Staging of Bone and Soft-tissue Sarcomas

Abstract

The purpose of staging in orthopaedic oncology is to provide a framework for classifying tumors based on their risk of local recurrence and distant metastasis to guide treatment decisions. Two separate systems are commonly used to categorize bone and soft-tissue sarcomas. The Musculoskeletal Tumor Society system for bone sarcomas and the Enneking system for soft-tissue sarcomas are the original staging systems developed by orthopaedic surgeons. The American Joint Committee on Cancer staging systems for bone and soft-tissue sarcomas are periodically updated based on new data, and they are currently on their eighth edition.

Atualização no estadiamento dos sarcomas ósseos e das partes moles

“…Malignant cells, however, tend to extend themselves beyond these limits; if this occurs, but the tumor remains confined to a given anatomical compartment, the lesion is deemed extracapsular and intracompartmental; if the lesion invades an adjacent compartment, it is classified as extracompartmental. 18 The multiplanar assessment and soft tissue enhancement provided by magnetic resonance imaging (MRI) or, if this modality is contraindicated or unavailable, 8,11 computed tomography (CT) with contrast media, made these imaging tests indispensable to local staging 19 ; occasionally, MRI and CT can be requested together, as they provide additional information that helps delineating the lesions under study. 17 It is worth mentioning that these tests must be performed before biopsy to avoid artifacts interfering with image interpretation.…”

“…15,18 It is mandatory to image the entire affected anatomical segment (whole bone) to define intramedullary involvement extension and identify eventual discontinuous bone tumors (skip metastasis), which presence has important prognostic implications. 6,11,14,15,20 The choice for MRI or CT in bone sarcoma evaluation may be based on radiographic findings. In cases with cortical destruction and extracompartmental tumor, MRI is the preferred modality because it provides excellent soft tissue enhancement and it is better in determining extraosseous tumoral extension compared with CT. 19 Magnetic resonance imaging allows more accurate staging due to its multiplanar (sagittal, coronal, axial and oblique) imaging ability and the lack of CTassociated beam hardening artifacts from cortical bone.…”

“…5 Several systems have been described to stage primary malignant tumors of musculoskeletal system. [3][4][5][6][7][8][9][10][11][12] However, the system proposed by William F. Enneking et al and adopted by the Musculoskeletal Tumor Society (MSTS) 6 and the system developed by the American Joint Committee on Cancer (AJCC) 8,9 are the most used in the clinical practice. The present paper aims to update the reader on bone and soft tissue sarcomas staging, using the Enneking/MSTS system 6 and the TNM classification (AJCC), in its 8 th edition (2017).…”

Brazilian consensus on the diagnosis and treatment of extremities soft tissue sarcomas

“…Conversely, tumors greater than 5.0 cm, deep in relation to the fascia, from intermediate‐ to high‐grade, should be staged with chest CT 21 (IIIA). Abdominal and pelvic CT should be requested in cases of high‐grade myxoid liposarcoma, leiomyosarcoma, epithelium sarcoma, and angiosarcoma 22 (VC). MRI can be considered in select cases of myxoid liposarcoma 23,24 (VB). Note : For the preparation of an adequate imaging report, the surgical staging of the tumor should be based on the TNM/AJCC 25 classification, and it must contain the following information on the MRI 20 : Size of the lesion, measured in three dimensions Location in relation to the fascia (superficial or deep); compartment, muscle involvement, extension through the fascia and into the skin Contours, well or poorly defined, and presence of satellite lesions Signal characteristics, suggesting fat, cystic, or solid lesion Signal characteristics, suggesting myxoid or hemosiderin tissue Description of the presence of peritumoral edema; neurovascular involvement (proximity, contact, partial, or complete involvement, incarceration); bone involvement: proximity or invasion (cortex and marrow); lymph node involvement; joint extension (capsule, joint space); and the prominence of intratumor veins (presurgical embolization). There is no consensus on PET‐CT. This diagnostic method appears to be useful in staging, prognosis, grading, and determining the response to chemotherapy 20,26 .…”

“…Abdominal and pelvic CT should be requested in cases of high‐grade myxoid liposarcoma, leiomyosarcoma, epithelium sarcoma, and angiosarcoma 22 (VC). MRI can be considered in select cases of myxoid liposarcoma 23,24 (VB).…”