Alterations of tumor suppressor gene p16(INK4a )in pancreatic ductal carcinoma

BACKGROUND: Cell cycle inhibitor and tumor suppressor gene p16 / MTS-1 has been reported to be altered in a variety of human tumors. The purpose of the study was to evaluate primary pancreatic ductal adenocarcinomas for potentially inactivating p16 alterations. METHODS: We investigated the status of p16 gene by polymerase chain reaction (PCR), nonradioisotopic single strand conformation polymorphism (SSCP), DNA sequencing and hypermethylation analysis in 25 primary resected ductal adenocarcinomas. In addition, we investigated p16 protein expression in these cases by immunohistochemistry (IHC) using a monoclonal antibody clone (MS-887-PO). RESULTS: Out of the 25 samples analyzed and compared to normal pancreatic control tissues, the overall frequency of p16 alterations was 80% (20/25). Aberrant promoter methylation was the most common mechanism of gene inactivation present in 52% (13/25) cases, followed by coding sequence mutations in 16% (4/25) cases and presumably homozygous deletion in 12% (3/25) cases. These genetic alterations correlated well with p16 protein expression as complete loss of p16 protein was found in 18 of 25 tumors (72%). CONCLUSION: These findings confirm that loss of p16 function could be involved in pancreatic cancer and may explain at least in part the aggressive behaviour of this tumor type

Hypothalamic glioma masquerading as craniopharyngioma

Hypothalamic glioma account for 10-15% of supratentorial tumors in children. They usually present earlier (first 5 years of age) than craniopharyngioma. Hypothalamic glioma poses a diagnostic dilemma with craniopharyngioma and other hypothalamic region tumors, when they present with atypical clinical or imaging patterns. Neuroimaging modalities especially MRI plays a very important role in scrutinizing the lesions in the hypothalamic region. We report a case of a hypothalamic glioma masquerading as a craniopharyngioma on imaging along with brief review of both the tumors

Cutaneous vasculitides: Clinico-pathological correlation

Background: Cutaneous vasculitis presents as a mosaic of clinical and histological findings. Its pathogenic mechanisms and clinical manifestations are varied. Aims: To study the epidemiological spectrum of cutaneous vasculitides as seen in a dermatologic clinic and to determine the clinico-pathological correlation. Methods: A cohort study was conducted on 50 consecutive patients clinically diagnosed as cutaneous vasculitis in the dermatology outdoor; irrespective of age, sex and duration of the disease. Based on the clinical presentation, vasculitis was classified according to modified Gilliam′s classification. All patients were subjected to a baseline workup consisting of complete hemogram, serum-creatinine levels, serum-urea, liver function tests, chest X-ray, urine (routine and microscopic) examination besides antistreptolysin O titer, Mantoux test, cryoglobulin levels, antineutrophilic cytoplasmic antibodies and hepatitis B and C. Histopathological examination was done in all patients while immunofluorescence was done in 23 patients. Results: Out of a total of 50 patients diagnosed clinically as cutaneous vasculitis, 41 were classified as leukocytoclastic vasculitis, 2 as Heinoch−Schonlein purpura, 2 as urticarial vasculitis and one each as nodular vasculitis, polyarteritis nodosa and pityriasis lichenoid et varioliforme acuta. Approximately 50% of the patients had a significant drug history, 10% were attributed to infection and 10% had positive collagen workup without any overt manifestations, while 2% each had Wegener granulomatosis and cryoglobulinemia. No cause was found in 26% cases. Histopathology showed features of vasculitis in 42 patients. Only 23 patients could undergo direct immunofluorescence (DIF), out of which 17 (73.9%) were positive for vasculitis. Conclusions: Leukocytoclastic vasculitis was the commonest type of vaculitis presenting to the dermatology outpatient department. The workup of patients with cutaneous vasculitis includes detailed history, clinical examination and investigations to rule out multisystem involvement followed by skin biopsy and DIF at appropriate stage of evolution of lesions. Follow up of these patients is very essential as cutaneous manifestations may be the forme fruste of serious systemic involvement