Autopsies in HIV: still identifying missed diagnoses.

This study reviews the deaths and autopsies carried out over 23 years, 1983-2005, in a British Infection Unit in HIV patients. Of 115 HIV patients known to have died, we obtained data on 93%. Of this 80% were male, median age 38 (25-68) years; 83% were Caucasian; 12% Black African. Major risk factors were men who have sex with men, 52%; heterosexual in Africa, 17%; and injecting drug use, 8%. The commonest diagnosis pre- and post-autopsy diagnosis was pneumonia. Changes in diagnoses in the 38% who underwent autopsy were high (we requested autopsy in 50%). Primary diagnosis changed in 70%, and 36% of all opportunistic infections were missed. This included six of nine cytomegalovirus, all tuberculosis and 75% of Kaposi's sarcoma. Lymphoma was overdiagnosed. Thus, despite excellent resources, the majority of primary diagnoses were wrong, suggesting inadequacy of current diagnostics. To improve these and improve both epidemiological data and future management autopsy should be considered for all deaths.

Cystic neoplasms of the exocrine pancreas.

The increasing use of radiological imaging has led to greater detection of small and asymptomatic cystic lesions of the pancreas. Most are resectable, but not all are neoplastic. This review provides an update on the histopathology, immunohistochemistry, molecular biology, pathogenesis and management of cystic neoplasms of the exocrine pancreas. These include the serous, the mucinous cystic, the intraductal papillary mucinous and the solid pseudopapillary neoplasms. Recently reported variants are described and very rare cystic variants of other pancreatic epithelial and mesenchymal neoplasms are briefly mentioned.

Small, flat colorectal cancers in the UK population: an analysis of resected specimens.

OBJECTIVES: To establish the prevalence of small, flat carcinomas in surgically resected colon. To determine whether tumour morphology influences stage at presentation. METHOD: 1763 surgically resected colorectal cancers from one UK centre excised between 1995 and 2004 were examined. Age 69 years, (42-90), M:F equal. Sixty-one tumours < or =20 mm across were identified. Slides were reviewed by a consultant histopathologist and classified using Japanese Research Society Classification, JRSC and TNM staging. Fisher's exact test was used for analysis. RESULTS: In 61 small cancers, 64% (39/61) showed flat morphology and 33% (20/61) polypoid. Two lesions were unclassifiable. Prevalence was 2.2% of all resected colorectal cancers. More T1 tumours at presentation were polypoid, (30% vs. 8%; P = 0.033). T3 tumours were more likely to be flat than polypoid, (49% vs. 20%; P = 0.016). Infiltration into musclaris mucosa occurred in 77% (30/39) flat tumours. Rates of metastases were high in both groups, (30% polypoid vs. 39% flat, not significant). CONCLUSIONS: The prevalence of small, flat cancers in resected specimens in the UK concurs with that of Japanese studies. Small, flat cancers should be staged carefully because of high rates of T3/4 disease. The results support the theory of accelerated carcinogenesis in flat cancers.

Ectopic thymoma of the chest wall.

A case of ectopic thymoma arising from the chest wall is reported. A chest wall tumour involving the third and fourth ribs and extending extrapleurally and subpectorally was resected following a histopathological diagnosis of hemangioendothelioma obtained at initial incision biopsy. Pathological examination of the excised mass, revealed appearances consistent with a malignant thymoma. No primary thymic tumour was present in the anterior mediastinum so we conclude that the tumour originated in ectopic thymic tissue. To our knowledge a primary thymoma arising within the chest wall has not been reported.

Pancreatic hamartoma.

Pancreatic hamartoma is a rare benign lesion and may be mistaken for a malignancy, as demonstrated by two cases. The first case was a 29-year-old man who presented with a 7-month history of intermittent upper abdominal pain, nausea and vomiting and a 15-kg weight loss. CT and MRI revealed a mass in the head of the pancreas. The second case was a 62-year-old man who presented with a 2-year history of intermittent abdominal pain, vomiting and a 25-kg weight loss. Although positron emission tomography was normal, CT revealed thickening of the duodenal wall and endoluminal ultrasonography revealed a tumour in the head of the pancreas. Both patients recovered from uneventful Kausch-Whipple pancreatoduodenectomy (in the first patient, it was pylorus-preserving), and in each case the histological diagnosis was hamartoma. Pancreatic hamartoma can present with vague, non-specific symptoms which, despite modern diagnostic tools, can be difficult to diagnose. Surgical resection with histopathological examination is required to confirm the diagnosis.

Basal cell carcinoma in Qatar.

BACKGROUND: There is an increasing incidence of basal cell carcinoma (BCC) and skin cancer in general among various countries, where the sun is implicated as an important causative factor. METHODS: Results of clinical and histopathologic examination and the incidence rate of BCCs were recorded over a period of 5 years at Hamad Medical Corporation, Doha, Qatar. RESULTS: Basal cell carcinoma is the commonest skin cancer in Qatar. The average annual incidence per 100,000 residents of working manpower, standardized to the 1986 census, is 9.9 for both sexes and at all ages. Expatriates formed the highest proportion and of these, Europeans were predominant. The tumor was more frequent in men, on sun-exposed areas, was mostly of the nodular and infiltrative type, and occurred in the 3rd, 4th, and 5th decades. As a whole, persons with relatively heavily pigmented skin constituted 66.7% of the patients. CONCLUSIONS: Intense sunlight exposure during outdoor work and leisure activities in Qatar puts residents at increased risk for nonmelanoma skin cancer, even in persons with relatively pigmented skin.

Rhinosporidiosis: immunohistochemical and electron microscopic studies.

Sixteen biopsies of rhinosporidiosis (15 nasal and one conjunctival) from 16 Southern Indian male immigrant workers showed mucosal lymphoplasmacellular infiltrates together with transepithelial elimination of nodular bodies and destruction of some late stage nodular bodies in histiocytic granulomata with central neutrophilic microabscesses. Early nodular bodies were immunohistochemically positive for alpha 1-AT, alpha 1-ACT, CEA, S100, fibronectin, amyloid-p-component, IgG, IgA, C1q and C3. Electron microscopy showed organized concentric lamellated bodies in early nodular bodies and not in end-stage nodular bodies which contained mostly amorphous electron dense materials. Structures formerly regarded as 'sporangia' and 'spores' are believed to be lysosomal bodies loaded with indigestible residues to be cleared via transepithelial elimination or segregated/destroyed by secondary immune/granulomatous responses.

Localized Leishmania lymphadenitis. Immunohistochemical studies.

Tissues from 10 patients with localized leishmania lymphadenitis were stained by immunoperoxidase technique for leishmanian antigens, immunoglobulins (Ig), complement, components, alpha 1-antitrypsin, and fibrin and by routine and chloroacetate esterase techniques. Lymph nodes with leishmania lymphadenitis showed a granulomatous process with a varying degree of necrosis, leishmanian amastigotes, abundant plasma cells, and focal fibrosis. Leishmanian antigens stained by rabbit anti-Leishmania tropica antiserum was detected in lymph nodes with granulomatous lymphadenitis (eight cases examined) and in a skin lesion but not in a lymph node showing only nonspecific hyperplasia. Positive antigen staining was seen in leishmanian amastigotes, granulomata, and (in three cases) vascular smooth muscles. Dominant plasma cell classes were IgG and IgE. Macrophages and granulomata stained positively for IgG and IgE (but not for IgM or IgA), faintly for C3, and strongly for alpha 1-antitrypsin. Mast cells were few. IgG and IgE may be involved in a specific way in this condition; formation of immune complexes with leishmanian antigens leads to immunologically mediated lysis of the host macrophages. This finding is important for the understanding of the pathogenesis of leishmania lymphadenitis and for effective elimination of the parasites.

Glomus tympanicum chemodectoma: unusual radiological findings.

A 64-year-old Qatari female, with a one-year history of right otorrhoea and deafness, had a reddish-white mass projecting into the right ear canal, through the tympanic membrane, that proved histopathologically to be a paraganglioma. Computerized tomography (CT) of the temporal bones showed extensive destruction of the right mastoid bone, the posterior ear canal wall, and the sinus plate, with total disruption of the ossicles, simulating a malignant tumour, which is unusual for a middle ear paraganglioma.

Inflammatory pseudotumor of the spleen: a case report.

An inflammatory pseudotumour of the spleen mimicking a lymphoma clinically is reported. Immunohistochemical studies and the characteristic polymophous inflammatory and fibroblastic infiltrates confirm the lesion as benign.

Spindle cell hemangioendothelioma in association with epithelioid hemangioendothelioma.

A forty-two-year-old man presented with a twelve-year history of a multilobular, firm, but nonulcerated tumor (6 by 4.5 cm) of the dorsum of the right foot. He had capillary telangiectasia of both ankles but no lymphedema. Results of tests for human immunodeficiency viruses I and II were nonreactive. The tumor showed a complex combination of features of spindle cell hemangioendothelioma, epithelioid hemangioendothelioma, and areas suggestive of a possible well-differentiated (lymph) angiosarcoma. The tumor was completely excised with minimal healthy margin. There was no evidence of local or distant lesion at one-year follow-up examination.

Kikuchi's lymphadenitis in Qatar.

The clinicopathologic features of five cases of Kikuchi's lymphadenitis (histiocytic necrotizing lymphadenitis without granulocytic infiltration) occurring in Qatar are presented. There were three females and two males aged from 18 to 36 years with a mean of 29 years. Three were Indians and two were Qataris. Cervical lymph nodes were affected in all cases while one patient also had inguinal and femoral lymph node enlargement. Three patients achieved complete remission within three months. The differential diagnosis both clinically and histologically, included malignant lymphoma, toxoplasmosis, tuberculosis, leprosy, Yersinia and viral infections. To avoid errors in diagnosis, especially that of malignant lymphoma, attention must be paid to the location of the lesion, composition of the cellular infiltrate and the typical fibrinoid type of necrosis in the background.

Esophageal cancer in Qatar.

There were 41 cases of esophageal cancer over a 7 years period in the State of Qatar. Qataris accounted for 30 (73.17%) of these cases while representing about 38% of the entire population. Also there is a slight preponderance of female cases especially among Qataris. Nutritional factors, dietary preferences, environmental factors, social status and habits as well as genetic factors may constitute important etiologic factors in the genesis of esophageal cancer in Qatar.

Endometrial ossification.

A case of endometrial ossification in a 22-year-old woman is reported. Chronic endometritis following post-abortion evacuation was considered the basis for the osseous metaplasia in her endometrium. Besides being a reversible cause of infertility, endometrial ossification needs to be differentiated from mixed mesodermal tumours of the endometrium.

Leprosy in Qatar.

Clinical and histopathologic features of 104 cases of leprosy diagnosed between 1982 and 1989 in the State of Qatar were studied. There were 88 male (84.6%) and 16 (15.4%) female patients aged 18 to 64 years. Eighty-four of the cases were diagnosed during the initial mandatory medical screening on arrival to Qatar. Almost all (103) were expatriates and only one 50-year-old woman was a Qatari. Indians formed the largest group (60.6%), followed by Bangladeshi (6.7%), Pakistani (5.8%), and others. The majority of cases were classified as lepromatous (43.3%) or tuberculoid (43.3%). Although Qatar is a relatively leprosy-free country, the influx of a large number of workers from developing countries seeking employment forms a potential public health hazard.