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Notes: Follicular lymphoid hyperplasia of the hard palate and oral mucosa: report of three cases and a review of the literature Aims: To bring to wider attention this uncommon, poorly understood entity which may closely resemble, clinically and morphologically, follicular lymphoma. Methods and results: We report three cases of follicular lymphoid hyperplasia of the hard palate and oral mucosa which caused diagnostic difficulties for the referring pathologists. The clinicopathological features are described and integrated into a review of the 16 previously recorded cases. The condition most commonly presents as a slowly growing mass situated in the posterior hard palate but may present with multicentric oral lesions and lymphadenopathy. Morphologically, it is characterized by a dense follicular lymphoid infiltrate within the lamina propria which may show the classical features of benign reactive hyperplasia, but not uncommonly, indistinct germinal centres, ill-defined mantles and a lack of tingible-body macrophages are features which may lead to an erroneous diagnosis of follicular lymphoma. Conclusions: Follicular lymphoid hyperplasia of the palate is a poorly recognized entity which is frequently confused with follicular lymphoma. Awareness of the entity combined with the use of immunohistochemistry for immunoglobulin light chains and bcl-2 protein allows a correct diagnosis to be made avoiding extensive investigation and aggressive treatment to the patient.

Notes: Banerjee S S, Verma S & Shanks J H 
(2004) Histopathology44, 2–8 
Morphological variants of plasma cell tumours

Notes: A study of four cases of extra-orbital giant cell angiofibroma with documentation of some unusual features Aims: To document the clinical, light microscopic, immunohistochemical and ultrastructural features of four cases of extra-orbital giant cell angiofibromas. Methods and results: Sections of formalin-fixed paraffin-embedded specimens were studied by haematoxylin and eosin, reticulin and immunohistochemical stains. Electron microscopy was carried out in two cases on tissue fixed in formalin. The age of the patients ranged from 30 to 41 years. Two patients presented with a soft tissue swelling in the left groin, one patient had a left axillary soft tissue lump and one patient presented with a parotid lump. All lesions were well circumscribed and contained variably cellular and vascularized tissue composed of round to spindle cells with a patternless arrangement, scattered multinucleate giant cells and pseudovascular spaces conforming to the description of giant cell angiofibroma. Mononuclear and multinucleate tumour cells were both positive for vimentin and CD34; one tumour exhibited focal S100 protein and GFAP positivity. Both of the tumours examined by electron microscopy showed fibroblastic features, but in addition one contained cells having Schwannian features. All four patients were well without recurrent disease on follow-up (average 25 months). Conclusion: Giant cell angiofibroma shares many features with solitary fibrous tumour and giant cell fibroblastoma and shows a wider distribution than initially recognized. Rarely, Schwannian differentiation may be observed in these tumours.

Notes: Small cell (neuroendocrine) carcinoma of the urinary bladder is clinically more aggressive than urothelial (transitional cell) carcinoma. We have investigated the immunohistochemical markers most useful in diagnosing small cell carcinoma in bladder.〈section xml:id="abs1-2"〉〈title type="main"〉Methods and resultsWe evaluated the expression of chromogranin A, CD44 variant 6 (CD44v6), cytokeratin (CAM 5.2), gamma-enolase, synaptophysin, and CD45 in 46 small cell carcinomas of the bladder. Small cell and urothelial carcinoma were mixed in 21 (46%) cases. The two immunohistochemical markers with best ability to discriminate between small cell and urothelial carcinoma were chromogranin A and CD44v6. Chromogranin A had 97% specificity for small cell carcinoma, staining 65% of cases with 2+/3+ mean intensity; only one case (5%) of urothelial carcinoma was weakly (1+/3+) positive. CD44v6 was 80% specific for urothelial carcinoma, with immunoreactivity in 60% of cases, compared with 7% of small cell carcinoma cases. In cases positive for CD44v6, the mean percentage of reactive urothelial carcinoma cells was 75% (range 10–100%), greater than the 12% of cells in three cases of small cell carcinoma (P = 0.31); further, the pattern of immunoreactivity was membranous vs. focal cytoplasmic, respectively. All small cell carcinomas stained with one of the three neuroendocrine markers tested; 76% of cases were reactive for synaptophysin and 93% for gamma-enolase, with specificities of 86% and 73% in comparison to urothelial carcinoma. γ-enolase staining of small cell carcinoma was more intense (P = 0.01) than for urothelial carcinoma. Cytokeratin CAM 5.2 stained a mean 47% of cells in small cell carcinoma, always in a punctate perinuclear pattern, and 75% in urothelial carcinoma, in a membranous pattern.〈section xml:id="abs1-3"〉〈title type="main"〉ConclusionsCD44v6, chromogranin A, and possibly gamma-enolase and cytokeratin (CAM 5.2) help differentiate small cell carcinoma from urothelial carcinoma.

Notes: As the Reagan administration neared the end of its first full year in office, interpretations of the meaning of the 1980 presidential election were still as varied as the political positions of analysts and commentators. The politically dominant interpretation, promoted by the new administration and its supporters, was that the election provided a mandate to bring about several fundamental changes in the role of government in American social and economic life. In recommendations whose scope had not been matched since the first days of Franklin Roosevelt's New Deal, the Reagan administration set about responding to what it understood to be popular demands for reduced government spending and taxes, expansion of the national defence establishment, limitation of environmental protection in favour of the development of energy resources, and a myriad of other tasks designed to encourage free enterprise by ‘getting government off the backs of the people’. With varying degrees of enthusiasm for the new administration's programmes, scores of Democratic politicians shared the interpretation of Reagan's victory as a new electoral mandate which rejected many of the fundamental policies of Democratic administrations from Roosevelt to Carter. This interpretation of the ‘meaning’ of the 1980 election was expressed by Democratic congressmen of many political colours who decried the bankruptcy of their own leadership and affirmed the victor's sense of mandate by supporting the President's various legislative programmes.

Notes: Testicular Leydig cell tumours are rare. Although most behave benignly ≈ 10% are malignant. Clinicopathological features have been described which have some value in predicting malignant behaviour, although as with other endocrine tumours uncertainties remain in many individual cases. Our aim was to determine the clinicopathological features of 20 testicular Leydig cell tumours. We wished to investigate whether, in addition to established clinicopathological features, the MIB1 index and/or flow cytometric analysis of nuclear DNA content are of value in predicting malignancy. We also wished to investigate the frequency of p53 protein accumulation in these neoplasms.〈section xml:id="abs1-2"〉〈title type="main"〉Methods and resultsTwenty testicular Leydig cell tumours were studied and the clinical case notes examined. Histological sections were assessed by pathologists involved in the study. Pathological features evaluated included: tumour size, extratesticular extension, nuclear pleomorphism, mitotic activity, necrosis and vascular invasion. Immunohistochemical staining was performed with the anti-p53 monoclonal antibody DO-7 and the cell proliferation marker MIB1. A flow cytometric analysis of nuclear DNA content was also performed. Three tumours behaved in a malignant fashion with the development of metastases. Another had morphological features of malignancy but the patient died a short time after diagnosis from unrelated causes. These four neoplasms were larger than benign tumours, often contained areas of necrosis and sometimes exhibited vascular invasion. They generally exhibited greater nuclear pleomorphism and a higher mitotic rate than benign tumours. Three of the four malignant tumours had a high MIB1 index (20–50%) and the fourth exhibited DNA aneuploidy by flow cytometry. Two malignant tumours showed increased expression of p53 protein, with ≈ 50% of nuclei staining with DO-7. All benign tumours had a low MIB1 index (0–2%) and a diploid DNA profile, except for one case where there was DNA aneuploidy. There was little or no staining of benign tumours with DO-7.〈section xml:id="abs1-3"〉〈title type="main"〉ConclusionsThe study confirms that large size, marked nuclear pleomorphism, high mitotic rate, necrosis and vascular invasion are important factors in predicting malignant behaviour in testicular Leydig cell tumours. Additional prognostic value may be derived from the MIB1 index and flow cytometry. Accumulation of p53 protein, through mutational or other events, may be important in malignant progression in these tumours.