Rosette Formation (rosette + formation)

Distribution by Scientific Domains


Selected Abstracts


Small cell carcinoma of the prostate expressing prostate-specific antigen and showing syndrome of inappropriate secretion of antidiuretic hormone: An autopsy case report

PATHOLOGY INTERNATIONAL, Issue 12 2003
Shigeo Kawai
An autopsy case of primary small cell carcinoma (SCC) of the prostate in a 68-year-old man is reported. The patient was admitted to hospital because of a bloody stool and suspected rectal cancer. However, a diagnosis of prostate cancer was made on the basis of a digital rectal examination, the serum level of prostate-specific antigen, and a needle biopsy of the prostate. The patient also experienced a syndrome of inappropriate secretion of antidiuretic hormone. He died 29 days after admission. At autopsy, the tumor had invaded the rectum, bladder and pelvic peritoneum. Metastases to the heart, vertebrae and lymph nodes were observed. Microscopically, the tumor was composed of small round cells that showed a solid growth pattern. Rosette formations were observed. Immunohistochemically, the tumor cells were positive for a prostatic epithelial marker and neuroendocrine markers. A high level of antidiuretic hormone was detected in the tumor tissue. To our knowledge, this is the first reported case of SCC of the prostate in which both a prostatic epithelial marker and neuroendocrine markers have been found in the same tumor. This finding supports the hypothesis that SCC of the prostate originates from a multipotential stem cell of the prostatic epithelium. [source]


Cytologic feature by squash preparation of pineal parenchyma tumor of intermediate differentiation

DIAGNOSTIC CYTOPATHOLOGY, Issue 10 2008
Keiji Shimada M.D., Ph.D.
Abstract Pineal parenchyma tumor of intermediate differentiation (PPTID) is a very rare intracranial tumor, and pathological investigation limited to immunohistological and ultrastructural analyses have been published to date. Although intraoperative cytology is one of the important approaches for initial diagnosis in brain tumors, no or little studies on cellular morphology of PPTID have been demonstrated due to its rarity. We report here cytological features of PPTID obtained from stereotactic surgical specimens in a case of 27-year-old female manifested by dizziness and diplopia. Brain MRI revealed an unhomogeneously enhanced, large-sized tumor (56 × 52 × 60 mm) mainly located in the pineal region expanding from the midbrain to superior portion of the cerebellum and the fourth ventricle. Squash cytology showed increased nucleocytoplasmic ratio, hyperchromatic nuclei, and small rosette-like cell cluster but cellular pleomorphism was mild to moderate and necrotic background was not observed. Histology showed high cellularity, moderate nuclear atypia, and small rosette formation but neither bizarre tumor cells nor necrosis was present. Mitotic counts were very low (less than 1 per 10 high-power fields) and the MIB-1 labeling index was relatively high (10.1%). Tumor cells were immunohistochemically positive for neural markers such as synaptophysin, neurospecific enolase but not for glial fibrillary acidic protein or S-100. In some parts, cells were strongly reactive for neurofilament protein. Taken together, we made a final diagnosis of PPTID. This is the first presentation of cytological analysis by squash preparation that gives an important clue to accurate diagnosis of pineal parenchymal tumor and to understand its malignant potential. Diagn. Cytopathol. 2008;36:749,753. © 2008 Wiley-Liss, Inc. [source]


Autoimmune hepatitis in the Indian subcontinent: 7 years experience

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2001
Rajesh Gupta
Abstract Background: Autoimmune hepatitis (AIH) is presumed to be rare in India. The present prospective study was carried out to determine the prevalence, clinical, biochemical and histological profile of patients with AIH in India. Methods: Consecutive patients with chronic liver disease suspected to be AIH, were screened for antinuclear antibodies (ANA), antismooth muscle antibodies (ASMA), antimitochondrial antibody (AMA), and anti-liver kidney microsomal antibodies (anti-LKM-1). Serum protein electrophoresis and liver biopsy were done. Autoimmune hepatitis was diagnosed according to the International Autoimmune Hepatitis Group criteria. Results: Fifty of 1358 (3.43%) patients with chronic liver disease were diagnosed as autoimmune liver disease; 39 with AIH, two with overlap syndrome, five with primary sclerosing cholangitis, and four with primary biliary cirrhosis. Twenty-nine patients were categorized as definite AIH and 10 as probable AIH. Autoimmune hepatitis was common in females (males : females 1:3), with a mean age of 31 ± 17 years. Patients often presented with fatigue, jaundice and anorexia. Skin lesions (58%), joint symptoms (30%), and menstrual abnormalities (26%) were not uncommon. Mildly elevated alkaline phosphatase and hyper gamma globulinemia were seen in 78 and 91% patients, respectively. Eighty percent of patients were type I AIH, while 20% of cases remained unclassified. Histopathological changes included piecemeal necrosis (100%), plasma cell infiltration (91%), rosette formation (82%), and cirrhosis (76%). Overall mortality was 25% during a mean follow up of 15.7 ± 17.0 months. Conclusions: Our results clearly demonstrate that: (i) AIH is not uncommon in India; and (ii) while the profile and spectrum of AIH resembles that seen in the West, Indian patients present late, often in a cirrhotic state. [source]


Mixed glioneuronal tumour of the fourth ventricle with prominent rosette formation

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 2 2006
T. S. Jacques
We describe three unusual tumours characterized by a mixture of glial and neuronal differentiation, involvement of the posterior fossa and formation of rosettes. Mixed glial-neuronal tumours of the posterior fossa are rare and poorly described neoplasms. However, several distinctive entities have appeared in the literature over recent years under a variety of different names. Our cases demonstrate the morphological features of the ,rosette-forming glioneuronal tumour of the fourth ventricle', a recently identified tumour characterised by its unique location, neurocytic pseudo-rosette formation and the presence of a low grade astrocytoma component. The long term prognosis of these tumours remains unclear. However, the clinical data available including the cases presented here, along with the histological features, suggest that these are low grade tumours with a good prognosis after surgical resection. [source]


Effect of Rds abundance on cone outer segment morphogenesis, photoreceptor gene expression, and outer limiting membrane integrity

THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2007
Rafal Farjo
Abstract We examined the molecular, structural, and functional consequences on cone photoreceptors of the neural retinal leucine zipper knockout (Nrl,/,) mice when only one allele of retinal degeneration slow (Rds) is present (Rds+/,/Nrl,/,). Quantitative RT-PCR and immunoblot analysis were used to assess the expression levels of several phototransduction genes; electroretinography was used to assess quantitatively the retinal responsiveness to light; and immunohistochemistry and ultrastructural analysis were used to examine retinal protein distribution and morphology, respectively. In Rds/Nrl double-null mice, S-cones form dysmorphic outer segments that lack lamellae and fail to associate properly with the cone matrix sheath and the outer limiting membrane. In Rds+/,/Nrl,/, mice, cones form oversized and disorganized outer segment lamellae; although outer limiting membrane associations are maintained, normal interactions with cone matrix sheaths are not, and photoreceptor rosette formation is observed. These retinas produce significantly higher photopic a-wave and b-wave amplitudes than do those of Rds,/,/Nrl,/, mice, and the levels of several cone phototransduction genes are significantly increased coincidently with the presence of Rds and partial lamellae formation. Thus, as in rod photoreceptors, expression of only one Rds allele is unable to support normal outer segment morphogenesis in cones. However, cone lamellae assembly, albeit disorganized, concomitantly permits outer limiting membrane association, and this appears to be linked to photoreceptor rosette formation in the rodless (cone-only) Nrl,/, retina. In addition, photoreceptor gene expression alterations occur in parallel with changes in Rds levels. J. Comp. Neurol. 504:619,630, 2007. © 2007 Wiley-Liss, Inc. [source]