Bone Tumor Risk Stratification and Management System: A Consensus Guideline from the ACR Bone Reporting and Data System Committee

The assessment and subsequent management of a potentially neoplastic bone lesion seen at diagnostic radiography is often complicated by diagnostic uncertainty and inconsistent management recommendations. Appropriate clinical management should be directed by risk of malignancy. Herein, the ACR-sponsored Bone Reporting and Data System (Bone-RADS) Committee, consisting of academic leaders in the fields of musculoskeletal oncology imaging and orthopedic oncology, presents the novel Bone-RADS scoring system to aid in risk assignment and provide risk-aligned management suggestions. When viewed in the proper clinical context, a newly identified bone lesion can be risk stratified as having very low, low, intermediate, or high risk of malignancy. Radiographic features predictive of risk are reviewed include margination, pattern of periosteal reaction, depth of endosteal erosion, pathological fracture, and extra-osseous soft tissue mass. Other radiographic features predictive of histopathology are also briefly discussed. To apply the Bone-RADS scoring system to a potentially neoplastic bone lesion, radiographic features predictive of risk are each given a point value. Point values are summed to yield a point total, which can be translated to a Bone-RADS score (1-4) with corresponding risk assignment (very low, low, intermediate, high). For each score, evidence-based and best practice consensus management suggestions are outlined. Examples of each Bone-RADS scores are presented, and a standardized diagnostic radiography report template is provided.

ACR Appropriateness Criteria® Chronic Hip Pain: 2022 Update

Chronic hip pain is a frequent chief complaint for adult patients who present for evaluation in a variety of clinical practice settings. Following a targeted history and physical examination, imaging plays a vital role in elucidating the etiologies of a patient's symptoms, as a wide spectrum of pathological entities may cause chronic hip pain. Radiography is usually the appropriate initial imaging test following a clinical examination. Depending on the clinical picture, advanced cross-sectional imaging may be subsequently performed for further evaluation. This documents provides best practice for the imaging workup of chronic hip pain in patients presenting with a variety of clinical scenarios. 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 include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Chronic Extremity Joint Pain-Suspected Inflammatory Arthritis, Crystalline Arthritis, or Erosive Osteoarthritis: 2022 Update

Evaluation for suspected inflammatory arthritis as a cause for chronic extremity joint pain often relies on imaging. It is essential that imaging results are interpreted in the context of clinical and serologic results to add specificity because there is significant overlap of imaging findings among the various types of arthritis. This document provides recommendations for imaging evaluation of specific types of inflammatory arthritis, including rheumatoid arthritis, seronegative spondyloarthropathy, gout, calcium pyrophosphate dihydrate disease (or pseudogout), and erosive osteoarthritis. The ACR 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 in which peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Suspected Osteomyelitis, Septic Arthritis, or Soft Tissue Infection (Excluding Spine and Diabetic Foot): 2022 Update

Musculoskeletal infections involve bones, joints, and soft tissues. These infections are a common clinical scenario in both outpatient and emergent settings. Although radiography provides baseline findings, a multimodality approach is often implemented to provide more detailed information on the extent of infection involvement and complications. MRI with intravenous contrast is excellent for the evaluation of musculoskeletal infections and is the most sensitive for diagnosing osteomyelitis. MRI, CT, and ultrasound can be useful for joint and soft tissue infections. When MRI or CT is contraindicated, bone scans and the appropriate utilization of other nuclear medicine scans can be implemented for aiding in the diagnostic imaging of infection, especially with metal hardware and arthroplasty artifacts on MRI and CT. The ACR 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 in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Malignant or Aggressive Primary Musculoskeletal Tumor-Staging and Surveillance: 2022 Update

Malignant or aggressive primary musculoskeletal tumors are rare and encompass a wide variety of bone and soft tissue tumors. Given the most common site for metastasis from these primary musculoskeletal tumors is to the lung, chest imaging is integral in both staging and surveillance. Extrapulmonary metastases are rarely encountered with only a few exceptions. Following primary tumor resection, surveillance of the primary tumor site is generally recommended. Local surveillance imaging recommendations differ between primary tumors of bone origin versus soft tissue origin. This document consolidates the current evidence and expert opinion for the imaging staging and surveillance of these tumors into five clinical scenarios. The ACR 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 in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Chronic Elbow Pain

Chronic elbow pain can be osseous, soft tissue, cartilaginous, and nerve related in etiology. Imaging plays an important role in differentiating between these causes of chronic elbow pain. This document provides recommendations for imaging of chronic elbow pain in adult patients. The ACR 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 in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Unusual Presentation of Widely Metastatic Extraskeletal Osteosarcoma: Case Report

Extraskeletal osteosarcoma is a highly aggressive malignant osteoid forming mesenchymal neoplasm arising from soft tissues which accounts for 1% of all soft tissue sarcomas. We report the case of a 46-year-old female with no significant past medical history presenting to an emergency department with a right lateral thigh mass following minor trauma. She was eventually found to have high grade extraskeletal osteosarcoma with rapid progression of disease resulting in patient demise. Differentiation of these lesions from alternative processes relies on specific imaging and pathologic features. Differential diagnoses include both benign and malignant etiologies such as myositis ossificans, soft tissue hemangiomas, and other malignant soft tissue neoplasms such as epithelial and synovial sarcoma.

Retropubic parasymphyseal cyst: A rare entity

We report a case of a retropubic parasymphyseal cyst in a 69-year-old multiparous female with a protracted history of metastatic small bowel carcinoid (neuroendocrine) tumor. Cysts related to the pubic symphysis are uncommon, and mostly reported in subpubic location. They may be confused with primary vulvar masses, malignant bone tumors or metastatic disease. In our case, encapsulation, lack of solid components or diffusion restriction, communication with the symphysis, lack of activity on Gallium-68-Dotatate PET/CT and signal characteristics on MRI similar to those previously reported in literature for subpubic cysts all aided in eventual diagnosis. We aim to remind the reader of this rare entity and its distinguishing features on imaging.

Synovial sarcoma of bone: Sarcoma typically of soft tissues presenting as a primary bone tumor

Synovial sarcoma typically presents as periarticular soft tissue mass in adolescent and young adult patients. Very rarely, soft tissue sarcomas may arise primarily within bone posing a significant diagnostic challenge as primary osseous malignancies such as osteosarcoma and metastatic disease are much more common. While tissue sampling with immunohistochemical and genetic testing are required for definitive diagnosis, radiologists and orthopedic oncologists should consider alternate etiologies when typical imaging features of more common bone tumors are not identified. As an example, we present a 33-year-old male referred with a pathologic hip fracture proven to represent primary synovial sarcoma of bone.

Paratesticular Liposarcoma Masquerading as an Inguinal Hernia

A man with left scrotal swelling felt to represent inguinal hernia underwent computed tomography scan for reported bleeding after prostate biopsy. Computed tomography scan revealed a 15-cm extratesticular left scrotal mass containing both fat and soft tissue components, raising concern for dedifferentiated liposarcoma. At surgery and pathology, the mass was separate from the left testis, epididymis, and spermatic cord. Histopathologic findings were consistent with paratesticular dedifferentiated liposarcoma.

A report of two deep-seated noncutaneous penile tumors: more than meets the eye

Penile cancer is an uncommon primary genitourinary malignancy, the vast majority representing superficial squamous cell carcinomas. However, less common skin cancers, secondary malignancies, mesenchymal neoplasms, and hematopoietic tumors do affect the penis. Medical history, atypical presentation, and deep epicenter of a penile mass may raise question of a nonepithelial neoplasm. We describe and discuss 2 examples of rare deep-seated penile malignancies, leiomyosarcoma and B-cell lymphoma.

Solid variant aneurysmal bone cyst in the distal fibular metaphysis: radiologic and pathologic challenges to diagnosis

Solid variant aneurysmal bone cyst is a rare benign bone lesion, representing a small fraction of all aneurysmal bone cysts. The imaging appearance and histologic features may overlap with other benign and malignant neoplasms, posing a diagnostic dilemma for clinicians, pathologists, and radiologists. We present a case of solid variant aneurysmal bone cyst of the distal fibula and review the radiologic and histologic features important for diagnosis.

Practical Issues for Retroperitoneal Sarcoma

Background

Retroperitoneal sarcoma is rare. Using initial specimens on biopsy, a definitive diagnosis of histological subtypes is ideal but not always achievable.

Methods

A retrospective institutional review was performed for all cases of adult retroperitoneal sarcoma from 1996 to 2015. A review of the literature was also performed related to the distribution of retroperitoneal sarcoma subtypes. A meta-analysis was performed.

Results

Liposarcoma is the most common subtype (45%), followed by leiomyosarcoma (21%), not otherwise specified (8%), and undifferentiated pleomorphic sarcoma (6%) by literature review. Data from Moffitt Cancer Center demonstrate the same general distribution for subtypes of retroperitoneal sarcoma. A pathology-based algorithm for the diagnosis of retroperitoneal sarcoma is illustrated, and common pitfalls in the pathology of retroperitoneal sarcoma are discussed.

Conclusions

An informative diagnosis of retroperitoneal sarcoma via specimens on biopsy is achievable and meaningful to guide effective therapy. A practical and multidisciplinary algorithm focused on the histopathology is helpful for the management of retroperitoneal sarcoma.

Cystic lesions of the pancreas: radiologic-endosonographic correlation

Cystic lesions of the pancreas are relatively common findings at cross-sectional imaging; however, classification of these lesions on the basis of imaging features alone can sometimes be difficult. Complementary evaluation with endoscopic ultrasonography and fine-needle aspiration may be helpful in the diagnosis of these lesions. Cystic lesions of the pancreas may range from benign to malignant and include both primary cystic lesions of the pancreas (including intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, serous cystadenomas, pseudocysts, and true epithelial cysts) and solid neoplasms undergoing cystic degeneration (including neuroendocrine tumors, solid pseudopapillary neoplasms, and, rarely, adenocarcinoma and its variants). Familiarity with the imaging features of these lesions and the basic treatment algorithms is essential for radiologists, as collaboration with gastroenterologists and surgeons is often necessary to obtain an early and accurate diagnosis.

Giant cell tumor of the anterior rib masquerading as a breast mass: a case report and review of current literature

INTRODUCTION

Giant cell tumor (GCT) is an aggressive, but usually benign bone neoplasm most commonly arising in the metaphysis/epiphyses of long bones. While they are categorized as benign tumors, they can be locally aggressive and clinically have metastatic potential. The most common locations of this tumor include the distal femur, proximal tibia, and distal radius. We report a GCT arising in an atypical location and mimicking a breast mass.

CASE PRESENTATION

This case was diagnosed at a large cancer center in Florida. Pertinent clinical findings were obtained from chart review and inter-departmental consultation. Radiologically, the initial impression included a deep-seated breast cancer with local chest wall invasion. Further evaluation revealed the mass to be an expansile rib lesion with extraosseous soft tissue invasion. Histological examination of the biopsy specimen showed bland multi-nucleated giant cells and mononuclear cells whose nuclei were morphologically similar. No necrosis, pleomorphism or mitotic activity was identified. No chondroid or osseous elements were present.

CONCLUSION

The histological features of bland mononuclear and multinucleated giant cells along with the lack of any additional mesenchymal elements led to the diagnosis of giant cell tumor. Resection of tumor was performed. The patient is disease free as of the last follow-up visit. This case is important as it shows where the physician must keep this diagnosis in mind whenever a deeply located breast mast is present.

Squamous cell carcinoma and osteosarcoma arising from a dermoid cyst--a case report and review of literature

A rare case of multiple malignant tumors (poorly differentiated squamous cell carcinoma and high grade osteosarcoma) arising in an ovarian dermoid cyst of a 55 year old female is reported. To the best of our knowledge, this is the first well documented example of such an unusual combination of tumors arising in a dermoid cyst. The osteosarcoma and squamous cell carcinoma appear to arise in the background of benign teratomatous environment of a dermoid cyst rather than from "pure" mixed mesodermal tumors of the ovary. The tumors did not appear to have well demarcated boundaries with a junction or close intermingling of both cell types, features less favorable for collision tumor or carcinosarcoma. Despite extensive surgery with negative surgical margins and combination chemotherapy, the patient had recurrence of the tumor within four months and she died secondary to septicemia to chemotherapy and bilateral pulmonary emboli shortly after.

CT findings associated with Eagle syndrome

Eagle syndrome is an aggregate of symptoms caused by an elongated ossified styloid process, the cause of which remains unclear. This is a rare finding that often goes undetected in the absence of radiographic studies. In this case, we present the diagnostic CT and lateral view plain film radiography findings of a 39-year-old woman with clinical evidence of Eagle syndrome. Eagle syndrome can occur unilaterally or bilaterally and most frequently results in symptoms of dysphagia, headache, pain on rotation of the neck, pain on extension of the tongue, change in voice, and a sensation of hypersalivation (1, 2). We present rare and diagnostic radiographic evidence of this on both plain film radiographs and CT scans. Although well documented in otolaryngology literature and dentistry literature, this syndrome has not been reported in the radiology literature.

Pathognomonic MR imaging findings in Balo concentric sclerosis

Irregular, concentric zones of increased signal on T2-weighted cranial MR imaging studies may strongly suggest Balo concentric sclerosis (BCS), a rare but recognized variant of multiple sclerosis. Differentiating BCS from multiple sclerosis or neoplasm can be difficult clinically, but MR imaging findings noted in this case may be pathognomonic.