Epidermal Growth Factor Receptor Expression in Spindle Cell Carcinomas of the Head and Neck

Spindle cell carcinoma (SpCC) is an uncommon head and neck squamous cell carcinoma (SCC) variant consisting of spindled and/or pleomorphic cells with epithelial differentiation. Epidermal growth factor receptor (EGFR) is expressed by >90 % of conventional SCC, and high level expression is associated with a poorer prognosis. Anti-EGFR therapies are commonly used to treat head and neck SCC. However, no studies have evaluated EGFR expression in SpCC. Cases of SpCC were retrieved from department files. The diagnosis required either a biphasic lesion with a squamous neoplastic component, or a purely spindle cell or pleomorphic tumor with immunohistochemical positivity for epithelial markers. EGFR immunohistochemistry was performed and was quantified in quartiles. Medical records were reviewed for clinical follow up information. EGFR was expressed in 21/30 (70 %) cases, including in the squamous component in 18/19 (95 %) and the spindle cell component in only 12/30 (40 %). Where the spindle cell component was positive, the intensity and distribution were lower than for the squamous component. Recurrent tumors were predominantly (80-90 %) of the spindle cell component, and had low (or absent) EGFR expression. Kaplan-Meier survival analysis showed no statistically significant differences in overall or disease free survival between the EGFR expressing and non-expressing groups (p = 0.414 and 0.19, respectively). SpCCs of the head and neck have a poor prognosis, and markedly reduced EGFR expression. EGFR-specific therapies may not be ideal for SpCC patients, which may lack EGFR expression, but further studies are needed.

Squamous cell carcinoma arising in recurrent respiratory papillomatosis with pulmonary involvement: emerging common pattern of clinical features and human papillomavirus serotype association

Squamous papillomas of the lung are an uncommon feature of recurrent respiratory papillomatosis, occurring in fewer than 1% of cases. We describe a 23-year-old patient with pulmonary papillomas who developed a fatal squamous cell carcinoma of the lung. PCR-based human papillomavirus (HPV) typing showed the presence of HPV 11 DNA in both benign papillomas and invasive carcinoma. A review of the literature reveals four reports of malignant transformation of juvenile-onset recurrent respiratory papillomatosis in which HPV typing was performed. Similar clinical features are noted in all of the reports; specifically, each case has arisen in a young adult man with a history of papillomatosis since childhood. In each of the cases, HPV 11 was identified in association with the squamous cell carcinoma. Although HPV 11 is uncommonly associated with the development of invasive carcinoma at other sites, these findings suggest that it is correlated with malignant transformation in the setting of juvenile-onset recurrent respiratory papillomatosis.

Laryngeal blastomycosis: a commonly missed diagnosis. Report of two cases and review of the literature

Blastomycosis is a relatively uncommon fungal disease that most commonly affects the lungs. Other organs may be involved, usually secondary to dissemination of the organism. Laryngeal blastomycosis may occur in isolation from active pulmonary disease. The signs, symptoms, clinical features, and pathological findings of laryngeal blastomycosis mimic those of squamous cell carcinoma. Misdiagnosis may result in inappropriate treatment with potential morbidity. Proper understanding of the clinical presentation and familiarity with the histopathologic features of this disease are therefore imperative. In this paper, we report 2 cases of laryngeal blastomycosis, 1 of which was misdiagnosed as squamous cell carcinoma, clinically and microscopically, with consequent radiotherapy and laryngectomy. In the other case, a clinical diagnosis of glottic squamous cell carcinoma was rendered. However, blastomycosis was identified in a biopsy specimen. We also review cases of isolated laryngeal blastomycosis that have been reported in the English-language literature during the last 80 years. A number of those cases were misdiagnosed clinically and microscopically as squamous cell carcinoma.

Cemento-ossifying fibroma and benign cementoblastoma

Cementum is a calcified dental tissue that covers the roots of teeth and is part of the periodontium. Its function is to help anchor the teeth in their sockets within the alveolar bone of the jaws. Two benign mesenchymal odontogenic tumors are uniquely distinguished by elaboration of cementum or cementum-like material: cemento-ossifying fibroma and benign cementoblastoma (true cementoma). Cemento-ossifying fibroma, which is also termed periodontoma, is characterized by production of cementum and bone in a fibrous stroma. It is a painless, slow-growing tumor usually detected in the third and fourth decade of life and is more common in women. The mandible is its site of predilection. Benign cementoblastoma is intimately associated with the roots of teeth, most commonly mandibular molars. It affects young patients, usually under the age of 20 years. Pain is a common symptom in addition to bone expansion. Benign cementoblastoma bears considerable histologic resemblance to osteoblastoma.

Tubulopapillary hidradenoma-like tumor of the mandible: clinicopathologic and immunohistochemical features

Tubulopapillary hidradenoma is a benign sweat gland tumor that appears as a well-defined, superficially located dermal nodule. It combines ductal as well as apocrine and eccrine glandular differentiation. Microscopically, the tumor is composed of tubular structures that characteristically show intraluminal non-villous papillary projections and a peripheral myoepithelial cell layer. A tumor that is histologically and immunohistochemically identical to tubulopapillary hidradenoma occurred in the mandible of a 73-year-old man and resulted in considerable diagnostic difficulty. The neoplasm developed in a mandibular cyst and recurred 5 years after initial enucleation. This is the first report of a central (intraosseous) sweat gland adenoma of the mandible. The differential diagnosis and possible histogenesis are discussed.

Clinical Correlations with Allelotype in Supraglottic Squamous Cancer

Frequent allelic loss at a genetically polymorphic locus in tumors is an established marker for the presence of a tumor suppressor gene in the neighboring chromosomal region. This technique can be used to identify novel tumor suppressor genes and to monitor their status before the cloning of the gene itself. We have used the polymerase chain reaction and microsatellite loci on all 39 nonacrocentric autosomal chromosomal arms to identify sites of frequent allelic loss in squamous cell carcinomas of the supraglottic larynx. Our allelotype identified seven chromosomal arms (3p, 5q, 8p, 9p, 9q, 13q, and 17p) likely to contain tumor suppressor genes frequently inactivated during squamous tumorigenesis in the larynx. We tested for associations between allelic losses on these chromosomal arms and the clinical and histopathologic features of these tumors. There were no correlations with either T or N classifications. Allelic loss on chromosomal arm 13q is significantly associated with a number of histopathologic features characteristic of poorly differentiated or histologically aggressive tumors. Allelic loss on this arm also exhibits statistical trends toward association with early tumor recurrence and poor survival. The association with survival was substantiated by a multivariate Cox proportional hazards model.

Clinical correlations with allelotype in supraglottic squamous cancer

Frequent allelic loss at a genetically polymorphic locus in tumors is an established marker for the presence of a tumor suppressor gene in the neighboring chromosomal region. This technique can be used to identify novel tumor suppressor genes and to monitor their status before the cloning of the gene itself. We have used the polymerase chain reaction and microsatellite loci on all 39 nonacrocentric autosomal chromosomal arms to identify sites of frequent allelic loss in squamous cell carcinomas of the supraglottic larynx. Our allelotype identified seven chromosomal arms (3p, 5q, 8p, 9p, 9q, 13q, and 17p) likely to contain tumor suppressor genes frequently inactivated during squamous tumorigenesis in the larynx. We tested for associations between allelic losses on these chromosomal arms and the clinical and histopathologic features of these tumors. There were no correlations with either T or N classifications. Allelic loss on chromosomal arm 13q is significantly associated with a number of histopathologic features characteristic of poorly differentiated or histologically aggressive tumors. Allelic loss on this arm also exhibits statistical trends toward association with early tumor recurrence and poor survival. The association with survival was substantiated by a multivariate Cox proportional hazards model.

Early membrane injury in lethally irradiated salivary gland cells

The early manifestations of radiation injury in salivary glands were investigated in the rat. The animals received a single X-ray dose in the range of 200-2000 rad to their neck area. Glandular changes during the first 24 hours were studied by light and electron microscopy and by measuring serum amylase activity. The amount of cell necrosis was quantitated and expressed as necrosis index (NI), Parotid NI and serum amylase activity 24 hours following irradiation were directly proportional to the X-ray dose. The submandibular gland cells were radioresistant and so were the mucous cells of the sublingual gland. The major increase in parotid acinar cell necrosis occurred between 12 and 24 hours after irradiation. However, more than 100 per cent increase in serum amylase level was detected prior to the onset of any significant cell necrosis. As early as two hours following irradiation signs of cell membrane injury were demonstrable in the parotid by electron microscopy and consisted of intracellular oedema, sequestered degenerative cell membranes, and an accumulation of intramitochondrial particles. None of these changes was detectable in the submandibular gland. The implication of membrane injury in the lethal effects of radiation on parotid cells is discussed.

The biochemical pathology of liver cell necrosis

Cell death and necrosis are important reactions of liver cells to injury that play a role in a wide variety of human liver diseases. A review is given of the important facets known about the biochemical basis of toxic liver cell death. Liver cells can withstand a great many specific biochemical and morphologic changes without loss of viability. Disturbances in RNA and protein synthesis, mitochondrial function, or release of lysosomal enzymes do not play a primary causative role in cell death. Many previous studies have tended to implicate the plasma membrane and its presumed role in maintaining the proper Ca2+ balance as the primary site of the development of irreversible hepatocyte damage. These studies have generally faced a major difficulty in determining if the observed changes are the cause or an effect of cell death. Galactosamine-induced liver cell injury seems to offer a potentially analyzable model for the experimental analysis of liver cell necrosis. Our studies on the role of plasma membrane injury and associated increases in total cellular calcium are reviewed, and a tentative working hypothesis for the pathogenesis of galactosamine-induced liver cell necrosis is presented.

Early, reversible plasma membrane injury in galactosamine-induced liver cell death

Administration to rats of D-galactosamine (400 mg/kg) produces liver cell death that develops during the first 24 hours. Plasma membranes isolated within the first few hours from these animals show a 40% reduction in 5'-nucleotidase activity and a two-fold increase in maximum negative ellipticity determined by circular dichroism. Simultaneous administration of uridine prevents liver cell death and these early alterations in the plasma membranes. Uridine also prevents cell death if administered for up to 3 hours after galactosamine. The 5'nucleotidase activity reduced when uridine is administered for up to 2-1/2 hours after galactosamine. Changes in the liver calcium ion concentration accompany these plasma membrane alterations. Uridine will prevent and reverse the changes in calcium content in parallel to its ability to reverse the membrane alterations. The significance of these findings with respect to the mechanism of galactosamine-induced liver cell death is discussed.