1/8. Pseudovascular squamous cell carcinoma of the skin.The presence of acantholysis in squamous cell carcinomas (SCC) may rarely be so extreme that, histologically, it mimics a vascular tumour. However, careful histological examination and immunohistochemical study usually lead to the correct diagnosis. We describe such a case to highlight the clinico-pathological features of this rare form of cutaneous malignancy and to emphasize the difficulties in establishing the correct diagnosis. We also review similar cases reported in the literature. Pseudovascular SCC shows a higher degree of recurrence and metastasis than other variants of SCC. Acantholytic foci in these tumours may demonstrate changes in keratinocyte differentiation markers, and this may explain the more aggresive biological behaviour in the pseudovascular variant of SCC.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
2/8. Lipomas of the internal auditory canal--report of two cases and review of the literature.OBJECTIVE: Lipomas of the internal auditory canal are extremely rare. So far, only 21 cases have been described in the literature. We present here two of our own cases and review the literature to date with special emphasis on the diagnostic and therapeutic options. METHOD: During the last seven years two lipomas of the internal auditory canal were surgically treated in our department. Despite native and gadolinium-enhanced MRI and a thin-sliced temporal bone CT scan they were misdiagnosed as intracanalicular acoustic neurinomas. RESULTS: Total tumour removal could be achieved, the facial nerve function was conserved, but both patients were rendered functionally deaf after surgery. CONCLUSION: Lipomas' radiological behaviour may mimic acoustic neurinomas; without fat-suppressed T(1)-weighted images they are often preoperatively misdiagnosed as acoustic neurinomas. Although the postoperative morbidity with respect to cochlear and facial nerve function is much higher than in small acoustic schwannomas, early surgery may be justified, because complete removal is only possible in this stage. No reliable data are available concerning the natural history of this kind of lesion.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
3/8. Adeno-carcinoid or amphicrine tumors of the middle ear a new entity?The clinicopathological, ultrastructural and immunohistochemical characteristics of four primary tumors of the middle ear are reported. These neoplasms showed a striking, heterogeneous aspect ranging from solid-trabecular (Type I) to tubulo-glandular (Type II) growth patterns. Secretory activity of the tumor cells was evaluated by immunohistochemistry and electron microscopy. Based on these procedures, three cell types were found, mainly limited to tumors with a tubulo-glandular (Type II) growth pattern. Most frequent were B-cells with an abundant pale cytoplasm containing neuroendocrine granules, both cytokeratin and vimentin as well as several endocrine marker substances. Less frequent were A-cells, which are slender, darkly staining and line the glandular lumina. They showed exocrine activity only and stained strongly with a polyclonal cytokeratin antibody. Finally, least frequent were amphicrine cells, which were characterized by both lumina and neuroendocrine granules in their cytoplasm and were interpreted as the link between A and B cells. Although this morphological description closely resembles that of carcinoids and adenocarcinoids of the respiratory tract and gut, the clinical behaviour of these middle ear tumors nevertheless seems different, with no recurrence or metastasis after a follow-up of 1 to 14 years (median 78 months). Therefore, some authors suggest that these tumors should be classified as middle ear adenomas or adenomatous tumors. However, we strongly feel that these tumours represent a distinct entity and can be classified as adenocarcinoids or amphicrine tumors, i.e. demonstrating both exocrine and endocrine activities. Further work is required to evaluate the exact proportion of neuroendocrine and amphicrine tumors in the heterogeneous group of adenomas and in the rarely described group of adenocarcinomas.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
4/8. A case of highly aggressive adenoid cystic carcinoma of the external auditory canal.Tumours of the external auditory canal are extremely rare and only 20% of these are of glandular origin. The most frequent histotype is adenoid cystic carcinoma. The rarity of external auditory canal glandular tumours explains the lack of large series reported in the literature and the corresponding large number of case reports from different Authors. Adenoid cystic carcinoma, presenting in the external auditory canal, exhibits the same characteristics as those affecting the major salivary glands, this tumour has an aggressive behaviour characterized by local invasivity and with a metastatic risk of approximately 30%. A rare case of adenoid cystic carcinoma of the external ear is reported. The patient, a 75-year-old male, had right intermittent otorrhea for 6 years. On examination, a vegetating, ulcerated formation which easily bled was found protruding from the right external auditory meatus. Clinical, radiological and pathological features of the tumour are described. A subtotal petrosectomy combined with homolateral elective lymph node neck dissection was performed. parotid gland, condyle of the mandible and VII cranial nerve were spared since these were free from disease.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
5/8. Tissue culture, electron microscopic and enzyme histochemical investigations of extraadrenal paragangliomas.light and electromicroscopical as well as histochemical investigations were performed on three cases of extraadrenal paragangliomas. They were localized in the carotid body, tympanicum and cauda equina region. Tissue of two cases was cultivated in vitro in nutrient medium TCM 199. The tumours were classified as paragangliomas of the paraganglionic type with typical cell clusters, of the adenomatous and angiomatous type. The enzyme histochemistry showed a very high dehydrogenase activity. Ultrastructurally numerous typical osmiophilic granules could be observed in the cytoplasm of the tumour cells. In tissue culture only a minimal cellular proliferative activity could be detected. The few proliferating cell colonies showed mostly characteristics of epithelial tissue and sometimes a similar behaviour to cells of a ganglioneuroblastoma. The minimal proliferative activity in vitro is in good agreement with the proliferative behaviour of the extraadrenal paragangliomas in vivo.- - - - - - - - - - ranking = 2keywords = behaviour (Clic here for more details about this article) |
6/8. Hypothesis: symmetrical cutaneous lymphoma.patients with malignant lymphoma may have cutaneous and subcutaneous involvement that exhibits a striking symmetry about the coronal axis. The symmetry of these lesions may be caused by site-specific migration from the circulation, preferential proliferation by lymphocytes of the neoplastic clones at defined anatomical sites, or both mechanisms. Similar behaviour by benign lymphocytes may explain the symmetry and selective anatomical distribution of lesions in other skin diseases.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
7/8. Middle ear adenoma: a case report with ultrastructural findings.A 56-year-old woman presented with unilateral tinnitus and hearing loss for 18 months. A middle ear mass was detected clinically. At operation, the tumour was found to have eroded the stapes. The light and electron microscopic features of the tumour were those of a middle ear adenoma. This rare benign tumour has an excellent prognosis. Erosion of an ossicle has not been previously associated with this tumour. Benign adenomatous tumours arising from middle ear mucosa are rare (Mills and Fechner, 1984). The term adenoma of middle ear was proposed by Hyams and Michaels (1976), and their review of 20 cases emphasized the benign behaviour of these tumours. We report a case of middle ear adenoma in which ossicular erosion occurred.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
8/8. 'Ceruminoma'--a defunct diagnosis.The clinical and pathological features of glandular tumours of the external auditory meatus are presented. Their heterogenous clinical and pathological features make the collective term 'ceruminoma' ambiguous and misleading. The spectrum of pathological behaviour and histological features demonstrated by these interesting tumours necessitate a broader classification system. In our hospital 32 patients presented with tumours of the external auditory meatus over a 30-year period, of which seven were glandular in origin. A review of the histology of these glandular tumours enabled us to reclassify them as adenoma, cylindroma, adenoid cystic carcinoma or ceruminous adenocarcinoma. Together with the less common mucoepidermoid carcinoma and pleomorphic adenoma this subdivision forms a basis for a more meaningful classification system with prognostic and therapeutic implications specific to each tumour type. The term 'ceruminoma' should no longer be used unqualified.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |