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M B Loughrey

Publications and source records attributed to M B Loughrey.

9 recordsLinked to original sources

KIT immunohistochemistry and mutation status in gastrointestinal stromal tumours (GISTs) evaluated for treatment with imatinib.

AIMS: With the availability of effective but expensive treatment in the form of imatinib, accurate diagnosis of gastrointestinal stromal tumour (GIST) is extremely important. The aims of this study were: to describe the clinicopathological, immunohistochemical and molecular features of cases referred to a cancer centre with a possible diagnosis of GIST; to identify pitfalls in the performance and interpretation of KIT immunohistochemistry; to define the role of KIT mutation testing in making a diagnosis of GIST. METHODS AND RESULTS: Morphological review, KIT immunohistochemistry and mutation testing were performed on all cases referred with a diagnosis of GIST or where the diagnosis was under serious consideration on the basis of KIT immunopositivity with a view to treating with imatinib. Thirty-seven cases met the inclusion criteria. Of these, 26 were classified as GIST and 11 as non-GIST. Most GISTs showed strong diffuse membranous, cytoplasmic or paranuclear KIT immunopositivity. Some non-GISTs demonstrated patchy cytoplasmic KIT immunopositivity related to the immunohistochemical protocol used in the external laboratory, which led to erroneous diagnoses of GIST in nine (24%) cases. KIT mutations involving exons 11 or 9 were identified in 22 (88%) GISTs tested and none of the non-GISTs. CONCLUSIONS: An accurate diagnosis of GIST can be made on clinicopathological and immunohistochemical criteria without the need for mutational analysis in most cases, provided proper attention is paid to the immunohistochemical protocol used and, most importantly, control material. False-positive diagnoses of GIST potentially leading to inappropriate treatment with imatinib are more common than missed diagnoses.

Adult↗

Gastrointestinal stromal tumour treated with neoadjuvant imatinib.

This report describes a case of unresectable primary gastrointestinal stromal tumour (GIST) treated with imatinib on a neoadjuvant basis, before subsequent successful surgical resection. After six months of imatinib, computed tomography and positron emission tomography imaging demonstrated a significant size reduction and complete metabolic response to treatment, rendering the tumour resectable. Mutational analysis showed an activating KIT mutation in exon 11. The pathological appearance of the resected tumour was heterogeneous with extensive necrosis, cystic and myxoid change, extensive hypocellularity, and patchy foci of residual viable tumour. The implications for this management option of radiological, pathological, and molecular assessment are discussed.

Aged↗

WHO reclassification of breast lymphomas.

Fourteen cases of breast lymphoma, identified from hospital records between 1990 and 2004, were reclassified according to the World Health Organisation criteria. Primary cases occurred more frequently and all cases were of B cell origin, predominantly involving the right breast. Most primary cases were diffuse large B cell lymphomas, whereas secondary cases were heterogeneous in type and most had a poor prognosis.

Aged↗

Fatal hepatic failure following accidental tramadol overdose.

A case of fatal overdose of tramadol is described, occurring in a 67-year-old man with painful rib fractures who accidentally ingested more than the recommended daily dose. The mode of death was acute liver failure due to fulminant hepatic necrosis. Post-mortem toxicology was negative apart from revealing a blood tramadol concentration well above the normal therapeutic range. This is the first report of fatal tramadol ingestion occurring in a therapeutic setting and also the first tramadol-related death where the mechanism was liver failure.

Accidents↗

An unusual cause of biliary stricture in a patient with neurofibromatosis type 1.

The majority of biliary strictures occur as a consequence of iatrogenic injury to the extrahepatic biliary tract, with more than 80% following cholecystectomy. The laparoscopic era has led to heightened awareness of this problem. The occurrence of an iatrogenic stricture can be particularly devastating to both patient and surgeon. The literature highlights a number of factors involved in the aetiology of such traumatic stricture formation. We report an unusual case of a Bismuth 2 stricture of the proximal common hepatic duct,occurring in a patient with type 1 neurofibromatosis, following an iatrogenic bile duct injury that occurred during a laparoscopic cholecystectomy. Histological examination of the strictured region of bile duct removed at surgery demonstrated multiple neurofibromas of varying sizes present in the submucosa. Neurofibromatosis type 1 (von Recklinghausen disease) affects the gastrointestinal tract in up to 25% of cases, and in such cases is characterized by multiple submucosal neurofibromas. We believe this is the first reported case of a biliary stricture in a patient with neurofibromatosis type 1, which appeared to be as a consequence of neurofibromas in the submucosa of the bile duct.

Adult↗

The declining autopsy rate and clinicians' attitudes.

The autopsy rate has been declining worldwide for decades. This study determined the overall and differential autopsy rates for the Royal Victoria Hospital, Belfast for the years 1997-1999 inclusive. Trends were examined by comparison with previously collected data for the years 1990, 1991 and 1993. Reasons for the decline in autopsy rates as perceived by hospital clinicians were assessed by means of a questionnaire. Over the last decade, there has been a steady decline in the overall autopsy rate from 30.4% in 1990 to 18.4% in 1999. This is due to a decrease in the hospital autopsy rate from 21.6% in 1990 to 7.9% in 1999. The coroner's autopsy rate has remained comparatively unchanged at around 11%. The decline in the overall and hospital autopsy rates involves all of the principal bedholding directorates, but is most dramatic in medicine, surgery and intensive care, where hospital autopsy rates are currently 7% or less. The main reasons for this decline as perceived by clinicians are difficulty in obtaining consent from relatives and advances in modern diagnostic techniques. The findings of this enquiry are in keeping with trends elsewhere, despite repeated studies which clearly demonstrate the continuing value of the autopsy in clinical practice. Recent publicity concerning the retention of organs can only have an adverse affect. Pathologists and clinicians who value the autopsy must become actively engaged in both public and medical education. Renewed emphasis must be placed on the importance of the autopsy in teaching, training and clinically relevant research, and as a means of medical audit.

Adult↗