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The role of supraorbital nerve biopsy in cutaneous malignancies of the periocular region.

PURPOSE: To describe clinical situations in which a biopsy or resection of the supraorbital nerve may play a role in patients in whom perineural invasion secondary to cutaneous head and neck malignancies is suspected. METHODS: The clinical records of 230 patients with squamous cell carcinoma (SCCA) of the skin of the head and neck who were treated at the University of Texas M.D. Anderson Cancer Center between April 1994 and March 2001 were reviewed. Thirty-five patients were identified as having primary lesions on the forehead skin. Of these, 8 patients had microscopic or clinical evidence of perineural invasion. Four of these 8 patients had undergone a supraorbital nerve biopsy or resection in the course of their treatment. Although all 4 patients were classified as having had SCCA, 1 patient had a variant of undifferentiated SCCA that more appropriately should have been classified as lymphoepithelioma-like carcinoma. The clinical history was reviewed in each case. The median follow-up time for this cohort was 47 months (range, 24 to 72 months). RESULTS: The 4 cases reported here illustrate that a supraorbital nerve biopsy can help confirm the diagnosis of perineural invasion, identify the extent of tumor infiltration, and help in staging of particularly aggressive cutaneous malignancies of the periocular region. Access to the proximal (orbital) portion of the nerve can be accomplished through an anterior orbitotomy. CONCLUSIONS: A biopsy of the peripheral branches of the trigeminal nerve may be indicated as part of the staging or to confirm the diagnosis of perineural invasion in patients with SCCA or other locally aggressive cutaneous malignancies of the head and neck.

Aged↗

A xenograft nude mouse model for perineural invasion and recurrence in pancreatic cancer.

OBJECTIVE: Pancreatic cancer recurrence after initially "curative" resection is an unresolved clinical problem in the management of patients with this disease. Perineural invasion correlates with and might be partially responsible for tumor recurrence and poor survival. However, no adequate preclinical animal model is yet available to study this aspect of pancreatic cancer biology. METHODS: We modified our orthotopic xenograft model of pancreatic cancer in nude mice to develop a model for pancreatic cancer perineural invasion and recurrence. RESULTS: After initial orthotopic transplantation, complete surgical resection of MIA PaCa-2 (undifferentiated) and Capan-2 (well-differentiated) tumors at 4, 6, and 8 weeks was attempted. All animals that had undergone tumor resection survived the operation. Animals that had the MIA PaCa-2 tumor resected after 6 weeks developed recurrent pancreatic cancer with local invasion and distant metastasis. Histological evaluation revealed extensive invasion of retroperitoneal nerves by the cancer cells. CONCLUSION: Complete resection of orthotopically transplanted pancreatic cancer in nude mice leads to local tumor recurrence. This model may eventually prove valuable for studying the mechanisms of pancreatic cancer perineural invasion and recurrence.

Animals↗

Intraocular peripheral nerve sheath tumor in a dog.

A tumor within the right globe in a 9-year-old Shetland sheepdog was examined pathologically. The tumor was composed of spindle or oval cells arranged in interwoven bundles with intervening collagenous or mucinous matrices. Immunohistochemically, the tumor bound antibody directed to S-100 protein and vimentin, but not to desmin, actin smooth muscle, or neurofilament. Electron microscopy revealed that the tumor cells had poorly developed cytoplasmic processes, desmosomes between closely contiguous cells, and a discontinuous basement membrane-like material. Based on these findings, the tumor was diagnosed as a peripheral nerve sheath tumor (PNST) histologically. To the authors' knowledge, this is the first reported case of intraocular PNST in dogs.

Animals↗

Neutral glycosphingolipids and ceramide composition of ethylnitrosourea-induced rat neural tumors: accumulation of ceramide in tumors.

Experimental rat neural tumors in offspring were induced transplacentally by a single injection of a chemical carcinogen, ethylnitrosourea, 20 mg/kg body weight, in the tail vein of the mother. The neutral glycosphingolipid, sulfatide, and ceramide composition of the tumors and the normal tissues from which the tumors originated is described. The content of nonhydroxy fatty acid (NFA) and hydroxy fatty acid (HFA) containing ceramide in all the neural tumors so far examined was significantly increased compared with the corresponding normal neural tissue. Some 8 to 18 mol% of total neutral glycolipids was as ceramide in neurinomas, oligodendrogliomas, and meningiomas. Lactosylceramide in normal neural tissues was about 1 mol% of the total neutral glycosphingolipids. In various neural tumors lactosylceramide increased up to 8 mol%. NFA- and HFA-containing cerebrosides constitute 94-100% of the neutral glycosphingolipids in normal neural tissues. In various neural tumors the mol percent of cerebrosides was significantly reduced. A high performance liquid chromatographic method was modified to analyze simultaneously ceramides, cerebrosides, and higher neutral glycosphingolipids.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗

Perineurial cell tumor (perineurioma) with granular cells.

A form of benign cutaneous tumor with perineurioma findings and with the presence of associated granular cells is described. The two cases studied consisted of whorls made up of a high number of circumferentially arranged flattened cells, with perineurial characteristics, including bipolar cell processes, pinocytotic vesicles, a basal lamina, a positive immunoreactivity for EMA, and absence of immunostaining for S-100 protein. The granular cells, enclosed within the whorls, contained densely packed vesicles, particles with an apparently solid core, as well as membrane-limited vacuoles with disintegrating cellular organelles and electron-dense amorphous material. While failing to demonstrate any immunoreactivity for EMA, the granular cells showed positivity for S-100 protein, which supports their Schwann-cell origin. Due to its morphological and immunohistochemical characteristics, this peculiar form of tumor can be considered as a perineurioma with perineurial cell whorls and granular cell changes occurring in associated Schwann cells at the center of the whorls.

Adult↗

Cutaneous epithelioid schwannomas: a rare variant of a benign peripheral nerve sheath tumor.

Although benign epithelioid peripheral nerve sheath tumors have been described, they are rare, and benign epithelioid schwannomas have not yet been established as a specific histologic variant. We present four cases of tumors which we believe would meet criteria to be classified as benign epithelioid schwannomas. Biopsy specimens obtained from four different patients were examined with routine and immunohistochemical staining. All the tumors were well-circumscribed lesions that were surrounded by a capsule containing EMA-positive cells. The cellular component was composed of epithelioid cells, in which there was a lack of mitotic activity. Immunohistochemical studies showed the tumor cells were S-100 protein and Leu 7 positive and HMB-45 negative. In addition, type IV collagen encircled individual cells within the tumor, indicating a continuous basal lamina. We report a group of cutaneous epithelioid schwannomas. Although the presence of such tumors is not unexpected, this diagnosis may not be initially considered because of this rare cytologic feature.

Adult↗

Magnetic resonance imaging and ultrasonography in the diagnosis of a malignant peripheral nerve sheath tumor in a dog.

A 9-year-old male neutered mixed breed dog had a two-month history of progressive left thoracic limb lameness. There was electromyographic evidence of denervation potentials in all muscles of this limb. In magnetic resonance images a multilobulated, hyperintense mass was visible caudal to the middiaphysis of the left humerus on T-2 weighted images. The mass, which was isointense with surrounding tissue on T1 weighted images, extended proximally towards the brachial plexus. The mass was also visible as a fusiform structure of mixed echogenicity sonographically, although fine-needle aspiration performed at this time was nondiagnostic. A malignant peripheral nerve sheath tumor was diagnosed histopathologically.

Action Potentials↗

Metastasizing ependymoma of the cauda equina.

A case of metastasizing ependymoma is described, only the second in the British literature. The tumour, which arose in the cauda equina, spread to humerus and pleura over a period of 32 years. It is postulated that, in common with most of the previously reported cases, dissemination was a direct consequence of either surgical intervention or radiotherapy since neither the primary tumour nor its metastases shows any of the conventional morphological criteria of malignancy. The literature of similar cases is briefly reviewed.

Adult↗

Low grade malignant peripheral nerve sheath tumour: varied cytological and histological patterns.

BACKGROUND: A small number of malignant peripheral nerve sheath tumours (MPNSTs) are low grade, and the nature of these low grade tumours has never been systematically assessed. AIMS: To describe the clinicopathological, immunohistochemical, and ultrastructural features of low grade MPNST and to discuss the main differential diagnoses. METHODS: Four cases of low grade MPNST were studied, including one coexistent with neurofibromatosis type 1. The tumours were analysed with respect to nuclear atypia, cellularity, nuclear enlargement, hyperchromasia, mitotic rate, and necrosis. Immunohistochemistry was performed by standard techniques, and an ultrastructural study was performed on one tumour. RESULTS: The ages of the patients ranged from 32 to 72 years (mean, 58). Two were male and two were female. Three tumours occurred in the deep tissue, including one in the retroperitoneum, and one was located in the dermal and subcutaneous tissue. The maximum diameters of the tumours ranged from 3.5 to 8.0 cm. Microscopically, all tumours showed moderate hypercellularity, an increased nuclear to cytoplasmic ratio, and hyperchromasia, but exhibited varied growth patterns, including those that were atypical neurofibroma-like, low grade fibromyxoid sarcoma-like, low grade epithelioid, and haemangiopericytoma-like. All tumours showed immunoreactivity for S-100 protein and vimentin. CONCLUSIONS: These findings suggest that careful clinical and histological evaluation, along with S-100 protein immunostaining, are essential for the accurate diagnosis of low grade MPNST.

Adult↗

Meningeal carcinomatosis: treatment with intrathecal methotrexate.

A case of bronchogenic carcinoma with meningeal carcinomatosis is reported. Intrathecal chemotherapy with twice weekly methotrexate was effective in clearing the cerebrospinal fluid abnormalities, pathologic evidence of meningeal disease, and all of the clinical manifestations, with the exception of spinal root symptoms and signs associated with tumor infiltration of nerve roots at autopsy. The role of radiotherapy as an adjunct to chemotherapy in the treatment of this condition is discussed.

Adenocarcinoma↗

Effect of disulfiram on acetoxymethyl-methyl-nitrosamine-induced tumors in rats.

Male Sprague-Dawley rats were given 10 weekly intravenous injections of acetoxymethyl-methylnitrosamine (AMMN = N-nitroso-acetoxymethyl-methylamine). One group was also treated with disulfiram (DSF) by gavage twice daily five times per week. DSF markedly reduced the rate of heart and lung tumors but not of tumors at other organ sites. In animals treated with the combination of DSF and AMMN a significant incidence of neurogenic tumors was observed. No neurogenic neoplasms occurred in animals treated with AMMN alone. During the observation period DSF showed no carcinogenic potential.

Adenocarcinoma↗