Can a CT scan miss a thymoma?

Can a CT scan miss a thymoma?

The diagnostic accuracy of MRI is superior to CT in detecting thymomas, thymic cysts or thymic hyperplasia and that of CT and MRI is still unclear in differentiating thymic carcinomas and lymphomas/germ cell tumors and mere image analysis is insufficient for accurate diagnosis of thymic masses.

What is a cystic thymoma?

Thymic cysts are rare lesions located along the anatomical course of the third pharyngeal pouch. While most of the cases represent congenital cysts, they may also be related to neoplasms.

Can thymus be seen on CT scan?

Cystic changes in the thymus with or without calcification are seen at CT in about 20% of patients before they receive therapy (Figs 14, 15) (24,36). At MR imaging, thymic lymphomas typically have low signal intensity on T1-weighted images and variable signal intensity on T2-weighted images (24).

How do you evaluate thymoma?

Computed tomography is the imaging modality of choice for evaluating thymoma and can help distinguish thymoma from other anterior mediastinal abnormalities. Tumor stage and extent of resection are the most important prognostic factors.

How is CT thymoma diagnosed?

A CT scan of the chest is the most common test used to look for and evaluate a thymic tumor. Sometimes, a special dye called a contrast medium is given before the scan to provide better detail on the image. This dye can be injected into a person’s vein.

Can you have a thymoma without myasthenia gravis?

MG of some thymoma patients was not caused by thymoma, but by the paraneoplastic thymus. The prognosis of thymomas with MG is similar to that without MG. The main cause of death is myasthenia crisis for thymoma patients with MG and stage IV and/or type C for thymoma patients without MG.

Is a thymoma benign or malignant?

Thymoma is a rare tumor with a largely indolent growth pattern. It does, however, have malignant potential as a result of its ability to invade locally and metastasize regionally.

How common are thymic cysts?

Thymic cysts are a rare, benign anomaly and represent 1–3% of all mediastinal masses.

What does a thymoma feel like?

The most commonly associated condition with thymoma is myasthenia gravis, an autoimmune disease of the nerve-muscle junction that can manifest as weakness, fatigue, double vision, ptosis (drooping eyelids), and problems with swallowing.

Can you feel a swollen thymus gland?

Swelling in the face, neck, and upper chest, sometimes with a bluish color. Swelling of the visible veins in this part of the body. Headaches. Feeling dizzy or light-headed.

What are the symptoms of having a thymoma?

Thymoma and Thymic Carcinoma: Symptoms and Signs

• Persistent cough.
• Shortness of breath.
• Pain or pressure in the chest.
• Muscle weakness.
• Drooping eyelids.
• Double vision.
• Arm or facial swelling.
• Difficulty swallowing.

Can thymoma be misdiagnosed?

The main reason for misdiagnosis of intrathymic cyst as tiny thymoma was the CT value of intrathymic cyst was much higher than that of general cyst, even close to the density of thymoma, The CT attenuation was >20 HU in most intrathymic cysts cases, leading to the preoperative radiological diagnosis of thymoma (15).

What does a thymic carcinoma look like on a CT scan?

On CT scans, thymic epithelial tumors usually appear as homogeneous, oval, rounded or lobulated soft-tissue masses in the anterior mediastinum (,Fig 5,) (,18). In cases of invasive thymoma or thymic carcinoma, invasion of the mediastinal fat or adjacent structures as well as pleural seeding may be seen.

Can a CT scan detect an enlarged thymus?

CT is the study of choice in detecting enlarged thymus in patients with myasthenia gravis Small tumors may show homogeneous enhancement; larger tumors are usually heterogeneous Larger tumors especially may show cystic areas and necrosis

Can a CT scan predict the prognosis of thymic neoplasm?

Although calcifications are most commonly seen in more malignant types of thymic neoplasm, individually they are not considered a discriminatory finding. Of interest, CT findings can predict histology as described by the WHO classification scheme for thymic epithelial tumors and thus by extension prognosis 5-6 .

When does CT attenuation occur in a thymic cyst?

Some thymic cysts may have increased CT attenuation if hemorrhage or infection occurs as a complication. Curvilinear calcification of the cyst wall occurs in a small proportion of cases. According to one study, cysts had a mean attenuation value of around 23 HU and a maximal attenuation value of 58 HU 8,9.