Biatrial primary synovial sarcoma of the heart.

Synovial sarcomas that primarily arise from the heart and pericardium are extremely rare, especially the ones involving both sides of the heart. To date, few cases have been reviewed in the literature. Our patient was a 36-year-old man who presented with primary biatrial synovial sarcoma that also involved the tricuspid annulus, heart valves, and interatrial septum. The tumor was debulked to relieve the atrioventricular obstruction. Molecular analysis confirmed the diagnosis of synovial sarcoma with positive t (X;18) SYT-SSX gene fusion. The patient is currently receiving chemotherapy. From our review of the 20 cases thus far reported in the English-language medical literature, the tumor more frequently affects young male patients, and carries a poor prognosis. Early detection is difficult because of the aggressive nature of the tumor. Like other sarcomas, wide surgical resection remains the mainstay of therapy. Adjuvant radiation therapy for local recurrence and chemotherapy for control of systemic disease may have some beneficial effect on overall survival, but the benefit is likely limited.

Alpha-methylacyl-CoA racemase (AMACR/P504S) can distinguish hepatocellular carcinoma and dysplastic hepatocytes from benign nondysplastic hepatocytes.

Immunohistochemical staining with alpha-methylacyl-CoA racemase AMACR (P504S) has been described in a number of normal tissues and was found to be useful for detecting malignancies including hepatocellular carcinoma (HCC). Our aim was to determine whether AMACR is differentially expressed in benign nondysplastic liver tissue, hepatocellular dysplasia, and HCC. The study material consisted of paraffin blocks containing primary HCC and surrounding liver tissue from 20 patients who underwent hepatectomy at the time of liver transplantation. Immunohistochemical stains were performed with anti-AMACR by standard methods. Staining features were characterized on the basis of the pattern and distribution of reactivity. A positive AMACR immunostain was defined as either finely stippled or coarsely granular in pattern, in a diffuse or parabasal cytoplasmic distribution. A negative AMACR immunostain was defined as absence of reactivity. Anti-AMACR immunostains were positive in malignant, dysplastic, and benign nondyplastic hepatocytes in all cases. The staining pattern was the same in malignant and dysplastic hepatocytes. It consisted of coarsely granular reactivity in a parabasal or diffuse cytoplasmic distribution. In contrast, benign nondysplastic hepatocytes were distinguished by weak, finely stippled diffuse cytoplasmic staining. Malignant and dysplastic hepatocytes showed an identical pattern of immunostaining for AMACR that was distinct from benign hepatocytes. Prospective studies are needed to determine whether staining for AMACR can distinguish HCC or dysplasia in cytologic and small histologic specimens.

Secondary intracerebral blastomycosis with giant yeast forms.

Secondary central nervous system (CNS) blastomycosis is an unusual manifestation of blastomycosis. We report a case of recurrent intracerebral blastomycosis that presented histopathologically with giant yeast-like cells and multinucleation that mimicked Coccidioides immitis. The yeast forms of Blastomyces dermatitidis usually range in size from 8 to 20 microm in diameter. Large or giant yeast forms (20-40 microm) are rare. The four cases previously reported in the literature involving giant yeast cell forms of B. dermatitidis are reviewed here. Intracerebral blastomycosis should be suspected in patients with signs and symptoms of CNS lesions and histories of primary blastomycosis, or treatment with corticosteroids, or comprised immune systems. The diagnosis should be confirmed by culture which presents typical biphasic microbiologic features.

Fine-needle aspiration biopsy of cystic pleomorphic adenoma with adnexa-like differentiation mimicking mucoepidermoid carcinoma: a case report.

Although pleomorphic adenomas (PAs) usually can be diagnosed very accurately with fine-needle aspiration biopsy (FNAB), even this common salivary gland neoplasm can be diagnostically challenging and cause pitfalls in cytodiagnosis. In particular, the presence of either cystic changes or squamous, mucinous, or sebaceous metaplasia can lead to a false positive diagnosis of mucoepidermoid carcinoma (MEC). Here, we present a case of a 70-yr-old man with an asymptomatic left deep lobe parotid mass for which CT-guided FNAB was performed. The FNAB cytology revealed cohesive clusters of squamous epithelial cells, sebaceous cells, oncocytes, macrophages, and rare myoepithelial cells. Characteristic metachromatic fibrillar chondromyxoid stroma, which usually is seen in PAs, was not seen in the aspirate. Although cytodiagnosis of PAs was suggested based on the presence of other cellular components, resection was recommended. The subsequent parotidectomy specimen revealed an encapsulated cystic PA with mixed appendageal differentiation including areas of squamous, mucinous, sebaceous, and oncocytic metaplasia. Chondromyxoid stroma was only focally present. Presence of squamous, mucinous, and/or sebaceous metaplasia, especially in the absence of chondromyxoid stroma, presents the potential for misinterpretation of the FNAB as indicative of malignancy in general and MEC in particular.