BRAF V600E is associated with higher incidence of second cancers in adults with Langerhans cell histiocytosis.

In this retrospective study, BRAF mutation status did not correlate with disease extent or (event-free) survival in 156 adults with Langerhans cell histiocytosis. BRAFV600E was associated with an increased incidence of second malignancies, often comprising hematological cancers, which may be clonally related.

Evaluation of response to neoadjuvant chemotherapy in osteosarcoma using dynamic contrast-enhanced MRI: development and external validation of a model.

OBJECTIVE: To identify which dynamic contrast-enhanced (DCE-)MRI features best predict histological response to neoadjuvant chemotherapy in patients with an osteosarcoma. METHODS: Patients with osteosarcoma who underwent DCE-MRI before and after neoadjuvant chemotherapy prior to resection were retrospectively included at two different centers. Data from the center with the larger cohort (training cohort) was used to identify which method for region-of-interest selection (whole slab or focal area method) and which change in DCE-MRI features (time to enhancement, wash-in rate, maximum relative enhancement and area under the curve) gave the most accurate prediction of histological response. Models were created using logistic regression and cross-validated. The most accurate model was then externally validated using data from the other center (test cohort). RESULTS: Fifty-five (27 poor response) and 30 (19 poor response) patients were included in training and test cohorts, respectively. Intraclass correlation coefficient of relative DCE-MRI features ranged 0.81-0.97 with the whole slab and 0.57-0.85 with the focal area segmentation method. Poor histological response was best predicted with the whole slab segmentation method using a single feature threshold, relative wash-in rate <2.3. Mean accuracy was 0.85 (95%CI: 0.75-0.95), and area under the receiver operating characteristic curve (AUC-index) was 0.93 (95%CI: 0.86-1.00). In external validation, accuracy and AUC-index were 0.80 and 0.80. CONCLUSION: In this study, a relative wash-in rate of <2.3 determined with the whole slab segmentation method predicted histological response to neoadjuvant chemotherapy in osteosarcoma. Consistent performance was observed in an external test cohort.

A novel colony-stimulating factor 1 (CSF1) translocation involving human endogenous retroviral element in a tenosynovial giant cell tumor.

Tenosynovial giant cell tumors (TSGCTs) are rare tumors arising in tendons or the synoviae of joints and bursae. The localized type is benign while the diffuse type shows expansive growth leading to greater morbidity and is therefore considered locally aggressive. Typical recurrent chromosomal aberrations are found in the majority of TSCGT and the CSF1 gene is frequently involved. In this article, we describe a newly identified gene fusion mediated by an inversion in a case of diffuse TSGCT. Multicolor-fluorescence in situ hybridization (FISH) molecular karyotyping identified a pericentric inversion of chromosome 1 in 7 out of 17 analyzed cells 46,XX,inv(1)(p13.3q24.3) [7]/46,XX [10], and with interphase FISH the involvement the CSF1 locus was detected. After performing transcriptome sequencing analysis for fusion detection, only one out of five fusion gene algorithms detected a fusion involving the CSF1 gene product. The resulting chimera fuses a sequence from a human endogenous retrovirus (HERV) gene to CSF1 Exon 6 on chromosome 1, abrogating the regulatory element of the 3' untranslated region of the CSF1 gene. This new translocation involving Exon 6 of the CSF1 gene fused to 1q24.1, supports the hypothesis that a mutated CSF1 protein is likely to play a vital role in the pathogenesis of TSGCT. The role of the HERV partner identified as a translocation partner, however, remains unclear. Our data add to the complexity of involved translocation partners in TSGCT and point to the potential difficulty of identifying fusion partners in tumor diagnostics using transcriptome sequencing when HERV or other repeat elements are involved.

Impaired social functioning in adolescent and young adult sarcoma survivors: Prevalence and risk factors.

BACKGROUND: Sarcomas account for almost 11% of all cancers in adolescents and young adults (AYAs; 18-39 years). AYAs are increasingly recognized as a distinct oncological age group with its own psychosocial challenges and biological characteristics. Social functioning has been shown to be one of the most severely affected domains of health-related quality of life in AYA cancer survivors. This study aims to identify AYA sarcoma survivors with impaired social functioning (ISF) and determine clinical and psychosocial factors associated with ISF. METHODS: AYAs from the population-based cross-sectional sarcoma survivorship study (SURVSARC) were included (n = 176). ISF was determined according to the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 social functioning scale, and age- and sex-matched norm data were used as reference. RESULTS: The median time since diagnosis was 6.2 years (range, 1.8-11.2). More than one-quarter (28%) of AYA sarcoma survivors experienced ISF. Older age, higher tumor stage, comorbidities, lower experienced social support, uncertainty in relationships, feeling less attractive, sexual inactivity, unemployment, and financial difficulties were associated with ISF. In a multivariable analysis, unemployment (OR, 3.719; 95% CI, 1.261-10.967) and having to make lifestyle changes because of financial problems caused by one's physical condition or medical treatment (OR, 3.394; 95% CI, 1.118-10.300) were associated with ISF; better experienced social support was associated with non-ISF (OR, 0.739; 95% CI, 0.570-0.957). CONCLUSION: More than one-quarter of AYA sarcoma survivors experience ISF long after diagnosis. These results emphasize the importance of follow-up care that is not only disease-oriented but also focuses on the psychological and social domains. PLAIN LANGUAGE SUMMARY: Sarcomas account for almost 11% of all cancers in adolescents and young adults (AYAs; 18-39 years). The AYA group is increasingly recognized as a distinct oncological age group with its own psychosocial challenges and biological characteristics. Social functioning has been shown to be severely affected in AYA cancer survivors. A population-based questionnaire study to identify AYA sarcoma survivors with impaired social functioning (ISF) and determine factors associated with ISF was conducted. More than one-quarter of AYA sarcoma survivors experience ISF long after diagnosis. These results emphasize the importance of follow-up care that is not only disease-orientated but also focuses on the psychological and social domains.

Multimodal management of tenosynovial giant cell tumors (TGCT) in the landscape of new druggable targets.

Tenosynovial giant cell tumor (TGCT) is a rare, benign, locally aggressive synovial based neoplastic process that can result in functional debilitation and end-stage arthrtitis. Although surgical resection is the primary treatment modality, novel systemic therapies are emerging as part of the multimodal armamentarium for patients with unresectable or complex disease burden. This review discusses the pathogenesis of TGCT, potential druggable targets and therapeutic approaches. It also evaluates the safety and efficacy of different systemic therapies.

The treatment of aneurysmal bone cysts.

PURPOSE OF REVIEW: Aneurysmal bone cysts are rare, locally aggressive bone tumors. Optimal treatment of ABCs is still matter of debate as therapies including sclerotherapy, selective arterial embolization and systemic treatment with denosumab are increasingly utilized, in addition to or instead of traditional curettage. The purpose of this review is to discuss current concepts and difficulties in diagnosing and treating primary ABCs, based on latest available literature. RECENT FINDINGS: In diagnostics, multiple new fusion partners of USP-6 have been described on next-generation sequencing specifically for primary ABCs. In a recent systematic review, failure rates of percutaneous injections and surgery were comparable. In a literature review, the use of denosumab seemed effective but resulted in multiple cases of severe hypercalcemia in children. SUMMARY: Accurately diagnosing primary ABC is crucial for treatment decisions. Curettage remains a valid treatment option, especially with adjuvant burring, autogenous bone grafting and phenolization. Percutaneous sclerotherapy represents a solid alternative to surgery, with polidocanol showing good results in larger studies. Systematic therapy with denosumab exhibits favorable results but should be reserved in the pediatric population for unresectable lesions, as it may result in severe hypercalcemia in children. When selecting a treatment option, localization, stability and safety should be considered.

Do's and Don'ts in Primary Aneurysmal Bone Cysts of the Proximal Femur in Children and Adolescents: Retrospective Multicenter EPOS Study of 79 Patients.

BACKGROUND: Aneurysmal bone cysts (ABC) are rare benign cystic bone tumors, generally diagnosed in children and adolescents. Proximal femoral ABCs may require specific treatment strategies because of an increased pathologic fracture risk. As few reports are published on ABCs, specifically for this localization, consensus regarding optimal treatment is lacking. We present a large retrospective study on the treatment of pediatric proximal femoral ABCs. METHODS: All eligible pediatric patients with proximal femoral ABC were included, from 11 tertiary referral centers for musculo-skeletal oncology (2000-2021). Patient demographics, diagnostics, treatments, and complications were evaluated. Index procedures were categorized as percutaneous/open procedures and osteosynthesis alone. Primary outcomes were: time until full weight-bearing and failure-free survival. Failure was defined as open procedure after primary surgery, >3 percutaneous procedures, recurrence, and/or fracture. Risk factors for failure were evaluated. RESULTS: Seventy-nine patients with ABC were included [mean age, 10.2 (±SD4.0) y, n=56 male]. The median follow-up was 5.1 years (interquartile ranges=2.5 to 8.8).Index procedure was percutaneous procedure (n=22), open procedure (n=35), or osteosynthesis alone (n=22). The median time until full weight-bearing was 13 weeks [95% confidence interval (CI)=7.9-18.1] for open procedures, 9 weeks (95% CI=1.4-16.6) for percutaneous, and 6 weeks (95% CI=4.3-7.7) for osteosynthesis alone ( P =0.1). Failure rates were 41%, 43%, and 36%, respectively. Overall, 2 and 5-year failure-free survival was 69.6% (95% CI=59.2-80.0) and 54.5% (95% CI=41.6-67.4), respectively. Risk factors associated with failure were age younger than 10 years [hazard ratios (HR)=2.9, 95% CI=1.4-5.8], cyst volume >55 cm 3 (HR=1.7, 95% CI=0.8-2.5), and fracture at diagnosis (HR=1.4, 95% CI=0.7-3.3). CONCLUSIONS: As both open and percutaneous procedures along with osteosynthesis alone seem viable treatment options in this weight-bearing location, optimal treatment for proximal femoral ABCs remains unclear. The aim of the treatment was to achieve local cyst control while minimizing complications and ensuring that children can continue their normal activities as soon as possible. A personalized balance should be maintained between undertreatment, with potentially higher risks of pathologic fractures, prolonged periods of partial weight-bearing, or recurrences, versus overtreatment with large surgical procedures, and associated risks. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Carbon-fibre plates for traumatic and (impending) pathological fracture fixation: Where do we stand? A systematic review.

BACKGROUND: Carbon-fibre (CF) plates are increasingly used for fracture fixation. This systematic review evaluated complications associated with CF plate fixation. It also compared outcomes of patients treated with CF plates versus metal plates, aiming to determine if CF plates offered comparable results. The study hypothesized that CF plates display similar complication rates and clinical outcomes as metal plates for fracture fixation. METHODS: The study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The following databases were searched from database inception until June 2023: PubMed, MEDLINE, Embase, Web of Science, Cochrane Library, Emcare, Academic Search Premier and Google Scholar. Studies reporting on clinical and radiological outcomes of patients treated with CF plates for traumatic fractures and (impending) pathological fractures were included. Study quality was assessed, and complications were documented as number and percentage per anatomic region. RESULTS: A total of 27 studies of moderate to very low quality of evidence were included. Of these, 22 studies (800 patients, median follow-up 12 months) focused on traumatic fractures, and 5 studies (102 patients, median follow-up 12 months) on (impending) pathological fractures. A total of 11 studies (497 patients, median follow-up 16 months) compared CF plates with metal plates. Regarding traumatic fractures, the following complications were mostly reported: soft tissue complications (52 out of 391; 13%) for the humerus, structural complications (6 out of 291; 2%) for the distal radius, nonunion and structural complication (1 out of 34; 3%) for the femur, and infection (4 out of 104; 4%) for the ankle. For (impending) pathological fractures, the most frequently reported complications were infections (2 out of 14; 14%) for the humerus and structural complication (6 out of 86; 7%) for the femur/tibia. Comparative studies reported mixed results, although the majority (7 out of 11; 64%) reported no significant differences in clinical or radiological outcomes between patients treated with CF or metal plates. CONCLUSION: This systematic review did not reveal a concerning number of complications related to CF plate fixation. Comparative studies showed no significant differences between CF plates and metal plates for traumatic fracture fixation. Therefore, CF plates appear to be a viable alternative to metal plates. However, high-quality randomized controlled trials (RCTs) with long-term follow-up are strongly recommended to provide additional evidence supporting the use of CF plates. LEVEL OF EVIDENCE: III, systematic review.

Updated concepts in treatment of giant cell tumor of bone.

PURPOSE OF REVIEW: Giant cell tumors of bone (GCTB) are intermediate, locally aggressive primary bone tumors. For conventional GCTB, surgery remains treatment of choice. For advanced GCTB, a more important role came into play for systemic therapy including denosumab and bisphosphonates over the last decade. RECENT FINDINGS: In diagnostics, focus has been on H3F3A (G34) driver mutations present in GCTB. The most frequent mutation (G34W) can be detected using immunohistochemistry and is highly specific in differentiating GCTB from other giant cell containing tumors. PD-L1 expression can be used as biological marker to predict higher recurrence risks in GCTB patients.The use of bisphosphonate-loaded bone cement is under investigation in a randomized controlled trial. A new technique consisting of percutaneous microwave ablation and bisphosphonate-loaded polymethylmethacrylate cementoplasty was proposed for unresectable (pelvic) GCTB.Increased experience with use of denosumab raised concern on elevated recurrence rates. However, conclusions of meta-analyses should be interpreted with risk of indication bias in mind. Several small studies are published with short-course denosumab (varying from 3 to 6 doses). One small trial directly compared denosumab and zoledronic acid, with no statistical differences in radiological and clinical outcome, and nonsignificantly higher recurrence rate after denosumab. As bisphosphonates directly target neoplastic stromal cells in GCTB, larger directly comparative trials are still warranted. SUMMARY: Neoadjuvant denosumab is highly effective for advanced GCTB, and a short-course is advised to facilitate surgery, whereas increased recurrence rates remain of concern. Randomized controlled trials are conducted on bisphosphonate-loaded bone cement and on optimal dose and duration of neoadjuvant denosumab. PD-L1 could be a potential new therapy target in GCTB.

Surgical management of 144 diffuse-type TGCT patients in a single institution: A 20-year cohort study.

BACKGROUND AND OBJECTIVES: Surgery is the mainstay of treatment for tenosynovial giant cell tumors (TGCTs). However, achieving a cure through surgery alone remains challenging, especially for the diffuse-type (D-TGCT). METHODS: Our goal was to describe the surgical management of patients with D-TGCT related to large joints, treated between 2000 and 2020. We analyzed the effect of (in)complete resections and the presence of postoperative tumor (POT) on magnetic resonance imaging (MRI) on radiological and clinical outcomes. RESULTS: A total of 144 patients underwent open surgery for D-TGCT, of which 58 (40%) had treatment before. The median follow-up was 65 months. One hundred twenty-five patients underwent isolated open surgeries, in which 25 (20%) patients' D-TGCT was intentionally removed incompletely. POT presence on the first postoperative MRI was observed in 64%. Both incomplete resections and POT presence were associated with higher rates of radiological progression (73% vs. 44%; Kaplan-Meier [KM] analysis p = 0.021) and 59% versus 7%; KM analysis p < 0.001), respectively. Furthermore, patients with POT presence clinically worsened more often than patients without having POT (49% vs. 24%; KM analysis p = 0.003). CONCLUSIONS: D-TGCT is often resected incompletely and tumor presence is commonly observed on the first postoperative MRI, resulting in worse radiological and clinical outcomes. Therefore, surgeons should try to remove D-TGCT in toto and consider other multimodal therapeutic strategies.

Intraosseous hibernoma of the appendicular skeleton.

Hibernomas are rare lipomatous tumors composed of brown adipocytes. The relative paucity of reported cases involving the bones accounts for the poor understanding of this entity, which is known to affect almost exclusively the axial skeleton. We present a case of intraosseous hibernoma of the humerus, which was found incidentally in a 52-year-old woman and initially misinterpreted as a cartilaginous tumor on magnetic resonance imaging (MRI). The lesion was unchanged in size and morphology at short interval follow-up but increased in size during follow-up over 6 years with an 11 mm increase in the largest diameter. Given the patient's concerns and lesion growth, curettage was performed. Pathology analysis revealed brown fat in keeping with the diagnosis of intraosseous hibernoma. Radiological and pathological findings and pitfalls are herein highlighted to enforce knowledge on this lesion rarely affecting the long bones. Radiologists should think of intraosseous hibernoma if they come across a sclerotic lesion on X-ray or computed tomography, which contains macroscopic fat and shows enhancement on contrast-enhanced MRI. In addition, an intraosseous hibernoma may be picked up incidentally on positron emission tomography-computed tomography due to high fluorodeoxyglucose avidity.

Long-term outcomes of pexidartinib in tenosynovial giant cell tumors.

BACKGROUND: The objective of this study was to report on the long-term effects of pexidartinib on tenosynovial giant cell tumor (TGCT). METHODS: This was a pooled analysis encompassing 3 pexidartinib-treated TGCT cohorts: 1) a phase 1 extension study (NCT01004861; 1000 mg/d; n = 39), 2) ENLIVEN patients randomized to pexidartinib (1000 mg/d for 2 weeks and then 800 mg/d; n = 61), and 3) ENLIVEN crossover patients (NCT02371369; 800 mg/d; n = 30). Eligible patients were 18 years old or older and had a histologically confirmed TGCT that was unresectable and symptomatic. Efficacy endpoints included the best overall response (complete or partial response) and the duration of response (DOR) by the Response Evaluation Criteria in Solid Tumors (RECIST) and the tumor volume score (TVS). The safety assessment included the frequency of treatment-emergent adverse events (TEAEs) and hepatic laboratory abnormalities (aminotransferase elevations and mixed/cholestatic hepatotoxicity). The data cutoff was May 31, 2019. RESULTS: One hundred thirty patients with TGCT received pexidartinib (median treatment duration, 19 months; range, 1 to 76+ months); 54 (42%) remained on treatment at the end of the analysis (26 months after initial data cut of March 2017). The RECIST overall response rate (ORR) was 60%; the TVS ORR was 65%. The median times to response were 3.4 (RECIST) and 2.8 months (TVS), with 48 of the responding patients (62%) achieving a RECIST partial response by 6 months and with 72 (92%) doing so by 18 months. The median DOR was reached for TVS (46.8 months). Reported TEAEs were mostly low-grade, with hair color changes being most frequent (75%). Most liver abnormalities (92%) were aminotransferase elevations; 4 patients (3%) experienced mixed/cholestatic hepatotoxicity (all within the first 2 months of treatment), which was reversible in all cases (recovery spanned 1-7 months). CONCLUSIONS: This study demonstrates the prolonged efficacy and tolerability of long-term pexidartinib treatment for TGCT.

Management of Soft Tissue Sarcomas in Extremities: Variation in Treatment Recommendations and Surveillance According to Specialty and Continent.

BACKGROUND: This study aimed to provide an insight into clinical decision-making and surveillance strategy of sarcoma specialists for patients with primary soft tissue sarcoma of the extremities (eSTS). The secondary aim was to quantify the role of patient- and tumor-specific factors in the perioperative management. METHODS: Members of sarcoma societies were sent a Web-based 21-item survey about eSTS management. The survey concerned only primary resectable high-grade eSTS in adults. RESULTS: The study enrolled 396 respondents. The majority of the surgical specialists thought the evidence for perioperative chemotherapy (CTX) for high-grade eSTS was insufficient. Radiotherapy (RTX) was less frequently offered in Asia than in North America and Europe. The specialties and continents also differed regarding the importance of patient and tumor characteristics influencing RTX and CTX recommendation. For surveillance after initial treatment outpatient visits, chest computed tomography (CT) scans, and magnetic resonance images of the extremity were the methods primarily used. The specialists in North America preferred chest CT scan over chest x-ray, whereas those in Asia and Europe had no clear preference. DISCUSSION: Specialty and continent are important factors contributing to the variation in clinical practice, treatment recommendations, and surveillance of patients with primary resectable high-grade eSTS.

External validation and adaptation of a dynamic prediction model for patients with high-grade extremity soft tissue sarcoma.

BACKGROUND AND OBJECTIVES: A dynamic prediction model for patients with soft tissue sarcoma of the extremities was previously developed to predict updated overall survival probabilities throughout patient follow-up. This study updates and externally validates the dynamic model. METHODS: Data from 3826 patients with high-grade extremity soft tissue sarcoma, treated surgically with curative intent were used to update the dynamic PERsonalised SARcoma Care (PERSARC) model. Patients were added to the model development cohort and grade was included in the model. External validation was performed with data from 1111 patients treated at a single tertiary center. RESULTS: Calibration plots show good model calibration. Dynamic C-indices suggest that the model can discriminate between high- and low-risk patients. The dynamic C-indices at 0, 1, 2, 3, 4, and 5 years after surgery were equal to 0.697, 0.790, 0.822, 0.818, 0.812, and 0.827, respectively. CONCLUSION: Results from the external validation show that the dynamic PERSARC model is reliable in predicting the probability of surviving an additional 5 years from a specific prediction time point during follow-up. The model combines patient-, treatment-specific and time-dependent variables such as local recurrence and distant metastasis to provide accurate survival predictions throughout follow-up and is available through the PERSARC app.

Efficacy of Sclerotherapy With Polidocanol (Ethoxysclerol) in Primary Aneurysmal Bone Cysts in Children and Adolescents.

BACKGROUND: Aneurysmal bone cysts (ABC) are rare benign osseous lesions that can be locally aggressive. Traditionally, curettage with or without bone grafting is the treatment of choice. Recent data suggest that percutaneous sclerotherapy is a safe alternative to surgery. We present our experience with percutaneous sclerotherapy. Primary study aims were success rate, risk factors for treatment failure, and complications. METHODS: In this single-center retrospective study (January 2003 to June 2019), 70 patients were treated with percutaneous sclerotherapy for primary ABC at various skeletal sites. Median age was 11 years (range: 3 to 17 y). Median follow-up was 40 months (range 18 to 144 mo). Clinical and radiologic assessments were performed until cyst healing. RESULTS: Successful healing was seen in 58 of 70 patients (83%) after 1 or more injections with polidocanol. In 12 patients (17%), definitive curettage was performed after previous sclerotherapy, which was considered failure of primary sclerotherapy treatment. Trends toward increased risk for >3 treatments or treatment failure included age younger than 5, epiphyseal plate involvement, and lower leg lesions. The only complication was anaphylaxis in 1 patient shortly after injection of polidocanol/contrast agent and ropivacaine, with full recovery after short resuscitation. CONCLUSIONS: Our results show that percutaneous sclerotherapy with polidocanol has high efficacy in the treatment of primary ABC, with a low complication rate. Our only complication may have been an immediate allergic reaction to polidocanol/contrast agent or ropivacaine. Trends toward increased risk for treatment failure were age younger than 5, epiphyseal plate involvement, and lower leg lesions. LEVEL OF EVIDENCE: Level IV-therapeutic study.

Molecular signatures of tumor progression in myxoid liposarcoma identified by N-glycan mass spectrometry imaging.

Myxoid liposarcoma (MLS) is the second most common subtype of liposarcoma, accounting for ~6% of all sarcomas. MLS is characterized by a pathognomonic FUS-DDIT3, or rarely EWSR1-DDIT3, gene fusion. The presence of ≥5% hypercellular round cell areas is associated with a worse prognosis for the patient and is considered high grade. The prognostic significance of areas with moderately increased cellularity (intermediate) is currently unknown. Here we have applied matrix-assisted laser desorption/ionization mass spectrometry imaging to analyze the spatial distribution of N-linked glycans on an MLS microarray in order to identify molecular markers for tumor progression. Comparison of the N-glycan profiles revealed that increased relative abundances of high-mannose type glycans were associated with tumor progression. Concomitantly, an increase of the average number of mannoses on high-mannose glycans was observed. Although overall levels of complex-type glycans decreased, an increase of tri- and tetra-antennary N-glycans was observed with morphological tumor progression and increased tumor histological grade. The high abundance of tri-antennary N-glycan species was also associated with poor disease-specific survival. These findings mirror recent observations in colorectal cancer, breast cancer, ovarian cancer, and cholangiocarcinoma, and are in line with a general role of high-mannose glycans and higher-antennary complex-type glycans in cancer progression.

Patient and diagnostic intervals of survivors of sarcoma: Results from the SURVSARC study.

BACKGROUND: Patients diagnosed with sarcoma are hypothesized to experience a prolonged route to a cancer diagnosis. This route, the total interval, can be divided into a patient interval (the time from the appearance of symptoms to physician consultation) and diagnostic interval (time from the first consultation to diagnosis). In the current study, the authors investigated these intervals among survivors of sarcoma and identified factors associated with prolonged intervals. METHODS: A cross-sectional study was conducted among adult patients with sarcoma 2 to 10 years after diagnosis. Patients completed a questionnaire regarding their total interval, which was linked to clinical data from the Netherlands Cancer Registry. Descriptive statistics were used to describe intervals. Based on Dutch clinical guidelines, a diagnostic interval ≥1 month was considered to be prolonged and an interval ≥3 months was considered as very long. Multivariable regression analyses investigated associations between patient and tumor characteristics and interval length. RESULTS: A total of 1099 participants were included (response rate, 58%); approximately 60% reported a patient interval ≥1 month and 36% reported a patient interval ≥3 months. Risk factors for a very long patient interval were sarcoma of the skin or pelvis, liposarcoma, or rhabdomyosarcoma. Stage III disease was associated with a shorter patient interval. The diagnostic interval length was ≥1 month in 55% of patients and ≥3 months in 28% of patients. Risk factors for a very long diagnostic interval were female sex, age <70 years, or having a synovial sarcoma or chordoma. CONCLUSIONS: The patient and diagnostic interval lengths were prolonged in a substantial percentage of this sarcoma survivorship population. Factors found to be associated with the length of the patient interval or the diagnostic interval differed. Creating awareness among (especially young) patients to consult a physician and awareness among physicians to consider a sarcoma diagnosis will contribute to optimization of the total interval.

Extrameningeal solitary fibrous tumors-surgery alone or surgery plus perioperative radiotherapy: A retrospective study from the global solitary fibrous tumor initiative in collaboration with the Sarcoma Patients EuroNet.

BACKGROUND: Solitary fibrous tumor (SFT) is a rare mesenchymal malignancy. Although surgery is potentially curative, the local relapse risk is high after marginal resections. Given the lack of prospective clinical trial data, the objective of the current study was to better define the role of perioperative radiotherapy (RT) in various SFT presentations by location. METHODS: This was retrospective study performed across 7 sarcoma centers. Clinical information was retrieved from all adult patients with extrameningeal, primary, localized SFT who were treated between 1990 and 2018 with surgery alone (S) compared with those who also received perioperative RT (S+RT). Differences in treatment characteristics between subgroups were tested using analysis of variance statistics and propensity score matching. Local control and overall survival rates were calculated from the start of treatment until progression or death from any cause. RESULTS: Of all 549 patients, 428 (78%) underwent S, and 121 (22%) underwent S+RT. The median follow-up was 52 months. After correction for mitotic count and surgical margins, S+RT was significantly associated with a lower risk of local progression (hazard ratio, 0.19: P = .029), an observation further confirmed by propensity score matching (P = .012); however, this association did not translate into an overall survival benefit. CONCLUSIONS: The results from this retrospective study investigating perioperative RT in patients with primary extrameningeal SFT suggest that combining RT with surgery in the management of this patient population is significantly associated with a reduced risk of local failures, especially in patients who have less favorable resection margins and in those who have tumors with a high mitotic count.

Single-Center Experience with Ifosfamide Monotherapy as Second-Line Treatment of Recurrent/Metastatic Osteosarcoma.

BACKGROUND: The effectiveness of second-line palliative chemotherapy in patients with recurrent/metastatic osteosarcoma is not well defined. Several small studies (6-19 patients) have reported on ifosfamide as second-line treatment. In this study we report our single-center experience with second-line ifosfamide monotherapy in patients treated for recurrent/metastatic osteosarcoma. METHODS: A chart review was conducted of all patients with osteosarcoma treated with ifosfamide from 1978 until 2017. Until 1997 a 5 g/m2 regimen was used, and from 1997 onwards a 9 g/m2 regimen was used. Overall survival (OS) from start of ifosfamide was the primary endpoint. Progression-free survival (PFS) from start of treatment was also studied. To assess difference in survival between groups the log rank test was applied. To investigate the effect of ifosfamide dose and World Health Organization performance status (PS) a Cox proportional hazard regression model was estimated. RESULTS: Sixty-two patients were selected with recurrent/metastatic osteosarcoma treated with second-line ifosfamide monotherapy (dose of 5 g/m2 , n = 26; 9 g/m2 , n = 36). OS was significantly better in univariate analysis for 9 g/m2 compared with 5 g/m2 (10.9 months [95% confidence interval (CI), 9.3-12.6] vs. 6.7 months [95% CI, 5.9-7.6], respectively) and for PS (median OS PS 0, 13.0 months [95% CI, 2.3-23.8]; PS 1, 8.2 months [95% CI, 5.4-11.1]; PS ≥2, 6.2 months [95% CI, 2.2-10.3]; and unknown PS, 5.4 months [95% CI, 2.2-8.5]). In multivariate analysis only PS showed a significant difference. No difference in PFS was found between 5 and 9 g/m2 ifosfamide treatment or PS. CONCLUSION: This study suggests that ifosfamide is an effective second-line treatment for patients with recurrent/metastatic osteosarcoma. IMPLICATIONS FOR PRACTICE: Ifosfamide monotherapy is commonly used as second-line treatment in osteosarcoma, although large series to support this are lacking. This retrospective study reports overall and progression-free survival for regimens with 5 g/m2 and with 9 g/m2 . This study was unable to show a significant difference in survival between 5 and 9 g/m2 but showed an important impact of World Health Organization performance status on overall survival. This study sets a standard and reference for comparison with the multiple phase II studies under development.

Can we use MRI to detect clinically silent recurrent soft-tissue sarcoma?

PURPOSE: The impact of MRI on early detection of local recurrence (LR) in high-grade soft-tissue sarcomas (STS) is unsubstantiated. To identify the contribution of MRI criteria including dynamic contrast-enhanced (DCE) MRI and knowledge of surgical margins that can be used in detecting recurrence prior to obvious proven presence of LR in soft-tissue sarcomas. The secondary aim was to determine causes for misdiagnosing LR. METHODS: MRI of 23 patients (12 men; mean age, 59.7 years ± 16.5 years) with LR of STS and that of 22 age- and histology-matched controls with STS but without LR were retrospectively analyzed by two musculoskeletal radiologists. Preoperative MRI characteristics (conventional and DCE) were compared to those of MRIs made after treatment, but before LR was proven. Likelihood of recurrence was rated on a 5-point Likert scale for morphological and dynamic assessment separately, before and after adding knowledge of surgical margins. Descriptive statistics and receiver operating characteristic analysis were performed. RESULTS: Differentiation of LR from post-therapeutic changes was the highest combining result of conventional MRI, DCE-MRI, and knowledge of surgical margins (area under the curve (AUC) 0.779), followed by DCE-MRI (AUC 0.706) and conventional MRI (AUC 0.648). Suboptimal MRI technique and overcalling post-therapeutic changes in microscopic positive margins were the main reasons for false negative and false positive results, respectively. CONCLUSION: MRI including DCE improves the detection of recurrent, clinically silent soft-tissue sarcoma when combined with knowledge of achieved surgical margins. LR may be missed on inadequate MRI protocols. KEY POINTS: • Dynamic contrast-enhanced MRI is useful in the differentiation of recurrent soft-tissue sarcoma and post-therapeutic fibrosis. • Knowledge of surgical margins substantially increases the value of MRI in detecting recurrent soft-tissue sarcoma. • MR with all three image orientations, covering the entire part of the extremity in at least one sequence and comparison to initial tumor characteristics and location, is beneficial.