Pseudolesions involving bone and soft tissue regarding orthopedic oncology.

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

Musculoskeletal Pitfalls on Molecular Imaging Studies of Oncologic Patients: How to Stay Out of Trouble.

An increasing amount of molecular imaging studies are ordered each year for an oncologic population that continues to expand and increase in age. The importance of these studies in dictating further care for oncologic patients underscores the necessity of differentiating benign from malignant findings, particularly for a population in whom incidental findings are common. The aim of this review is to provide pictorial examples of benign musculoskeletal pathologies which may be found on molecular imaging and which may be mistaken for malignant processes. Imaging examples are provided in the form of radiographs, bone scintigraphy, computed tomography, and fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scans. Special attention is paid to specific features that help narrow the differential diagnosis and distinguish benign from malignant processes, with the goal of avoiding unnecessary invasive procedures.

MRI-based Neuropathy Score Reporting And Data System (NS-RADS): multi-institutional wider-experience usability study of peripheral neuropathy conditions among 32 radiology readers.

OBJECTIVE: To determine the inter-reader reliability and diagnostic performance of classification and severity scales of Neuropathy Score Reporting And Data System (NS-RADS) among readers of differing experience levels after limited teaching of the scoring system. METHODS: This is a multi-institutional, cross-sectional, retrospective study of MRI cases of proven peripheral neuropathy (PN) conditions. Thirty-two radiology readers with varying experience levels were recruited from different institutions. Each reader attended and received a structured presentation that described the NS-RADS classification system containing examples and reviewed published articles on this subject. The readers were then asked to perform NS-RADS scoring with recording of category, subcategory, and most likely diagnosis. Inter-reader agreements were evaluated by Conger's kappa and diagnostic accuracy was calculated for each reader as percent correct diagnosis. A linear mixed model was used to estimate and compare accuracy between trainees and attendings. RESULTS: Across all readers, agreement was good for NS-RADS category and moderate for subcategory. Inter-reader agreement of trainees was comparable to attendings (0.65 vs 0.65). Reader accuracy for attendings was 75% (95% CI 73%, 77%), slightly higher than for trainees (71% (69%, 72%), p = 0.0006) for nerves and comparable for muscles (attendings, 87.5% (95% CI 86.1-88.8%) and trainees, 86.6% (95% CI 85.2-87.9%), p = 0.4). NS-RADS accuracy was also higher than average accuracy for the most plausible diagnosis for attending radiologists at 67% (95% CI 63%, 71%) and for trainees at 65% (95% CI 60%, 69%) (p = 0.036). CONCLUSION: Non-expert radiologists interpreted PN conditions with good accuracy and moderate-to-good inter-reader reliability using the NS-RADS scoring system. CLINICAL RELEVANCE STATEMENT: The Neuropathy Score Reporting And Data System (NS-RADS) is an accurate and reliable MRI-based image scoring system for practical use for the diagnosis and grading of severity of peripheral neuromuscular disorders by both experienced and general radiologists. KEY POINTS: • The Neuropathy Score Reporting And Data System (NS-RADS) can be used effectively by non-expert radiologists to categorize peripheral neuropathy. • Across 32 different experience-level readers, the agreement was good for NS-RADS category and moderate for NS-RADS subcategory. • NS-RADS accuracy was higher than the average accuracy for the most plausible diagnosis for both attending radiologists and trainees (at 75%, 71% and 65%, 65%, respectively).

Paediatric sand toe: radiographic, ultrasound and MRI findings of dorsomedial capsular injury.

Hyperflexion injury to the metatarsophalangeal joint of the great toe, referred to as sand toe, can cause significant functional impairment. To our knowledge, there have been no radiological descriptions of this injury in the paediatric age group. Here, we report radiographic, sonographic and MRI findings in a male paediatric patient who sustained a sand toe injury, highlighting structural damage to the dorsomedial capsule and medial sagittal band, and discuss sand toe's favourable prognosis with conservative management.

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

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

Unusual lipid poor spindle cell lipoma.

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

CivaSheet® use for soft tissue sarcoma: A single institution experience.

OBJECTIVE: CivaSheet is a palladium-103, implantable, intraoperative radiation therapy device which emits unidirectional radiation that enables boost doses in patients who have otherwise received the maximum radiation dose. Here, we present our initial clinical experience with the first 10 cases using this new technology. METHODS AND MATERIALS: A retrospective chart review of all patients with STS treated with surgical resection and CivaSheet placement at the University of Miami Hospital, a tertiary care center, from January 2018 to December 2019, was performed. Adjuvant radiation was administered by a palladium-103 implant, which delivered an average of 47 Gy (35-55) to a depth of 5 mm. RESULTS: Nine patients underwent CivaSheet placement from January 2018 until December 2019 for a total of 10 CivaSheets placed (1 patient had 2 CivaSheets inserted) and followed for a mean of 27 months (4-45 months). Four tumors were located in the retroperitoneum, two in the chest, two in the groin, and two within the lower extremity. At the time of tumor resection and CivaSheet placement, tumor sizes ranged from 2.5 cm to 13.8 cm with an average of 7.6 cm. Four patients necessitated musculocutaneous tissue flaps for closure and reconstruction. All patients with Grade 4 complications had flap reconstruction and prior radiation. Four patients' tumors recurred locally for a local recurrence rate of 40%. Three patients had modified accordion Grade 4 complications necessitating additional surgery for CivaSheet removal. Extremity tumors unanimously developed modified accordion Grade 4 adverse events. CONCLUSIONS: CivaSheet may be an acceptable alternative treatment modality compared to prior brachytherapy methods.

Soft Tissue Masses of the Hand: A Review of Clinical Presentation and Imaging Features.

More than 15% of all soft-tissue tumors arise in the hand. Because of the location of these tumors, even small abnormalities may be alarming to patients on presentation. Although the majority of lesions are benign and can be diagnosed solely by history and physical examination, additional imaging workup may be required to confirm a diagnosis or define anatomic extent of involvement. This paper aims to review the basic epidemiology, clinical presentation, imaging findings, and treatment options of the more common soft-tissue tumors of the hand.

Benign Bone Lesions Found in Childhood.

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

MRI T2 mapping assessment of T2 relaxation time in desmoid tumors as a quantitative imaging biomarker of tumor response: preliminary results.

Objectives: Because size-based imaging criteria poorly capture biologic response in desmoid-type fibromatosis (DF), changes in MRI T2 signal intensity are frequently used as a response surrogate, but remain qualitative. We hypothesized that absolute quantification of DF T2 relaxation time derived from parametric T2 maps would be a feasible and effective imaging biomarker of disease activity. Methods: This IRB-approved retrospective study included 11 patients with DF, managed by observation or systemic therapy, assessed by 3T MRI. Tumor maximum diameter, volume, and T2-weighted signal intensity were derived from manual tumor segmentations. Tumor:muscle T2 signal ratios were recorded. Two readers measured tumor T2 relaxation times using a commercial T2 scanning sequence, manual ROI delineation and commercial calculation software enabling estimation of reader reliability. Objective response rates based on RECIST1.1 and best responses were compared between size-based and signal-based parameters. Results: Median patient age was 52.6 years; 8 subjects were female (73%). Nine patients with longitudinal assessments were followed for an average of 314 days. Median baseline tumor diameter was 7.2 cm (range 4.4 - 18.2 cm). Median baseline T2 was 65.1 ms (range 40.4 - 94.8 ms, n=11); median at last follow-up was 44.3 ms (-32% from baseline; range 29.3 - 94.7 ms, n=9). T2 relaxation times correlated with tumor:muscle T2 signal ratios, Spearman p=0.78 (p<0.001). T2 mapping showed high inter-reader reliability, ICC=0.84. The best response as a percentage change in T2 values was statistically significant (mean -17.9%, p=0.05, paired t-test) while change in diameter was not (mean -8.9%, p=0.12). Conclusions: Analysis of T2 relaxation time maps of DF may offer a feasible quantitative biomarker for assessing the extent of response to treatment. This approach may have high inter-reader reliability.

Radiologic screening and surveillance in hereditary cancers.

Hereditary cancer syndromes comprise an important subset of cancers caused by pathogenic germline mutations that can affect various organ systems. Radiologic screening and surveillance for solid tumors has emerged as a critical component of patient management in permitting early cancer detection. Although imaging surveillance may be tailored for organ-specific cancer risks, surveillance protocols frequently utilize whole-body MRI or PET/CT because of their ability to identify neoplasms in different anatomic regions in a single exam. In this review, we discuss the basic tenets of imaging screening and surveillance strategies in these syndromes, highlighting the more common neoplasms and their associated multimodality imaging findings.

Teaching cancer imaging in the era of precision medicine: Looking at the big picture.

The role of imaging in cancer diagnosis and treatment has evolved at the same rapid pace as cancer management. Over the last twenty years, with the advancement of technology, oncology has become a multidisciplinary field that allows for researchers and clinicians not only to create individualized treatment options for cancer patients, but also to evaluate patients' response to therapy with increasing precision. Familiarity with these concepts is a requisite for current and future radiologists, as cancer imaging studies represent a significant and growing component of any radiology practice, from tertiary cancer centers to community hospitals. In this review we provide the framework to teach cancer imaging in the era of genomic oncology. After reading this article, readers should be able to illustrate the basics cancer genomics, modern cancer genomics, to summarize the types of systemic oncologic therapies available, their patterns of response and their adverse events, to discuss the role of imaging in oncologic clinical trials and the role of tumor response criteria and to display the future directions of oncologic imaging.

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.

Neuropathy Score Reporting and Data System: A Reporting Guideline for MRI of Peripheral Neuropathy With a Multicenter Validation Study.

BACKGROUND. A standardized guideline and scoring system would improve evaluation and reporting of peripheral neuropathy (PN) on MRI. OBJECTIVE. The objective of this study was to create and validate a neuropathy classification and grading system, which we named the Neuropathy Score Reporting and Data System (NS-RADS). METHODS. This retrospective study included 100 patients with nerve imaging studies and known clinical diagnoses. Experts crafted NS-RADS using mutually agreed-on qualitative criteria for the classification and grading of PN. Different classes were created to account for the spectrum of underlying pathologies: unremarkable (U), injury (I), neoplasia (N), entrapment (E), diffuse neuropathy (D), not otherwise specified (NOS), and postintervention state (PI). Subclasses were established to describe the severity or extent of the lesions. Validation testing was performed by 11 readers from 10 institutions with experience levels ranging from 3 to 18 years after residency. After initial reader training, cases were presented to readers who were blinded to the final clinical diagnoses. Interobserver agreement was assessed using correlation coefficients and the Conger kappa, and accuracy testing was performed. RESULTS. Final clinical diagnoses included normal (n = 5), nerve injury (n = 25), entrapment (n = 15), neoplasia (n = 33), diffuse neuropathy (n = 18), and persistent neuropathy after intervention (n = 4). The miscategorization rate for NS-RADS classes was 1.8%. Final diagnoses were correctly identified by readers in 71-88% of cases. Excellent inter-reader agreement was found on the NS-RADS pathology categorization (κ = 0.96; 95% CI, 0.93-0.98) as well as muscle pathology categorization (κ = 0.76; 95% CI, 0.68-0.82). The accuracy for determining milder versus more severe categories per radiologist ranged from 88% to 97% for nerve lesions and from 86% to 94% for muscle abnormalities. CONCLUSION. The proposed NS-RADS classification is accurate and reliable across different reader experience levels and a spectrum of PN conditions. CLINICAL IMPACT. NS-RADS can be used as a standardized guideline for reporting PN and improved multidisciplinary communications.

Soft Tissue Tumors: Imaging Features of Primary Soft Tissue Malignancies.

Imaging in soft tissue sarcomas (STS) plays a key role in diagnosis, surgical planning, and assessment of treatment response, and surveillance. In this review, we discuss the imaging features-with an emphasis on MR imaging-of nonvisceral STS, highlighting representative tumors from the various WHO subtypes. We focus on imaging findings that may aid the radiologist in categorizing tumor subtype and grade, and that affect disease staging.

Systemic Chemotherapies Retain Antitumor Activity in Desmoid Tumors Independent of Specific Mutations in CTNNB1 or APC: A Multi-institutional Retrospective Study.

PURPOSE: Determine whether specific CTNNB1 or APC mutations in patients with desmoid tumor were associated with differences in clinical responses to systemic treatments. EXPERIMENTAL DESIGN: We established a multi-institutional dataset of previously treated patients with desmoid tumor across four U.S. sarcoma centers, including demographic and clinicopathologic characteristics, treatment regimens, and clinical and radiographic responses. CTNNB1 or APC mutation status was determined from prior pathology records, or archival tissue was requested and analyzed by Sanger sequencing and/or next-generation sequencing. Evaluable patients with mutation results were analyzed to determine clinical progression-free survival (cPFS), RECIST 1.1 PFS (rPFS), time to next treatment (TTNT), and overall survival (OS). Kaplan-Meier analysis and Cox proportional hazards regression were performed to identify differences in cPFS, rPFS, TTNT, and OS by mutation subtype, desmoid tumor location, and treatment regimen. RESULTS: A total of 259 evaluable patients were analyzed for at least one of the survival outcomes, with 177 patients having mutation data. First- and second-line cPFS, rPFS, and TTNT were not significantly affected by mutation subtype; however, APC-mutant desmoid tumors demonstrated nonstatistically significant inferior outcomes. Extremity/trunk desmoid tumor location and treatment with doxorubicin-based, methotrexate/vinca alkaloids and sorafenib regimens were associated with better clinical outcomes compared with surgery or "other" therapies, including estrogen-receptor blockade and imatinib. OS was significantly worse with APC or CTNNB1 negative/other mutations. CONCLUSIONS: Mutation subtype did not affect responses to specific systemic therapies. APC mutations and nonextremity desmoid tumor locations remain prognostic for worse outcomes, and earlier initiation of systemic therapy for these higher-risk desmoid tumors should be prospectively evaluated. See related commentary by Greene and Van Tine, p. 3911.

Systematic review: investigating the added diagnostic value of gadolinium contrast agents for osteomyelitis in the appendicular skeleton.

OBJECTIVE: Osteomyelitis is an infection of the bone marrow. MRI with gadolinium-based contrast is frequently performed for cases of suspected osteomyelitis. The objective of this systematic review is to examine the diagnostic accuracy of contrast-enhanced vs non-contrast-enhanced MRI for osteomyelitis in the appendicular skeleton. MATERIALS AND METHODS: We conducted a systematic review of MRI in the diagnosis of osteomyelitis by searching MEDLINE and EMBASE from January 2000 to March 2020. There were 21 studies that met the inclusion criteria for the systematic review for a total of 1095 patients. Analytic methods were based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Evidence was evaluated using the STARD criteria for evaluation of completeness and transparency of reporting. RESULTS: For diagnosing osteomyelitis in the appendicular skeleton, MRI with gadolinium-based contrast has 89% sensitivity (95% CI, 86-92%), 79% specificity (95% CI, 75-83%), and 90% overall diagnostic accuracy ([SE] = 0.03). For diagnosing osteomyelitis in the appendicular skeleton, MRI without gadolinium-based contrast has a 92% sensitivity (95% CI, 87-96%), 89% specificity (95% CI, 84-93%), and 96% overall diagnostic accuracy ([SE] = 0.03). The median score of included studies was 85% utilizing the STARD criteria with excellent interobserver agreement of 83.4%. Limitations included small sample size of studies, with retrospective designs. CONCLUSION: No evidence was found to suggest an added diagnostic value of gadolinium contrast for the diagnosis of osteomyelitis in the appendicular skeleton. For routine cases of suspected non-spinal osteomyelitis, non-contrast MRI of the area of interest is the next most appropriate study after radiographs.

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.

Genomic Landscape of Angiosarcoma: A Targeted and Immunotherapy Biomarker Analysis.

We performed a retrospective analysis of angiosarcoma (AS) genomic biomarkers and their associations with the site of origin in a cohort of 143 cases. Primary sites were head and neck (31%), breast (22%), extremity (11%), viscera (20%), skin at other locations (8%), and unknown (9%). All cases had Next Generation Sequencing (NGS) data with a 592 gene panel, and 53 cases had Whole Exome Sequencing (WES) data, which we used to study the microenvironment phenotype. The immunotherapy (IO) response biomarkers Tumor Mutation Burden (TMB), Microsatellite Instability (MSI), and PD-L1 status were the most frequently encountered alteration, present in 36.4% of the cohort and 65% of head and neck AS (H/N-AS) (p < 0.0001). In H/N-AS, TMB-High was seen in 63.4% of cases (p < 0.0001) and PDL-1 positivity in 33% of cases. The most common genetic alterations were TP53 (29%), MYC amplification (23%), ARID1A (17%), POT1 (16%), and ATRX (13%). H/N-AS cases had predominantly mutations in TP53 (50.0%, p = 0.0004), POT1 (40.5%, p < 0.0001), and ARID1A (33.3%, p = 0.5875). In breast AS, leading alterations were MYC amplification (63.3%, p < 0.0001), HRAS (16.1%, p = 0.0377), and PIK3CA (16.1%, p = 0.2352). At other sites, conclusions are difficult to generate due to the small number of cases. A microenvironment with a high immune signature, previously associated with IO response, was evenly distributed in 13% of the cases at different primary sites. Our findings can facilitate the design and optimization of therapeutic strategies for AS.