A myxoma is a non-cancerous growth developing from connective tissue. These tumors are benign, meaning they do not spread like malignant cancers. Myxomas can arise in various locations, potentially affecting different organs and tissues. Their presence can lead to health concerns depending on size and location.
Understanding Myxomas
Myxomas are mesenchymal tumors characterized by their soft, gelatinous texture. Histologically, they contain scattered, star-shaped (stellate) cells within a loose, mucus-rich (myxoid) matrix.
While myxomas can occur in various parts of the body, they are most frequently found within the heart. Cardiac myxomas represent the most common primary tumor originating in the heart in adults. Approximately 75% of cardiac myxomas develop in the left atrium, often attached to the wall separating the heart’s upper chambers.
Myxomas can also be found in the skin (cutaneous myxomas) and within soft tissues (intramuscular myxomas). Cutaneous myxomas typically appear as small, flesh-colored nodules on the face, trunk, or extremities. Intramuscular myxomas usually occur in large muscles, such as those in the thigh, shoulder, buttock, and upper arm.
Recognizing Myxoma Symptoms
Myxoma symptoms vary considerably, depending on the tumor’s location, size, and whether it obstructs normal bodily functions. Many myxomas, especially when small, may not cause noticeable symptoms and are discovered incidentally during medical imaging. When symptoms do occur, they often relate to the tumor’s interference with surrounding structures.
Cardiac myxomas can lead to a range of symptoms due to their position within the heart. They might cause shortness of breath, particularly with activity or when lying flat, and fainting spells or dizziness. These symptoms can arise if the tumor partially blocks blood flow through a heart valve.
Fragments of a cardiac myxoma can break off and travel through the bloodstream, leading to an embolism. Depending on where these fragments travel, they can cause serious complications such as a stroke if they reach the brain, or blockages in other parts of the body like the limbs or lungs. Constitutional symptoms, such as fatigue, fever, or unexplained weight loss, are also reported in some individuals with cardiac myxomas.
Cutaneous myxomas often present as slow-growing, painless lumps beneath the skin. While generally not causing significant discomfort, they can sometimes be tender. Intramuscular myxomas typically manifest as a painless, slow-growing mass within a muscle. However, if they press on nerves or grow large, they might cause localized swelling or pain.
Diagnostic Process
Diagnosis typically begins with a physical examination and a review of medical history, especially if symptoms are reported. If a myxoma is suspected, imaging studies are used to visualize the tumor and its characteristics.
For myxomas within the heart, echocardiography is a primary diagnostic tool. This ultrasound technique provides clear images of the heart’s chambers, valves, and any abnormal growths, allowing assessment of the tumor’s size, shape, mobility, and attachment point. Transesophageal echocardiography, where the ultrasound probe is guided down the throat, offers more detailed views.
Myxomas in other areas, such as soft tissues or bone, are commonly evaluated using Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scans. MRI is useful due to its excellent soft-tissue resolution, helping characterize the tumor’s composition and relationship to surrounding structures. CT scans offer rapid imaging and determine the tumor’s exact location.
A definitive diagnosis usually requires a biopsy, where a small tissue sample is removed for microscopic examination. This pathological analysis confirms the presence of myxoma cells and differentiates it from other conditions, including malignant tumors. While imaging provides strong indications, biopsy remains the gold standard for confirmation.
Management and Outlook
Surgical removal is the primary and often curative treatment for most myxomas, regardless of location. Though benign, their presence can lead to complications such as blood flow obstruction, especially in the heart, or detachment of tumor fragments causing embolisms. Prompt surgical intervention is recommended to prevent these serious events.
The surgical procedure involves completely excising the myxoma, along with a small margin of surrounding healthy tissue, to minimize recurrence. For cardiac myxomas, this typically requires open-heart surgery, often utilizing a heart-lung bypass machine. Surgical techniques are adapted for myxomas in other locations to ensure complete removal while preserving function.
Following successful surgical removal, the outlook for individuals with myxomas is generally favorable. The recurrence rate for sporadic myxomas is low, typically ranging from 1% to 5%. However, recurrence can be higher, around 12% to 22%, in cases associated with genetic syndromes like Carney complex, or in younger patients.
Regular follow-up appointments, often including echocardiograms for cardiac myxomas, are important to monitor for tumor regrowth, particularly within the first few years after surgery. This ongoing monitoring helps ensure early detection and management of any recurrences.