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A 56-year-old man with no previous medical history collapsed and was not able to be resuscitated. The major findings at autopsy were enlargement of the heart (weight = 527 g) which contained an infiltrating firm, homogeneous tumor in an epicardial location adjacent to the left anterior descending and right coronary arteries, with further extension into the right ventricular outflow tract, the interventricular septum and left ventricular free wall. Sections showed sheets of small lymphoid cells with scattered large lymphocytes amounting to a low-grade follicular non-Hodgkin lymphoma, as tumor cells were CD20, CD10, Bcl 2 and LMO 2 positive. This case demonstrates a very rare cause of sudden and unexpected death that resulted from a low-grade follicular lymphoma in an asymptomatic, immunocompetent individual.

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Multiple separate tumors developing in a single salivary gland is rare in previously untreated patients. Tumors that can be multicentric include Warthin tumor, oncocytoma, basal cell adenoma and acinic cell carcinoma. The incidence of multiple primary unilateral pleomorphic adenomas is extremely rare in patients with no prior history of trauma or surgery. We report two cases of primary multicentric pleomorphic adenoma and review the literature. We also subjected one of our cases to a molecular clonality test. The molecular results suggested that the separate nodules were clonally related, arguing against an independent origin.

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The last 20 years have seen a dramatic change in the way we classify, and therefore diagnose, lymphoma. Two decades ago, the International Working Formulation enabled diagnosis and management on the basis of H&E sections alone, with no mandatory requirement for immunophenotyping, molecular studies or any other ancillary investigations. The concept of categorisation by 'clinicopathological entities' defined by clinical features, morphology, immunophenotype and more recently, genotype, began with the Kiel, and Lukes and Collins classifications in the late 1970s, becoming fully expressed in the REAL and subsequently WHO classifications. The current, multidisciplinary approach to categorisation adds significantly to the task facing the anatomical pathologist, since it requires distribution of biopsy material to all the appropriate specialised laboratories, the gathering of a range of cross-disciplinary information, the correlation of all diagnostic findings, deduction of a definitive diagnosis and, finally, integration of all the above into a single multiparameter report. In this review, we summarise the contemporary approach to the biopsy, diagnosis and reporting of lymphoproliferative disorders.

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Screening mammography and greater community awareness of breast carcinoma have led to an increase in fine needle biopsies of the breast. As a consequence, a wide variety of cytologic patterns have been encountered and studied in benign, proliferative, and malignant breast lesions. We review the main reasons for diagnostic difficulties in breast cytology, the situations in which either a false positive or a false negative diagnosis is possible, as well as conditions whose incorrect typing can lead to inappropriate management.

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The pure in situ form of salivary duct carcinoma, also known as intraductal carcinoma, is very rare, and its existence is controversial. We describe a case arising from the minor salivary glands. The patient was a 44-year-old woman who presented with a painless mass in the buccal mucosa. On microscopic examination, the tumor comprised crowded and smooth-contoured epithelial units exhibiting a fenestrated or cribriform pattern, occasionally punctuated by comedonecrosis. An attenuated layer of myoepithelial cells could be demonstrated around all the islands by immunostaining for p63 and actin, indicating absence of an invasive component. The patient remained well following local excision. This case, together with other reported cases, suggests that intraductal carcinoma is a distinct entity. It may represent the preinvasive phase of some invasive salivary duct carcinomas but by itself is nonmetastasizing and associated with an excellent prognosis.

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Lymphoma classification is based on a multiparametric approach to diagnosis, in which clinical features, morphology, immunophenotype, karyotype and molecular characteristics are important to varying degrees. While in most cases, a diagnosis can be confidently established on the basis of morphology and immunophenotype alone, a small proportion of diagnostically difficult cases will rely on molecular studies to enable a definitive diagnosis. This review discusses the various molecular techniques available including Southern blotting (SB), polymerase chain reaction (PCR), fluorescence in situ hybridisation (FISH)--including multicolour-FISH/spectral karyotyping and comparative genomic hybridisation--and also gene expression profiling using cDNA microarray technology. Emphasis is given to the analysis of antigen receptor gene rearrangements and chromosomal translocations as they relate to lymphoma diagnosis and also in the setting of minimal residual disease (MRD) detection and monitoring. Laboratories performing these tests need to have expertise in these areas of testing, and there is a need for greater standardisation of molecular tests. It is important to know the sensitivity and specificity of each test as well as its limitations and the pitfalls in the interpretation of results. Above all, results of molecular testing should never be considered in isolation, and must always be interpreted in the context of clinical and other laboratory data.

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True histiocytic lymphoma/histiocytic sarcoma is an extremely rare, malignant histiocytic tumor. This report is of such a case in a 52-yr-old woman. Fine-needle aspiration (FNA) smears showed large pleomorphic nuclei, prominent nucleoli, moderately dense abundant cytoplasm, and scattered cells with cytoplasmic vacuoles and some with reniform nuclei. Small numbers of background lymphocytes and benign histiocytes were present as well as many multinucleated tumor cells. The immunophenotype was CD45, Lysozyme, CD68 (PGMI), CD43, and S-100 positive. Genotypic analysis revealed a germline configuration. This type of tumor has a large cytological differential diagnosis and immunophenotyping is essential for diagnosis.

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The cytologic features of five cases of epithelial-myoepithelial carcinoma arising in major salivary glands (four parotid and one submandibular gland) are presented. All cases were initially diagnosed as low-grade malignancies. The smears were generally cellular, with no specific architectural pattern. Single cells and naked nuclei were prominent in all cases. A biphasic epithelial (small-cell) and myoepithelial (large/clear-cell) pattern was identified readily in two cases and with difficulty in one case. The biphasic pattern may be subtle or absent since the clear cells have a fragile cytoplasm and often appear as naked nuclei. The differential diagnosis includes adenoid cystic carcinoma, polymorphous low-grade adenocarcinoma, and cellular pleomorphic adenoma.

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AIM: Xanthomas of the colon appear to be rare lesions. Four cases are reported to bring wider attention to this entity. METHOD: Slides, reports and clinical notes from all cases coded as colonic or rectal xanthoma or xanthelasma during the period 1 January 1993 to 1 January 2000 were reviewed. The clinicopathological features are described and integrated into a review of nine previously reported cases. RESULTS: The ages of the patients ranged from 51 to 62 years (2M, 2F). Three lesions were located in the sigmoid colon and one in the rectum. They were all incidental findings at colonoscopy. Grossly, they varied from cream to yellow papules/polyps, ranged in size from 1 to 4mm and were all solitary. Two patients had an associated rectosigmoid hyperplastic polyp. There were no associated cutaneous xanthomatous lesions. One patient was diabetic and the serum lipid levels were normal in all patients. Histologically, all cases consisted of aggregates of mucosal foamy macrophages but in one case there were also macrophages involving the muscularis mucosae. The macrophages were negative for mucin and cytokeratin but were positive for CD68. CONCLUSION: Colonic xanthomas do not appear to be the cause of lower gastrointestinal symptoms and are an incidental colonoscopic finding as well as at times being seen in association with colonic polyps.

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Glomus tumours occur in many sites. We report the first case of a glomangiomyoma in the pancreas of a 17-year-old girl. The tumour was 5cm in diameter and consisted of rounded glomus cells, blood vessels and spindled smooth muscle cells. The glomus and smooth muscle tumour cells showed moderate diffuse cytoplasmic staining with vimentin, muscle-specific actin and smooth muscle actin. There was weak focal positivity for desmin in the spindle cell component only. The patient is alive and well with no evidence of recurrence 24 months after surgery.

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