ACR Appropriateness Criteria Follow-Up of Malignant or Aggressive Musculoskeletal Tumors

Soft tissue tumor imaging in adults: European Society of Musculoskeletal Radiology-Guidelines 2024: imaging immediately after neoadjuvant therapy in soft tissue sarcoma, soft tissue tumor surveillance, and the role of interventional radiology

OBJECTIVES

An update of the first European Society of Musculoskeletal Radiology (ESSR) consensus on soft tissue tumor imaging in 2015 became necessary due to technical advancements, further insights into specific entities, and the revised WHO classification (2020) and AJCC staging system (2017). The third part of the revised guidelines covers algorithms and techniques beyond initial imaging: (1) Imaging after neoadjuvant therapy in soft tissue sarcoma, (2) sarcoma surveillance, and (3) special aspects, including surveillance of non-malignant entities and the role of interventional radiology.

MATERIALS AND METHODS

A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements that had undergone interdisciplinary revision were scored online by level of agreement (0 to 10) during two iterative rounds that could result in either 'group consensus,' 'group agreement,' or 'lack of agreement.'

RESULTS

The three sections contain 47 statements with comments. Group consensus was reached in 91.5%, group agreement in 6.4%, lack of agreement in 2.1%. In sarcoma, imaging immediately after neoadjuvant therapy is pivotal for determining the therapy effects and for resection-planning; surveillance should include imaging at fixed grade- and type-dependent intervals. In general, MRI is the method of choice for loco-regional surveillance of soft tissue sarcomas, and chest CT to assess metastatic disease. Interventional radiology has a role, especially in oligometastatic disease, palliative tumor control and local recurrences.

CONCLUSION

Strategies for standardized soft tissue tumor imaging regarding therapy control, surveillance, and useful interventional procedures are provided.

KEY POINTS

Question An ESSR consensus update on soft tissue tumor imaging regarding surveillance became necessary due to technical advancements, further entity-specific insights, and revised WHO- and AJCC-classifications. Findings Imaging immediately after neoadjuvant therapy in soft tissue sarcoma is pivotal. Post-therapeutic surveillance should include imaging at regular intervals, stratified for tumor grade and type. Clinical relevance The updated ESSR soft tissue tumor imaging guidelines aim to provide best practice expert consensus for standardized imaging, to support radiologists in their decision-making, and to improve examination comparability, both in individual patients and in future studies on individualized strategies.

Prognostic significance of lymph node metastasis of soft tissue sarcoma of the extremities. National cancer institute experience

BACKGROUND AND OBJECTIVE

Lymph node metastasis (LNM) in soft tissue sarcoma (STS) of the extremities is relatively rare. We aimed to evaluate the prognosis and the survival of patients with LNM and correlate them to the pattern of metastasis.

METHODS

A retrospective study of patients diagnosed with STS of the extremities from 2015 to 2019.

RESULTS

111/1506 patients (7.4%) had LNM. Nodal metastasis was correlated significantly with old age, advanced tumor stages, high-grade tumors, presence of Lymphovascular invasion (LVI), and resection margins <  = 2 cm. Metachronous LNM was documented in 96 patients (86.5%) and synchronous LNM in 15 patients (13.5%). The 6-year overall survival (OS) was 36.3% for those with LNM and 52.9% for those without LNM. The 6-year disease-free survival (DFS) was 5.7% for those with LNM and 32.6% for those without LNM. Metachronus pattern of LNM showed a significantly poorer outcome regarding 6-year OS and DFS than the synchronous pattern.

CONCLUSIONS

LNM significantly negatively predicts OS and DFS in the extremities' STS. In particular, the metachronous pattern of LNM indicates a grave prognosis as these patients are supposed to harbor an occult LNM at presentation and were not subjected to lymphadenectomy at their initial primary treatment surgery. Therefore, seeking a valid noninvasive diagnostic tool such as sentinel lymph node biopsy to detect nodal metastasis is necessary.

Postoperative Imaging of Bone and Soft Tissue Tumors in the Extremity: A Comprehensive Review

Postoperative imaging of musculoskeletal tumors poses a significant diagnostic challenge for radiologists. The complexity arises from the need to differentiate between expected postoperative changes, potential complications, and local recurrence. The choice of imaging modality depends on the type of primary tumor. Standard radiological modalities such as radiography, computed tomography (CT), and magnetic resonance imaging (MRI) are widely utilized. Radiography and CT are especially valuable for assessing primary bone tumors, as they provide detailed views of bone structures and alignment, as well as revealing postoperative complications. MRIs are particularly effective for evaluating soft tissue tumors and identifying local recurrences due to its superior soft tissue contrast. The advanced imaging techniques, such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, have significantly improved diagnostic accuracy in detecting tumor recurrence. An in-depth understanding of surgery-specific imaging findings, as well as the ability to detect recurrent disease, is crucial for early diagnosis of complications and improved patient outcomes. Familiarity with normal postoperative changes helps radiologists distinguish them from abnormal findings indicative of complications or tumor recurrence. This review article aims to outline the surgical options for musculoskeletal tumors, detail the various imaging techniques used in postoperative surveillance, and discuss the potential complications. By understanding the role of different imaging modalities and their applications associated with various surgical procedures, clinicians and radiologists can provide accurate and timely diagnoses.

Failure Modes in Orthopedic Oncologic Reconstructive Surgery: A Review of Imaging Findings and Failure Rates

Limb salvage surgeries utilizing endoprostheses and allografts are performed for a variety of oncologic conditions. These reconstructions can fail and require revision for many reasons, which are outlined and classified into mechanical failures (soft tissue failures, aseptic loosening, structural failure), non-mechanical failures (infection, tumor progression), and pediatric failures (physeal arrest, growth dysplasia). Distinct radiologic and clinical findings define specific failure subtypes but are sparsely illustrated in the radiology literature. Specifically, an understanding of the organizational structure of the failure modes can direct radiologists' search for post-reconstruction complications, enhance an appreciation of their prognostic significance, and facilitate research by standardizing the language and conceptual framework around outcomes. The purpose of this review is to highlight the key radiologic findings and imaging studies of each failure mode in orthopedic oncologic reconstructive surgery in the context of risk factors, failure rates, prognosis and survival statistics, and clinical decision-making regarding chemotherapy, radiation, and revision surgery.

Multiple Bone Involvement in Low-grade Myofibroblastic Sarcoma Demonstrated on 18F-FDG PET/CT

A 68-year-old woman with low back pain for 2 months was admitted. T2-weighted fat-saturated imaging revealed hyperintense lesions in multiple lumbar regions, suggesting the possibility of bone metastases. Multiple osteolytic and mixed osteolytic-osteoblastic lesions with significant 18F-fluorodeoxyglucose (18F-FDG) uptake, as well as multiple osteoblastic lesions with mild 18F-FDG uptake, were observed on subsequent 18F-FDG positron emission tomography/computed tomography without an identifiable primary lesion. This patient was pathologically diagnosed with low-grade myofibroblastic sarcoma (LGMS) after biopsy and surgery. Although multiple bone involvement in LGMS is extremely rare, this case suggests that it should be considered in the differential diagnosis of multiple bone metastases.

Role of magnetic resonance imaging in the prediction of histological grade in soft tissue sarcomas

BACKGROUND

Soft tissue sarcomas are rare malignant tumors with significant heterogeneity. The importance of classifying histological grades is fundamental to defining the treatment approach.

OBJECTIVE

To evaluate magnetic resonance imaging (MRI) in predicting the histological grade of soft tissue sarcomas.

METHODS

A retrospective observational study included patients over 18 years undergoing MRI and primary tumor surgery at AC Camargo Cancer Center from January 2015 to June 2022. Two radiologists evaluated MRI criteria (size, margin definition, heterogeneity of the T2 signal, high-intensity peritumoral signal on T2, and postperitumoral contrast), and a grading prediction score was calculated. χ2 and logistic regression analyses were conducted.

RESULTS

Sixty-eight patients were included (38 men; median: 48 years). Moreover, 52 high-grade and 16 low-grade tumors were observed. The MRI criteria associated with histological grade were peritumoral high-intensity T2-weighted signals (p < 0.001) and peritumoral postcontrast enhancement (p = 0.006). Logistic regression confirmed their significance (odds ratio [OR]: 11.8 and 8.8, respectively). Each score point increment doubled the chance of high-grade tumors (OR: 2.0; p = 0.014).

CONCLUSION

MRI effectively predicts histological grades of soft tissue sarcomas. Peritumoral high-intensity T2-weighted signals and peritumoral postcontrast enhancement are valuable indicators of high-grade tumors. This highlights MRI's importance in treatment decision-making for sarcoma patients.

Incidence of avascular necrosis of native femur following hip transposition surgery for periacetabular malignancies: a single-centre experience

BACKGROUND

Hip transposition surgery after surgical resection of large pelvic tumours is a well-established alternate to endoprosthetic reconstruction. The major goals of surgery are to ensure adequate resection margins with limb salvation, albeit with acceptable levels of morbidity. While surveillance is aimed at diagnosing local recurrence or distant metastasis primarily, other complications may occasionally be seen.The aim of this study was to assess incidence of avascular necrosis (AVN) in the preserved native femoral heads after hip transposition surgery for periacetabular malignancies, also known as hanging hip surgery.

PATIENTS AND METHODS

Patient records and follow-up imaging of 22 patients who had undergone hanging hip surgery from 1999 to 2020 were retrospectively analysed to assess for any probable causes of AVN.

RESULTS

Of the 22 patients, 5 (22.7%) had developed AVN on follow-up with a mean time of onset of about 10.5 months from surgery (5 months-2 years). A review of the patient demographics, surgical notes, preoperative management did not offer any clues as to the cause of AVN in these patients. Osteopenia was the most common radiological finding (59%) in most patients, but this also did not herald AVN onset.

CONCLUSIONS

The theory that loss of major vascular supply to the femoral head from capsular disruption during hip transposition surgery would lead to AVN in most patients did not hold true as AVN occurred in a small number of patients.

The role of imaging in extremity sarcoma surgery

The surgical management of extremity bone and soft tissue sarcomas has evolved significantly over the last 50 years. The introduction and refinement of high-resolution cross-sectional imaging has allowed accurate assessment of anatomy and tumor extent, and in the current era more than 90% of patients can successfully undergo limb-salvage surgery. Advances in imaging have also revolutionized the clinician's ability to assess treatment response, detect metastatic disease, and perform intraoperative surgical navigation. This review summarizes the broad and essential role radiology plays in caring for sarcoma patients from diagnosis to post-treatment surveillance. Present evidence-based imaging paradigms are highlighted along with key future directions.

Beyond Clinical Examination: Utilizing MRI Surveillance to Detect Recurrence of Soft Tissue Sarcomas and Differentiate from Posttherapeutic Changes

BACKGROUND

Early detection of soft tissue sarcoma (STS) recurrence is essential; however, the role and timeline of Magnetic resonance imaging (MRI) surveillance are still under debate. The aim of this study was to determine whether local recurrence (LR) could be identified via clinical examination alone and to assess the MRI morphology of primary STS and LR.

METHODS

This retrospective study included all patients with STS recurrence after surveillance for at least five years from the tumor database of the Medical University of Vienna from 2000 until December 2023. The characteristics of primary STS and LR and the time interval to recurrence and clinical detectability were assessed. The MRIs of LR and posttherapeutic changes (PTC) were compared with the initial MRIs.

RESULTS

A total of 57 patients (60% male; mean age 58.5 ± 18.0 years) with STS and histologically confirmed LR were included. The mean time interval to LR was 2.3 ± 1.8 years (range 108 to 3037 days). The clinically detectable recurrences were significantly larger than the inapparent ones (71.9 cm3 vs. 7.0 cm3; p < 0.01). The MRI morphology of all LRs (26/26) closely resembled the initial STS. For comparison, nine patients were included with clinically suspected LRs, which were histologically proven to be PTC. None of these resembled the primary STS.

CONCLUSION

Based on clinical symptoms alone, especially small and early recurrences can be missed, which supports the importance of MRI surveillance.

A bibliometric analysis based on hotspots and frontier trends of positron emission tomography/computed tomography utility in bone and soft tissue sarcoma

Purpose

This study aimed to analyze articles on the diagnosis and treatment of bone and soft tissue sarcoma using positron emission tomography (PET)/computed tomography (CT) published in the last 13 years. The objective was to conduct a bibliometric analysis and identify the research hotspots and emerging trends.

Methods

Web of Science was used to search for articles on PET/CT diagnosis and treatment of bone and soft tissue sarcoma published from January 2010 to June 2023. CiteSpace was utilized to import data for bibliometric analysis.

Results

In total, 425 relevant publications were identified. Publications have maintained a relatively stable growth rate for the past 13 years. The USA has the highest number of published articles (139) and the highest centrality (0.35). The UDICE-French Research Universities group is the most influential institution. BYUN BH is a prominent contributor to this field. The Journal of Clinical Oncology has the highest impact factor in the field.

Conclusion

The clinical application of PET/CT is currently a research hotspot. Upcoming areas of study concentrate on the merging of PET/CT with advanced machine learning and/or alternative imaging methods, novel imaging substances, and the fusion of diagnosis and therapy. The use of PET/CT has progressively become a crucial element in the identification and management of sarcomas. To confirm its efficacy, there is a need for extensive, multicenter, prospective studies.

Molecular Imaging in Soft-tissue Sarcoma: Evolving Role of FDG PET

Soft tissue sarcomas are a rare and heterogenous group of tumors that account for 2% of all cancer-related deaths. Molecular imaging with FDG PET can offer valuable metabolic information to help inform clinical management of soft tissue sarcomas that is unique and complementary to conventional diagnostic imaging techniques. FDG PET imaging often correlates with tumor grade, can help guide biopsy, and frequently detects additional sites of disease compared to conventional imaging in patients being considered for definitive or salvage therapy. Traditional size-based evaluation of treatment response is often inadequate in soft tissue sarcoma and changes in metabolic activity can add significant value to interim and end of treatment imaging for high-grade sarcomas. FDG PET can be used for detection of recurrence or malignant transformation and thus play a vital role in surveillance. This article reviews the evolving role of FDG PET in initial diagnosis, staging, treatment response assessment, and restaging. Further studies on the use of FDG PET in soft sarcoma are needed, particularly for rare histopathologic subtypes.

Coefficient of variation of T2-weighted MRI may predict the prognosis of malignant peripheral nerve sheath tumor

BACKGROUND

We investigated whether non-enhancement MRI features, including measurement of the heterogeneity of the tumor with MR T2 imaging by calculating coefficient of variation (CV) values, were associated with the prognosis of non-metastatic malignant peripheral nerve sheath tumors (MPNST).

METHODS

This retrospective study included 42 patients with MPNST who had undergone surgical resection (mean age, 50 years ± 21; 20 male participants). Non-enhancement MR images were evaluated for signal intensity heterogeneity on T1- and T2-weighted imaging, tumor margin definition on T1- and T2-weighted imaging, peritumoral edema on T2-weight imaging, and CV. We measured the signal intensities of MR T2-weighted images and calculated the corresponding CV values. CV is defined as the ratio of the standard deviation to the mean. The associations between factors and overall survival (OS) were investigated via the Kaplan-Meier method with log-rank tests and the Cox proportional hazards model.

RESULTS

The mean CV value of MR T2 images was 0.2299 ± 0.1339 (standard deviation) (range, 0.0381-0.8053). Applying receiver operating characteristics analysis, the optimal cut-off level for CV value was 0.137. This cut-off CV value was used for its stratification into high and low CV values. At multivariate survival analysis, a high CV value (hazard ratio = 3.63; 95% confidence interval = 1.16-16.0; p = 0.047) was identified as an independent predictor of OS.

CONCLUSION

The CV value of the signal intensity of heterogenous MPNSTs MR T2-weighted images is an independent predictor of patients' OS.

Impact of postoperative baseline MRI on diagnostic confidence and performance in detecting local recurrence of soft-tissue sarcoma of the limb

OBJECTIVE

To evaluate the impact of a postoperative baseline (PB) MRI on diagnostic confidence and performance in detecting local recurrence (LR) of soft-tissue sarcoma (STS) of the limb.

MATERIALS AND METHODS

A total of 72 patients (8 with LR, 64 without LR) with primary STS of the limb were included. Routine follow-up MRI (1.5 T) at 6 and approximately 36 months (meanLR: 39.7 months; meanno LR: 34.9 months) after multimodal therapy or at time of LR were assessed by three independent readers using a 5-point Likert scale. Furthermore, the following imaging parameters were evaluated: presence of a mass, signal characteristics at T2- and T1-weighted imaging, contrast enhancement (CE), and in some of the cases signal intensity on the apparent diffusion coefficient (ADC). U-test, McNemar test, and ROC-analysis were applied. Interobserver reliability was calculated using Fleiss kappa statistics. A p value of 0.05 was considered statistically significant.

RESULTS

The presence of a PB MRI significantly improved diagnostic confidence in detecting LR of STS (p < 0.001) and slightly increased specificity (mean specificity without PE 74.1% and with presence of PB MRI 81.2%); however, not to a significant level. The presence of a mass showed highest diagnostic performance and highest interreader agreement (AUC [%]; κ: 73.1-83.6; 0.34) followed by T2-hyperintensity (50.8-66.7; 0.08), CE (52.4-62.5; 0.13), and T1-hypointensity (54.7-77.3; 0.23). ADC showed an AUC of 65.6-96.6% and a κ of 0.55.

CONCLUSION

The presence of a PB MRI increases diagnostic confidence in detecting LR of STS of the limb.

[18F]FDG PET/CT in the Initial Staging and Restaging of Soft-Tissue or Bone Sarcoma in Patients with Negative or Equivocal Findings for Metastases or Limited Recurrence on Conventional Work-up: Results of a Prospective Multicenter Registry

The purpose of this study was to determine the impact of [18F]FDG PET/CT on the initial staging, restaging, clinical management, and outcomes of patients with soft-tissue and bone sarcomas. Methods: This single-arm, prospective multicenter registry enrolled 304 patients with 320 [18F]FDG PET/CT scans (November 2018 to October 2021). Eligibility included the initial staging of a grade 2 or higher or ungradable soft-tissue or bone sarcoma, with negative or equivocal findings for nodal or distant metastases on conventional imaging before curative-intent therapy, or restaging of patients with a history of treated sarcoma with a suspicion or confirmation of local recurrence or limited metastatic disease who were being considered for curative-intent or salvage therapy. The presence of local recurrence or metastases on [18F]FDG PET/CT was recorded. Clinical management after [18F]FDG PET/CT compared with pre-[18F]FDG PET/CT planned management and quantitative metabolic tumor parameters (SUVmax, metabolic tumor volume, total lesion glycolysis) were correlated with the outcome data for 171 patients. Results: At the initial staging, [18F]FDG PET/CT detected metastases in 17 of 105 patients (16.2%) with no metastases on conventional work-up and confirmed metastases in 44 of 92 patients (47.8%) with equivocal findings for metastases. At the time of restaging, [18F]FDG PET/CT detected local recurrence in 37 of 123 patients (30.1%) and distant metastases in 71 of 123 patients (57.7%). Overall, the change in treatment intent and treatment type was recorded in 64 of 171 cases (37.4%) and 56 of 171 cases (32.8%), respectively. The presence of metastases on [18F]FDG PET/CT was associated with shorter progression-free survival at the initial staging (P = 0.04) and shorter overall survival at the time of recurrence (P = 0.002). All quantitative metabolic tumor parameters correlated with progression-free survival and overall survival. Conclusion: [18F]FDG PET/CT frequently detects additional sites of disease compared with conventional imaging in patients with sarcomas that were being considered for curative-intent or salvage therapy. This increased detection impacts the clinical management in a third of patients referred for initial staging or presumed limited recurrence after primary therapy. The presence of metastases on [18F]FDG PET/CT is associated with poorer outcomes.

Imaging of pediatric bone tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Malignant primary bone tumors are uncommon in the pediatric population, accounting for 3%-5% of all pediatric malignancies. Osteosarcoma and Ewing sarcoma comprise 90% of malignant primary bone tumors in children and adolescents. This paper provides consensus-based recommendations for imaging in children with osteosarcoma and Ewing sarcoma at diagnosis, during therapy, and after therapy.

Imaging of pediatric extremity soft tissue tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Pediatric soft tissue tumors of the extremity include rhabdomyosarcoma and nonrhabdomyosarcoma neoplasms. This manuscript provides consensus-based imaging recommendations for imaging evaluation at diagnosis, during treatment, and following completion of therapy for patients with a soft tissue tumor of the extremity.

ACR Appropriateness Criteria® Soft Tissue Masses: 2022 Update

Imaging should be performed in patients with a suspected soft tissue mass that cannot be clinically confirmed as benign. Imaging provides essential information necessary for diagnosis, local staging, and biopsy planning. Although the modalities available for imaging of musculoskeletal masses have undergone progressive technological advancements in recent years, their overall purpose in the setting of a soft tissue mass remains unchanged. This document identifies the most common clinical scenarios related to soft tissue masses and the most appropriate imaging for their assessment on the basis of the current literature. It also provides general guidance for those scenarios that are not specifically addressed. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Molecular imaging of sarcomas with FDG PET

Sarcoma comprises a heterogenous entity of musculoskeletal malignancies arising from a mesenchymal origin. The diagnosis and management of pediatric sarcoma requires a multidisciplinary approach and the use of various imaging modalities including CT, MRI and FDG PET scans. FDG PET/CT (FDG PET), as a metabolic imaging, complements and provides superior diagnostic information as against other imaging modalities alone. Advantages of FDG PET in differentiating malignant sarcomatous lesions from benign lesions, and value in staging and restaging have been noted in several studies. The use of FDG PET in clinical management has increased over the years. The data on prognostication of outcomes or predicting responders to therapy with FDG PET in patients with sarcoma is somewhat limited. This review will focus on the pearls and pitfalls of FDG PET and role of FDG PET in initial extent of disease assessment, treatment response, and surveillance imaging pertaining to osteosarcoma, chondrosarcoma, Ewing's sarcoma, and rhabdomyosarcoma. We also discuss the limitations and unmet needs of FDG PET in the management of patients with sarcoma.

Impact of Dynamic Contrast Enhanced and Diffusion-Weighted MR Imaging on Detection of Early Local Recurrence of Soft Tissue Sarcoma

BACKGROUND

Diagnosis of residual or recurrent tumor in soft-tissue sarcomas (STS) is a differential diagnostic challenge since post-therapeutic changes impede diagnosis.

PURPOSE

To evaluate the diagnostic accuracy of quantitative dynamic contrast enhanced (DCE)-MRI and diffusion-weighted imaging (DWI) to detect local recurrence of STS of the limb.

STUDY TYPE

Prospective.

POPULATION

A totalof 64 consecutive patients with primary STS of the limbs were prospectively included 3-6 months after surgery between January 2016 and July 2021.

FIELD STRENGTH/SEQUENCE

A 1.5 T; axial DWI echo-planar imaging sequences and DCE-MRI using a 3D T1-weighted spoiled gradient-echo sequence.

ASSESSMENT

The quantitative DCE-MRI parameters relative plasma flow (rPF) and relative mean transit time (rMTT) were calculated and ADC mapping was used to quantify diffusion restriction. Regions of interest of tumor growth and postoperative changes were drawn in consensus by two experts for diffusion and perfusion analysis. An additional morphological assessment was done by three independent and blinded radiologists.

STATISTICAL TEST

Unpaired t-test, ROC-analysis, and a logistic regression model were applied. Interobserver reliability was calculated using Fleiss kappa statistics. A P value of 0.05 was considered statistically significant.

RESULTS

A total of 11 patients turned out to have local recurrence. rPF was significantly higher in cases of local recurrence when compared to cases without local recurrence (61.1-4.5) while rMTT was slightly and significantly lower in local recurrence. ROC-analysis showed an area under the curve (AUC) of 0.95 (SEM ± 0.05) for rPF while a three-factor multivariate logistic regression model showed a high diagnostic accuracy of rPF (R²  = 0.71). Compared with morphological assessment, rPF had a distinct higher specificity and true positive value in detection of LR.

DATA CONCLUSION

DCE-MRI is a promising additional method to differentiate local recurrence from benign postoperative changes in STS of the limb. Especially specificity in detection of LR is increased compared to morphological assessment.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 2.

PET-CT in the Evaluation of Neoadjuvant/Adjuvant Treatment Response of Soft-tissue Sarcomas: A Comprehensive Review of the Literature

➢

In soft-tissue sarcomas (STSs), the use of positron emission tomography-computed tomography (PET-CT) through a standardized uptake value reduction rate correlates well with histopathological response to neoadjuvant treatment and survival.

➢

PET-CT has shown a better sensitivity to diagnose systemic involvement compared with magnetic resonance imaging and CT; therefore, it has an important role in detecting recurrent systemic disease. However, delaying the use of PET-CT scan, to differentiate tumor recurrence from benign fluorodeoxyglucose uptake changes after surgical treatment and radiotherapy, is essential.

➢

PET-CT limitations such as difficult differentiation between benign inflammatory and malignant processes, inefficient discrimination between benign soft-tissue tumors and STSs, and low sensitivity when evaluating small pulmonary metastases must be of special consideration.

Musculoskeletal Metastasis From Soft-tissue Sarcomas: A Review of the Literature

Soft-tissue sarcomas are a rare and extremely heterogeneous group of cancers, representing <1% of all human malignancies. The lungs are the most common site of distant metastasis, followed by the bone, lymph nodes, liver, brain, and subcutaneous tissue. Clinical experience suggests that skeletal metastasis is part of the natural history affecting the prognosis and quality of life in these patients. Approximately 2.2% of patients have skeletal metastasis at diagnosis. However, up to 10% will develop skeletal metastasis after a mean interval of 21.3 months. Although systemic therapy with conventional chemotherapy remains the primary treatment modality for those with metastatic sarcoma, increased survival has been achieved in selected patients who receive multimodality therapy, including surgery, for their metastatic disease. The 5-year overall survival of patients with isolated bone metastases was 41.2% (26.9% to 54.9%), which decreased to 32.9% (21.2% to 45.1%) in the setting of combined bone and lung metastases. Moreover, the resection of the primary soft-tissue sarcoma is a predictor of survival, resulting in a 58% decrease in mortality after surgery (hazard ratio, 0.42, P = 0.013). Understanding the effect of these metastases on patient survival may influence imaging, surveillance, and treatment decisions.

Radiomics of Musculoskeletal Sarcomas: A Narrative Review

Bone and soft-tissue primary malignant tumors or sarcomas are a large, diverse group of mesenchymal-derived malignancies. They represent a model for intra- and intertumoral heterogeneities, making them particularly suitable for radiomics analyses. Radiomic features offer information on cancer phenotype as well as the tumor microenvironment which, combined with other pertinent data such as genomics and proteomics and correlated with outcomes data, can produce accurate, robust, evidence-based, clinical-decision support systems. Our purpose in this narrative review is to offer an overview of radiomics studies dealing with Magnetic Resonance Imaging (MRI)-based radiomics models of bone and soft-tissue sarcomas that could help distinguish different histotypes, low-grade from high-grade sarcomas, predict response to multimodality therapy, and thus better tailor patients’ treatments and finally improve their survivals. Although showing promising results, interobserver segmentation variability, feature reproducibility, and model validation are three main challenges of radiomics that need to be addressed in order to translate radiomics studies to clinical applications. These efforts, together with a better knowledge and application of the “Radiomics Quality Score” and Image Biomarker Standardization Initiative reporting guidelines, could improve the quality of sarcoma radiomics studies and facilitate radiomics towards clinical translation.

Diagnostic performance of MRI in detecting locally recurrent soft tissue sarcoma: systematic review and meta-analysis

OBJECTIVE

To systematically review the diagnostic criteria and performance of MRI in detecting locally recurrent soft tissue sarcoma.

METHODS

Medline and Embase were searched for original studies on the diagnostic performance of MRI detecting locally recurrent soft tissue sarcoma. Study quality was assessed using QUADAS-2. Sensitivity and specificity were pooled using a bivariate random-effects model.

RESULTS

Ten studies were included. There was a high risk of bias with respect to patient selection in 2 studies and a high risk of bias with respect to flow and timing in 8 studies. The presence of a mass yielded a pooled sensitivity of 80.9% and a pooled specificity of 77.0%. Hyperintensity at T2-weighted imaging yielded a pooled sensitivity of 82.4% and a pooled specificity of 11.0%. Hypo- or isointensity at T1-weighted imaging yielded a pooled sensitivity of 82.0% and a pooled specificity of 14.3%. Contrast enhancement images yielded a pooled sensitivity of 95.9% and a pooled specificity of 12.3%. Low signal mass on the apparent diffusion coefficient (ADC) map yielded a pooled sensitivity of 67.5% and a pooled specificity of 95.3%. Early and rapid arterial phase enhancement at dynamic contrast-enhanced (DCE) MRI yielded a pooled sensitivity of 91.3% and a pooled specificity of 84.7%.

CONCLUSION

The presence of a mass appears a useful criterion to diagnose locally recurrent soft tissue sarcoma. Signal characteristics at standard T2- and T1-weighted imaging and contrast enhancement seem less useful because they lack specificity. Functional MRI techniques, including DWI with ADC mapping and DCE, may help to make a correct diagnosis.

KEY POINTS

• The presence of a mass at MRI appears useful to diagnose locally recurrent soft tissue sarcoma, because both sensitivity and specificity are fairly high. • Signal characteristics at standard T2- and T1-weighted sequences and contrast enhancement suffer from poor specificity. • DWI with ADC mapping and DCE may help to make a correct diagnosis, but further research is needed to better understand the value of these functional MRI techniques.

Concepts in Musculoskeletal Bone and Soft Tissue Biopsy

Imaging-guided needle biopsy of musculoskeletal lesions is a high-yield and low-risk procedure that can be used for definitive characterization of indeterminate bone and soft tissue lesions. Familiarity with the preprocedural, technical, and postprocedural steps is vital for the appropriate management of these cases. Biopsy request triage requires an awareness of definitively benign conditions and other tumor mimics. A complete clinical, laboratory, and imaging work-up is essential for procedural planning and determining pathologic concordance. Consultation with an orthopaedic oncologist is a requisite step to ensure maximizing biopsy yield and to avoid interference with any future limb-sparing surgical intervention. Knowledge of the equipment, pertinent medications, and appropriate biopsy technique can minimize the risk of periprocedural complications. Finally, the radiologist may be required to discuss the concordance of histopathology with preprocedure imaging, perform repeat image-guided biopsy, and carefully interpret sarcoma surveillance imaging examinations.

Imaging update on soft tissue sarcoma

Soft tissue sarcomas (STS) are rare tumours presenting as soft tissue lumps. Ultrasound is often the primary modality for the initial assessment, with MRI the mainstay for lesion characterisation. PET/CT along with other emerging MRI sequences are used in certain situations as an adjunct and problem solving tool in STS staging and assessment of disease recurrence. Recent advances include the promise of whole body MRI, hybrid PET/MRI, diffusion weighted imaging, dynamic contrast enhanced MRI and advances in artificial intelligence. This article discusses current concepts in extremity STS imaging and highlights recent advances.

Deep learning radiomic nomogram to predict recurrence in soft tissue sarcoma: a multi-institutional study

OBJECTIVES

To evaluate the performance of a deep learning radiomic nomogram (DLRN) model at predicting tumor relapse in patients with soft tissue sarcomas (STS) who underwent surgical resection.

METHODS

In total, 282 patients who underwent MRI and resection for STS at three independent centers were retrospectively enrolled. In addition, 113 of the 282 patients received additional contrast-enhanced MRI scans. We separated the participants into a development cohort and an external test cohort. The development cohort consisted of patients from one center and the external test cohort consisted of patients from two other centers. Two MRI-based DLRNs for prediction of tumor relapse after resection of STS were established. We universally tested the DLRNs and compared them with other prediction models constructed by using widespread adopted predictors (i.e., staging systems and Ki67) instead of radiomics features.

RESULTS

The DLRN1 model incorporated plain MRI-based radiomics signature into the clinical data, and the DLRN2 model integrated radiomics signature extracted from plain and contrast-enhanced MRI with the clinical predictors. Across both study sets, the two MRI-based DLRNs had relatively better prognostic capability (C index ≥ 0.721 and median AUC ≥ 0.746; p < 0.05 compared with most other models and predictors) and less opportunity for prediction error (integrated Brier score ≤ 0.159). The decision curve analysis indicates that the DLRNs have greater benefits than staging systems, Ki67, and other models. We selected appropriate cutoff values for the DLRNs to divide STS recurrence into three risk strata (low, medium, and high) and calculated those groups' cumulative risk rates.

CONCLUSION

The DLRNs were shown to be a reliable and externally validated tool for predicting STS recurrence by comparing with other prediction models.

KEY POINTS

• The prediction of a high recurrence rate of STS before emergence of local recurrence can help to determine whether more active treatment should be implemented. • Two MRI-based DLRNs for prediction of tumor relapse were shown to be a reliable and externally validated tool for predicting STS recurrence. • We used the DLRNs to divide STS recurrence into three risk strata (low, medium, and high) to facilitate more targeted postoperative management in the clinic.

Imaging following surgery for primary appendicular bone tumours

Primary bone tumours are uncommon, with sarcomas accounting for < 0.2% of all malignancies. The survival rate of primary bone sarcomas has significantly improved due to (neo)adjuvant therapy, while improved surgical techniques and development of new prostheses have shifted the surgical focus from amputation to limb preservation in the vast majority of patients. A wide variety of surgical options are available for the treatment of primary bone tumours which depend upon histological diagnosis, their appearance at the time of presentation and response to any (neo)adjuvant therapy as required. This review is intended to help radiologists familiarise themselves with the management of primary appendicular bone tumours and expected normal postoperative appearances for the various surgical techniques, and to recognise potential complications.

Magnetic resonance imaging of soft tissue sarcoma: features related to prognosis

Magnetic Resonance Imaging is a fundamental tool in the evaluation of soft tissue sarcoma. Imaging features are relevant for the assessment of treatment strategies, surgical planning and also for patients' prognosis prediction. Among soft tissue sarcoma and also other malignancies, the size of the mass is usually considered the prognostic key element in diagnostic imaging. Moreover, several other features should be obtained from MRI studies with prognostic implications in all type of soft tissue sarcoma: peritumoral enhancement, signs of necrosis, deep location, ill-defined borders/signs of infiltrations. Focusing on soft tissue sarcoma subtypes, some other magnetic resonance imaging features are more specific and related to prognosis. In myxofibrosarcoma the magnetic resonance imaging "tail sign" and a "water-like" appearance on fluid-sensitive sequences, due to rich myxoid matrix content, are both associated with higher risk of local recurrence after surgical excision; nevertheless, the "tail sign" is also related to a higher risk of distant metastases at diagnosis. The "tail sign" is associated with higher risk of local recurrence after surgical excision in undifferentiated pleomorphic sarcoma as well. In patients affected by synovial sarcoma, the "triple sign" identifiable in magnetic resonance imaging (T2w sequences) is associated with decreased disease-free survival and indicates the simultaneous presence of solid cellular elements (intermediate signal intensity), hemorrhage or necrosis (high signal intensity) and fibrotic regions (low signal intensity). In addition, absence of calcifications are associated with reduced disease-free survival in patients affected by synovial sarcoma. Signal heterogeneity is associated with worst prognosis in all type of soft tissue sarcoma, particularly in myxoid liposarcoma. In recent years, several new quantitative tools applied on magnetic resonance imaging have been proved to predict patients' prognosis. Above all the new tools, radiomics seems to be one of the most promising, and, has been proved to have the capability in discriminating low-grade from high-grade soft tissue sarcomas. Therefore, magnetic resonance imaging studies in patients with soft tissue sarcoma should be accurately evaluated and their results should be taken into account for prognostic assessment.

Efficacy and Cost-Benefit Analysis of Magnetic Resonance Imaging in the Follow-Up of Soft Tissue Sarcomas of the Extremities and Trunk

There is no consensus regarding follow-up after soft tissue sarcoma (STS) treatment. This study examines the efficacy and the cost-benefit of MRI imaging for discovering recurrence. A retrospective analysis was performed, collecting data on patient demography, tumor characteristics, treatment, and follow-up. Imaging was correlated to the clinical course, and sensitivity, specificity, and predictive values were calculated. The number needed to screen and costs of finding recurrence are reported. Amongst 216 sarcomas, 73 (35%) exhibited local recurrence during a follow-up of 5.3 ± 3.5 years. 173 entities had complete MRI follow-up with 58 (34%) local recurrences. Thirty-three (57%) were discovered by MRI, 8 (14%) by clinical presentation, and 17 (29%) simultaneously. There was a sensitivity of 100.00%, a specificity of 89%, a positive predictive value of 32%, and a negative predictive value of 100% for detecting local recurrence with MRI. Our data confirm the modalities and intervals proposed by the German guidelines for sarcoma care. The recommended MRI intervals should not be extended. MRI is more cost-effective than clinical examination; still, both modalities should be performed together to discover the maximum number of recurrences.

Gadolinium-based Contrast Agents Improve Detection of Recurrent Soft-Tissue Sarcoma at MRI

Purpose

To determine the diagnostic efficacy of gadolinium-based contrast agents for the detection of recurrent soft-tissue sarcoma compared with non-contrast-enhanced conventional MRI sequences.

Materials and Methods

A retrospective study of patients with soft-tissue sarcomas who were imaged from January 2009 to December 2014 was performed. MRI studies from 69 patients (mean age, 61 years ± 15 [standard deviation], 45 men) with recurrent soft-tissue sarcoma and 63 age-, sex-, and tumor-matched controls with positive findings (nonrecurrence) were presented to six musculoskeletal radiologists at a tertiary cancer center in three image groupings. Group 1 consisted of precontrast T1-weighted and fat-suppressed T2-weighted images (no contrast agent). Group 2 consisted of precontrast and postcontrast fat-saturated T1-weighted images. Group 3 consisted of precontrast and fat-saturated postcontrast T1- and fat-suppressed T2-weighted images. Images within these three groups contained either recurrent soft-tissue sarcomas or positive postoperative findings (nonsarcoma). The presentation order of the first two image sets was reversed for half the readers. The readers were asked to classify presence of tumor on a five-point scale. The average score from the readers was used as consensus score for each case, and a case was considered positive if the average score was less than 3. Receiver operating characteristic (ROC) analysis was performed using the average score for each image set.

Results

Assessment of the group 3 image set resulted in higher sensitivity (74%, 95% confidence interval [CI]: 62%, 83%) than the group 2 image set (64%, 95% CI: 51%, 75%), which was also more sensitive than the assessment of the group 1 images set (49%, 95% CI: 37%, 61%), with P = .02 for both. There was no significant difference in specificity between the three groups. The area under the ROC curve (AUC) for the assessment of group 1 was 0.78 (95% CI: 0.70, 0.86), which was significantly lower than that of group 2, 0.92 (95% CI: 0.87, 0.96) and group 3, 0.93 (95% CI: 0.88, 0.97), with P values of .0006 and < .0001, respectively. There was no difference between the AUCs of groups 2 and 3 (P = .58).

Conclusion

Gadolinium-based contrast agents improved diagnostic performance in detection of recurrent soft-tissue sarcoma. Addition of fat-saturated T2-weighted images provided modest improvement in sensitivity.Keywords: Efficacy Studies, MR-Contrast Agent, Oncology, Soft Tissues/Skin© RSNA, 2020.

Imaging of Soft Tissue Tumors

Differentiation of malignant from benign soft tissue tumors is challenging with imaging alone, including that by magnetic resonance imaging and computed tomography. However, the accuracy of this differentiation has increased owing to the development of novel imaging technology. Detailed patient history and physical examination remain essential for differentiation between benign and malignant soft tissue tumors. Moreover, measurement only of tumor size based on Response Evaluation Criteria In Solid Tumors criteria is insufficient for the evaluation of response to chemotherapy or radiotherapy. Change in metabolic activity measured by ¹⁸F-fluorodeoxyglucose positron emission tomography or dynamic contrast enhanced-derived quantitative endpoints can more accurately evaluate treatment response compared to change in tumor size. Magnetic resonance imaging can accurately evaluate essential factors in surgical planning such as vascular or bone invasion and "tail sign". Thus, imaging plays a critical role in the diagnosis and treatment of soft tissue tumors.

Soft Tissue Sarcoma Follow-up Imaging: Strategies to Distinguish Post-treatment Changes from Recurrence

Soft tissue sarcomas encompass multiple entities with differing recurrence rates and follow-up intervals. The detection of recurrences and their differentiation from post-therapeutic changes is therefore complex, with a central role for the clinical radiologist. This article describes approved recommendations. Prerequisite is a precise knowledge of the current clinical management and surgical techniques. We review recurrence rates and treatment modalities. An adequate imaging technique is paramount, and comparison with previous imaging is highly recommended. We describe time-dependent therapy-related complications on magnetic resonance imaging compared with the spectrum of regular post-therapeutic changes. Early complications such as seromas, hematomas, and infections, late complications such as edema and fibrosis, and inflammatory pseudotumors are elucidated. The appearance of recurrences and radiation-associated sarcomas is contrasted with these changes. This systematic approach in follow-up imaging of soft tissue sarcoma patients will facilitate the differentiation of post-therapeutic changes from recurrences.

The accuracy of a novel sonographic scanning and reporting protocol to survey for soft tissue sarcoma local recurrence

OBJECTIVE

This study aims to determine the accuracy of a novel ultrasonography (US) scanning and reporting protocol to detect recurrences. The secondary aim is to compare US and MRI accuracy and agreement.

MATERIALS AND METHODS

In this IRB-approved prospective study, consecutive patients presenting for MRI surveillance after resection were enrolled and underwent same-day US. Blinded to clinical information and the MRI, the US scanner characterized lesions using a proposed novel lexicon. Outcome was defined either by histology or a subsequent MRI scan confirming the presence or absence of recurrence. Fisher's exact test and Kappa test were performed to assess of the significance and agreement between US, MRI, and outcome.

RESULTS

A total of 68 US scans were performed on 55 patients. The overall accuracy to diagnose recurrence was the same for US and MRI (92.6%) while US was less sensitive (75.0% vs. 91.7%) but more specific (97.6% vs. 92.9%) than MRI. The two lesions missed by US but not MRI were an entirely intraosseous metastasis and a subcentimeter skin nodule. There was strong agreement between US and MRI with outcome (k = 0.787 and 0.801, respectively).

CONCLUSIONS

These pilot data suggest the accuracy of this novel US local recurrence surveillance method is comparable to MRI. A multi-institutional prospective trial would increase power and determine reproducibility.

Functional image in soft tissue sarcomas: An update of the indications of 18F-FDG-PET/CT

Soft tissue sarcomas (STS) are a rare and heterogeneous group of tumors. They account for 1% of solid malignant tumors in adults and 7% in children and are responsible for 2% of cancer mortality. They require a multidisciplinary approach in centers with experience. This collaboration aims to update the scientific evidence to strengthen, together with clinical experience, the bases for the use and limitations of ¹⁸F-FDG-PET/CT in STSs. The general recommendations for the use of PET/CT in STS at present are summarized as the initial evaluation of soft tissue tumours when conventional image does not establish benignity with certainty and this determines the approach; in biopsy guiding in selected cases; in the initial staging, as additional tool, for rhabdomyosarcoma and STS of extremities or superficial trunk and head and neck tumours; in the suspicion of local recurrence when the CT or MRI are inconclusive and in the presence of osteosynthesis or prosthetic material and in assessment of therapy response to local/systemic therapy in stages ii/iii. In addition, PET/CT has the added value of being a surrogate marker of the histopathological response and it provides prognostic information, both in the baseline study and after treatment.

Limb salvage reconstruction: Radiologic features of common reconstructive techniques and their complications

Limb salvage surgery refers to orthopaedic procedures designed to resect tumors and reconstruct limbs. Improvements in managing malignant bone lesions have led to a dramatic shift in limb salvage procedures. Orthopaedic surgeons now employ four main reconstructive procedures: endoprosthesis, autograft, bulk allograft, and allograft prosthetic composite. While each approach has its advantages, each technique is associated with complications. Furthermore, knowledge of procedure specific imaging findings can lead to earlier complication diagnosis and improved clinical outcomes. The aim of this article is to review leading reconstructive options available for limb salvage surgery and present a case series illustrating the associated complications.

Nodal metastases of soft tissue sarcomas: risk factors, imaging findings, and implications

Soft tissue sarcomas (STS) are malignancies derived from connective tissue, and regional lymph node metastasis (RLNM), while not common, is an important aspect of prognosis and treatment. Various risk factors, in particular the histological subtype, affect the likelihood of nodal involvement, which can be characterized by imaging features such as nodal dimension and morphology. Currently, surveillance and management vary by institution, as concrete societal guidelines have not been established. Common nodal status assessment strategies include physical exam, US CT, MRI, sentinel lymph node biopsy (SLNB) and radical lymphadenectomy. This article summarizes data regarding relevant risk factors of RLNM, imaging features, and any available data regarding surveillance recommendations.

Local recurrence of soft tissue sarcoma: a radiomic analysis

Background To perform a radiomics analysis in local recurrence (LR) surveillance of limb soft tissue sarcoma (STS) Patients and methods This is a sub-study of a prospective multicenter study with Institutional Review Board approval supported by ESSR (European Society of Musculoskeletal Radiology). radiomics analysis was done on fast spin echo axial T1w, T2w fat saturated and post-contrast T1w (T1wGd) 1.5T MRI images of consecutively recruited patients between March 2016 and September 2018. Results N = 11 adult patients (6 men and 5 women; mean age 57.8 ± 17.8) underwent MRI to exclude STS LR: a total of 33 follow-up events were evaluated. A total of 198 data-sets per patients of both pathological and normal tissue were analyzed. Four radiomics features were significantly correlated to tumor size (p < 0.02) and four radiomics features were correlated with grading (p < 0.05). ROC analysis showed an AUC between 0.71 (95%CI: 0.55-0.87) for T1w and 0.96 (95%CI: 0.87-1.00) for post-contrast T1w. Conclusions radiomics features allow to differentiate normal tissue from pathological tissue in MRI surveillance of local recurrence of STS. radiomics in STS evaluation is useful not only for detection purposes but also for lesion characterization.

Local recurrence of soft-tissue sarcoma: issues in imaging surveillance strategy

Soft-tissue sarcomas pose diagnostic and therapeutic challenges to physicians, owing to the large number of subtypes, aggressive tumor biology, lack of consensus on management, and controversy surrounding interval and duration of surveillance scans. Advances in multidisciplinary management have improved the care of sarcoma patients, but controversy remains regarding strategies for surveillance following definitive local control. This review provides an updated, comprehensive overview of the current understanding of the risk of local recurrence of soft-tissue sarcoma, by examining the literature based on features such as histological type and grade, tumor size, and resection margin status, with the aim of helping clinicians, surgeons, and radiologists to develop a tailored approach to local imaging surveillance.

Early detection of metastases using whole-body MRI for initial staging and routine follow-up of myxoid liposarcoma

OBJECTIVE

To define the role of whole-body MRI (WBMRI) for initial staging and routine follow-up of myxoid liposarcoma (MLS).

MATERIALS AND METHODS

A retrospective review of all the patients with MLS who underwent WBMRI for initial staging and routine follow-up at our institution between October 1, 2006, and September 30, 2016 was performed. Patient demographics, clinical presentation, imaging findings, tumor histology, and occurrence and location of metastatic disease were recorded. Thirty-three patients who underwent a total of 150 WBMRI examinations were included in the study.

RESULTS

Nine patients (27%) were diagnosed with metastases between 0 and 60 months (median 10; interquartile range, 7-13) from the diagnosis of the primary tumor. The initial site of metastatic disease was extrapulmonary in all patients. Only two patients developed pulmonary metastases, which were diagnosed by CT chest 9 and 29 months after the diagnosis of extrapulmonary metastases. The first metastasis was diagnosed by WBMRI in seven patients (78%), by thoracic CT in one patient, and by abdominal CT in one patient. Eight of nine patients (89%) were asymptomatic at the time of diagnosis of the metastases. In seven patients (78%), WBMRI demonstrated metastases included within the field of view of, but occult on a contemporaneous CT scan.

CONCLUSION

Our 10-year institutional experience demonstrates that WBMRI facilitates early detection of extrapulmonary MLS metastases before the onset of clinical symptoms and pulmonary metastases. WBMRI also depicts extrapulmonary metastases that are occult on CT scans. The current surveillance strategies are insufficient for screening for extrapulmonary MLS metastases.

Follow-up after initial surgical treatment of soft tissue sarcomas in the extremities and trunk wall

BACKGROUND/OBJECTIVES

Evaluation of our surveillance program for soft tissue sarcomas (STS) and borderline tumors (BT) for identification of local recurrence and lung metastases the first 2 years postoperatively.

METHODS

We retrospectively assessed the medical files of all patients (n = 232) with STS and BT of the extremities and trunk wall who underwent surgery from 2010 to 2013. Two-hundred-and-thirty-two patients were included in the local recurrence study and 116 patients in the lung metastasis study. We extracted information on how local recurrence and lung metastases were detected. Kaplan-Meier survival analysis and 2 × 2-contingency table with Chi-square test were used. Local recurrence and lung metastases were analyzed separately.

RESULTS

Twenty-five of 232 patients experienced local recurrence and 19 of 116 patients experienced lung metastases. Compared to clinical examination, local imaging led to a larger amount of local recurrence suspicions (37/560 vs. 8/706). Suspicions occurring on local imaging were more accurate than on clinical examination (17/37 vs. 0/8 affirmed). Local imaging identified a larger amount of local recurrence than clinical examination (17/560 vs. 0/706). Thirty-three patients suspected local recurrence themselves, 8 were affirmed. Compared to x-ray, computerized tomography (CT) led to a larger amount of lung metastasis suspicions (22/284 vs. 6/276). Suspicions occurring on CT seemed more accurate than on x-ray (15/22 vs. 2/6 affirmed). CT found a larger amount of lung metastases than x-ray (15/284 vs. 2/276). Three patients suspected lung metastases themselves, 1 was affirmed.

CONCLUSION

Bi-annual local imaging and CT the first 2 years after surgery of STS detect local recurrence and lung metastases better than clinical examination and x-ray. Clinical examination and x-ray between these examinations is unnecessary. Patients' own suspicion of local recurrence and lung metastases is still important.