Utilization of peripherin and S-100 immunohistochemistry in the diagnosis of Hirschsprung disease.

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. At our institution, we developed a protocol using peripherin and S-100 immunostaining as an adjunct to hematoxylin and eosin (H&E) for the identification of ganglion cells. Further, at the time of frozen section, we performed Diff Quik staining to highlight ganglion cells. One hundred and thirty eight rectal biopsies submitted for evaluation of Hirschsprung disease were compiled from the archives of the Medical College of Georgia from 2002 to 2009. Initial evaluation consisted of eight levels of H&E-stained slides and two unstained slides each for immunostaining with peripherin and S-100. If on initial evaluation, ganglion cells were not identified, additional H&E and peripherin immunostains were performed. Peripherin immunostaining was unequivocally identified in the cytoplasm of ganglion cells of patients at all ages. Of the 136 patients with diagnostic biopsies, 80% had ganglion cells. Of these, 93% of cases were diagnosed on the original eight levels. Twenty-seven cases were devoid of ganglion cells, and of these, 81% showed submucosal neural hypertrophy on S-100 staining. Twenty-six patients had confirmed aganglionic segments at the time of colonic resection. One patient had colostomy only. A total of 54 frozen sections were performed on 25 patients over this same period of time. Diff Quick staining was found to be very useful. In this study, our protocol proved to be very sensitive, specific, and efficient for the diagnosis of Hirschsprung disease.

Quantitative analysis of syndecan-1 expression in dysplasia and squamous cell carcinoma of the oral cavity.

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. MATERIALS AND METHODS: We performed a quantitative immunohistochemical analysis of syndecan-1 expression using an automated cellular image analysis system. We analyzed specimens from cases of mild dysplasia (N = 55), moderate dysplasia (N = 38), severe dysplasia (N = 25), carcinoma in situ (CIS) (N = 43), and SCCA of the oral cavity (N = 45), using normal mucosal epithelium (N = 21) as a positive control. The SCCA specimens were further subdivided by degree of differentiation. We retrospectively reviewed patient charts to identify tumor stage at diagnosis, recurrence, and disease-specific survival. RESULTS: Syndecan-1 expression was significantly greater in normal controls than in specimens of mild, moderate, or severe dysplasia, CIS, or invasive SCCA (P < .05). Syndecan-1 expression did not differ significantly among specimens of mild, moderate, or severe dysplasia, CIS or SCCA. There was no significant difference in syndecan-1 expression between specimens from patients with no evidence of disease at 3 years follow-up and patients with local, regional, or distant recurrence. CONCLUSIONS: Syndecan-1 expression does not appear to be useful as a marker of differentiation or as a prognostic indicator in dysplasia and SCCA of the oral cavity. The search for a suitable and reliable marker of biological aggressiveness is ongoing.

Small cell carcinoma of the submandibular gland: a rare small round blue cell tumor.

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. A basic knowledge of the immunohistochemical studies available to distinguish each these tumors from one another significantly improves the frequency of accurate and timely initial diagnosis. We report a case of small cell carcinoma of the submandibular gland and review the other common small round blue cell tumors that occur within the head and neck. We utilize an acronym, LEMONS, to organize our review and facilitate improved retention of the differential diagnosis for small round blue cell tumors of the head and neck.

Ependymomas with neuronal differentiation: a morphologic and immunohistochemical spectrum.

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. Ultrastructural studies were also performed. In addition, 33 randomly selected ependymomas of various histologic types were screened for these same antigens. Cases 1 and 2 were anaplastic and showed clearly defined neuropil islands or pale islands as in nodular desmoplastic medulloblastoma, respectively. The tumors affected a 16-year-old male and a 5-year-old female and involved the right frontoparietal lobe and fourth ventricle, respectively. The islands were positive for synaptophysin and Neu-N (cases 1 and 2), and chromogranin (case 1). Cases 3-5, as well as 7 of the 33 screened ependymomas, showed a suggestion of neuronal differentiation by immunohistochemistry alone, including immunoreactivity for Neu-N (n = 8), synaptophysin (n = 4), neurofilament protein (n = 4), and chromogranin (n = 2). Five tumors each were WHO grade II and III. Electron microscopy performed on the two cases with neuronal islands demonstrated microtubule bundles and dense core granules (case 1) and poorly differentiated cells with high nuclear/cytoplasmic ratios, with intermediate filament accumulation and rare cilia (case 2). Cases identified by immunohistochemistry or electron microscopy demonstrated dense core granules (n = 5) and aligned microtubules (n = 3). Neuronal differentiation occurs in ependymomas but is less frequently definitive (histologic, ultrastructural) than merely a limited immunohistochemical finding. The clinical significance of these observations is unknown but deserves further exploration.

Polymorphous low-grade adenocarcinoma of the parotid gland.

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. We also review the literature on primary parotid PLGA.

Monomorphous angiocentric glioma: a distinctive epileptogenic neoplasm with features of infiltrating astrocytoma and ependymoma.

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. Magnetic resonance imaging studies showed ill-defined, T2-hyperintense, generally noncontrast-enhancing lesions that, although centered on the cortex or amygdala, extended into the underlying white matter for a short distance. Histologically, the variably infiltrative tumors were distinctively angiocentric with well-developed perivascular pseudorosettes in some cases. Longitudinal and/or circumferential orientations of perivascular cells were common also. The cells were uniform in their cytologic features from case to case and were bipolar in all but one case. A glial nature was inferred from immunoreactivity for GFAP, and ependymal differentiation was suggested by positivity for EMA in three cases and ultrastructural features in one. Overall, the tumors were biologically indolent except for one that recurred and ultimately proved fatal.

The Aspergillus fumigatus cell wall is organized in domains that are remodelled during polarity establishment.

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. mAbs were raised against isolated A. fumigatus cell walls. Fifteen antibodies bound reproducibly to isolated cell walls in ELISAs and to the walls of intact cells in immunofluorescence experiments. Surprisingly, individual mAbs showed distinct patterns of localization. Six antibodies labelled exclusively conidial or basal regions, seven labelled apical regions and a single antibody labelled both basal and apical regions of hyphae. Ten antibodies did not label the walls adjacent to septa. In double labelling experiments with representative mAbs there was little or no overlap between epitopes recognized. These labelling patterns suggest that the wall is made up of basal and apical domains that differ in composition or organization and that the wall region flanking septa differs from other regions of the lateral wall. In time-course experiments of early A. fumigatus growth, mAb16C4 failed to label isotropically expanding cells and labelled emerging germ tubes and branches. The same mAb failed to label the Aspergillus nidulans swoC mutant, which is defective in polarity establishment. However, mAb16C4 did label the A. nidulans swoA mutant, which completes polarity establishment, but is defective in polarity maintenance. Thus, mAb16C4 appears to recognize a cell wall change that occurs during polarity establishment. In immunogold labelling and transmission electron microscopy (TEM) experiments, conidia, basal regions and apical regions of thin-sectioned cells labelled with mAb16C4. That only apical regions labelled in intact cells (immunofluorescence) while conidial, basal and apical regions labelled in thin-sectioned cells (TEM) suggests that the 16C4 epitope is present along the whole hypha, but is masked everywhere except the tip until polarity establishment. That is to say, some remodelling of the wall during polarity establishment exposes the 16C4 epitope. The 16C4 epitope was partially purified from A. fumigatus total protein by passage through hydrophobic interaction and anion-exchange columns. The resulting single ELISA-positive fraction showed relatively few bands by SDS-PAGE and silver staining and a strong band by Western blotting with the16C4 mAb. Sequencing of the fraction yielded a predicted peptide with a 6-amino acid exact match to a region of the Cat1 protein previously identified as an immunodominant A. fumigatus catalase that localizes to the cell wall and is secreted to the medium. Experiments are under way to determine if mAb16C4 recognizes Cat1 or another protein that co-purifies with Cat1.

Composite pleomorphic xanthoastrocytoma-ganglioglioma presenting as a suprasellar mass: case report.

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. INTERVENTION: Gross total resection of a well-encapsulated tumor with adjacent cysts was achieved, without postoperative neurological deficits. Frozen-section studies suggested pilocytic astrocytoma; however, the final histological diagnosis was composite PXA-GG. CONCLUSION: Composite PXA-GG, although extremely rare, may present as a pediatric suprasellar mass. The histopathological diagnosis is contingent on the demonstration of distinct coincident PXA and GG components. The prognosis after gross subtotal resection is likely favorable; however, long-term follow-up monitoring is indicated for these rare neoplasms.

Advanced MR imaging of cortical dysplasia with or without neoplasm: a report of two cases.

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.

Sebaceous carcinoma arising in a mature cystic teratoma of the ovary.

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.

Leiomyosarcomatous transformation of unknown pediatric primary brainstem lesion following radiotherapy. Case report.

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. A stereotactic biopsy sampling procedure was performed, and examination of the left cerebral pedunculopontine lesion revealed a spindle cell neoplasm. Histopathological and immunohistochemical examination of the tumor obtained from definitive resection suggested leiomyosarcomatous transformation of ganglioglioma.