Primary Mucinous Carcinoma of the Thyroid: A Case Report, Literature Review, and Immunohistochemistry Summary.

Introduction: Primary mucinous carcinoma of the thyroid is an exceedingly rare malignancy that is histologically similar to mucinous carcinoma of other sites. Accurate diagnosis is a challenging yet crucial component of clinical management for both patients and our understanding of this rare disease. Case Presentation: We report the case of a 69-year-old male patient with primary mucinous carcinoma of the thyroid. Microscopic examination of a biopsy specimen showed fibrous tissue, which was extensively and irregularly infiltrated by a cytologically malignant epithelial neoplasm showing glandular differentiation with mucin production. Immunohistochemistry demonstrated that tumor cells were positive for TTF1, thyroglobulin, CK7, and PAX8. Co-expression of TTF1 and PAX8 is most commonly seen in thyroid tumors. These findings support our diagnosis of mucinous carcinoma of thyroid origin, which is rare and highly aggressive. Conclusion: In this report, we present the only documented case of primary mucinous carcinoma of the thyroid reported in the United States in the last decade. The diagnosis of primary mucinous carcinoma of the thyroid can be challenging. Therefore, we discuss and detail the clinicopathologic tumor profile and provide more current, detailed histological criteria to assist in the diagnosis of this rare disease.

Endobronchial Ultrasound Diagnosis of a Malignant Superior Vena Cava Tumor Thrombus Extending Into the Right Atrium: An Unusual Cause of Recurrent Syncope.

The superior vena cava (SVC) is mainly responsible for the return of blood flow from the head, upper limbs, and neck into the right atrium. The large vein can be subject to extrinsic tumor compression and invasive intraluminal tumors-metastatic and mediastinal tumors that can lead to complete or partial occlusion. SVC occlusion can also result from chronic inflammation or scarring of the vessel iatrogenically by pacemaker wires or venous access ports used for chemotherapy, long-term antibiotics, or hemodialysis. Patients with SVC occlusion present with a constellation of clinical abnormalities that make up SVC syndrome. SVC syndrome includes varying degrees of facial fullness, neck and upper extremity swelling, dyspnea, and classically dilated collateral veins in the upper chest. Very rarely do patients present with syncope, hoarseness, dysphagia, or acute encephalopathy. The diagnosis of SVC syndrome is best established on imaging such as CT Chest with contrast; however, on rare occasions, it can be discovered by endobronchial ultrasound. We present an unusual presentation of SVC syndrome- primarily presenting as frequent syncopal episodes- diagnosed via endobronchial ultrasound.

Male breast disease: pictorial review with radiologic-pathologic correlation.

The male breast is susceptible to many of the same pathologic processes as the female breast. Many of these conditions have mammographic, ultrasonographic (US), and magnetic resonance imaging findings that allow differentiation between clearly benign conditions and those that require biopsy. Gynecomastia is the most common abnormality of the male breast and has characteristic imaging features that usually allow differentiation from malignancy. Mammography is the initial imaging modality for a clinically suspicious mass. A palpable mass that is occult or incompletely imaged at mammography mandates targeted US. Suspicious or indeterminate masses require biopsy, which can usually be performed with US guidance. Approximately 0.7% of breast cancers occur in men. Men with breast cancer often present at a more advanced stage than do women owing to a delay in diagnosis. Benign breast neoplasms that may occur in men include angiolipoma, schwannoma, intraductal papilloma, and lipoma. Benign nonneoplastic entities that may occur in the male breast include intramammary lymph node, sebaceous cyst, diabetic mastopathy, hematoma, fat necrosis, subareolar abscess, breast augmentation, venous malformation, secondary syphilis, and nodular fasciitis. Familiarity with the salient features of the classic benign male breast conditions will allow accurate imaging interpretation and avoid unnecessary and often invasive treatment. © RSNA, 2013.