Atypical MR appearance of Lhermitte-Duclos disease with contrast enhancement.

A case of surgically confirmed Lhermitte-Duclos disease demonstrated contrast enhancement on MR. Histologic examination verified corresponding increased vascularity in the molecular layer and adjacent leptomeninges.

Recurrent hemarthrosis associated with gout.

Gout commonly occurs as an acute arthritis. In a 64-year-old man, gout was associated with a proliferative hemosiderin-laden synovitis. The association of recurrent atraumatic hemarthrosis seems not to have been reported in the literature on gout.

Endometrial hyperplasia: value of endometrial thickness in ultrasonographic diagnosis and clinical significance.

The records of 90 patients with histologically proven endometrial hyperplasia (EH) were reviewed retrospectively. Eleven of these patients had pelvic ultrasound examinations available. These were compared to the pelvic ultrasound examinations of 19 patients with a histologically normal endometrium, available in 126 consecutive patients seen over the same period of time. Patients with EH had a mean endometrial thickness of 18.8 mm (range 8 mm to 45 mm) vs 5.4 mm (range 2 mm to 10 mm) in the control group. This difference in thickness was statistically significant (p much less than .01). The specificity and sensitivity of endometrial thickness in the diagnosis of EH were 100% and 81%, respectively, when 10 mm was taken as the upper limit of normal. Ultrasonographically demonstrable endometrial characteristics can differentiate EH from normal endometrium in a great majority of cases. The clinicopathological significance of EH is discussed.

Myxoid liposarcoma: magnetic resonance imaging appearances with clinical and histological correlation.

Myxoid liposarcoma is the most common type of liposarcoma. The magnetic resonance imaging (MRI) features of this tumor were evaluated and correlated with its clinical and histological features in seven patients to determine under what circumstances the tumor should be considered in differential diagnosis and why its signal intensity differs from those of lipoma and lipoma-like (lipoblastic) liposarcoma. In all patients the tumor presented in a lower extremity (5 thigh, 2 calf) as a painless, slowly growing mass which had been present for several months to several years. MRI examination revealed the tumors to be encapsulated, noninfiltrating, and usually septated. On T1-weighted sequences five of seven lesions (71%) showed lacy, amorphous, or linear foci of high signal within a low signal mass. These foci are believed to represent fat within the tumor and distinguish it from several other benign and malignant masses. If an indolent mass in a lower extremity demonstrates a predominantly low signal with a few amorphous or linear high signal foci on T1-weighted sequences, one should consider the possibility of myxoid liposarcoma even if it appears benign by all other criteria. Histologic evaluation showed that myxoid liposarcomas contain less than 10% mature fat, which accounts for their low signal on T1-weighted sequences in contrast to the high signal of lipomas and lipoblastic liposarcomas.

Lipid-rich metastatic balloon-cell melanoma: diagnosis by a multimodal approach to aspiration biopsy cytology.

Fine needle aspirates from one of multiple liver nodules revealed a large number of discohesive malignant cells with abundant vacuolated cytoplasm. The patient had had left eye enucleation the year before, for a melanoma with focal areas of clear cell change. Pap stained preparations from the liver FNA displayed well the nuclear features of balloon cell melanoma, including anisonucleosis, prominent nucleoli and intranuclear inclusions. Diff-Quik stain demonstrated best the cytoplasmic features such as distinct cell margins and finely dispersed and sharply delineated clear vacuoles. No pigmentation was noted but melanoma was suspected after the history prompted comparison with the enucleated specimen resected a year previously. A multimodal battery of ancillary methods including electron microscopy (EM) and immunocytochemistry (ICC) allowed the confirmation of balloon-cell melanoma, a rare variant not previously described in the eye. By EM, abundant lipids were identified along with melanin-containing structures resembling melanosomes. S-100 positivity along with negativity for epithelial, lymphohistiocyte and germ cell markers was compatible with melanoma. These findings are consistent with the view that cytologic detection of poorly cohesive, hypervacuolated cells does not exclude the possibility of melanoma. This rare example of a lipid-containing melanoma stresses the value of obtaining good clinical history, comparing FNAs to any pre-existing material and utilizing a multimodal approach to cytologic diagnosis in select cases.

Effect of bradykinin on feline gallbladder water transport and prostanoid formation.

Continuing evaluation of the pathophysiology of gallbladder disease has demonstrated significant relationships between gallbladder mucosal fluid transport, gallbladder inflammation, and prostanoid formation. Inflamed gallbladder mucosa secretes, rather than absorbs, fluid, a process associated with prostaglandin formation. Bradykinin has been previously implicated in the pathogenesis of cholecystitis and, in the intestine, bradykinin stimulates mucosal fluid secretion by a prostaglandin-mediated mechanism. Bradykinin was infused into the gallbladder lumen and administered intraarterially into the hepatic artery of perfused cat gallbladders. Both methods of bradykinin administration reversed the mucosal absorption present during control experiments as measured by concentration changes in a nonabsorbable marker. Perfusate and gallbladder tissue prostaglandin E concentrations were significantly increased by bradykinin when compared to control values. Concentrations of 6-keto PGF1 alpha in perfusate solutions and in gallbladder tissue were significantly increased, suggesting bradykinin increased prostacyclin formation. Bradykinin administration significantly increased inflammation, as evaluated by a histologic scoring system. Indomethacin was administered intravenously along with luminal perfusion of the gallbladder with bradykinin. Indomethacin significantly decreased gallbladder fluid secretion and prostanoid formation, but not histologic inflammation, when compared to values produced by bradykinin alone. An increase in systemic vascular and bile kinin concentrations produces gallbladder mucosal water secretion, a process which may be mediated by prostanoids. Histologic inflammation produced by bradykinin was not prevented by indomethacin.

Immunocytochemical evaluation of liver fine-needle aspirations.

A panel of antibodies to intermediate filaments, oncofetal antigens, and hepatocellular markers was tested on a prospective series of liver fine-needle aspirates to determine its utility in distinguishing hepatocellular carcinoma (HCC) from metastatic carcinomas. All fine-needle aspirations were assisted to ensure adequate cellularity, and were examined by a multimodal approach that included the preparation of B-5-formaldehyde-fixed cell blocks by the plasmathrombin technique. alpha-Fetoprotein was positive in four of eight HCCs, including the one example of combined hepatocellular-cholangiocarcinoma, but negative in the one case of pure cholangiocarcinoma and all cases of metastatic carcinoma. Carcinoembryonic antigen positivity was noted in four HCCs, a high proportion of metastatic adenocarcinomas, and occasional metastatic squamous cell carcinomas, but not in the one example of cholangiocarcinoma. Hepatitis B surface antigen was positive in only two cases of HCCs, but not in any metastatic tumors. Keratin and vimentin were positive, respectively, in four and three HCCs, and a variable proportion of metastatic carcinomas often coexpressed both antigens. Epithelial membrane antigen was positive in five of the eight HCCs. Our findings are consistent with the view that alpha-fetoprotein and hepatitis B surface antigen are reliable markers for HCC. However, none of the immunocytochemical markers reliably distinguished the primary site of metastatic carcinoma. The intensity of the immunostains in the fine-needle aspirations was comparable with that observed in tissues, but fragmentation of cell groups interfered with interpretation. Multiple passes and verification of the cellularity of the aspirates are crucial factors for the success of this approach to diagnosis.