Chest Wall Mass
A chest wall mass is an abnormal growth or lesion involving the structures that make up the wall of the chest, including the skin, fat, muscle, ribs, sternum, cartilage, blood vessels, and nerves. Chest wall masses can arise from any of these tissues and may be benign or malignant. Some are noticed as a visible or palpable lump, while others are discovered incidentally on imaging done for other reasons. CT and MRI are the primary imaging tests used to characterize a chest wall mass and guide further evaluation.
What is it?
The chest wall is the layered structure that surrounds and protects the contents of the chest. It includes the skin and underlying fat, several layers of muscle (including the pectoralis, intercostal, and serratus muscles), the ribs, the sternum, costal cartilage that connects the ribs to the sternum, blood vessels, and nerves. A chest wall mass is any abnormal growth or lesion in these tissues, and because there are so many different structures involved, the possible causes are wide-ranging.
Chest wall masses can be broadly grouped into benign and malignant categories, and into those arising from soft tissue versus bone. Benign soft-tissue masses include lipomas (collections of normal fat), epidermal inclusion cysts, hemangiomas, neurofibromas and schwannomas (nerve sheath tumors), and desmoid tumors (which are benign but locally aggressive). Benign bone lesions of the chest wall include enchondromas, osteochondromas, fibrous dysplasia, healing rib fractures, and infections such as osteomyelitis. Inflammatory and infectious causes include abscesses, costochondritis-related changes, and tuberculosis-related lesions in some regions.
Malignant chest wall masses include sarcomas arising from soft tissue or cartilage (such as chondrosarcoma and other sarcomas), Ewing sarcoma (more common in children and young adults), lymphoma involving the chest wall, primary or metastatic disease in the ribs or sternum, and direct extension of lung, pleural, or breast cancer into the chest wall. Metastatic disease from cancers such as breast, lung, kidney, and prostate is a particularly important cause to consider, especially in older adults and patients with a prior cancer history.
Symptoms depend on the size, location, growth rate, and type of mass. Many chest wall masses present as a palpable lump or visible swelling. Others cause localized pain or tenderness, which may be worse with movement, deep breathing, or pressure on the area. Skin changes such as redness, dimpling, or ulceration can occur with some lesions. Larger masses or those involving multiple ribs may limit chest expansion and breathing or compress nearby structures. Some chest wall masses cause no symptoms and are discovered incidentally on imaging done for unrelated reasons.
CT of the chest is the primary imaging test for evaluating a chest wall mass because it provides detailed information about size, location, density (including bone, fat, fluid, or calcification), involvement of ribs or sternum, and relationship to nearby structures such as the lung, pleura, and major vessels. MRI is particularly helpful for detailed soft-tissue characterization, evaluation of muscle and nerve involvement, and assessment of how deeply a lesion extends. Ultrasound is often useful for superficial masses and can also help guide biopsy. PET/CT may be used to evaluate metabolic activity and look for other sites of disease, especially when malignancy is suspected. In most cases, definitive diagnosis requires image-guided or surgical biopsy, which is planned carefully to avoid contaminating tissue planes when a sarcoma is possible.
Important to Know
Evaluation and treatment of a chest wall mass are highly individualized and depend on the suspected cause, the size and location of the mass, the patient’s symptoms, and overall health. Care is often coordinated by a multidisciplinary team that may include primary care, thoracic surgery, orthopedic oncology, plastic and reconstructive surgery, medical and radiation oncology, dermatology, and interventional radiology.
When imaging features clearly suggest a benign lesion—such as a typical lipoma or a stable, characteristic bone island—observation may be appropriate. When the diagnosis is uncertain or malignancy is suspected, biopsy is usually needed, and biopsy planning is important because the route chosen can affect future surgical options if a tumor needs to be removed.
Treatment ranges widely. Benign lesions causing symptoms or significant cosmetic concerns may be removed surgically. Infections are treated with antibiotics and, when needed, drainage or surgical debridement. Malignant chest wall tumors typically require a combination of treatments tailored to the specific diagnosis, often including surgery, radiation, and systemic therapy. Reconstruction of the chest wall may be needed after large resections to maintain stability and protect underlying organs.
Red flag symptoms include a rapidly growing lump, severe or worsening pain, pain that wakes the patient at night, skin breakdown or ulceration over a mass, significant unintended weight loss, persistent fever, or new neurological symptoms such as weakness or numbness. These warrant prompt medical evaluation.