Publications by authors named "Richard B Hessler"

Evaluation of rectal biopsies for ganglion cells is performed for patients suspected of having Hirschsprung disease. At times, identification of ganglion cells can be difficult, especially in newborns. To assist in diagnosis, frozen tissue can be collected for acetylcholinesterase histochemical staining.

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Introduction: Decreased expression of syndecan-1 has been reported in dysplasia and squamous cell carcinoma (SCCA) of the oral cavity and appears to correlate with decreasing histological differentiation and poor clinical outcome. Assays of syndecan-1 expression to date have utilized manual microscopic analysis with qualitative grading of immunohistochemical staining intensity, which may introduce observer bias. We evaluated syndecan-1 expression in dysplasia and squamous cell carcinoma (SCCA) of the oral cavity, using a novel automated cellular imaging system that incorporates both staining intensity as well as the percentage of positively stained cells to yield a quantitative value for syndecan-1 expression.

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The presence of small cell carcinoma within the submandibular gland is an uncommon clinical entity. However, other small round blue cell tumors are encountered in the head and neck with greater frequency. These include lymphoma, Ewing's sarcoma, melanoma, esthesioneuroblastoma, and neuroblastoma.

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Polymorphous low-grade adenocarcinoma (PLGA) of the parotid gland is rare. We describe a new case in which the patient underwent parotidectomy only to experience an extensive recurrence 2 years later. The recurrence was treated with radical surgical excision and radiation therapy, and the patient remained disease-free at 5 years of follow-up.

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The category of mixed glioneuronal tumors of the CNS is rapidly losing its definition as encompassing tumors composed of histologically distinct neuron variants and glia. We encountered five ependymomas with neuronal differentiation seen in two by histology, in two by immunohistochemistry alone, and in one by electron microscopy. Antibodies against GFAP, S-100 protein, neurofilament protein, chromogranin, synaptophysin, Neu-N, and EMA were applied.

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We present 8 examples of a neoplasm with features of both astrocytoma and ependymoma that may represent a distinct clinicopathologic entity. The cerebral hemispheric tumors occurred in patients that were 3, 4, 12, 14, 15, 26, 30, and 37 years of age. All presented with seizures that, with the exception of 2, began in childhood.

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Primary leiomyosarcoma of the central nervous system is rare and has been described both de novo and following temporally remote radiotherapy for a different unrelated malignancy. The authors report the case of a 42-year-old man in whom 60Co radiation treatment had been performed for an unknown primary mass in the brainstem 25 years previously. He presented with progressive neurological deterioration after undergoing many years of conservative therapy.

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Aspergillus fumigatus is a life-threatening and increasingly frequent pathogen of the immunocompromised. Like other filamentous fungi A. fumigatus grows in a highly polar manner, adding new cell wall to the apical region of hyphae.

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Objective And Importance: Composite pleomorphic xanthoastrocytoma (PXA)-ganglioglioma (GG) is a recently recognized, rare type of neoplasm that most commonly presents as a temporal seizure focus among male patients less than 30 years of age. This case represents the only reported suprasellar presentation, with the youngest reported age at diagnosis.

Clinical Presentation: We present the case of a 12-year-old boy with new-onset diplopia who was diagnosed as having a large suprasellar mass, which was presumptively designated a craniopharyngioma on the basis of its clinical and radiological appearance.

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We herein describe two cases of patients with epilepsy with occipital lobe cortical dysplasia who were studied with both MR spectroscopy and MR diffusion imaging in addition to conventional MR imaging. Greater diffusion abnormalities, as well as more marked decreases in N-acetylaspartate, were observed to occur in the patient harboring a low grade neoplasm within an area of cortical dysplasia than in the patient with cortical dysplasia alone.

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Sebaceous neoplasms arising in dermoid cysts of the ovary are exceedingly rare. We report a well-differentiated sebaceous carcinoma arising in a dermoid cyst in a 39-year-old female, the fourth such case in the literature.

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