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Morphologic Criteria (morphologic + criterion)
Selected AbstractsProliferation of glial cells in vivo induced in the neural lobe of the rat pituitary by lithiumCELL PROLIFERATION, Issue 4 2000S. Levine Lithium salts are widely used for treatment of psychiatric illness. Lithium also affects cell proliferation. During investigation of the effect of lithium chloride on the central nervous system (CNS) of nephrectomized rats, we noted numerous mitotic figures in the neural lobe of the pituitary. Morphologic criteria established that the mitotic cells were astrocytes, the supporting glial cells of the CNS, also known as pituicytes. Equimolar doses of chlorides of chemically related cations (sodium, potassium, rubidium) had no such effect. [source] Implications of the proposed thyroid fine-needle aspiration category of "follicular lesion of undetermined significance": A five-year multi-institutional analysisDIAGNOSTIC CYTOPATHOLOGY, Issue 10 2009Lester J. Layfield M.D. Abstract National Cancer Institute State of the Science Conference on thyroid fine-needle aspiration (FNA) summarized diagnostic terminology. Six diagnostic categories were proposed including "follicular lesion of undetermined significance" (FLUS). FLUS was defined as findings neither convincingly benign nor sufficiently atypical for a diagnosis of "follicular neoplasm" or "suspicious for malignancy." It was proposed that this category represent less than 7% of thyroid FNAs. A search of the cytology records at three University Hospitals was performed for the term FLUS or older equivalent terms. Usage of FLUS was compared between institutions and among pathologists. Surgical pathology outcome for FLUS cases was determined. Twenty-eight pathologists evaluated 6,872 cases at the three institutions. Use of FLUS varied among pathologists (2.5 to 28.6%). Frequency of use of FLUS among institutions varied from 3.3 to 14.9%. FLUS cases [127 of 673 (18.9%)] underwent surgical exploration with malignancy identified in 36 cases (28.3%) undergoing resection. Use of FLUS varied substantially among pathologists and institutions. FLUS category requires more rigorously defined morphologic criteria for it to become a useful guide in clinical management. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Ceramide levels are inversely associated with malignant progression of human glial tumorsGLIA, Issue 2 2002Laura Riboni Abstract Ceramide represents an important sphingoid mediator involved in the signaling pathways that control cell proliferation, differentiation, and death. To determine whether ceramide levels correlate with the malignant progression of human astrocytomas, we investigated these levels in surgical specimens of glial tumors of low-grade and high-grade malignancy. Tumor samples obtained from 52 patients who underwent therapeutic removal of primary brain tumors were used. The tumors were classified according to standard morphologic criteria and were grouped into tumors of low-grade and high-grade malignancy. Sections of normal brain tissue adjacent to the tumor were also analyzed in 11 of the 52 patients. After extraction and partial purification, ceramide was measured by quantitative derivatization to ceramide-1-phosphate using diacylglycerol kinase and [,- 32P]ATP. Ceramide levels were significantly lower in the combined high-grade tumors compared with low-grade tumors and in both tumor groups compared with peritumoral tissue. The results indicate an inverse correlation between the amount of ceramide and tumor malignancy as assessed by both the histological grading and ganglioside pattern. Moreover, overall survival analysis of 38 patients indicates that ceramide levels are significantly associated with patient survival. The present findings indicate that ceramide is inversely associated with malignant progression of human astrocytomas and poor prognosis. The downregulation of ceramide levels in human astrocytomas emerges as a novel alteration that may contribute to glial neoplastic transformation. The low ceramide levels in high-grade tumors may provide an advantage for their rapid growth and apoptotic resistant features. This study appears to support the rationale for the potential benefits of a ceramide-based chemotherapy. GLIA 39:105,113, 2002. © 2002 Wiley-Liss, Inc. [source] Myopericytoma of the oral cavityHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 6 2007Vivekanand Datta MD Abstract Background. Myopericytoma is a rare mesenchymal neoplasm of pericytic cells demonstrating myoid differentiation. The lesion typically arises within the subcutaneous tissue of the extremities. We report a case that, to the best of our knowledge, is the first case of myopericytoma involving the soft tissue of the oral cavity. Methods. A 36-year-old woman had a 5-mm sessile, whitish-pink, firm tongue nodule. The patient underwent excisional biopsy, and histopathologic examination as well as immunohistochemical analysis were performed. Results. The differential diagnosis by histologic analysis included solitary fibrous tumor, myofibroma, glomus tumor, and myopericytoma. The results of immunohistochemical analysis, when combined with the histologic features, led to a diagnosis of myopericytoma. Conclusions. Applying strict morphologic criteria and appropriately selective immunohistochemical markers will help to distinguish myopericytoma in the oral cavity. © 2007 Wiley Periodicals, Inc. Head Neck, 2007 [source] Human Herpesvirus-8: A Useful Marker for Distinguishing Kaposi Sarcoma and Kaposi Sarcoma-like Pyogenic GranulomaJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005A. Uzieblo Kaposi's sarcoma (KS) is a vascular neoplasm associated with human herpesvirus-8 (HHV-8) infection. On occasion, KS may histologically mimic pyogenic granulomas (PG), a common benign vascular tumor of the skin. Using immunoperoxidase stains, we examined 28 PG and 4 PG-like KS for HHV-8 to determine the specificity of positive staining in this setting. All PG-like KS demonstrated nuclear staining for HHV-8. No staining was identified in any of the PG. Furthermore, histologic criteria often used to differentiate between these two entities were not helpful in difficult cases. The only distinguishing features were the presence/absence of HHV-8 staining and, in some cases, clinical history. The presence of HHV-8 nuclear staining appears to be a specific marker for KS when comparing PG and PG-like KS. Given the lack of distinguishing morphologic criteria, we suggest performing immunoperoxidase stains for HHV-8 on any PG occurring in a clinically atypical setting. [source] Basaloid neoplasms in nevus sebaceusJOURNAL OF CUTANEOUS PATHOLOGY, Issue 7 2000Steven Kaddu Background: Nevus sebaceus (NS) (organoider nevus) may frequently be associated with the development of a number of benign and malignant neoplasms among which basaloid neoplasms are the most common. Histopathologic criteria for diagnosis and classification of basaloid proliferations arising in NS are still debated. Most previous investigators have considered them to represent mainly basal cell carcinomas (BCCs). On the contrary, a number of recent authors have proposed that most basaloid neoplasms in NS exhibit predominantly morphologic features implying benignancy, thus representing trichobalstomas (TBs). In this study, we attempted to characterize better the histopathologic features of basaloid neoplasms in NS in a large series based on current morphologic criteria. Methods: Three-hundred and sixteen cases of NS seen over 19 years were consecutively sampled and reviewed for basaloid neoplasms. Twenty-four cases of basaloid neoplasms in NS were identified and categorized based on current histopathologic criteria either as TB or BCC. For comparison of histopathologic features, 37 solitary TB were also studied. Results: Following histopathologic analysis, 22 cases were categorized as TB (91.6%, 10 males, 12 females; mean age 40.8 years, range 19,78 years) and 2 cases as BCC (8.4%, 1 male, 1 female; 32 years and 40 years). Clinical features in both groups were generally similar. The lesions presented exclusively on the head and neck as skin colored to pigmented papules or nodules within NS (scalp in 19 TB cases and 1 BCC case; face in 2 TB cases and 1 BCC case; neck in 1 TB case). Histopathologically, TB in NS were characterized by smooth-bordered basaloid aggregations with either a nodular and/or a superficial pattern, abundant fibrous stroma with focal clefts within the stroma, and prominent features of limited follicular differentiation (rudimentary follicular germs in concert with papillae). In contrast, BCC in NS showed basaloid aggregations that vary markedly in size and shape, scant fibrous stroma, focal mucinous clefts between basaloid aggregations and surrounding stroma, and lack of prominent rudimentary follicular germs in concert with papillae. Remarkably, sections in a few cases of TB showed features occasionally found in BCCs but presently widely considered to be unspecific (e.g., ulceration, cystic degeneration, and focal clefts between basaloid aggregations and surrounding stroma). Two cases of TB in NS were associated with a sebaceoma and 1 case with a desmoplastic trichilemmoma. Follow-up data in 14 TB cases and 2 BCC cases (mean follow-up 28.8 months; range 1 to 160 months) revealed no local recurrences or distant metastases. Conclusion: Our study confirms that the vast majority of the basaloid neoplasms arising in NS show clear-cut morphologic criteria for TB, whereas only a few cases display histopathologic features consistent with BCC. In a minority of cases, basaloid neoplasms with overall morphologic features of TB may present problems in diagnosis when they exhibit a few histopathologic features traditionally associated with BCC or when they occur in combination with other adnexal neoplasms. [source] Comparison of Four Staining Methods for Detection of Mast Cells in Equine Bronchoalveolar Lavage FluidJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 2 2006Mathilde Leclere Mast cells normally are present in equine bronchoalveolar lavage fluid (BALF), but usually represent <2% of all cells in healthy horses. An increased percentage of mast cells has been associated with airway hyperactivity and inflammatory airway diseases, but marked differences are reported between studies in normal and diseased horses. Because an abnormal mast cell count may be of clinical relevance, we compared the ability of a fast Romanowsky method to stain mast cell granules with that of 3 metachromatic stains: automated Romanowsky, May-Grünwald Giemsa, and toluidine blue stains. The BALF cells from 24 horses were studied. A differential cell count was performed blindly on 400 cells. The percentages of mast cells obtained were analyzed by means of repeated-measures analysis of variance and Fischer's PLSD test. The Bland and Altman method was used to assess agreement among stains. The mean percentage of mast cells in BALF was significantly lower with the fast Romanowsky than with the automated Romanowsky, May-Grünwald Giemsa, and toluidine blue stains. With the fast Romanowsky stain, the metachromatic granules of mast cells were not stained, and their identification was based on morphologic criteria. Toluidine blue staining allowed detection of the highest mean percentage of mast cells, but was inadequate for performing a differential cell count on other cell types. In conclusion, fast Romanosky stain may be inadequate for detection of mast cells in equine BALF, whereas automated Romanowsky, May-Grünwald Giemsa, and toluidine blue stains provide metachromatic staining of mast cell granules. [source] Isolated noncompaction of the ventricular myocardium: contemporary Diagnosis and ManagementCLINICAL CARDIOLOGY, Issue 4 2007Michael P. Chrissoheris M.D. Abstract Noncompaction of the ventricular myocardium is a rare form of cardiomyopathy that has been described since the early 1990s. However, noncompaction remains frequently overlooked, in part due to the limited awareness of its unique clinical and imaging characteristics. Contemporary diagnosis has been facilitated by the introduction of specific morphologic criteria by echocardiography and cardiac magnetic resonance. Management issues revolve around the management of heart failure, arrhythmias, and thromboembolic events in order to prevent the significant morbidity and even mortality that has been associated with this entity. Finally, the genetics of noncompaction have been diverse and an issue of clinical importance as it relates to screening of first-degree relatives of affected patients. Two recent cases are presented and many of the contemporary issues in diagnosis and management, based on an extensive review of the literature, are addressed. Copyright © 2007 Wiley Periodicals, Inc. [source] | |||||||||||||