Although this tumor is benign, it has the potential for malignancy or low-grade malignancy.

bubble_chart Pathological Changes

It often originates from the visceral pleura or interlobar pleura. It mostly presents as firm, gray-yellow nodules that are round or oval in shape. The surface is smooth, with grade I lobulation and an encapsulating membrane. The tumor nodules vary in size, ranging from a few millimeters to several centimeters in diameter, with larger ones potentially occupying one side of the thoracic cavity. The tumor has a broad contact surface with the pleura, protruding into the pleural cavity; a few have a short pedicle connecting to the pleura, allowing the mass to move when changing body position. The tumor tissue is composed of spindle cells and collagen fiber bundles, which may undergo hyaline degeneration and calcification.

bubble_chart Clinical Manifestations

The onset is insidious, often asymptomatic in the early stages, and is usually discovered during physical examinations or X-ray checks. When the tumor grows, it may cause compression symptoms, presenting as chest dull pain, dry cough, shortness of breath, and lack of strength. Pleural effusion is rare. Some patients may experience joint pain, clubbing of fingers, and hypoglycemia. X-ray findings show a solitary spherical or hemispherical mass shadow with uniform density and clear edges, sometimes with grade I lobulation.

bubble_chart Diagnosis

The clinical and radiographic manifestations lack specificity and are easily misdiagnosed as encapsulated effusion, subcutaneous nodules, lung cancer, chest wall and mediastinal tumors, etc. Percutaneous biopsy under the guidance of B-ultrasound or CT, or multiple biopsies under direct thoracoscopic vision, have diagnostic value.

Surgical resection is the only treatment method, and the resection should be as thorough as possible and performed as early as possible. Although this tumor is benign, it has the potential for malignancy or low-grade malignancy, and can recur or metastasize. Complete resection can often lead to a cure. Therefore, the prognosis is favorable.