Malignant peripheral nerve sheath tumor of the paranasal sinuses.

Malignant peripheral nerve sheath tumors of the nose and paranasal sinuses are extremely uncommon. We report the case of a 65-year-old woman who presented with a rapid emergence of "nasal polyps" that completely obstructed her nasal passages. Six years earlier she had been assessed elsewhere for nasal polyps. At presentation, the patient exhibited gross polyposis, with lesions protruding from both nostrils. Histology confirmed a diagnosis of a malignant peripheral nerve sheath tumor This case demonstrates that symptoms of nasal obstruction are not always secondary to simple causes. We discuss the clinical picture of nasal and paranasal malignant peripheral nerve sheath tumor, its pathology, and its treatment.

Expression of Fhit, cell adhesion molecules and matrix metalloproteinases in atypical adenomatous hyperplasia and pulmonary adenocarcinoma.

Invasive parenchymal-type lung adenocarcinoma develops from atypical adenomatous hyperplasia (AAH), through an intermediate in situ stage of bronchioloalveolar carcinoma (BAC). We examined the expression of the putative tumour suppressor gene product Fhit, cell adhesion molecules CD44v6, E-cadherin and beta-catenin, and matrix metalloproteinase 2 and its inhibitor, TIMP-2, in a range of AAH lesions, BACs and invasive adenocarcinomas, to determine the changes in molecular expression associated with this form of neoplastic progression. Sections of formalin-fixed wax-embedded archival tissue were stained by standard Immunohistochemical techniques and scored semi-quantitatively, resulting in a grading of negative/low- or high-level staining. Fhit protein was retained at high levels in over 90% of AAH and 83% of BAC, but was found in only 6% of stromally invasive tumours (p < 0.0001). CD44v6 staining was high-level in 64% of AAH but fell to 26% in stromally invasive tumour (p = 0.007). E-cadherin and beta-catenin showed the opposite, with more high-level staining as adenocarcinoma developed (p < 0.001). High-level MMP-2 and TIMP-2 expression was relatively infrequent in AAH (32% and 40% respectively), rose in BAC (89% each) but fell in stromally invasive tumour (31% and 17% respectively) (p < 0.01). Unlike in central bronchial carcinogenesis, loss of Fhit expression is a relatively late event in this putative progression of lung adenocarcinogenesis, and has potential as a surrogate marker of invasion, which could be of value in screening patients for lung cancer. Loss of CD44v6 expression follows the convention of falling adhesion molecule expression as malignancy develops. Increased expression of E-cadherin and beta-catenin may reflect increased cell-cell contact as tissue architecture changes in the transition from AAH to adenocarcinoma. Loss of MMP-2 and TIMP-2 in stromally invasive tumour may reflect a particular role for MMP-2 at the BAC stage, with later down-regulation of this particular enzyme.

Extra-abdominal fibromatosis: a case report.

Head and neck fibromatosis is a rare disease with a variable clinical picture. We report the case of a 40-year-old woman who had a 1-week history of a painless mass overlying her right neck. Histology confirmed a diagnosis of extra-abdominal fibromatosis. Two unusual features of this case were the site of the lesion and its rapid growth. In this article, we discuss the clinical picture of head and neck fibromatosis, its etiology and pathology, and current opinion regarding its treatment.