Radiologie (Heidelberg, Germany)最新文献

Chondrosarcomas are tumours that typically occur in older adults. Although a few arise de novo, they often develop from pre-existing enchondromas, much more frequently from osteochondromas. In these secondary chondrosarcomas, the primary site of pre-existing chondrogenic lesion plays an important role (close to the trunk, centrally; appendicular skeleton, peripherally). Thus, low-grade chondrosarcomas in the periphery are referred to as atypical chondrogenic tumours (ACT), whereas tumours of the same histopathological type located close to the axial skeleton are called chondrosarcoma grade 1. Syndromal occurrence (Ollier's and Maffucci's diseases) carries a significantly higher risk of malignant transformation. Other malignant primary bone tumours being much less frequent exhibit an unspecific osteolytic morphology but sometimes at a typical location (chordoma: sacrococcygeal region; adamantinoma: tibial shaft; malignant giant-cell tumor [GCT]: epi-metaphyseal expansion). Subsequent histological evaluation frequently reveals the (unexpected) diagnosis. For this reason, one section will focus on tumour mimics and differentiation from benign bone lesions. In this respect, some associated aspects of the well-known Lodwick (Madewell) classifications are discussed in order to highlight three very peculiar bone tumour-associated imaging phenomena (periosteal reactions, aneurysmatic bone cyst-like changes, peritumoral reactive zones).

Background: Sarcomas are rare, heterogeneous tumors of mesenchymal origin. Molecular imaging is crucial for diagnosis, staging, and therapy monitoring. ¹⁸F‑Fluorodeoxyglucose (¹⁸F‑FDG) positron-emission tomography/computed tomography (PET/CT) is a powerful technique for imaging high-grade soft tissue and bone sarcomas and supports staging, grading, biopsy targeting, and risk assessment using standardized criteria, e.g., European Organization for Treatment of Cancer (EORTC) criteria and PET Response Criteria in Solid Tumors (PERCIST).

New imaging methods and therapy: Fibroblast activation protein (FAP) is expressed at high concentrations in many sarcomas, often directly on the tumor cells themselves as well as on cancer-associated fibroblasts. FAP is therefore an attractive target for molecular imaging and therapy. ⁶⁸Ga-labeled FAP inhibitors (FAPIs) have shown higher uptake compared to ¹⁸F‑FDG across all sarcoma subtypes, including those with low ¹⁸F‑FDG avidity. FAPI-PET shows favorable tumor-background contrast and strong correlation with histopathological FAP expression. Prospective studies suggest that FAPI-PET may be superior to ¹⁸F‑FDG-PET in certain histological subtypes and may identify candidates for FAP-targeted radioligand therapy (RLT). Early clinical experience with radioligands such as ⁹⁰Y‑FAPI-46 demonstrates safety, feasibility, and disease control under FAP-RLT in more than half of evaluable patients with advanced metastatic sarcoma.

Outlook: Further prospective studies are needed to evaluate and establish the role of ¹⁸F‑FDG and FAPI-PET in personalized treatment strategies and sarcoma management.

Background: The changing working conditions in routine radiological reporting require the use of new methods, such as the implementation of artificial intelligence (AI) applications.

Research question: What practical possibilities currently exist to integrate AI applications into existing imaging reporting processes?

Material and methods: Assuming that the systems involved in the current reporting process, such as image management systems and various information systems, are to collaborate with AI applications, internationally recognized integration interfaces are required. The data exchanged also require standardized definitions to ensure interoperability across systems. Integration profiles as provided by Integrating the Healthcare Enterprise (IHE) offer a viable approach.

Results: The IHE profiles, such as Scheduled Workflow.b (SWF.b) and AI Workflow for Imaging (AIW-I) enable the combination of traditional imaging processes from patient admission up to AI-supported image reporting. The AI Result Assessment (AIRA) profile ensures legally compliant usage of AI Results. The AIR profile defines interoperable AI result formats that can be distributed within a defined reporting context via the integrated reporting applications (IRA) profile. The Interactive Multimedia Report (IMR) profile supports the persistence of final reports. Additionally, various data format specifications are currently evolving toward the Fast Healthcare Interoperability Resources (FHIR) implementation guides for the Image Diagnostic Report and the EU Imaging Study Report.

Discussion: The incorporation and use of AI in imaging processes are practically achievable using IHE profiles; however, integration based on structured data remains challenging and is currently reserved for larger institutions with the necessary IT resources.

Background: Abdominal and retroperitoneal sarcomas are rare but prognostically relevant tumors that pose significant diagnostic challenges due to their size and proximity to critical anatomical structures. Cross-sectional imaging is crucial for detection, characterization, staging, and treatment planning.

Objective: To present the current standards of cross-sectional imaging and to convey relevant aspects for radiological assessment based on established guidelines.

Methods: Summary of the morphological characteristics, recommendations for imaging and resectability criteria based on current guidelines and published literature.

Results: Magnetic resonance imaging (MRI) and computed tomography (CT) are indispensable for the assessment of abdominal and retroperitoneal sarcomas, especially with regard to organ and vessel relationships. MRI offers significant advantages over CT in the pelvis and for functional analysis. Typical patterns such as fat content, dedifferentiated areas, or infiltration support entity assessment and therapy planning.

Conclusion: Standardized, guideline-based imaging is essential for diagnosis, treatment planning, and follow-up care and should be performed in interdisciplinary sarcoma centers.

Background: The peroneal (fibular) nerve (PN) traverses the posterolateral aspect of the knee joint, placing it at risk during lateral meniscus (LM) repair, given its proximity to the popliteus tendon (PoT).

Objective: This study aimed to evaluate the risk of PN injury and define a safe anchor penetration angle during all-inside LM repair.

Materials and methods: A retrospective analysis was conducted using magnetic resonance imaging (MRI) scans of 327 individuals aged 18-60 years. The patellar tendon (PaT) and PoT widths were measured. The PN location relative to the PoT was determined. Distances from the PN to predefined medial and lateral reference lines across the PoT were calculated. The angular relationship between these lines and the transverse axis of the PaT was also analyzed for both anteromedial (AM) and anterolateral (AL) arthroscopic portals.

Results: The PN-to-PoT distance was found to be comparable for both portals. However, the PN was significantly farther from the lateral reference line in the AM portal and from the medial reference line in the AL portal. The safe upper limit for anchor insertion was approximately 65° from the AM portal and 88° from the AL portal.

Conclusion: Appropriate portal selection and anchor angle during all-inside LM repair can significantly reduce the risk of PN injury. The AL portal offers a broader safe insertion range and may therefore improve nerve protection.

Background: Radiology is integral to the multimodal diagnostic and treatment pathway of extremity soft tissue sarcomas in DGK-certified sarcoma centers (DGK: Deutsche Krebsgesellschaft, German Cancer Society), working in close interdisciplinary collaboration with sarcoma surgery, pathology, radiation oncology, and medical oncology.

Guideline-based imaging and triage: Treatment decisions rely on guideline- and recommendation-based imaging and histological confirmation by biopsy. When clinical warning signs (red flags) are present, radiological imaging is essential for triage and early referral to a sarcoma center. For local staging, magnetic resonance imaging (MRI) is the modality of choice. It provides crucial information for diagnosis, prognosis, and treatment within the sarcoma board and serves as the basis for adequate biopsy planning.

Morphological and technical pitfalls: Diagnostic pitfalls arise from overlapping MRI appearances, particularly within the lipomatous spectrum and in lesions with myxoid and cystic patterns. A further focus is on avoidable procedural biopsy errors, inadequate targeting, and an inadequate biopsy tract that is not amenable to en bloc resection or that contaminates additional compartments/joints or neurovascular structures.

Conclusion: The article outlines a risk-adapted diagnostic approach and provides practice-oriented principles for biopsy planning. It highlights typical problem MRI constellations to avoid misdiagnosis and underestimation of malignancy (grading), ultimately establishing optimal prerequisites for therapy.