Cytopathological analysis of vitreous in intraocular lymphoma.

OBJECTIVE: To describe the cytopathological method used in the analysis of vitreous samples in the diagnosis of primary intraocular lymphoma (PIOL). PARTICIPANTS: Seven patients with refractory posterior uveitis referred to a regional ocular inflammatory service were diagnosed as having PIOL between 1999 and 2006. METHODS: Clinical features of the uveitis and cytopathological preparation of the samples were described. All patients underwent vitrectomy and samples were placed in formal saline or prepared fresh. Following paraffin embedding generating a cell block, immunostaining, and polymerase chain reactions were performed. RESULTS: Five women (71.4%) and two men (28.6%) (mean age 67.7 years) were included. Five patients had diagnostic vitrectomy performed within 6 months of presentation, but in two patients diagnosis was delayed up to 2 years. Uveitis was bilateral in two patients. Cytologic and immunohistochemical staining prepared from the vitreous specimens showed PIOL in all patients, and PCR displayed single band of immunoglobulin heavy chain rearrangement in five out of six samples tested. CONCLUSIONS: Diagnosis of PIOL is difficult due to small volume of sample with low number of malignant cells and inadequate preparation of samples. Our method of analysis with fresh samples together with immunohistochemistry and PCR analysis demonstrates a high yield of diagnosis reducing diagnostic delay.

KIT and PDGFRalpha mutational analyses of mixed cell-type gastrointestinal stromal tumours.

AIMS: To determine whether the epithelioid and spindle components of a mixed cell-type gastrointestinal stromal tumour (GIST) show the same receptor tyrosine kinase mutation and, by inference, the same sensitivity to imatinib. METHODS AND RESULTS: Six mixed cell-type GISTs were identified from 108 gastric GISTs. Clinicopathological and immunohistochemical data of the six neoplasms were collated. For each neoplasm, DNA was extracted separately from the laser-microdissected epithelioid and spindle components and non-neoplastic tissue and sequenced for KIT and platelet-derived growth factor receptor (PDGFR)alpha mutations. The epithelioid component often showed less CD117 and/or CD34 immunoreactivity than the spindle component of the same mixed cell-type GIST. Four mixed cell-type GISTs showed somatic KIT mutations (deletions in exon 11 in three tumours and an insertion in exon 9 in one tumour) and one showed a somatic PDGFRalpha mutation (point mutation in exon 18); in each of the five cases, both epithelioid and spindle components showed identical mutations. CONCLUSIONS: The presence of the same receptor tyrosine kinase mutation in both components of a mixed cell-type GIST suggests that both components should be equally responsive to imatinib treatment, and that such mutation is an early key event in the pathogenesis of these neoplasms.

Diabetic muscle infarction: atypical MR appearance.

We describe a case of diabetic muscle infarction which had atypical features of hyperintensity of the affected muscle on T1-weighted images. Biopsy was performed which revealed diffuse extensive hemorrhage within the infarcted muscle. We believe increased signal intensity on T1-weighted images should suggest hemorrhage within the infarcted muscle.

Haemangiopericytoma of the nasal cavity.

Haemangiopericytoma of nose and paranasal sinuses is relatively uncommon tumour. It occurs in adults in sixth and seventh decades of life. In view of paucity of intranasal haemangiopericytoma old in Indian literature and young age of patient, we are reporting one case in 28-year-old female who presented with recurrent, profuse epistaxis.

Primary diagnosis of soft tissue echinococcosis by aspiration cytology.

A case of hydatid cyst of soft tissue diagnosed by Fine needle aspiration of a cyst is reported. The patient presented with gradually increasing swelling in the anterior-inferior aspect of shoulder. The provisional clinical diagnosis of cold-abscess shoulder was made, patient was referred for Fine needle aspiration cytology (F.N.A.C.). Swelling was aspirated by 23-gauge needle obtaining 1.5 ml of blood-mixed fluid. Smears of fluid showed protoscolices, fully developed scolices with rostellum and scattered hooklets, pathognomonic of Echinococcosis. Histopathologic examination of surgically removed cyst showed chronically inflamed echinococcal cyst. No complication was observed.