Benign neoplasms
These tumors are relatively common and exhibit characteristic radiological patterns that allow distinguishing them from aggressive processes.
- Neurilemmomas (schwannomas) (Neurilemmomas): On MRI (T1-weighted images), the signal is isointense or hypointense, and on T2-weighted images, it is heterogeneously hyperintense. Strong contrast enhancement after gadolinium administration is characteristic. Areas of cystic degeneration and hemosiderin deposits may be identified within the structure.
- Neurofibromas (Neurofibromas): These are usually solitary nodules, although in patients with type 1 neurofibromatosis they present a diffuse plexiform pattern. On CT, they are hypodense lesions that, unlike schwannomas, show little to no contrast enhancement. On MRI (T2-weighted images), the "target sign" (target sign) is typical for them—a hyperintense rim with a dark center.
- Haemangiomas (Haemangiomas): Rare vascular malformations. Phleboliths (calcifications) and areas of adjacent bone remodeling are visible on radiographs and CT. MRI is the best modality for assessing their extent.
- Lymphangiomas (Lymphangiomas): Appear as cysts filled with low-protein fluid. They may contain internal septa.
- Elastofibroma dorsi (Elastofibroma dorsi): An unencapsulated crescent-shaped mass adjacent to the scapula. Considered a result of chronic microtrauma. Capable of FDG uptake on PET.
Primary malignant tumors
Primary soft tissue sarcomas of the chest wall are rare but require rapid and accurate staging.
- Undifferentiated pleomorphic sarcoma (UPS). Formerly called malignant fibrous histiocytoma. This is the most common soft tissue sarcoma in adults (mean age 55 years, more common in women). It grows from deep fascia. On MRI, the signal is extremely variable: if collagen predominates, the signal is low; if a myxoid component or hemorrhage is present, it is high on T2-weighted images.
- Angiosarcoma (Angiosarcoma). The primary vascular malignancy. Clinically presents as a large, painful mass prone to bleeding. Typical history includes development against the background of lymphedema after breast cancer treatment.
- Liposarcoma (Liposarcoma). The well-differentiated variant consists of 50–75% fat. Septa or contrast-enhancing nodules are identified internally.
- Fibrosarcoma (Fibrosarcoma). Forms large heterogeneous masses prone to aggressive direct invasion into the ribs, pleura, and lung parenchyma.
Secondary lesions and lymphoma
Secondary soft tissue tumors are significantly more common than primary ones. They can develop as a result of direct invasion (e.g., ingrowth of lung, breast, or mediastinal tumors) or as distant metastases.
Primary involvement of the chest wall by lymphoma is a rarity. As a rule, soft tissues are involved by contiguous spread in Hodgkin lymphoma or diffuse large B-cell lymphoma originating from the mediastinum or axillary lymph nodes. Such spread is considered a sign of poor prognosis. Lymphomas demonstrate intense radiopharmaceutical uptake on PET/CT, making this modality the primary one for disease staging.
Briefly: answers to topical questions
What are the histological types of liposarcomas, and what is their radiological structure?
There are four histological types of liposarcomas, whose radiological appearance is extremely variable and depends on the tissue composition.
- Myxoid (myxoid) — radiological appearance depends on the tumor composition.
- Well-differentiated (well-differentiated) — consists of 50–75% adipose tissue, contains internal structures (septa or soft tissue nodules) that enhance with contrast.
- Pleomorphic (pleomorphic) — a high-grade malignant tumor; the presence of macroscopic adipose tissue is least likely.
- Round cell (round cell) — a high-grade malignant tumor in which macroscopic fat is also rarely detected.
The spectrum of density and signal intensity varies from lesions with a predominance of fatty, liquid, and soft tissue components to tumors consisting exclusively of soft tissue. Contrast-enhanced CT may reveal a mass with areas of fatty and soft tissue density characterized by encasement of major peripheral vessels.
Class and exam questions
Neurilemmomas (schwannomas) usually show avid contrast enhancement. Neurofibromas, however, are hypodense lesions with minimal or absent contrast enhancement.
Neurilemmomas (schwannomas) usually show avid contrast enhancement. Neurofibromas, however, are hypodense lesions with minimal or absent contrast enhancement.
What is the "target sign"?
This is a characteristic MRI feature of neurofibroma on T2-weighted images, in which a hyperintense rim is seen surrounding a central low-signal zone.
Which imaging modality is best suited for visualizing chest wall hemangiomas?
MRI is the optimal modality. Despite artifacts from blood flow and hemorrhage, it is best for evaluating the true extent of the mass.
What else to study on this topic
- Chest wall bone tumors: Ewing sarcoma, chondrosarcoma, and osteosarcoma
- Benign rib lesions: fibrous dysplasia and osteochondroma
- Metastatic involvement of the clavicles and sternum
- Diagnostic imaging and types of pleural effusion
- Imaging features of pleural lesions on CT and radiography
Master the entire topic in the "Diagnostic Radiology" course
This is a summary. The course covers everything tested in classes and exams.
- Complete study guide on "Chest wall soft tissue tumors" and 2,199 more pages on the subject
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 10 video lessons on the subject
Other topics in the «Chest Radiology» section
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.