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Biomedical subjects

R Carpenter

Publications and source records attributed to R Carpenter.

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

The significance of new densities and microcalcification in the second round of breast screening.

AIM: To assess the nature of new densities and microcalcifications in the second round of breast screening. MATERIALS AND METHODS: A total of 34 634 women were screened at our unit in the second round of the United Kingdom National Health Service Breast Screening Programme. Of those attending for the second time, 302 were recalled for further work-up of 311 new lesions. The lesions were divided into masses, microcalcifications, asymmetric densities and architectural distortions. Masses were classified according to margin and density, and microcalcifications according to morphology and distribution. RESULTS: Among women attending for the second time, the cancer detection rate was 0.45% (89 cancers). One hundred and eighty-eight new masses were identified: 53 well-defined (two malignant), 67 partially defined (six malignant), 54 ill-defined (18 malignant), and 14 spiculate (14 malignant). Well-defined masses were usually cysts, especially in women on hormone replacement therapy. Of 97 new microcalcifications, 71 were pleomorphic (28 malignant), 12 linear (one malignant), and 14 punctate (none malignant). Twenty-five new asymmetric densities were identified (five malignant). One of two architectural distortions was malignant. Malignancy was found in 21% of new masses, 30% of new microcalcification and 20% of asymmetric densities. CONCLUSION: Carcinoma was found in 24% of all new mammographic abnormalities appearing in a 3-year screening period. Spiculate and ill-defined masses, clustered pleomorphic microcalcification, and new asymmetric densities should be regarded with particular suspicion. The use of fine needle aspiration cytology in combination with imaging assessment may help to reduce the number of benign excisional biopsies for new mammographic lesions.

Biopsy, Needle↗
PubMed1999

Randomized double-blind study of the clinical duration and efficacy of Nesacaine-MPF 2% and 3% in peribulbar anesthesia.

PURPOSE: To compare 2 commercially available concentrations of Nesacaine-MPF (2-chloroprocaine) to determine the time to onset of adequate motor blockade, the quality of surgical anesthesia, and the duration of motor blockade in the extraocular muscles after peribulbar anesthesia for cataract surgery. SETTING: Tampa Eye and Specialty Surgery Center, Tampa, Florida, USA. METHODS: This double-blind, randomized, single-center study comprised 40 patients scheduled to receive peribulbar anesthesia before cataract surgery. Patients were given 5 mL of Nesacaine-MPF 2% or 3% before surgery. Beginning at the end of the injection, assessments of ocular and eyelid movement were made every 2 minutes until adequate motor blockade was achieved or 25 minutes elapsed. Ocular assessments were made immediately after completion of surgery, 60 minutes after the end of the initial injection, and at 15 minute intervals thereafter until full recovery. Assessments of the quality of anesthesia achieved by the patient during surgery were made by the surgeon. RESULTS: The 3% solution provided significantly faster onset of surgical anesthesia than the 2% solution (mean 3.9 minutes +/- 2.2 [SD] versus 6.0 +/- 3.6 minutes) (P = .02) but also required more time for recovery from anesthesia (98.9 +/- 18.7 minutes versus 84.8 +/- 20.6 minutes) (P = .02). All patients had adequate surgical anesthesia. Duration of ocular motor function was brief enough so that all patients could be sent home without an eye patch. Both concentrations were safe for use in this procedure. CONCLUSION: Both Nesacaine-MPF 2% and 3% produced safe and effective peribulbar anesthesia in all patients; however, the 3% solution provided better duration of clinical anesthesia.

Aged↗
PubMed1999

The duration of human ocular Chlamydia trachomatis infection is age dependent.

We studied the relationship between age and prevalence, duration and incidence of clinical and laboratory evidence of ocular Chlamydia trachomatis infection in a cohort of Gambian subjects examined bi-weekly for 6 months. The duration of disease and infection, estimated by stratified survival analysis, proportional hazards regression and Weibull modelling, was markedly age-dependent. The estimated median duration of disease was 13.2 weeks in 0-4-year-old subjects and 1.7 weeks in those age 15 and over. Adjustment for multiple infections, and for missing observations did not alter this trend. The cumulative incidence rate of disease was reduced threefold with age. More rapid disease resolution is the main source of reduction in prevalence of active trachoma and ocular C. trachomatis infection with age; disease incidence was reduced to a lesser extent. This age-dependent resolution may be effected by adaptive cellular immune mechanisms. Mechanisms responsible for natural immunity should receive appropriate emphasis in vaccine design.

Adolescent↗
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↗