Incomplete Carney triad--a review of two cases.

A curious association of three rare tumours was described by Carney in 1977. 'Carney's triad' characteristically includes multifocal pulmonary chondroma, gastric stromal sarcoma and extra-adrenal paraganglioma. Patients may exhibit complete or incomplete expression of the triad. Carney acknowledged that, of 79 patients, only 17 possessed all three tumours. We report here two patients with incomplete expression of Carney's triad.

Interdigitating dendritic cell sarcoma of the parotid gland.

Interdigitating dendritic cell sarcomas (IDCSs) are extremely uncommon tumours that arise predominantly in lymphoid tissue. We report a case of an IDCS arising in the parotid gland of a 73-year-old man. Clinically, a primary salivary gland tumour was suspected but fine needle aspiration cytology suggested a soft tissue tumour. A diagnosis of IDCS was made on histopathological examination of the resection specimen, with subsequent confirmation by electron microscopy. Given the extreme rarity of this tumour at this site, it is unlikely to be a common diagnostic problem, but the importance of multiple diagnostic modalities is emphasized. The findings of cytology, histology, immunohistochemistry and electron microscopy have not previously been described together in a single case report of this tumour.

Pathological audit of stapled haemorhoidopexy.

INTRODUCTION: Stapled haemorrhoidopexy is increasingly used for the surgical management of prolapsing haemorrhoids. Accurate placement of the staple line is essential to avoid involvement of the internal anal sphincter (IAS) and the pain sensitive squamous epithelium. The aim of this study was to correlate histology with symptomatic outcome after stapled haemorrhoidopexy. PATIENTS AND METHODS: A single pathologist reviewed one hundred and six consecutive rectal mucosal specimens. Each specimen was assessed for the presence of columnar, transitional and squamous epithelium as well as involvement of smooth and skeletal muscle. In November 2003 all patients were sent a previously validated postal questionnaire about haemorrhoidal symptoms and a Cleveland Clinic continence scale. Symptomatic outcome was compared between patients who did or did not have squamous epithelium involvement in their pathology specimens and were analysed by Mann-Whitney U-test. RESULTS: One hundred and six stapled haemorrhoidopexies were performed between June 2001 and September 2003. Eighty-four patients (79%) returned the questionnaire; 19 patients had squamous epithelium present in the pathology specimens. There was no significant difference between symptom or Cleveland Clinic scores in patients with or without squamous epithelium in their pathology specimens. Some specimens (n = 6) were found to have smooth muscle underlying squamous epithelium; this was interpreted as the presence of internal anal sphincter (IAS) within the specimen. There was no significant difference in Cleveland Clinic scores between this group and those without IAS involvement. CONCLUSION: This study has not demonstrated a long-term difference in symptomatic outcome or continence in patients who have squamous epithelium present in their stapled haemorrhoidopexy specimens.

Primary pulmonary osteosarcoma: case report and molecular analysis.

BACKGROUND: Primary pulmonary osteosarcoma is an extremely rare malignancy. To date, only 12 cases have been reported, with a high mortality rate. The authors report on a newly diagnosed patient and describe investigations that were performed using immunohistochemistry and comparative genomic hybridization (CGH). METHODS: The clinical course of a woman age 37 years is presented. Along with routine histologic examination, immunohistochemistry was used to demonstrate differentiation-associated proteins, oncoproteins, and other markers; CGH analysis for genomic alterations; and histochemistry to demonstrate alkaline phosphatase activity. RESULTS: Immunohistochemical analysis showed varying expression patterns using antibodies against a panel of tumor markers. Most notable was high overexpression of BCL-2 and cyclin D. CGH analysis showed that this neoplasm contained a much higher level of genetic aberrations compared with skeletal osteosarcoma. CONCLUSIONS: This tumor exhibited features common to skeletal osteosarcomas but also had some unique features. Genome analysis suggests that this tumor has several genetic aberrations in common with extraskeletal osteosarcoma. The novel regions of instability identified within the tumor genome may contribute toward the unique tumor phenotype and relative chemoresistance.

Expression of CD44v6 but not E-cadherin or beta-catenin influences prognosis in primary pulmonary adenocarcinoma.

Primary pulmonary adenocarcinoma was studied, looking for relationships between the expression of cell adhesion molecules (CAMs) E-cadherin, beta-catenin and CD44v6, and clinicopathological tumour parameters and patient post-operative survival. Formalin-fixed, paraffin-embedded tissue from 120 primary lung adenocarcinomas, including 23 poorly differentiated tumours, 17 of probable bronchial origin, and 29 with a prominent bronchioloalveolar pattern, together with nodal metastatic tumour from 34 of these patients was stained using monoclonal antibodies and immunohistochemistry. Sections were scored either high level (>10% cells positive) or low level (<10% positive). High level expression of CD44v6 was retained in 28.4% (34/120) of tumours, while high levels of E-cadherin (57.5%, 69/120) and beta-catenin (80. 8%, 97/120) were more frequent. For all CAMs, staining levels did not correlate with nodal status, stage or tumour type. The apical or basal staining seen in normal bronchial and alveolar epithelium was often seen in papillary, glandular, and bronchioloalveolar areas of tumour, while solid invasive tumour more often showed pericellular staining. When the staining for each CAM in 34 nodal metastases was compared with that in the corresponding primary tumour, a high degree of concordance was found, with no tendency for metastases to show less staining than the primary tumour. Expression of E-cadherin and beta-catenin in the primary tumour had no influence on post-operative survival, but patients whose tumours had low level CD44v6 expression had a poorer post-operative survival than those with high levels of CD44v6 (p=0.0014 for all patients, p=0.0012 for stage I patients only). In primary pulmonary adenocarcinoma, the levels of expression of E-cadherin, beta-catenin, and CD44v6 are not associated with lymph node metastases or tumour stage but the staining pattern is associated with tumour morphology. Low levels of CD44v6 expression predict a poor post-operative survival, independently of stage, while there is no such relationship with the expression of E-cadherin or beta-catenin.

The association between atypical adenomatous hyperplasia and primary lung cancer.

Atypical adenomatous hyperplasia (AAH) has been suggested as the adenoma in an adenoma-carcinoma sequence in the lung periphery. From 1989-1998, we undertook a systematic, prospective search for AAH in lungs resected for cancer. AAH was found in 67 of 554 patients (12. 1%) with primary lung carcinoma (9.2% in male patients and 19.0% in females). AAH was found in lungs bearing adenocarcinoma (23.2%) more frequently than with large cell undifferentiated carcinoma (12.5%) or squamous carcinoma (3.3%). A greater percentage of females with adenocarcinoma had AAH (30.2%) than did males with adenocarcinoma (18.8%). Numbers of AAH ranged from 1-42 per patient and more patients had small numbers of AAH, although 12 patients had 6 or more AAH foci. Larger numbers of AAH tended to be found in adenocarcinoma-bearing lungs. Ten of the 67 patients with AAH and primary lung carcinoma (15%) had multiple primary cancers (range 2-6), all of which were adenocarcinoma. Synchronous cancers were rare in lung tumour-bearing resections without AAH. Patients with AAH show no difference in post-operative survival to those without, for all stages of carcinoma and for Stage I disease alone. This study provides evidence for a strong association between atypical adenomatous hyperplasia and primary lung adenocarcinoma and lends weight to the AAH/adenoma-carcinoma hypothesis.

Immune cell infiltrates and prognosis in primary carcinoma of the lung.

The prognostic significance of immune cell infiltrates in surgically resected human lung cancer was investigated in 710 patients. Lymphoid infiltrates were quantified on both standard H&E stained sections and, in a subset of 95 cases, using immunohistochemistry and antibodies to CD3, CD8, CD57, CD68, CD79a and S100 to identify various immune cell types. Subjective grading (low, moderate, high) of lymphoid cell infiltrates on H&E sections of tumour and measurement, using image analysis, of overall level of tumour infiltration by any of the immunohistochemically labelled specific immune cell types of the stained sections showed no prognostic significance. However, when a distinction between peritumoural and intratumoural infiltration by particular cell types was made, intratumoural infiltration by high levels of CD3+ and S100+ cells was associated with longer post-operative survival (P = 0.02 and P = 0.045, respectively). In lung cancer, subjective assessment of tumour lymphoid infiltration and overall levels of infiltration by particular immune cell types carries no prognostic significance. Intratumoural infiltration by relatively high numbers of CD3+ T-lymphocytes and Langerhans cells (S100+) is associated with a better patient outcome.

Right heart failure as the dominant clinical picture in a case of primary amyloidosis affecting the pulmonary vasculature.

A 91-year-old female patient died of right heart failure and pulmonary hypertension. The autopsy revealed multi-organ vascular amyloidosis and pulmonary alveolar septal amyloidosis with no evidence of parenchymal myocardial amyloid deposition. This is a rare example of cor pulmonale secondary to pulmonary amyloidosis.

Structural basis of substrate specificity in malate dehydrogenases: crystal structure of a ternary complex of porcine cytoplasmic malate dehydrogenase, alpha-ketomalonate and tetrahydoNAD.

The structural basis for the extreme discrimination achieved by malate dehydrogenases between a variety of closely related substrates encountered within the cell has been difficult to assess because of the lack of an appropriate catalytically competent structure of the enzyme. Here, we have determined the crystal structure of a ternary complex of porcine cytoplasmic malate dehydrogenase with the alternative substrate alpha-ketomalonate and the coenzyme analogue 1,4,5,6-tetrahydronicotinamide. Both subunits of the dimeric porcine heart, and from the prokaryotes Escherichia coli and Thermus flavus. However, large changes are noted around the active site, where a mobile loop now closes to bring key residues into contact with the substrate. This observation substantiates a postulated mechanism in which the enzyme achieves high levels of substrate discrimination through charge balancing in the active site. As the activated cofactor/substrate complex has a net negative charge, a positive counter-charge is provided by a conserved arginine in the active site loop. The enzyme must, however, also discriminate against smaller substrates, such as pyruvate. The structure shows in the closed (loop down) catalytically competent complex two arginine residues (91 and 97) are driven into close proximity. Without the complimentary, negative charge of the substrate side-chain of oxaloacetate or alpha-ketomalonate, charge repulsion would resist formation production of this catalytically productive conformation, hence minimising the effectiveness of pyruvate as a substrate. By this mechanism, malate dehydrogenase uses charge balancing to achieve fivefold orders of magnitude in discrimination between potential substrates.