Louis T. C. Chow

Metastatic cervical nodes in papillary carcinoma of the thyroid : ultrasound and histological correlation

The ultrasound appearances and histological correlation of metastatic cervical lymph nodes in 20 patients with papillary carcinoma of the thyroid are presented. The majority of the malignant nodes were homogeneous (81.2%), hyperechoic (87.5%) compared to adjacent sternomastoid muscle and 68.7% showed peripheral punctate calcification on US and histology. Histology revealed that the peripheral echogenic foci seen within the nodes on US correlated with psammoma bodies which are characteristic for papillary carcinomas, highlighting the importance of recognizing peripheral punctate calcification in the cervical nodes as a useful sign for the diagnosis of metastatic papillary carcinoma of the thyroid.

Imaging of musculoskeletal tuberculosis: a new look at an old disease.

There are certain imaging features that help to differentiate tuberculosis from other bone and joint disorders with a similar presentation. The current authors discuss these distinguishing imaging features particularly with respect to ultrasound, computed tomography, and magnetic resonance imaging. The judicious and appropriate use of these newer imaging modalities coupled with aspiration or biopsy can lead to earlier recognition of musculoskeletal tuberculosis before the onset of debilitating disease.

Expression of VEGF and MMP-9 in giant cell tumor of bone and other osteolytic lesions.

This study aims to investigate the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) in giant cell tumor of bone (GCT) and other osteolytic lesions in bone. By using semi-quantitative RT-PCR, we showed that three major isoforms of VEGF (121, 165 and 189) were expressed in GCTs, with isoform 121 being the most abundant. The expression levels of VEGF and MMP-9 mRNA were significantly higher in advanced GCTs (stage II/III) than in stage I GCTs. We further elucidated the cellular localization of VEGF and MMP-9 gene transcripts in GCT and other osteolytic lesions using an in situ hybridization assay. The results showed that stromal tumor cells and osteoclast-like giant cells of GCT, fibrous stromal cells in anuerysmal bone cysts and fibrous dysplasia, and Langerhans-type giant cells as well as histocytes in eosinophillic granuloma, were all strongly positive for VEGF and MMP-9 mRNA expression. In a prospective study, we performed VEGF and MMP-9 immuno-staining on paraffin sections of pathological tissues harvested from 48 patients (14 GCT, 10 anuerysmal bone cysts, 10 eosinophillic granuloma, 4 fibrous dysplasia, 2 simple bone cyst, 2 osteomyelitis and 6 patients with fractured femoral head as control). The results showed that the differences in VEGF and MMP-9 expression between Stage I and other advanced Stages (II, III and recurrent) were highly significant (p<0.001), with advanced stages showing a higher mean expression. The difference between recurrent and Stage II and III lesions, was also statistically significant (p=0.03 for VEGF, and p=0.01 for MMP-9 expression), with recurrent lesions showing a higher mean expression of both VEGF and MMP-9. In conclusion, VEGF and MMP-9 expression in osteolytic lesions of bone co-relates well with the extent of bone destruction and local recurrence. Their expression may therefore provide some prognostic indication of the possible aggressive behavior of the underlying pathology.

Effect of Carvedilol in Comparison With Metoprolol on Myocardial Collagen Postinfarction

OBJECTIVES We sought to compare the effects of two different beta-blockers, carvedilol and metoprolol, to an angiotensin-converting enzyme (ACE) inhibitor (captopril) on myocardial collagen deposition during healing and ventricular remodeling after myocardial infarction (MI). BACKGROUND Beta-adrenergic blockade has been shown to be beneficial post-MI and in chronic heart failure. Carvedilol is a new-generation vasodilating beta-blocker with additional alpha1-adrenoceptor antagonism and an antiproliferative action, but it is not known if it is more beneficial than standard selective beta-blockers. METHODS Using a rat model of MI, induced by left coronary ligation, we studied the effects of 11 weeks of therapy with oral carvedilol, metoprolol or captopril on hemodynamics, tissue weights, collagen volume fraction and hydroxyproline content. RESULTS Both beta-blockers caused similar decreases in heart rate and LVEDP compared with untreated post-MI rats. At equivalent beta-adrenoceptor blocking doses, however, carvedilol, but not metoprolol, attenuated the increase in collagen content in noninfarcted regions and prevented the increase in right ventricular weight/body weight (all p < 0.05), and its effect was similar to captopril. Metoprolol treatment tended to increase right ventricular weight and heart weight (p < 0.05). There were no differences in infarct size between the groups. CONCLUSIONS Long-term treatment with both beta-blockers, as well as an ACE inhibitor, benefited the healing process in rats post-MI. At equivalent myocardial beta-adrenoceptor blocking doses, however, carvedilol significantly reduced myocardial collagen in the noninfarcted myocardium and cardiac hypertrophy in the right ventricle, whereas metoprolol had no effect on myocardial collagen deposition.

Left and right ventricular collagen type I/III ratios and remodeling post-myocardial infarction

BACKGROUND Types I and III collagen have different physical properties, and an increase of type I/III ratio can have a deleterious impact on myocardial compliance and left and right ventricular diastolic function. Post-myocardial infarction, these changes in collagen types may be relevant to the remodeling process and the development of heart failure. METHODS AND RESULTS In the rat coronary ligation heart failure model, we studied the time course of changes in types I and III and total collagen levels over 10 weeks postinfarction. Collagen types were separately quantified in the left (LV) and right ventricles (RV) by computerized morphometry and standard immunohistochemistry techniques, and also by hydroxyproline analysis, and these were correlated with hemodynamic changes. Compared with sham-operated rats, total collagen level increased 2.5- to 2.9-fold and 1.7- to 2.9-fold in the noninfarcted areas (NIAs) of the LV and RV, respectively, over the 10-week period and showed a good relation with changes in hydroxyproline content (r2 = 0.62; P < .0001). In the NIAs of both the LV and RV, type III collagen level showed a transient twofold increase at 2 weeks, which declined to normal at 4 weeks. Type I collagen level increased twofold at 4 weeks in the NIA of the LV and remained elevated at 10 weeks. In the RV, type I collagen level increased 2.7-fold to a peak at 4 weeks and declined gradually to 1.7 times baseline at 10 weeks. The patterns of change in type I collagen level in the RV correlated with the changes in LV end-diastolic pressure (r = 0.73; P < .0001) and RV weight to body weight ratio (r = 0.73; P < .0001). CONCLUSION There is a relative greater increase of type I collagen level in the NIA and RV postinfarction, and this may lead to left and right ventricular dysfunction. Separate mechanisms might be involved in the induction of the different types of collagen deposition, with type I collagen levels apparently closely correlating with hemodynamic stress.

Sonographic measurement of splenic length: correlation with measurement at autopsy.

The purpose of this study was to determine the correlations between the sonographic measurement of splenic length and the actual splenic length, volume, and weight.

A new technological approach to nonanatomical pulmonary resection: saline enhanced thermal sealing.

BACKGROUND This is the first clinical report on the feasibility study of two new devices (monopolar Floating Ball and bipolar Sealing Forceps; TissueLink Medical Inc, Dover NH) that incorporated the novel technology of saline enhanced thermal sealing. METHODS From December 2000 to December 2001, 25 patients (mean age, 54.8 years) with peripheral lung nodules planned for either diagnostic or therapeutic wedge resection were recruited for the study. When the nodule lay deep to a flat lung surface, video-assisted thoracic surgical resection using the modified Perelman technique with the Floating Ball (TissueLink Medical Inc) was preferred. In other patients, the Sealing Forceps (TissueLink Medical Inc) were used for video-assisted thoracic surgical wedge resection. RESULTS There were no mortality or major intraoperative complications. The Floating Ball was used exclusively in 11 patients; the Sealing Forceps were used in 9 patients; and a combination of the two devices was used in 5 patients. The mean operation time was 70.3 minutes. Average chest drain duration was 3.9 days, and postoperative hospital stay was 5.2 days. There were 2 patients with persistent air leak more than 1 week, one who resolved spontaneously, and the other who required reoperation for control. One patient had pulmonary embolism after a technically uneventful procedure. There have been no late complications after an average follow-up of 10 months. CONCLUSIONS The devices appear to be technically safe. The Floating Ball has definite advantages over the conventional diathermy and can be adapted to the Perelman procedure using the video-assisted thoracic surgical approach. The Sealing Forceps hold promise to reduce overall consumable costs compared with conventional staplers. These devices should complement the surgeons existing armamentarium. Comparative studies with conventional instruments are warranted to further define the role of these new devices in thoracic operations.

Chronic recurrent multifocal osteomyelitis: a great clinical and radiologic mimic in need of recognition by the pathologist.

The spectrum of histopathologic changes in four cases of chronic recurrent multifocal osteomyelitis encountered in our orthopedic outpatient clinic in the past 3 years was studied in conjunction with clinical and radiologic findings. All presented with pain with or without swelling in the affected region. Radiographically, the appearance of the lesions varied from a mixed picture of bone lysis and sclerosis with expansion to sclerosis alone to bone collapse. Bone scintigraphy demonstrated asymptomatic and separate foci of activity in all cases. Prior to biopsy, the clinical and radiologic differential diagnoses included Ewings sarcoma, metastatic neuroblastoma, hematolymphoid malignancy, Langerhans cell histiocytosis and chronic infection, notably tuberculosis. The spectrum of histopathologic changes ranged from acute (acute inflammatory infiltration, active bone resorption and necrosis, reactive bone formation) to subacute (predominantly lymphocytic and plasma cell infiltration) to chronic inflammation (fibroblastic organization and bony sclerosis). Histologic changes correlated poorly with clinical features, but relatively well with radiologic findings. Lesional excision was performed in one case, cortical saucerization in another, while the final two cases received supportive treatment. All remained well 18–21 months post‐therapy. Chronic recurrent multifocal osteomyelitis is a great clinical and radiologic mimic, which merits recognition by the pathologist. Awareness of the spectrum of histologic features encountered enables a correct diagnosis to be made in the appropriate clinical setting. The patient can thus be reassured of a favorable prognosis.

Primary sclerosing epithelioid fibrosarcoma of the sacrum: a case report and review of the literature

Sclerosing epithelioid fibrosarcoma is a rare tumour characterised histologically by a predominant population of epithelioid cells arranged in strands and nests, embedded in a fibrotic and hyalinised stroma. It is a low grade tumour with an indolent course. A 48 year old woman presented with a painful swelling over her back for six months. Investigation and biopsy revealed features of sclerosing epithelioid fibrosarcoma involving the left half of the sacrum, left sacro-iliac joint, and posterior part of the left ilium. Preoperative radiotherapy and wide location excision of the tumour were followed by metastatic recurrence of the tumour in the lung and scalp six years after initial presentation. The tumour showed typical histology of sclerosing epithelioid fibrosarcoma. The radiological features confirmed its primary location in the sacrum. The patient declined chemotherapy and died of disseminated disease eight years after initial presentation. Review of the literature confirms the fact that sclerosing epithelioid fibrosarcoma, despite its low grade, is a clinicopathologically distinct tumour with full malignant potential, the recurrence, metastasis, and mortality rate being 48%, 60%, and 35%, respectively. Sclerosing epithelioid fibrosarcoma can occur as a primary bone tumour, the clinical behaviour of which is probably similar to its soft tissue counterpart.

Mucinous cholangiocarcinoma : an unusual complication of hepatolithiasis and recurrent pyogenic cholangitis

Mucinous carcinoma is a distinct subtype of adenocarcinoma characterized by the production of abundant extracellular mucin, amounting to more than 50% of the tumour mass. It has been reported in various organs including the stomach, colorectum, breast and pancreas. The gross appearance is characteristic: it has a ‘colloid’ or ‘gelatinous’ cut surface. The practical significance of separating this morphological variant from classical adenocarcinoma lies in the difference in biological behaviour; mucinous carcinomas of the breast are associated with a better prognosis whereas those of the colorectum have a more sinister outcome. In this report, we describe an unusual case of mucinous cholangiocarcinoma occurring in a patient with hepatolithiasis and recurrent pyogenic cholangitis.