .023). Seventy-three patients experienced complications (51%) and 18 patients died within 1 year. Sarcopenia and metastatic disease were associated with increased 12-month mortality (hazard ratio [HR] = 6.68, P < .001; HR: 8.51, P < .001, respectively) but not complications (HR 1.45, P = .155, odds ratio, 1.32, P = .426, respectively).

CONCLUSIONS

Sarcopenia and metastatic disease were independently associated with postoperative mortality but no complications following surgery.

Video-assisted thoracoscopic surgery for ectopic mediastinal parathyroid adenoma

Background

Primary hyperparathyroidism (PHPT), caused by an ectopic mediastinal parathyroid adenoma, is uncommon. In the past, when the adenoma was not accessible from the neck, median sternotomy was advocated for safe and successful parathyroidectomy. Video‐assisted thoracoscopic surgical (VATS) parathyroidectomy represents a modern alternative approach to this problem.

Methods

Information on patients undergoing VATS was obtained from a specific database, including clinical presentation, biochemistry, preoperative imaging, surgical approach and patient outcomes. A comprehensive literature review was undertaken to draw comparisons with other publications.

Results

Over a 2‐year period, nine patients underwent VATS parathyroidectomy for sporadic PHPT. Five patients had persistent PHPT following previous unsuccessful parathyroidectomy via cervicotomy, and four had had no previous parathyroid surgery. The median duration of surgery was 90 (range 60–160) min. Eight patients were cured biochemically, with no major complications. One patient required conversion to a median sternotomy for removal of a thymoma that had resulted in false‐positive preoperative imaging.

Conclusion

With appropriate preoperative imaging, multidisciplinary input and expertise, VATS parathyroidectomy is an effective, safe and well tolerated approach to ectopic mediastinal parathyroid adenoma.

What Is the Clinical Importance of Incidental Findings on Staging CT Scans in Patients With Sarcoma?

BACKGROUND

Baseline staging CT scans are performed on nearly every patient after the diagnosis of a sarcoma to evaluate for the presence of metastatic disease. These scans often identify abnormalities that may or may not be related to the known malignancy. Despite the high frequency of incidental findings, there is little guidance for clinicians faced with assessing these radiographic abnormalities. The interpretation of incidental findings is important because it may influence decisions regarding surveillance frequency, prognostic estimation, and surgical and medical intervention.

QUESTIONS/PURPOSES

The purpose of this study was to determine (1) the frequency of abnormal findings and indeterminate nodules on staging CT scans; (2) the natural history of indeterminate nodules identified at the time of sarcoma diagnosis; and (3) the factors associated with indeterminate nodules representing true metastatic disease.

METHODS

Between September 2010 and February 2016 we treated 233 patients with bone and soft tissue sarcomas. Of those, 227 (97%) had a staging CT scan of the chest or chest/abdomen/pelvis performed within 2 months of diagnosis. To be eligible for this retrospective study, a patient had to have a minimum of 6 months of radiographic followup after that initial CT scan. A total of 36 (16%) were lost to followup or did not have radiographic surveillance at least 6 months later, and 48 (21%) were excluded for other prespecified reasons, leaving 149 patients for evaluation. We recorded all abnormal findings listed in the official radiology CT report of the lung, bone, liver, and lymph nodes. We assessed progression of indeterminate nodules by reviewing radiology reports, which listed both size and number of findings, and clinical notes outlining the current assessment of disease status and treatment plan. If indeterminate nodules grew in size or number consistent with metastatic disease or were confirmed histologically, they were considered to represent true metastasis. Bivariate methods were used to investigate an association between various clinical factors, which were obtained from chart review, and progression of indeterminate nodules to clear metastatic disease.

RESULTS

One hundred thirty-five of 149 patients (91%) had at least one abnormal finding on a staging CT scan. Forty-nine patients (33%) presented with indeterminate lung nodules, 15 (10%) with indeterminate liver lesions, four (3%) with indeterminate bone lesions, and 57 (38%) with enlarged lymph nodes. Fifteen of the 49 patients with indeterminate lung nodules (31%), one of 15 liver nodules, zero of four bone lesions, four of 13 lymph nodes 1 to 2 cm in size, and two of 44 subcentimeter lymph nodes (4.5%) were clearly metastatic on followup. A primary tumor size ≥ 14 cm in greatest dimension was more suggestive of indeterminate nodules representing true metastatic disease compared with smaller primary tumors in both lung (eight of 10 compared with seven of 36 [19%]; odds ratio, 16.6; 95% confidence interval, 2.9-95.9; p < 0.001) and lymph nodes (six of 18 compared with zero of 36 [0%], p < 0.001).

CONCLUSIONS

It is extremely common for abnormal findings and incidental nodules to be present at the time of a staging CT scan in patients with sarcoma. Although patients with indeterminate nodules should have continued surveillance, it appears from this study that the majority of these findings do not represent true metastatic disease. Given a minimum followup of 6 months, it is possible the actual proportion of indeterminate lesions representing true metastatic disease may increase over time.

LEVEL OF EVIDENCE

Level III, prognostic study.

Epidemiology, Therapeutic Strategies, Outcomes, and Complications of Pathologic Fractures

Much can be learned about the epidemiology of metastatic disease of bone through large databases. Secondary data analyses add substantial knowledge of the incidence, prevalence, cost, complications, risk factors, and treatment variability by using modern statistical methods in a large patient cohort. Investigators must be aware of the intentions of these data sources as well as the limitations in any conclusions drawn. Large databases are primarily beneficial in generating hypotheses and will likely continue to be an important source of information. For the general orthopaedist, surgical management of metastatic skeletal disease can be a challenging problem with many potential risks. Complications are often encountered and can be influenced by the patient's medical conditions, stage of disease, and the selected surgical procedure. Patients diagnosed with skeletal metastases are often at higher risk of having perioperative complications, such as infection and thromboembolism, than is the general population. A case-based approach highlights potential risks with examples of common scenarios that can arise.

Automated Mobile Phone Messaging Utilizing a Cognitive Behavioral Intervention: A Pilot Investigation

BACKGROUND

In the setting of outpatient orthopaedic surgery, this pilot study utilized automated mobile messaging to assess (1) the feasibility of and interaction rates with a software delivered cognitive behavior therapy (CBT) intervention for postoperative opioid utilization, (2) the reliability of patient reported opioid utilization through our platform, (3) daily patient reported pain and opioid utilization within the first two postoperative weeks, and (4) the effect of software delivered CBT intervention on patient reported opioid utilization.

METHODS

Musculoskeletal tumor patients scheduled for outpatient surgery were randomized into two study groups. Control patients received standard postoperative communication limited to a two-week postoperative follow-up visit. The intervention group received automated daily text-messages regarding pain, opioid utilization, and a daily CBT intervention. Interventional group patients also completed a patient satisfaction questionnaire at their two-week follow-up. Completion rates of all software delivered questions were determined in the interventional group. Median values of opioid utilization and interquartile range (IQR) were determined to compare utilization between groups. Spearman correlation coefficients were used to determine reliability of patient reported opioid utilization in the interventional group.

RESULTS

Fourteen patients completed the pilot study (seven controls, seven intervention). Patients in the intervention arm completed 90% of pain and opioid questions. Intervention group patients utilized less of their daily prescribed opioid medication (20%, IQR:10%-27%) compared to controls (50%, IQR:4%-68%). Correlation between in-office pill counts and patient reported opioid medication utilization via our software messaging system was high (r=0.90, p=0.037).

CONCLUSION

Automated mobile phone messaging in outpatient tumor surgery yielded high interaction rates. Patient reported opioid utilization obtained through our platform demonstrated a high correlation with in-office pill counts. CBT delivered via automated mobile phone messaging demonstrated decreased opioid utilization in this pilot investigation.Level of evidence: II.

Radiographic Enchondroma Surveillance: Assessing Clinical Outcomes and Costs Effectiveness

BACKGROUND

Enchondromas are a common long bone benign tumor often discovered incidentally on imaging for adjacent pathology. These benign cartilaginous tumors can be difficult to differentiate from low-grade chondrosarcomas on imaging and histology. Multiple advanced imaging studies and clinic visits are required to confirm stability. Surveillance for these lesions can lead to significant patient costs without a clear oncologic or functional benefit. There is a lack of evidence-based consensus guidelines for the surveillance of enchondromas. The purposes of our study are: 1) to determine the number and proportion of low-grade cartilaginous tumors that demonstrate growth or require treatment and 2) to optimize the efficacy and cost-effectiveness of surveillance strategies for detecting biologically active lesions.

METHODS

A retrospective single-institution study was performed on 55 subjects, 18 years or older, with long bone enchondromas without concerning radiographic characteristics that were referred to our institution's orthopaedic oncology clinic from July 1, 2009 to November 30, 2016. All subjects had at least 12 months of radiographic follow-up. We performed a chart and imaging review to assess for growth of the lesion over time. The number of pre-referral imaging and the number of follow-up imaging studies were recorded. The costs of plain radiographs and advanced imaging were estimated using our institution's global charge list in 2016.

RESULTS

For stable enchondromas, 35 out of 52 lesions (67.3%) presented in the lower extremities compared to three out of three (100%) growing cartilaginous tumors. Three out of 55 (5.45%) long bone cartilaginous lesions exhibited growth at a median of 23 (range 21-25 months) follow-up. There was no apparent difference in median presenting age for stable versus growing lesions (58.5 versus 55.0 years old, p =0.5673) or median lesion size at presentation (4.1 cm versus 3.6 cm, p = 0.2923). None of these lesions presented with pain attributable to the lesion. One out of seven biopsied cartilaginous lesions (four stable and three growing) had a histology diagnosis of grade 1 chondrosarcoma. There was no significant difference in the median number of total clinical visits for stable (four) and growing (five) enchondromas (p = 0.0807). The median pre-referral costs per patient were: plain radiographs ($383.00), CT scans ($0.00), and MRI imaging ($3,969.00). The median post-referral costs for plain radiographs and MRI per patient were $1,326.00 and $4,668.00, respectively. The annual median costs for plain radiographs and MRI were $609.23 and $2,240.64, respectively.

DISCUSSION

In conclusion, enchondroma growth was a rare event and typically occurred at two years follow-up in our series. Given the low risk for malignant transformation, we propose surveillance with plain radiographic follow-up for stable enchondromas every 3-6 months for the first year and then annually for at least three years of total follow-up. The most significant costs savings can be made by limiting MRI imaging in the absence of clinical or radiographic concern. Additional studies are needed to determine the long-term risk of growth or declaration of chondrosarcoma.Level of Evidence: IV.

Risk factors for detectable metastatic disease at presentation in Ewing sarcoma - An analysis of the SEER registry

BACKGROUND

Ewing family of tumors (EFT) represents the second-most common primary bone malignancy in children and adolescents. Approximately 25% of patients have radiographically detectable metastatic disease at presentation and experience poorer five-year survival, yet risk factors for metastatic disease at presentation are poorly characterized. We sought to study patient characteristics associated with metastatic disease upon presentation for patients with EFT.

METHODS

We identified EFT cases in the Surveillance, Epidemiology, and End Results Program (SEER) registry from 2004 to 2012. Using univariate analyses and multivariable logistic regression, we explored the relationship between demographic and clinical factors and the presence of detectable metastatic disease at presentation.

RESULTS

Among 870 EFT cases, 35% (n = 304) presented with detectable metastatic disease. These patients were commonly older (>24 years: 28% vs 19%, p = 0.002) and had a primary tumor site in the axial skeleton (56% vs 44%, p < 0.001). After adjusting for all covariates, compared to patients <11 years, those >24 years old faced a two-fold increase in the odds of metastatic disease (OR = 1.99, 95% CI: 1.17-3.38). Axial (OR = 2.31, 95% CI: 1.58-3.37) and "other" (OR = 2.35, 95% CI: 1.15-4.81) tumor locations had more than twice the likelihood of presenting with metastatic disease, compared to extremity tumor sites. Increasing tumor size conferred up to a three-fold increase in odds of metastatic disease (pTrend <0.001).

CONCLUSIONS

Advanced age, axial tumor location, and increasing tumor size are associated with increased odds of detectable metastatic disease upon presentation with EFT. Although these characteristics are not modifiable, they provide objective factors that may inform patient counseling of metastatic risk.

Improved survival for extremity soft tissue sarcoma treated in high-volume facilities

BACKGROUND AND OBJECTIVES

The purpose of this investigation was to determine the effect of hospital volume on treatment decisions, treatment results, and overall patient survival in extremity soft tissue sarcoma.

METHODS

The National Cancer Database was used to identify patients ≥18 years of age with non-metastatic soft tissue sarcoma of the extremity treated with surgery. Patients in high- and low-volume centers were matched by propensity score and placed into two equal comparative groups of 2437 patients each.

RESULTS

Chemotherapy was used at a higher rate in high-volume centers (22% vs 17%, P < 0.001) and external beam radiation usage was similar (55% vs 52%, P = 0.108). There was a lower incidence of positive margins in high-volume centers (12% vs 17%, P < 0.001). There was no significant difference in the rates of limb salvage surgery or readmissions at high-volume hospitals compared to low-volume. In a multivariate Cox proportional hazards model, low-volume facilities demonstrated diminished overall survival at all time points (hazard ratio at 5 years = 1.24, 95%CI 1.10-1.39).

CONCLUSIONS

Treatment at high-volume hospitals was associated with fewer positive margins and increased overall survival at 2, 5, and 10 years. Continued efforts should focus on optimizing the balance between patient access to specialty care and experience of the treating center.

No consensus on implant choice for oligometastatic disease of the femoral head and neck

Objectives

Metastatic disease involving the femoral head and neck is often treated with a hemiarthroplasty or total hip arthroplasty (THA) to prevent pathologic fracture but there are no outcome studies demonstrating superiority of one option over the other.

Methods

This investigation was designed as a survey of the current members of the Musculoskeletal Tumor Society (MSTS). The survey contained seven clinical vignettes with identical imaging of a pathologic lesion of the femoral head and neck. The primary outcome measured was decision to treat the lesion with hemiarthroplasty or THA. Secondary outcomes included method of fixation of the femoral/acetabular components and head type utilized.

Results

A total of 93 members (30.0%) of the MSTS completed the survey. Across all clinical vignettes, 73.3% (p < 0.001) of the responses were in favor of hemiarthroplasty; however, there was no significant difference between hemiarthroplasty and THA in Cases 1 & 2 (p = 0.08, p = 0.6, respectively); the cases representing younger patients with a more favorable histologic diagnosis. When THA was selected the majority of respondents preferred hybrid or cementless fixation construct (56.1% and 27.0%, respectively, p < 0.001). When hemiarthroplasty was selected respondents selected a cemented, bipolar construct (86.4% and 64.2%, respectively, p < 0.001).

Conclusions

When treating metastatic lesions of the femoral head and neck orthopaedic oncologists do not agree on reconstructing with THA versus hemiarthroplasty for patients with younger age and favorable histology. This investigation highlights the controversy of this clinical decision and indicates the need for a collaborative prospective trial among this specific patient population in order to determine the optimal treatment method.

The Significance of a "Close" Margin in Extremity Sarcoma: A Systematic Review

BACKGROUND

An important measure of successful sarcoma treatment is the surgical tumor margin, yet defining and reporting the tumor margin has remained a source of controversy. Our study sought to determine whether there is a need to be more specific in classifying a margin by distinguishing a 'close' margin, or if simply calling a margin positive or negative is sufficient.

METHODS

We performed a comprehensive literature search in which all studies were reviewed independently by two separate reviewers. Studies eligible for inclusion and data analysis consisted of those that reported on at least ten patients with a primary sarcoma of the extremities who received limb-salvage or amputation surgery with a report of the final surgical margin as well as the histologic grade. Only studies that provided local recurrence outcomes with a minimum follow-up of two years were included.

RESULTS

Our literature search and article exclusion process resulted in 22 articles that contained 498 patients for data analyses. We found that the Enneking classification system distinguishes between intralesional, marginal, and wide/ radical margins, and that a close margin behaves closer to a positive margin than a negative margin. When all tumors were analyzed, a marginal margin gave a recurrence rate of 50.48% compared to an intralesional margin recurrence rate of 75.76% and a wide/ radical margin of 7.22%. A marginal margin set to a positive margin gave the highest sensitivity compared to comparing marginal margins to wide and intralesional margins alone. This was also observed when tumors were stratified into high-grade osteosarcomas treated with chemotherapy. In addition, we found that chemotherapy dramatically reduced local recurrence rates in osteosarcoma.

CONCLUSIONS

Our literature search and data analysis showed that the Enneking classification system was able to give more information on local recurrence compared to a simple dichotomous system, and therefore may be considered a more successful predictor of treatment outcomes. As a result, this investigation may lead a suggestion of a practice-changing proposal of how surgical margins in sarcoma should be reported universally amongst multiple disciplines and institutions.Level of Evidence: II.

What are the Results of Surgical Treatment of Postoperative Wound Complications in Soft Tissue Sarcoma? A Retrospective, Multi-Center Case Series

BACKGROUND

Non-oncologic wound complications are common following resection of soft tissue sarcomas and factors predisposing to the development of complications have been extensively studied. To our knowledge, the methods and results of surgical treatment of these complications have not been reported. The purposes of this study were to 1) identify time to recognition, treatment employed, and eventual outcome of complications 2) investigate risk factors that may predispose patients to failure in management of complications following resection of soft tissue sarcomas.

METHODS

This was a multi-institutional, retrospective case series of patients treated with a primary closure of a limb sparing resection of a soft tissue sarcoma of the pelvis or extremity who developed a non-oncologic wound complication requiring operative intervention. The primary outcomes were a healed wound at the end of treatment and the total number of procedures required to address the complication.

RESULTS

There were 61 patients from 11 institutions included in the analysis. The median time from surgery to the initial recognition of a complication was 22 days (range 0-173 days), with 51 patients (84%) presenting in the first six weeks postoperatively. The definitive procedures included primary closure (44), healing by secondary intention (9), muscle flap (6), and skin graft (2). No patient was treated with an amputation. Six patients (10%) had a wound requiring continued dressing changes. 12 patients (20%) required at least one (range 1-4) additional unplanned procedure. In a bivariate analysis, we found patients with an infection were at increased risk of requiring multiple unplanned procedures (p=0.024).

CONCLUSION

Limb sparing resection of a soft tissue sarcoma is known to be at high risk of postoperative wound complications. We found that complications uncommonly present greater than six weeks after initial treatment and surgical management predictably results in retention of the affected limb and a healed wound in those requiring operative treatment.Level of Evidence: 4 - Case Series.

Might Doctors Really "Know Best"?: Utilizing Surgeon Intuition to Strengthen Preoperative Surgical Risk Assessment

BACKGROUND

Many clinical factors are known to increase an individual patient's risk of perioperative complications and hospital readmission. Several novel risk calculators have been created to predict the risk of postoperative complications for specific procedures that rely entirely on objective measurements. Our goal was to determine if surgeon intuition (an estimate of the percent likelihood of minor and major medical and surgical complications and 30-day readmission) could provide an additional source of data in the preoperative setting that may enhance the prediction of complications after surgery.

METHODS

We targeted the operative practices of three subspecialized orthopedic surgeons over a 6-month period (February 1 to July 31, 2015). We administered surveys to attending surgeons and assisting residents or nurse practitioners prior to each operation. Surgeons were asked to predict each patient's likelihood, on a scale from <1-100, for experiencing a complication. Following the procedure, we analyzed each patient's electronic medical record to determine any adverse events and readmissions. We then looked at levels of association between predictor variables and complications. Analysis of maximum likelihood estimates for complication outcome was performed comparing objective variables and surgeon prediction.

RESULTS

A total of 417 surveys in 270 patients were available for analysis. Defining the predicted likelihood of minor medical complications as <10% (low), 10-40% (intermediate), and >40% (high), provided discrimination of postoperative complications for a single observer in the first three month. These cutoff ranges showed inter-observer consistency and a trend towards intra-observer consistency. The only three variables predictive of minor medical complications were ASA class (OR=3.63, 95%CI=1.76-7.52, p=0.0005; comparing >2 vs ≤2), age (β=0.034±0.012, p=0.0032) and surgeon prediction when comparing high to low risk (β=0.034±0.008 (0.018-0.049), p<0.0001).

CONCLUSIONS

Quantitative surgeon preoperative risk assessment was able to accurately discriminate between low- and high-risk groups of minor medical complications. We did not find a similar association between major complications and readmissions.Level of Evidence: IV.

TAZ and YAP are frequently activated oncoproteins in sarcomas

TAZ (WWTR1) and YAP are transcriptional coactivators and oncoproteins inhibited by the Hippo pathway. Herein we evaluate 159 sarcomas representing the most prevalent sarcoma types by immunohistochemistry for expression and activation (nuclear localization) of TAZ and YAP. We show that 50% of sarcomas demonstrate activation of YAP while 66% of sarcomas demonstrate activated TAZ. Differential activation of TAZ and YAP are identified in various sarcoma types. At an RNA level, expression of WWTR1 or YAP1 predicts overall survival in undifferentiated pleomorphic sarcoma and dedifferentiated liposarcoma. Immunohistochemistry demonstrates that TAZ and YAP expression and activation are positively correlated with grade in the well-differentiated liposarcoma to dedifferentiated liposarcoma tumor progression sequence as well as conventional chondrosarcomas. TAZ and YAP are constitutively activated oncoproteins in sarcoma cell lines. Knock-down of TAZ and YAP demonstrate differential activity for the two proteins. Verteporfin decreases colony formation in soft agar as well as CTGF expression in sarcoma cell lines harboring activated TAZ and YAP.

Obesity Does Not Exacerbate the Protumorigenic Systemic Environment in Sarcoma Subjects

Sarcomas are a rare but fatal tumor type that accounts for <1% of adult solid malignancies and ~15% of childhood malignancies. Although the use of immunotherapy is being actively investigated for other solid tumors, advances in immunotherapy for sarcoma patients are lacking. To better understand the systemic immune environment in sarcoma patients, we performed a detailed multiplex analysis of serum cytokines, chemokines, and protumorigenic factors from treatment-naive subjects with localized, high-grade sarcoma. Because obesity is a major healthcare issue in the United States, we additionally examined the effects of obesity on serum protein profiles in our sarcoma subject cohort. We found that the systemic host environment is profoundly altered to favor tumor progression, with epidermal growth factor, angiopoietin-2, vascular endothelial growth factor A, IL-6, IL-8, and MIP-1β all increased relative to tumor-free controls (all p < 0.05). Surprisingly, we found that obesity did not exacerbate this protumorigenic profile, as epidermal growth factor and IL-8 decreased with increasing subject body mass index (both p < 0.05 versus normal or overweight subjects). The Th2-related cytokines IL-4, IL-5, and IL-13 were also decreased in the presence of obesity. Thus, although the systemic environment in sarcoma subjects favors tumor progression, obesity does not further aggravate the production of protumorigenic factors.

Peripheral cytokine and chemokine alterations in depression: a meta-analysis of 82 studies

OBJECTIVE

To conduct a systematic review and meta-analysis of studies that measured cytokine and chemokine levels in individuals with major depressive disorder (MDD) compared to healthy controls (HCs).

METHOD

The PubMed/MEDLINE, EMBASE, and PsycINFO databases were searched up until May 30, 2016. Effect sizes were estimated with random-effects models.

RESULT

Eighty-two studies comprising 3212 participants with MDD and 2798 HCs met inclusion criteria. Peripheral levels of interleukin-6 (IL-6), tumor necrosis factor (TNF)-alpha, IL-10, the soluble IL-2 receptor, C-C chemokine ligand 2, IL-13, IL-18, IL-12, the IL-1 receptor antagonist, and the soluble TNF receptor 2 were elevated in patients with MDD compared to HCs, whereas interferon-gamma levels were lower in MDD (Hedge's g = -0.477, P = 0.043). Levels of IL-1β, IL-2, IL-4, IL-8, the soluble IL-6 receptor (sIL-6R), IL-5, CCL-3, IL-17, and transforming growth factor-beta 1 were not significantly altered in individuals with MDD compared to HCs. Heterogeneity was large (I² : 51.6-97.7%), and sources of heterogeneity were explored (e.g., age, smoking status, and body mass index).

CONCLUSION

Our results further characterize a cytokine/chemokine profile associated with MDD. Future studies are warranted to further elucidate sources of heterogeneity, as well as biosignature cytokines secreted by other immune cells.

Are Recently Trained Tumor Fellows Performing Less Tumor Surgery? An Analysis of 10 Years of the ABOS Part II Database

BACKGROUND

The majority of orthopaedic trainees pursue additional subspecialty training at the conclusion of residency. Although national trends indicate that fellowship-trained surgeons are more frequently performing cases in their defined subspecialties, this may not be the case for recently trained tumor fellows. Prior work has established that low tumor case volume is a significant stressor for recently trained tumor fellows. Given the relative rarity of musculoskeletal tumors, it is important for prospective trainees to have clear expectations for the proportion of specialty-specific procedures early during their careers. In addition, knowledge of anticipated specialty case volume is important to optimize fellowship training and to provide guidance for meeting the public health requirements for orthopaedic oncology.

QUESTIONS/PURPOSES

We wished to determine (1) the number of examinees who self-reported tumor fellowship training during the last decade; (2) how many tumor fellowship-educated surgeons did an additional fellowship(s) in other subspecialties; (3) the number and proportion of tumor, trauma, adult reconstruction, and other procedures performed by tumor-trained fellows; and (4) changes in the proportion of procedures performed by tumor-trained fellows during the 10-year period of the study.

METHODS

The American Board of Orthopaedic Surgery Part II database was used to identify examinees who reported tumor fellowship training between 2004 and 2013. All submitted procedures were broadly categorized as "tumor," "trauma," "adult reconstruction," or "other." Annual procedure volumes were calculated and univariate analysis allowed comparison of categorized procedures during the duration of the study.

RESULTS

The median annual number of candidates reporting tumor fellowship training was 12.5 (range, 7-16). There were 28 of 118 (24%) candidates who reported additional fellowship training. A total of 14,718 procedures were performed by all candidates with tumor fellowship training during the 10-year period of the study, 42% of which were categorized as tumor procedures. Overall, only 36% of candidates reported tumor procedures making up greater than 50% of their case volume. Between 2004 to 2005 and 2012 to 2013, the proportion of tumor procedures decreased (45% versus 36%; p < 0.001), whereas the number of adult reconstruction procedures increased (9% versus 19%; p < 0.001).

CONCLUSIONS

Between 2004 and 2013, only one-third of recently trained tumor fellows had practices with tumor procedures accounting for greater than 50% of their total case volume. Furthermore, the proportion of tumor cases performed by recently trained tumor fellows decreased during the same time. The proportion of specialty-specific procedures is lower in orthopaedic oncology than other orthopaedic subspecialties, which is important information for current trainees interested in orthopaedic oncology fellowship training and for orthopaedic oncology educators. The findings in this study should serve as an initial platform for further discussion regarding the optimal number of fellowship-trained orthopaedic oncologists required to meet regional and national needs for an accessible and proficient work force.