PubMed Health⌕ Search

Biomedical subjects

R Carpenter

Publications and source records attributed to R Carpenter.

At least 55 records · Page 3Linked to original sources
PubMed1999

Phyllodes tumour of the breast: a retrospective analysis of 30 cases.

Phyllodes tumour (PT) is a rare neoplasm of the female breast that resembles fibroadenoma but occurs in an older age group. We retrospectively reviewed the medical records of 30 women who were treated for phyllodes tumour in our centre. Histological examination was performed by an experienced breast pathologist in all cases and tumours were classified as benign, border line malignant or malignant according to standard histological criteria. The mean age at diagnosis was 49 years (range: 19-80 years). Twenty-one (70%) of 30 tumours were benign and 9 (30%) were malignant (n=7) or borderline malignant (n=2). The mean tumour size was 46 mm (range: 20-100 mm). The final microscopic margins contained tumour in 13 (43%) of 30 cases and were free of tumour in 17 (57%) of 30 patients. After a median follow-up period of 6 years (range: 6 months-20 years), the tumour recurred locally in 5 (17%) patients. One patient had six local recurrences over an 18-year period. Local recurrences were more frequently observed in patients with malignant tumours compared with those with benign lesions (33% versus 10%). However, this association failed to reach statistical significance. There was no association between local recurrence, patient age, tumour size or positive microscopic margins. There was one death (3%) associated with a completely excised malignant tumour. The present study suggests that histological type and margins do not accurately predict the clinical course of PT and that there is a need to identify novel biological markers that more accurately predict the behaviour of this rare neoplasm.

Journal Article↗
PubMed1999

Radial scar and carcinoma of the breast: microscopic findings in 32 cases.

We retrospectively reviewed the microscopic findings in 32 histologically confirmed radial scars in 31 women diagnosed in our unit during 1994-1998. The median age at diagnosis was 53 years (range 47-63 years). Thirty-one (97%) of 32 lesions presented as screen detected mammographic abnormalities (28 stellate lesions, 2 microcalcifications and only 1 architectural distortion). One lesion presented as a palpable breast mass. Stereotactic or ultrasound-guided fine needle aspiration cytology (FNAC) was performed in 28 cases. Cytological analysis of FNAs revealed malignant cells (C5) in 8 (29%) cases, highly suspicious cells (C4) in 3 (11%) cases, atypical benign cells (C3) in 7 (25%) cases and benign epithelial cells (C2) in 10 (35%) cases. All non-palpable lesions were surgically excised following wire localization. Histological examination of the breast specimens (mean weight=16 g) demonstrated, in addition to a radial scar, 6 invasive carcinomas (2 infiltrating ductal, 2 tubular, 1 mixed ductal/lobular and 1 secretory carcinoma) and 4 ductal carcinoma in situ lesions (2 high grade, 1 high grade with micro-invasion and 1 low grade) arising in the radial scar. Of the remaining cases the radial scar was associated with atypical epithelial hyperplasia in 2 cases and regular epithelial hyperplasia in 17 cases (4 florid and 13 mild to moderate). In the 10 cases associated with malignancy, 9 had FNAC and was reported as malignant (C5) in 6 (67%) cases, highly suspicious (C4) in 2 (22%) cases and atypical (C3) in 1 (11%). False positive FNAC (C5) occurred in two patients, one of whom presented with pleomorphic microcalcifications suggestive of ductal carcinoma in situ. This patient was treated with a wire guided segmental mastectomy. All invasive tumours were less than 20 mm in size (T1) and of these 4 were grade I and 2 were grade II. Axillary dissection was performed in 4 patients none of whom had axillary node metastases. Our study demonstrates a significant incidence of malignancy associated with radial scars (31%) suggesting that radial scars may be premalignant lesions. This is supported by detecting various stages of mammary carcinogenesis (atypical epithelial hyperplasia, ductal carcinoma in situ, and early invasive malignancy) in these lesions. Fine needle aspiration cytology seems to be unreliable in the diagnosis of radial scar associated malignancy (67% sensitivity and 91% specificity). Stellate lesions, therefore, should be excised to obtain an histological diagnosis regardless of cytological findings. Further studies examining the biology of radial scars are required.

Journal Article↗
PubMed1999

Granulosa-theca cell tumour of the ovaries. A late metastasizing tumour.

Granulosa-theca cell tumours are ovarian neoplasms of low malignancy with hormone secreting potential, accounting for 2-3% of all ovarian cancers. They have an uncertain clinical course and a potential for late recurrence after surgical removal. Clinical features of a patient presenting with pulmonary metastases 21 years after removal of the primary tumour are described, along with a review of the management options.

Female↗
PubMed1999

Treatment of low rectal carcinoma by transanal electrocoagulation.

This study reports the first 13 cases of biopsy-proven low rectal carcinoma treated by transanal electrocoagulation using a locally manufactured instrument. At the University Hospital of the West Indies, over a 16-year period, 9 patients were treated for cure, six of whom have no clinical evidence of recurrence for one to 12 years. Four cases who were offered this procedure for palliation defaulted after a single treatment. Transanal electrocoagulation provides an additional option for treating patients with small, mobile low rectal cancers, following careful screening for evidence of nodal or distant spread. The procedure can also be used in the local control of disease in patients with distant spread or in whom a major operation is not feasible.

Adenocarcinoma↗
PubMed1999

The challenge of designing a database for auditing surgical in-patients.

Surgical audit is imperative in modern practice, particularly in the developing world where resources are limited and efficient allocation important. The structure, process and outcome of surgical care can be determined for quality assurance or for research. Improved efficiency and reduction of morbidity and mortality are additional goals which may be accomplished. However, computerization, medical staff cooperation and the availability of dedicated staff are among the hurdles which may be encountered. We report the challenge of designing and establishing a database for auditing surgical inpatients in a developing country and the difficulties which were encountered.

Data Collection↗
PubMed1998

The Antirrhinum ERG gene encodes a protein related to bacterial small GTPases and is required for embryonic viability.

Small GTPases have diverse roles in animals and yeast, including signal transduction, regulation of secretion, organisation of the cytoskeleton, and control of cell division. Similar GTPases have also been found in bacteria, such as the Escherichia coli GTPase ERA, which is involved in regulating metabolism and cell division [1,2]. Many small GTPases have been cloned from plants but their functional analysis has largely been limited to complementation of mutations in corresponding yeast genes, and antisense experiments which have implicated these proteins in processes such as root nodulation [3,4]. No mutations in plant GTPases have been reported, and thus their true importance in plant growth and development is unknown. Here we report the isolation of a gene from Antirrhinum majus encoding a protein from an entirely novel class of eukaryotic GTPases showing strongest similarity to the prokaryotic protein ERA. We have named this gene ERG (for ERA-related GTPase). The ERG gene is expressed in dividing or metabolically active cells. We generated a deletion allele of ERG by site-selected transposon mutagenesis and have shown that seeds containing embryos and endosperm homozygous for this deletion arrest soon after fertilisation. We conclude that ERG has a crucial role in plant growth and development, possibly by influencing mitochondrial division.

Amino Acid Sequence↗
PubMed1998

The significance of involved tumour bed biopsy following wide local excision of breast cancer.

AIM: Following wide local excision of breast cancer approximately 25% of patients have residual disease in the tumour bed. The aim of this study was to determine whether positive bed biopsy correlated with either local recurrence or overall survival. METHOD: Following wide excision bed biopsies were taken at four separate sites from the tumour bed. Histopathological assessment of the bed biopsies was made and compared to features within the primary tumour. Patients were followed-up over a median period of 6.17 years and local recurrence and survival data documented. RESULTS: Two hundred and sixty-eight patients were included in the study and 63 had positive bed biopsies. In all, 85 patients had a recurrence of breast cancer and 69 died. Kaplan-Meier plots showed no evidence of a difference in survival between bed biopsy positive and negative patients. Bed biopsy positive patients were at greater risk of local recurrence. CONCLUSIONS: These findings suggest that positive bed biopsy is associated with an increase in local recurrence rates but has no effect on overall survival following wide excision of breast cancer.

Adult↗
PubMed1998

An audit of patient acceptance of one-stop diagnosis for symptomatic breast disease.

AIMS: The impetus for optimizing outpatient provision of breast-care services has come both from the patient and management in order to reduce anxiety and make full use of scarce resources. The one-stop diagnostic clinic for the investigation of symptomatic breast lesions is a relatively recent concept with well-known service benefits. However, acceptance to the patient has not been previously investigated. RESULTS: The results of this prospective audit demonstrate a high level of patient satisfaction with the multi-disciplinary, one-stop breast clinic.

Ambulatory Care↗
PubMed1998

Transcription of the prorenin gene in normal and diseased breast.

The angiotensin II type 1 (AT1) receptor is present in a wide variety of human and animal tissues, and is particularly abundant in epithelial cells. Because of this, and because it is known that tissue renin angiotensin systems (RASs) exist that have specific local functions, we investigated the expression and localisation of components of the RAS in normal and diseased breast tissue. Using a monoclonal antibody to the AT1 receptor, immunocytochemistry confirmed that the AT1 receptor was characteristically distributed in ductal epithelial cells in both normal and malignant tissue, and in most, although not all, cells in invasive tumours. Transcription of prorenin mRNA was studied by in situ hybridisation, using a DIG-ddUTP tail-labelled probe specific for the human prorenin gene. In normal tissue, and in cases of ductal carcinoma in situ, prorenin mRNA was distributed in myoepithelial cells and in a band of connective tissue cells completely surrounding the AT1-containing ductal epithelial cells. This prorenin transcribing tissue was disrupted and attenuated in invasive tumours, and in some of these, prorenin mRNA transcription could not be detected at all. Functions ascribed to the tissue RASs include regulation of mitosis and tissue modelling, as well as fluid and electrolyte transport. The results presented here strongly suggest the possibility that a tissue RAS may also be present in the breast, closely coupled to the provision of angiotensin II to the AT1 receptors in ductal epithelial cells. This mechanism is disrupted in cancer.

Breast Diseases↗
PubMed1998

99mTc-labelled SM3 in the preoperative evaluation of axillary lymph nodes and primary breast cancer with change detection statistical processing as an aid to tumour detection.

The extent of primary surgery for breast cancer could be tailored to the patient if previous information on the presence or absence of lymph node involvement could be reliably determined. Prospective radioimmunoscintigraphy in 29 patients with primary breast cancer that was found on screening has been undertaken with 555 MBq (15 mCi) 99mTc SM3, an Imperial Cancer Research Fund (ICRF) murine monoclonal antibody, 0.5 mg with images at 10 min and 22 h, and analysis using a change detection algorithm. Sites of significant change between the early and later images were displayed as a map of probabilities. Image-positive and -negative axillary lymph nodes were compared by histology in the 28 evaluable patients. The correct identification of the presence or absence of node involvement, even if impalpable, has been shown in 24 out of 28 patients (29 lymph node groups). Sensitivity was 90% (nine out of ten), specificity 84% (16 out of 19) and accuracy 86%. These results encourage further assessment of this technique.

Adult↗
PubMed1998

Control of floral homeotic gene expression and organ morphogenesis in Antirrhinum.

The development of reproductive organs in Antirrhinum depends on the expression of an organ identity gene, plena, in the central domain of the floral meristem. To investigate the mechanism by which plena is regulated, we have characterised three mutants in which the pattern of plena expression is altered. In polypetala mutants, expression of plena is greatly reduced, resulting in a proliferation of petals in place of reproductive organs. In addition, polypetala mutants exhibit an altered pattern of floral organ initiation, quite unlike that seen in loss-of-function plena mutants. This suggests that polypetala normally has two roles in flower development: regulation of plena and control of organ primordia formation. In fistulata mutants, plena is ectopically expressed in the distal domain of petal primordia, resulting in the production of anther-like tissue in place of petal lobes. Flowers of fistulata mutants also show a reduced rate of petal lobe growth, even in a plena mutant background. This implies that fistulata normally has two roles in the distal domain of petal primordia: inhibition of plena expression and promotion of lobe growth. A weak allele of the floral meristem identity gene, floricaula, greatly enhances the effect of fistulata on plena expression, showing that floricaula also plays a role in repression of plena in outer whorls. Taken together, these results show that genes involved in plena regulation have additional roles in the formation of organs, perhaps reflecting underlying mechanisms for coupling homeotic gene expression to morphogenesis.

Base Sequence↗
PubMed1998

A common mechanism controls the life cycle and architecture of plants.

The overall aerial architecture of flowering plants depends on a group of meristematic cells in the shoot apex. We demonstrate that the Arabidopsis TERMINAL FLOWER 1 gene has a unified effect on the rate of progression of the shoot apex through different developmental phases. In transgenic Arabidopsis plants which ectopically express TERMINAL FLOWER 1, both the vegetative and reproductive phases are greatly extended. As a consequence, these plants exhibit dramatic changes in their overall morphology, producing an enlarged vegetative rosette of leaves, followed by a highly branched inflorescence which eventually forms normal flowers. Activity of the floral meristem identity genes LEAFY and APETALA 1 is not directly inhibited by TERMINAL FLOWER 1, but their upregulation is markedly delayed compared to wild-type controls. These phenotypic and molecular effects complement those observed in the tfl1 mutant, where all phases are shortened. The results suggest that TERMINAL FLOWER 1 participates in a common mechanism underlying major shoot apical phase transitions, rather than there being unrelated mechanisms which regulate each specific transition during the life cycle.

Arabidopsis↗