Pseudolesions involving bone and soft tissue regarding orthopedic oncology.

Pseudolesions in bone and muscle are encountered mostly incidentally in routine imaging studies, especially due to the recent advancements on many different imaging modalities. These lesions can be categorized into the following categories: normal variants; congenital; iatrogenic; degenerative; and postoperative. In this review, we discuss the many different radiological characteristics of musculoskeletal pseudolesions that appear on imaging, which can prevent non-essential additional studies.

Treatment and Outcomes of 4,973 Unicameral Bone Cysts: A Systematic Review and Meta-Analysis.

¼ Unicameral bone cysts (UBCs) can increase the risk of pathologic fractures of both long and short bones. Although multiple treatments exist, data are conflicting regarding optimal management.¼ We sought to analyze treatment strategies for UBCs and their rates of successful treatment.¼ Success rates were analyzed according to treatment modality, with emphasis on filling techniques and/or decompression associated with curettage, and injection compounds.¼ Curettage with bone substitute and cyst decompression was identified as a highly successful technique for UBC treatment.¼ Decompressing the cyst wall after injection, regardless of the specific compound used, had a greater potential to enhance healing rates.¼ The management decision should be individually guided within the patient's context.

Is Unplanned Excision of Soft Tissue Sarcomas Associated with Worse Oncological Outcomes?-A Systematic Review and Meta-Analysis.

BACKGROUND: Soft tissue sarcomas are a group of rare neoplasms which can be mistaken for benign masses and be excised in a non-oncologic fashion (unplanned excision). Whether unplanned excision (UE) is associated with worse outcomes is highly debated due to conflicting evidence. METHODS: We performed a systematic review and meta-analysis following PRISMA guidelines. Main outcomes analyzed were five-year overall survival (OS), five-year local recurrence-free survival (LRFS), amputation rate and plastic reconstruction surgery rate. Risk ratios were used to compare outcomes between patients treated with planned and unplanned excision. RESULTS: We included 16,946 patients with STS, 6017 (35.5%) with UE. UE was associated with worse five-year LRFS (RR 1.35, p = 0.019). Residual tumor on the tumor bed was associated with lower five-year LRFS (RR = 2.59, p < 0.001). Local recurrence was associated with worse five-year OS (RR = 1.82, p < 0.001). UE was not associated with a worse five-year OS (RR = 0.90, p = 0.16), higher amputation rate (RR = 0.77, p = 0.134), or a worse plastic reconstruction surgery rate (RR = 1.25, p = 0.244). CONCLUSIONS: Unplanned excision of Soft Tissue Sarcomas and the presence of disease in tumor bed after one were associated with worse five-year LRFS. Tumor bed excision should remain the standard approach, with special consideration to the presence of residual disease.

A Bibliometric Analysis of the 500 Most Cited Papers in Orthopaedic Oncology.

BACKGROUND: Despite notable progress over time, broad insight into the scientific landscape of orthopaedic oncology is lacking. We conducted a bibliometric analysis of the 500 most cited papers in the field. METHODS: We searched the Science Citation Index Expanded database of the Web of Science Core Collection to find the 500 most cited articles in the field. RESULTS: Citation count ranged from 81 to 1,808. Articles were published from 1965 to 2018. Over half of all articles were published in the United States (53.6%). The 2000s was the most productive decade with 170 (34%) articles. All articles were written in English and were published across 29 journals. Female participation as first authors significantly increased from the 1960s to the 2010s (0% vs 14.6%, P = 0.0434). Similarly, female involvement as senior authors grew from the 1960s to the 2010s (0% vs 12.2%, P = 0.0607). Primary bone sarcomas were the most cited topic among articles from the 1970s to the 1980s. From studies produced in the 1990s up until the 2010s, reconstruction procedures were the most cited topic. CONCLUSION: Trends over the years have resulted in an emphasis on a surgical technique. Notable progress has been made regarding gender diversity, yet disparities still exist.

Subtrochanteric nonunion after intramedullary nailing due to pathological fracture: proximal femoral replacement as a salvage approach.

PURPOSE: To assess proximal femoral replacement as a treatment solution for nonunion of pathologic subtrochanteric fractures after cephalomedullary nailing in patients with pathological fracture and previously irradiated bone. METHODS: Retrospective review of five patients with pathological subtrochanteric femoral fractures that were treated with cephalomedullary nailing and developed a nonunion, which was revised with conversion to a proximal endoprosthetic replacement. RESULTS: All five patients had previously been treated with radiation. One patient had the latest follow-up at 2 months postoperatively. At that time, the patient was walking with a walker for assistance, with no evidence of hardware failure or loosening on imaging. The remaining four patients had the latest follow-up ranging from 9 to 20 months after surgery. At their latest follow-up, three of the four patients were ambulatory with no pain, using only a cane for assistance with longer distances. The other patient demonstrated pain in his affected thigh, utilizing a walker for assistance with ambulation at latest follow-up, but not requiring further surgical interventions. There were no hardware failures or implant loosening through the follow-up period. None of the patients required revision, and there were no postoperative complications observed at their last follow-up. CONCLUSIONS: In patients with pathological fractures in the subtrochanteric region that is treated with cephalomedullary nailing and developed a nonunion, treatment with conversion to a proximal femoral replacement with a mega prosthesis is a valuable treatment with good functional results and low risk for complications. LEVEL OF EVIDENCE: Therapeutic level IV.

Treatment and Outcomes of Radiation-Induced Soft Tissue Sarcomas of the Extremities and Trunk-A Systematic Review of the Literature.

INTRODUCTION: Radiation-induced soft tissue sarcomas (RISs) are rare secondary malignancies with a dire prognosis. The literature on the management of these tumors remains scarce due to their low incidence. Our systematic review sought to assess the treatment alternatives and outcomes of patients with RIS. METHODS: A systematic review was conducted following the PRISMA guidelines. Our study was registered in PROSPERO (ID: CRD42023438415). Quality assessment was performed using the STROBE checklist. Weighted means for both continuous and categorical values were calculated. RESULTS: Twenty-one studies comprising 1371 patients with RIS were included. The mean latency period from radiation to RIS diagnosis was 14 years, and the mean radiation dose delivered to the primary malignancy was 29.2 Gy. The most common histological type was undifferentiated pleomorphic sarcoma (42.2%), and 64% of all tumors were high-grade. The trunk was the most common location (59%), followed by extremities (21%) and pelvis (11%). Surgery was performed in 68% of patients and, among those with an appendicular tumor, the majority (74%) underwent limb-salvage surgery. Negative margins were attained in 58% of patients. Chemotherapy and radiotherapy were administered in 29% and 15% of patients, respectively. The mean 5-year overall survival was 45%, and the local recurrence and metastasis rates were 39% and 27%, respectively. CONCLUSIONS: In our study, the most common treatment was surgical resection, with RT and chemotherapy being administered in less than one third of patients. Patients with RIS exhibited poor oncologic outcomes. Future studies should compare RIS with de novo STS while controlling for confounders.

Postoperative Outcomes of Total Femur Replacement in Oncologic and Nononcologic Patients: A Systematic Review of the Literature.

BACKGROUND: Total femur replacement (TFR) is used for primary reconstruction after extensive tumor resection or as a revision surgery due to prosthetic failure. Studies on TFR rates of failure and functional outcomes are scarce. The purpose of our study was to compare the modes of failure, amputation rates, and functional outcomes after TFR between oncologic and nononcologic patients. METHODS: We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were for this manuscript. Our study was registered on PROSPERO (413582). Quality assessment of all studies was performed using Strengthening the Reporting of Observational Studies in Epidemiology checklist. Endoprosthesis failure was assessed using the Henderson classification and functional outcomes using the Musculoskeletal Tumor Society score. Weighted means and standard deviations were calculated. RESULTS: Overall failure rate was similar between groups. Henderson type 4 failures were more common within the nononcologic group, while the others were more frequently found in the oncologic group. Overall amputation rate was higher in the oncologic group mainly due to type 5 failure. Amputations occurred mainly after type 4 and type 5 failures. Functional outcome was better within the oncologic group (70.5 versus 61.7, respectively; P < .001). CONCLUSIONS: Total femoral replacement in the oncologic and nononcologic group is associated with a high rate of failure (31% and 32.5%, respectively). Overall amputation rate was higher in the oncologic group mainly due to type 5 failure. Functional outcome was better within the oncologic group. LEVEL OF EVIDENCE: Level III.

Hand and finger, ultrasound-guided, percutaneous core needle biopsies: A safe procedure with high diagnostic accuracy.

Introduction/Purpose: To determine the diagnostic accuracy and complication rates of ultrasound-guided, percutaneous core needle biopsies of soft tissue masses in the hand and fingers. Methods: Reports from all ultrasound-guided procedures between 21 May 2014 and 17 March 2022 were queried for keywords including "hand", OR "finger", AND "biopsy". Patient demographics, lesion size and location, biopsy needle gauge and the number of cores obtained were recorded. The final pathology of the mass excision was then compared with the core needle biopsy (CNB) for each patient. Results: Sixty-six records were reviewed, and 37 patients met inclusion criteria. Maximum lesion diameter averaged 1.45 cm with a range between 0.4 and 4.3 cm. The frequency of needle gauges used was 14G (14%), 16G (24%), 18G (38%), 20G (11%) and 'not reported' (14%). The mean number of tissue cores obtained was 2.9 (SD 1.2; range 1 to 6), excluding nine cases that reported 'multiple'. The frequency of CNB diagnoses included tenosynovial giant cell tumour (TGCT) at 30%, ganglion cyst at 11% and epidermal inclusion cyst at 5%. CNB was 100% sensitive in detecting the three (8%) malignancies. Of the 37 tumours biopsied, 16 were surgically excised. One angiomyoma was originally diagnosed as a haemangioma on CNB, but all other histologic results were concordant for a diagnostic accuracy of 97%. Discussion: Small soft tissue masses in the hands and fingers, even those less than 1 cm, are often amenable to ultrasound-guided CNB. Performance under image guidance facilitates retrieval of core specimens adquate for histologic diagnosis with relatively few passes using higher gauge needles. Conclusion: Overall, ultrasound-guided CNB of the hand and fingers is safe and highly accurate in diagnosing soft tissue tumours. The accuracy is unrelated to the needle's gauge, the number of passes and the size of the lesions.

Epidemiology and survival factors for sarcoma patients in minority populations: a SEER-retrospective study.

Background: Epidemiologic studies have demonstrated race as a predictor of worse oncological outcomes. To better understand the effect of race on oncological outcomes, we utilized the Surveillance, Epidemiology, and End Results (SEER) database to determine what treatment courses are provided to minority patients and how this impacts survival. Materials and methods: A retrospective review of bone and soft tissue sarcoma cases was performed using the SEER database for a minimum 5-year survival rate (SR) using Kaplan-Meier curves. Categorical variables were compared using Pearson's χ2 test and Cramer V. Kaplan-Meier curves were used to determine survival rates (SR) and Cox regression analysis was used to determine hazard ratios (HRs). Results: Races that had an increased risk of death included Native American/Alaska Native (NA/AN) [hazard ratio (HR): 1.36, 95% confidence interval (CI): 1.049-1.761, p = 0.020) and Black (HR = 1.17, 95% CI: 1.091-1.256, p < 0.001). NA/AN individuals had the lowest SR (5-year SR = 70.9%, 95% CI: 63.8-78.0%, p < 0.001). The rate of metastasis at diagnosis for each race was 13.07% - Hispanic, 10.62% - NA/AN, 12.77% - Black, 10.61% - Asian/Pacific Islander (A/PI), and 9.02% - White individuals (p < 0.001). There were increases in the rate of metastasis at diagnosis and decreases in rates of surgical excision for Hispanic and Black patients (p < 0.001). Conclusion: Race is determined to be an independent risk factor for death in NA/AN and Black patients with sarcomas of the extremities. Access to healthcare and delay in seeking treatment may contribute to higher rates of metastasis upon diagnosis for minority patients, and decreased rates of surgical excision could be associated with poor follow up and lack of resources.

Foot and Ankle Soft Tissue Sarcomas-Treatment and Oncologic Outcomes: A Systematic Review of the Literature.

BACKGROUND: Foot and ankle soft tissue sarcomas (STSs) are rare neoplasms associated with a high risk of local recurrence and metastasis. Although amputation is often performed, its impact on prognosis remains unknown. The aims of our systematic review were identifying risk factors for (1) disease-specific death, (2) local recurrence, (3) metastasis, and assessing (4) whether the type of surgery (amputation or limb-salvage) affected disease-specific survival. METHODS: This systematic review was conducted following PRISMA guidelines. The PubMed, Embase, and Scopus databases were searched. Our study was registered in PROSPERO (ID: 415624). Quality appraisal was done using STROBE guidelines. RESULTS: A total of 7 studies and 123 patients were included. Metastasis was the only risk factor for disease-specific death (OR = 107.85, P< .001). Previous unplanned excision (OR = 22.29, P = .009) and positive margins (OR = 64.48, P = .011) were associated with higher risk of local recurrence. Patients with high-grade tumors (OR = 13.22, P = .023) and tumors ≥6 cm (OR = 7.40, P = .022) were more likely to develop metastases. After adjusting for confounders (age, sex, and presence of metastasis), amputation was not associated with poorer disease-specific survival. CONCLUSION: Metastasis was the single most important risk factor for death with foot and ankle soft tissue sarcoma. Positive margins and history of previous unplanned excision are risk factors for local recurrence. The most important risk factors for metastasis are tumor grade and size ≥6 cm. Amputation was not associated with poorer disease-specific survival.

Unusual lipid poor spindle cell lipoma.

Spindle cell lipomas (SCLs) containing minimal fat are rare and can be diagnostically challenging due to their similar radiographic appearance to other benign and malignant tumours. SCLs are benign lipomatous tumours that typically occur in middle aged to elderly men as slow-growing, painless masses in the subcutaneous tissue of the posterior neck, shoulders or back. However, rarely these tumours can arise in unusual locations such as the lower extremities. We present an unusual case of a lipid poor SCL occurring in the lower extremity. Initial clinical and radiographic findings were suspicious for a malignancy. Two core biopsies demonstrated benign fibro collagenous tissue, so a marginal excision was performed. Final histopathological and immunohistochemical stains confirmed the diagnosis of an SCL. Radiologists, pathologists and oncologic surgeons should be aware of this lipomatous tumour's potential to present in unusual locations with minimal fatty components to increase confidence in radiologic-pathological concordance.

Surgical Management of Metastatic Pathologic Subtrochanteric Fractures: Treatment Modalities and Associated Outcomes.

BACKGROUND: Subtrochanteric pathological fractures (PFs) occur in approximately one-third of femur bone metastases. We seek to analyze surgical treatment strategies for subtrochanteric metastatic PFs and their revision rates. METHODS: A systematic review was performed using the PubMed and Ovid databases. Reoperations as a result of complications were analyzed according to initial treatment modality, primary tumor site, and type of revision procedure. RESULTS: We identified a total of 544 patients, 405 with PFs and 139 with impending fractures. The study population's mean age was 65.85 years with a male/female ratio of 0.9. Patients with subtrochanteric PFs who underwent an intramedullary nail (IMN) procedure (75%) presented a noninfectious revision rate of 7.2%. Patients treated with prosthesis reconstruction (21%) presented a noninfectious revision rate of 8.9% for standard endoprostheses and 2.5% for tumoral endoprostheses (p < 0.001). Revision rates because of infection were 2.2% for standard and 7.5% for tumoral endoprostheses. There were no infections within the IMN and plate/screws group (p = 0.407). Breast was the most common primary tumor site (41%) and had the highest revision rate (14.81%). Prosthetic reconstructions were the most common type of revision procedure. CONCLUSION: No consensus exists regarding the optimal surgical approach in patients with subtrochanteric PFs. IMN is a simpler, less invasive procedure, ideal for patients with a shorter survival. Tumoral prostheses may be better suited for patients with longer life expectancies. Treatment should be tailored considering revision rates, patient's life expectancy, and surgeon's expertise. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Benign Bone Lesions Found in Childhood.

Benign bone tumors are a wide variety of usually asymptomatic neoplasms, which in most cases are diagnosed due to secondary causes. As such, their real incidence is unknown. In the majority of cases, plain radiographs are enough for diagnosis; more advanced imaging, such as CT scan or MRI is sometimes performed for equivocal lesions. Treatment approach depends on whether the lesion is symptomatic and the risk of further progression, or development of secondary malignancies. When non expectant management is decided, treatment options include minimally invasive methods and surgery.

Do cancer patients undergoing surgery for a non-neoplastic related fragility hip fracture have worse outcomes? A retrospective study.

INTRODUCTION: An increasing number of patients sustaining a fragility hip fracture (FHF) have either an active diagnosis or a history of cancer. However, little is known about the outcomes of non-malignant related FHF in this group of patients. We aimed to evaluate the mortality and complications rates during hospitalization, as well as at 1-year follow-up within this population. METHODS: A retrospective cohort study of patients 65 years of age and above, who underwent surgery for the treatment of proximal femoral fractures between January 2012 and June 2016 was conducted. Patients diagnosed with malignancies, both solid (Carcinomas) and a hematological neoplasias (Lymphomas, Multiple Myeloma) were included, along with consecutive controls without a diagnosis of cancer in the 5 years prior to the study period. Demographic, clinical and radiographic parameters were recorded and analyzed. RESULTS: Seven hundred and fifty-two patients with FHF were included, of whom 51 had a malignancy diagnosis within the 5-year period preceding the fracture (18% metastatic disease). The mean time from malignancy diagnosis to FHF was 4.3 ± 4.8 years. Time to surgery did not differ between groups, and the vast majority of patients from both groups (over 87%) were operated within the desirable 48 h from admission. Patients with malignancy had a higher probability of being admitted to an internal medicine department both pre and post-surgically (p < 0.001), and were more susceptible to pre-operative anemia (p = 0.034). In-hospital mortality did not differ between groups, yet 1-year mortality was higher for the malignancy group (41.2% vs 19.5%, p < 0.001). At 1-year post-operatively, orthopedic complications were similar between groups. CONCLUSION: Patients with a history of malignancy in the 5-years prior to a non-neoplastic FHF, showed similar mortality and complications rates during admission but increased 1 year mortality rate when compared to patients without cancer undergoing surgical treatment of a non-neoplastic proximal femoral fracture.

Epidemiology and survival factors of appendicular myxofibrosarcoma: a SEER-retrospective study.

Background: The low incidence of myxofibrosarcoma (MFS) makes high power studies difficult to perform. Demographic and prognostic factors for MFS and how they differ from all extremity soft tissue sarcomas (STS) are not well understood. The purpose of this study was to characterize a large cohort of patients with MFS and evaluate epidemiologic and survival factors when compared to all STS. Materials and methods: We performed a retrospective review of the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2015 to identify 1,440 patients diagnosed with MFS and 12,324 with STS. Survival curves were creased using Kaplan-Meier, and Cox regression analyses were performed to identify hazard ratios (HRs). Results: Overall survival was greater for STS than MFS (79% vs. 67%). Patients with MFS had a higher average age at diagnosis than STS (62 vs. 56), and older age was strongly associated with decreased survivorship for MFS (HR = 7.94). A greater proportion of patients under 30 diagnosed with MFS were female when compared to STS (49.6% vs. 45.4%). The incidence of MFS and STS increased over the 15-year period, with MFS increasing at a greater rate than STS (1.25% vs. 2.59%). Survival increased for patients diagnosed after 2008 for both STS (9.4%) and MFS (13.2%). Conclusions: There are differences between patient demographics and survival factors when comparing MFS to all STS. Monitoring changes in demographic and survival trends for rare STS subtypes like MFS is important to improve diagnostic algorithms and treatment options.

Risk Factors and Management of Prosthetic Joint Infections in Megaprostheses-A Review of the Literature.

Prosthetic joint infection (PJI) is the most common mode of failure of megaprostheses, yet the literature on the topic is scarce, and studies report conflicting data regarding the optimal treatment strategy. Patients with megaprostheses PJI are often immunosuppressed, and surgeons must balance the trade-off between treatment efficacy and morbidity associated with the surgery aiming for infection eradication. Our review on megaprostheses PJI focuses on two axes: (1) risk factors and preventative strategies; and (2) surgical strategies to manage this condition. Risk factors were classified as either unmodifiable or modifiable. Attempts to decrease the risk of PJI should target the latter group. Strategies to prevent PJI include the use of silver-coated implants, timely discontinuation of perioperative antibiotic prophylaxis, and adequate soft tissue coverage to diminish the amount of dead space. Regarding surgical treatment, main strategies include debridement, antibiotics, implant retention (DAIR), DAIR with modular component exchange, stem retention (DAIR plus), one-stage, and two-stage revision. Two-stage revision is the "gold standard" for PJI in conventional implants; however, its success hinges on adequate soft tissue coverage and willingness of patients to tolerate a spacer for a minimum of 6 weeks. DAIR plus and one-stage revisions may be appropriate for a select group of patients who cannot endure the morbidity of two surgeries. Moreover, whenever DAIR is considered, exchange of the modular components should be performed (DAIR plus). Due to the low volume of megaprostheses implanted, studies assessing PJI should be conducted in a multi-institutional fashion. This would allow for more meaningful comparison of groups, with sufficient statistical power. Level of evidence: IV.

Treatment and survival outcomes in metastatic Merkel cell carcinoma: Analysis of 2010 patients from the SEER database.

INTRODUCTION: Merkel cell carcinoma (MCC) is an aggressive cutaneous cancer that frequently compromises the lymph nodes (LN) and distal organs. We sought to describe clinical and demographic characteristics of affected patients, analyze risk factors for LN compromise, metastasis, and death, and evaluate their impact on survival. MATERIALS AND METHODS: Patients with MCC were retrieved from the SEER database. Demographic, clinical and treatment data were analyzed. Logistic and Cox proportional hazard regression were used to analyze risk factors. Survival analysis was done with the Kaplan-Meier method. RESULTS: A total of 2010 patients were included, among which 288 (14.33%) had distant metastases at diagnosis. LN involvement occurred in 45.8% and 20.1% of patients with and without distant metastasis, respectively. Males were more likely to present LN compromise (OR = 1.33, p<0.001). Tumors >10 mm showed a significantly higher risk for LN involvement and distant metastasis, with those >20 mm showing the highest risk (OR = 2.76 p<0.001 and OR = 8.88 p<0.001 respectively). Location of the tumor in the trunk was a protective factor for overall death (OR = 0.27), while LN compromise was a risk factor (OR = 3.12). Only history of previous malignancy significantly affected disease-specific death (OR = 0.32, p = 0.01). One-year survival was 79.7% and 38.2% for patients with regional LN disease and distant metastasis, respectively. CONCLUSION: MCC is an aggressive cancer with high rates of LN involvement and distant metastases. Male gender and tumor size were risk factors for regional LN and metastatic disease. Tumor location in the trunk decrease the risk of overall death, while LN involvement increased it.

Management of Long Bones Metastatic Disease: Concepts That We All Know but Not Always Remember.

Bones are the third most common site of metastatic disease. Treatment is rarely curative; rather, it seeks to control disease progression and palliate symptoms. Imaging evaluation of a patient with symptoms of metastatic bone disease should begin with plain X-rays. Further imaging consists of a combination of (PET)-CT scan and bone scintigraphy. We recommend performing a biopsy after imaging workup has been conducted. Metastatic bone disease is managed with a combination of systemic treatment, radiotherapy (RT), and surgery. External beam RT (EBRT) is used for pain control and postoperatively after fracture stabilization. Single-fraction and multiple-fractions schemes are equally effective achieving pain control. Adequate assessment of fracture risk should guide the decision to stabilize an impending fracture. Despite low specificity, plain X-rays are the first tool to determine risk of impending fractures. CT scan offers a higher positive predictive value and can add diagnostic value. Surgical management depends on the patient's characteristics, tumor type, and location of fracture/bone stock. Fixation options include plate and screw fixation, intramedullary (IM) nailing, and endoprostheses. Despite widespread use, the need for prophylactic stabilization of the entire femur should be individually analyzed in each patient due to higher complication rates of long stems.

Squamous Cell Carcinoma Arising from Chronic Osteomyelitis in the Extremities: Treatment Approach and Oncological Outcomes-A Systematic Review of the Literature.

Aims: In chronic osteomyelitis-derived squamous cell carcinoma, what are the demographic and clinical variables, risk factors associated with worse outcomes, and results of treatment modalities used? Methods: A systematic review was performed using PubMed and EMBASE. Articles were evaluated for inclusion and exclusion criteria, and for quality analysis. PRISMA guidelines were applied. Demographic and clinical data and therapeutic approaches were presented narratively and in descriptive statistics registered at PROSPERO. Results: Most patients were male (40/49), trauma was the most common etiology (27/36), and about half of all SCC were in the tibia (25/48). Amputation was the main definitive treatment (42/47). Adjuvant treatments were not analyzed. Well-differentiated SCC accounted for 58.3% (21/36) of all tumors. Bone invasion was described in 82.8% (24/29); recurrence, in 7.7% (3/39); and metastasis, in 7.7% (3/39). Recurrence and metastasis occurred more frequently when bone invasion was present (p = 0.578 and p = 0.646, respectively). SCC with lymph node involvement showed a higher tendency to metastasize (p = 0.377). Compared with limb salvage, amputation was associated with a tendency for less recurrence (p = 0.312) and longer survival (p = 0.219). Conclusions: COM-derived SCC mostly occurs after trauma and is usually located in the tibia. Bone invasion is common, and patients predominantly undergo amputation. This treatment is associated with a trend toward higher survival, compared to limb salvage.

Appendicular dedifferentiated chondrosarcoma: A management and survival study from the SEER database.

Introduction: Dedifferentiated chondrosarcoma (DDC) is an aggressive osseous neoplasm with a dismal prognosis. Treatment commonly involves limb-salvage surgery or amputation. In patients with appendicular DDC, we sought to describe demographic, clinical and treatment characteristics (1), analyze risk factors for metastasis (2) and overall death (3), and assess survival rates by treatment (4). Materials and methods: Two-hundred-and-five patients from the SEER Database were included in our analysis. Demographic, clinical and treatment variables were analyzed. Multivariate regression was performed to identify risk factors. Survival analysis was performed using the Kaplan-Meier method. Results: Fifty-one (24.9 %) of the patients included presented metastasis at diagnosis. The most common locations were the lungs, other sites, and bone. Surgery to the primary site was more common in patients without metastasis (94.2 %) than those with (78.2 %); limb-salvage procedures were more common than amputations. Tumors >8 cm (T2) and those discontinuous (T3) were more likely to present metastasis at diagnosis (OR = 2.54, p = 0.043 and OR = 7.4, p = 0.008, respectively). Female gender was found to be a protective factor for overall death on crude analysis (OR = 0.33, p = 0.019). Metastases to sites other than the lungs (M1b) had the highest risk of overall death (OR = 49, p = 0.01). Combination of surgery and chemotherapy showed a trend towards higher overall survival in non-metastatic patients (p = 0.1069 and p = 0.1703). Conclusions: Appendicular DDC displays a high metastatic rate and low survival rates. The most common procedure is a limb-salvage surgery. Tumor size increases the risk of presenting metastases at diagnosis and female gender is a protective factor against death.