Signet-ring squamous cell carcinoma.

Among carcinomas, signet-ring morphologic characteristics have been regarded as pathognomonic of adenocarcinoma. This report presents the case of a poorly differentiated cutaneous squamous cell carcinoma with a monodispersed, invasive signet-ring component. Kreyberg stains had negative results for mucin. Immunohistochemical analysis demonstrated that concentric rings in the signet-ring cells were composed of keratin. To the best of the authors' knowledge, this is the first report of signet-ring squamous cell carcinoma. Another feature that bears emphasis is that this squamous cell carcinoma led to the death of the patient, even though it originated in a field of actinic keratosis.

Spinal cord ischemia: an evaluation of pharmacologic agents in minimizing paraplegia after aortic occlusion.

Superoxide dismutase (SOD), barbiturates, and hypothermic crystalloid were evaluated for their effectiveness in minimizing ischemic damage to the spinal cord at 40 minutes of aortic occlusion. Forty-two dogs underwent proximal and distal thoracic aortic occlusion for 40 minutes with infusion of test agents into the occluded segment. The dogs were divided into six groups. Group 1 (n = 6) served as control. Group 2 (n = 6) received hypothermic crystalloid. Group 3 (n = 6) animals received thiopental. Group 4 (n = 7) received SOD. Group 5 (n = 9) received hypothermic crystalloid and thiopental. Group 6 (n = 8) received hypothermic crystalloid, thiopental and SOD. The animals were observed for neurologic deficit for 72 hours. In group 1, six of six dogs showed complete paralysis. Five of six dogs from group 2, five of six dogs from group 3, and five of seven dogs from group 4 showed complete paraplegia. The remaining dogs in these groups showed varying degrees of recovery. Four of nine dogs in group 5 had complete paraplegia, three dogs showed varying degrees of recovery, and two dogs had no neurologic deficit. In group 6, one dog had complete paraplegia, three had partial recovery, and four had no neurologic deficit. Group 6 was the only group that showed significantly less late neurologic impairment than the control group. We concluded that although cold perfusion, barbiturates, and SOD are not protective when used alone, they are effective when all are used in combination. The combination of cold perfusion, barbiturates, and SOD significantly decreases neurologic deficit after 40 minutes of aortic occlusion.

Benign glandular inclusions in parotid nerve.

Benign salivary ductular and acinar structures were demonstrated within an enlarged, disorderly intraparotid nerve in association with a mucoepidermoid carcinoma that did not, itself, manifest perineural invasion. Salivary gland can thus be added to the growing list of tissues in which "perineural invasion" by noncancerous epithelium has been observed. The proliferative features of the neural tissue in this case support the notion that neural elements may play an active role in the establishment of intimate neural-epithelial relationships. The mechanism for this phenomenon in the present case is postulated to be proliferation and ingrowth of the nerve tissue, possibly mediated by nerve growth factor or some related substance.

MR imaging of a spinal teratoma.

A benign intradural teratoma of the lumbar spine was studied with myelography, CT, magnetic resonance imaging, and histologic correlation. The tumor was composed of three portions (adipose tissue, neurofibrous tissue containing a large duct, and a keratinous cyst). Computed tomography distinguished the fat and the solid tissue from surrounding CSF but failed to differentiate the keratinous component of the mass. Magnetic resonance adequately demonstrated all three main components of the tumor.

Patterns of edema in tumors vs. infarcts: visualization of white matter pathways.

The computed tomographic (CT) scans of 339 patients with recent nonhemorrhagic cerebral infarct and 155 patients with supratentorial tumors were reviewed to evaluate the appearance of cerebral edema. White matter pathway edema characterized the CT pattern in 106 (68%) of the 155 tumor cases. In these 106 cases, there were 143 tumors, with edema in the arcuate white matter (73%), the external capsule (33%), the internal capsule (12%) and the corpus callosum (14%). In contrast, only four of the 339 cases of infarct had edema in the white matter pathways. In addition, 260 (77%) of the infarct cases had edema in both gray and white matter and 98% had at least gray matter involvement, while only two of the tumor cases had any gray matter edema. White matter pathway involvement with respect to tumor site is useful in differentiating tumor and infarct edema.

Limb malformations following maternal use of haloperidol.

A second case of severe limb malformations was observed following maternal use of haloperidol early in the first trimester of pregnancy. Haloperidol is teratogenic in mice, and may be teratogenic in humans.