1/13. Scarring in papillary carcinoma of the thyroid: report of two new cases with exuberant nodular fasciitis-like stroma.AIMS: To describe two new cases of papillary carcinoma of the thyroid with exuberant nodular fasciitis-like stroma, one of which was characterized by previously unreported transformation into a poorly differentiated lesion. Moreover, we explore the presence of TGF-beta to help to clarify the pathogenesis of the collagen formation. methods AND RESULTS: The case characterized by an aggressive behaviour exhibited areas of transformation into a poorly differentiated (insular) carcinoma of the thyroid. In both cases, as revealed by immunohistochemistry, neoplastic cells produced and secreted high amounts of TGF-beta. On the contrary, TGF-beta immunoreaction was never present in the normal thyroid or in papillary carcinomas without collagen bundles, while a weak, exclusively intracellular reaction was present in a patchy manner in cases showing intratumoral fibrous bundles. CONCLUSIONS: The rare variant of papillary thyroid carcinoma characterized by exuberant stroma may give rise to more aggressive lesions, as do other histotypes of differentiated thyroid carcinomas. TGF-beta, the fundamental cytokine which mediates scarring and activation of myofibroblasts, most probably induces the exuberant stroma.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
2/13. Malignant transformation in pleomorphic xanthoastrocytoma--a report of two cases.Pleomorphic xanthoastrocytomas (PXA) with malignant transformation are reported in two adult men with a long history of seizures, recent onset of neurological symptoms and superficially located, temporal lobe lesions. Although PXA is generally described as having relatively benign behaviour, this report adds two further cases of malignant transformation to the literature.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
3/13. Linear spiradenoma with focal malignant transformation.Malignant spiradenoma is an exceedingly rare adnexal tumour clinically characterized by rapid enlargement of a pre-existing, long-standing benign spiradenoma. Microscopic examination typically reveals a continuum between benign spiradenoma and areas of malignant transformation. Biological behaviour is unpredictable and it should be regarded as a potentially lethal neoplasm. Treatment recommendations require radical surgical excision. The reported case of a 23-year-old female illustrates the malignant transformation of a 1.5 cm nodule within a large linear spiradenoma almost covering the frontal aspect of the lower leg. In reviewing the literature, malignant transformation seems to occur slightly more often in multiple than in solitary spiradenomas. It is unclear whether excision restricted to the malignant area is an advisable treatment option in comparison to total excision of all spiradenoma nodules. In the presented case, the transformed area was excised. The patient is free of recurrence after 2 years.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
4/13. Development of leiomyosarcoma from primary leiomyoma?kidney leiomyosarcoma represents a rare variety of malignant kidney tumours. In this paper, we report on a patient with an inoperable leiomyosarcoma. Since this neoplasm is very rare, there is very little information on this type of malignancy. We present the symptoms, radiological findings, diagnostic criteria and differential diagnosis of the tumour. leiomyosarcoma exhibits aggressive biological behaviour and has a poor prognosis. We have found that the treatment of choice is a radical nephrectomy.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
5/13. Unusual cardiac tumour with perivascular myoid differentiation: a case report.A previously healthy 70 year old woman was admitted for fatigue and dyspnoea on exertion and cough. A two dimensional echocardiography revealed a mass in the right atrium, which obstructed filling and infiltrated the cardiac chamber wall. Postsurgical histological examination revealed an unusual tumour with prevalent myoid glomangiopericytoma-type and haemangiopericytoma-like patterns. mitosis and necrosis were absent. A computed tomography scan excluded the presence of metastasis to distant organs or, conversely, metastatic involvement of the heart. Therefore, a diagnosis of tumour with perivascular myoid differentiation was made. This new entity, recently described in soft tissues, can easily recur. Its recognition helps to differentiate from metastasis and other primitive cardiac tumours sharing some morphological features but a different clinical behaviour, with consequent improvement to the management of patient care.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
6/13. Malignant transformation of pleomorphic xanthoastrocytoma.A 31-year-old woman presented with a pleomorphic xantho-astrocytoma (PXA) manifesting as epilepsy. The tumour was partially resected. Histological examination revealed cellular pleomorphism and cytoplasmic vacuolation consistent with PXA, but no mitoses, necrosis, or endothelial proliferation. Follow-up neuro-imaging showed the residual tumour had grown rapidly with dissemination in the spinal cord. The recurrent lesion was totally resected and was shown to be glioblastoma. The patient has survived without signs of recurrence for 36 months after adjuvant radiochemotherapy. The biological behaviour of PXA cannot be predicted based on the histological features and careful follow up is essential.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
7/13. Proliferative verrucous leukoplakia and field cancerization: report of a case.Proliferative verrucous leukoplakia (PVL) is a multi-focal oral pre-malignant lesion, proliferative in nature, with a tendency to recur despite adequate therapy, and a high rate of malignant transformation. The field cancerization phenomenon may explain the characteristic behaviour of PVL. A case of PVL is presented and the field cancerization concept is discussed.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
8/13. Extraspinal ependymoma in the sacrococcygeal region. A case report with ultrastructural, immunohistochemical and cytophotometric studies.We describe on a primary, subcutaneous sacrococcygeal ependymoma presenting in a young female patient. Detailed immunohistochemical and electron microscopic examinations were performed. Out of the 40 similar cases reported in literature this is the first in which the determination of dna content was also used to predict biological behaviour. The tumour proved to be aneuploid with low proliferative capacity in spite of absent histological signs of malignancy. It is suggested that dna determination may be helpful in establishing prognosis and that it may contribute to a better understanding of the biological behaviour of this tumour.- - - - - - - - - - ranking = 2keywords = behaviour (Clic here for more details about this article) |
9/13. Rapid anaplastic transformation in gliomas of adulthood. "Selection" in neuro-oncogenesis.Rapid change of the phenotypical expression is reported in three adult cases of benign or malignant gliomas. Cases with phenomenologically similar thorough alterations have only infrequently been reported in the literature. In all cases the alteration resulted in uniformly small undifferentiated and aggressive cell populations, which would not have permitted diagnosis of the original tumor. Remnants of the latter and the new undifferentiated portions were blended with each other. In two cases the clinical course was characterized by a rapid deterioration within a few months, following as slowly progressive course or periods with only mild symptoms over many years. In his studies of mammary tumors Foulds (1956) found similar phenomena of circumscribed phenotypical changes, to which he applied the term "focal progression". He outlined progression as a basic mechanism in oncogenesis. Later on it has been interpreted as the result of selection of genetically changed subpopulations of tumor cells with an altered, i.e. enhanced malignant expression. They are favoured due to their less demanding behaviour as to environmental conditions. Thus they gradually or rapidly overgrow the original tumor, changing its phenotype. The author believes that the present observations may be interpreted as examples of rapid focal progression in gliomas in terms of Foulds, with "selection" acting as a basic developmental mechanism.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
10/13. Recurrent thymoma: evidence for histological progression.The clinicopathological features of nine cases of recurrent thymomas have been studied. At presentation, all cases were histologically classified as thymomas with cortical differentiation, including predominantly cortical thymoma, cortical thymoma and well-differentiated thymic carcinoma. In five cases the morphological features of the recurrence(s) were suggestive of a histological progression of the tumour from predominantly cortical thymoma to cortical thymoma and/or well-differentiated thymic carcinoma, usually associated with a more advanced clinical stage, the latter indicating a clinical progression. These findings suggest that all types of thymoma with cortical differentiation are histologically and histogenetically related neoplasms, associated with a more aggressive clinical behaviour and a significant risk of recurrence. The overall outcome of patients with recurrent thymoma in this series was poor, since six patients (66.6%) died due to the disease, 2-14 years after the first diagnosis. The clinical implication of our findings is that thymomas with cortical differentiation always need careful follow-up, even in those cases which are not obviously invasive at onset.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
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