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Biomedical subjects

R Carpenter

Publications and source records attributed to R Carpenter.

At least 19 recordsLinked to original sources
PubMed2006

Methylene blue dye versus combined dye-radioactive tracer technique for sentinel lymph node localisation in early breast cancer.

AIM: The study compared the accuracy and success rate of two techniques, methylene blue alone versus combined methylene blue and radioactive colloid in sentinel lymph node localisation in the management early breast cancer. METHODS: Three hundred and twenty-nine patients with tumours less than 2 cm on ultrasound assessment were prospectively evaluated. One hundred and seventy-three patients (Group A) underwent sentinel lymph node localisation using 1 ml of 1% methylene blue. A combined technique of both methylene blue and radioactive colloid was used in 156 patients (Group B). Application of both was subdermal and subareolar. Sentinel lymph nodes were examined by standard microscopy. Patients underwent breast conservation surgery or mastectomy and sentinel node guided four node axillary sampling+/-clearance. RESULTS: In Group A, the sentinel lymph node identification rate was 96.5%. The negative predictive value was 96.3%, with false negative of 3.7% and accuracy of 87.4%. In group B the identification rate for sentinel lymph node was 98.7%, with false negative of 4.1%, negative predictive value of 96%, and accuracy of 83.8%. CONCLUSION: Sentinel lymph node localisation using methylene blue or combined dye and radioactive tracer technique predicts the axillary lymph node status in early breast cancer with comparable success rates, accuracy and false negative rates. The combined technique facilitates quicker identification of sentinel lymph node; however the dye technique alone can be used successfully in centres without nuclear medicine facilities.

Axilla↗
PubMed2006

Cyclo-oxygenase-2 (COX-2) mRNA expression and hormone receptor status in breast cancer.

AIMS: The purpose of this study was to evaluate COX-2 mRNA expression with known clinical prognostic features of breast cancer, oestrogen/progesterone receptor status, tumour size and grade. METHODS: Total RNA was extracted from 45 frozen breast tumour (invasive) and 22 normal breast tissue samples. COX-2 mRNA transcription was quantified using a real time RT-PCR assay and expressed as copy number/microg total RNA. All specimens were assessed for tumour grade, size, nodal status and presence of vascular invasion and oestrogen and progesterone receptor status. RESULTS: COX-2 mRNA was detected in all samples with a median copy number of 1.15 x 10(7) for tumours and 6.5 x 10(6) for normal samples. Expression was significantly higher in oestrogen receptor negative tumours compared to the receptor positive group. There was no correlation between COX-2 mRNA levels and tumour size, grade, nodal status and presence of vascular invasion. CONCLUSIONS: COX-2 mRNA expression is increased in oestrogen and progesterone receptor negative breast cancers.

Breast↗
PubMed2006

Selective parathyroid venous sampling in patients with complicated hyperparathyroidism.

OBJECTIVE: The role of preoperative localisation of abnormal parathyroid glands remains controversial but is particularly relevant to the management of patients with recurrent or persistent hyperparathyroidism and familial syndromes. We report our experience of the use of selective parathyroid venous sampling (PVS) in the localisation of parathyroid disease in such patients. DESIGN: We report a retrospective 10-year experience (n = 27) of the use of PVS in complicated primary hyperparathyroidism and contrast the use of PVS with neck ultrasound, magnetic resonance imaging (MRI), computed tomography (CT) and sestamibi imaging modalities. RESULTS: In 14 out of 25 patients who underwent surgery PVS results were completely concordant with surgical and histological findings and 88% of patients achieved post-operative cure. Out of 13 patients referred after previous failed surgery, 12 underwent further surgery which was curative in 9. In total PVS yielded useful positive (n = 13) and/or negative information (n = 6) in 19 out of 25 patients undergoing surgery. Using histology as the gold standard, 59% of PVS studies were entirely consistent with histology, as compared with 39% of ultrasound scans, 36% of sestamibi scans and 17% of MRI/CT scans. CONCLUSIONS: PVS is a valuable adjunct to MRI/CT and sestamibi scanning in selected patients with complicated hyperparathyroidism when performed in an experienced unit.

Adult↗
PubMed2005

Role of aromatase inhibitors in breast cancer.

Primarily, the role of the aromatase inhibitors has been investigated in postmenopausal women with breast cancer, although it is also now being assessed in premenopausal patients following ovarian ablation/suppression. Aromatase inhibitors markedly suppress endogenous oestrogens without directly interacting with oestrogen receptors, and thus have a different mechanism of action to the antioestrogen, tamoxifen. The inhibitors may be divided into subgroups according to their structure (steroidal and nonsteroidal), and there appears to be a lack of cross-resistance between the classes of aromatase inhibitors enabling them to be used sequentially and potentially to prolong endocrine hormone therapy. In addition, with increased efficacy and favourable safety and tolerability profiles, the aromatase inhibitors are starting to challenge tamoxifen as first choice endocrine treatment in a number of settings. Potential differences in side-effect profiles may appear between the steroidal and nonsteroidal aromatase inhibitors when used in long-term settings. Thus, it has been suggested that the steroidal agents have favourable end organ effects; for example, the steroidal inhibitor, exemestane, has minimal negative effects on bone and lipid metabolism in animal and clinical studies. This paper provides an overview of the current and future roles of aromatase inhibitors for breast cancer treatment.

Aromatase Inhibitors↗
PubMed2005

Surgery in the elderly: is age a risk factor?

This prospective, observational one-year study analyzed 623 patients who were 60 years and older, out of a cohort of 2375 patients who were admitted consecutively to the general surgery wards of the University Hospital of the West Indies (UHWI). Even though only 9.7% of the Jamaican population are 60 years and older, this age group accounted for 26.2% of total admissions. Comparison of elderly and non-elderly patients showed no differences in gender, but less elderly patients were emergency admissions (52% vs 64%, p < 0.001), more underwent surgery (68% vs 60%, p < 0.001), their mean hospital stay was longer (11.5 vs 8.0 days, p < 0.001) and their mortality rate was higher (8.8% vs 1.9%, p < 0.001). Emergency admissions (52%) exceeded elective admissions in the elderly. Forty-four (80%) of the 55 deaths in the elderly group were admitted as emergencies compared to elective admissions (p < 0.001). There were 11 deaths among the 296 elective admissions (3.7%) but 44 deaths among the 327 emergency admissions (13.5%), a significant difference in mortality rates (p < 0.001). Overall, the death rate for males was higher. Cancer was the commonest admission diagnosis (21%) and that amongst mortalities. Steps to improve the opportunities for earlier admission and optimization of care of elderly surgical patients would not only benefit them but would be an important step towards a more efficient use of already scarce resources.

Age Factors↗
PubMed2004

Integrin expression and survival in human breast cancer.

BACKGROUND: Integrin cell adhesion molecules are fundamental to numerous cellular functions including anchorage, differentiation and proliferation. Reduced expression of certain alpha and beta integrin subunits in primary breast cancer cells has been correlated with increased invasion and metastasis. Conversely, over-expression of the alpha6 subunit has been linked to poorer survival. The objective of this study was to measure the survival of a cohort with breast carcinoma in relation to integrin expression and to evaluate their potential as prognostic indicators. METHOD: Integrin expression on samples from 99 consecutive patients with breast cancer was assayed using monoclonal antibodies to the subunits alpha(1,2,3,6,V) and beta(1,3,4,5). This cohort has now been followed prospectively for almost five years allowing for early assessment of survival in relation to integrin expression. RESULTS: Whilst analysis of the data confirmed the relation of survival to proven predictors of tumour grade, tumour size and vascular invasion, statistical significance was not demonstrated with regard to both lymph node status and all integrin subunits studied. CONCLUSION: Previous research correlating certain integrin subunits with survival has not been confirmed in this study. Despite proven molecular importance in tumour cell adhesion, invasion and metastasis, integrin expression would appear not to translate clinically as independent indicators of prognosis, at least in the short-term.

Adult↗
PubMed2004

Cancer of the colon and rectum in a Jamaican population: diagnostic implications of the changing frequency and subsite distribution.

The aim of this study was to examine the clinical and pathological characteristics of colorectal cancer in Jamaica, to determine whether there was a change in the anatomic distribution and clinical presentation and to discuss the options for diagnosis and management. A comprehensive retrospective review of patients newly diagnosed with colorectal carcinoma was conducted at The University Hospital of the West Indies by reviewing both patient records and pathological data. These data were compared with previous reports of patients with colorectal cancer seen in Jamaica. One hundred and forty-seven patients were studied There were 85 females and 62 males with a female to male ratio of 1.37:1. The median age was 65.5 years (range 19 to 94 years). The predominant symptoms were abdominal pain in 91 patients, change in bowel habit in 77 patients and rectal bleeding in 74 patients. Sixty patients presented with weight loss and 28 with a rectal mass. The most common tumours were right-sided colonic cancers in 42 patients (28.5%) followed by sigmoid colon in 30 (20.4%) rectum in 34 (23.1%) and left and transverse colon accounting for 16 and 10 cases respectively. Most of the tumours were well or moderately differentiated adenocarcinomas. Only eight patients presented with Dukes' A disease, 50 with Dukes'B, 53 with Dukes'C disease and 34 with advanced disease. The findings showed that sigmoid and rectal tumours accounted for 43.5% of cancers. The colon/rectum ratio in this series was 3.3:1 indicating a significant proximal shift of colorectal cancers in this population in keeping with recent reports. The results of the current study suggest that the sub-site location of colorectal cancers seen is similar to that reported in high incidence countries such as the United States of America and parts of Europe but differs from the African continent which has a high proportion of rectal tumours. This right-sided preponderance also differs from previous studies in Jamaica, which report a higher incidence of rectal lesions The detection of early colorectal carcinoma will require screening at a stage when the disease is asymptomatic in order to improve the chance for cure. The data presented here imply that screening programmes should allow evaluation of the entire colon rather than the distal 25 cm.

Adult↗
PubMed2003

Abdominal ganglioneuromas in adults.

Ganglioneuromas are rare tumours of the parasympathetic nervous system. Their definitive diagnosis is made on histological examination. When they arise from the adrenal medulla, their assessment and management are the same as those of other adrenal tumours. We here report 3 cases of ganglioneuromas highlighting important points regarding the radiological assessment, management, decision making and surgical approaches.

Adrenal Gland Neoplasms↗
PubMed2002

Axillary node status in breast cancer patients prior to surgery by imaging with Tc-99m humanised anti-PEM monoclonal antibody, hHMFG1.

In early breast cancer axillary nodes are usually impalpable and over 50% of such patients may have an axillary clearance when no nodes are involved. This work identifies axillary node status by imaging with a Tc-99m radiolabelled anti-Polymorphic Epithelial Mucin, humanised monoclonal antibody (human milk fat globule 1), prior to surgery in 30 patients. Change detection analysis of image data with probability mapping is undertaken. A specificity of 93% and positive predictive value of 92% (both 100% if a second cancer in the axilla with negative nodes is considered) were found. A strategy for combining negative imaging with the sentinel node procedure is presented.

Adult↗
PubMed2002

Is radiotherapy needed after breast conservation for small invasive breast cancers?

AIMS: The purpose of this study was to determine the rate of local recurrence in patients with small invasive breast cancers (<1 cm) who had been treated with breast-conserving surgery either with (group 1) or without (group 2) adjuvant radiotherapy. METHODS: This is a retrospective study of 110 patients with an invasive breast cancer less than 1 cm in size, treated in our centre by breast-conserving surgery. Parameters examined included age at and mode of presentation, histopathological features, adjuvant therapy, length of follow-up and outcome in terms of local recurrence rate and death. RESULTS: In group 1 there were 59 women of median age 57 (38-80) years. The median tumour size was 9 (1-10) mm and median follow-up was 74 (15-110) months. There were no local recurrences. In group 2 the median age at presentation was 59 (48-81) years. The median tumour size was 7 (2-10) mm and median follow-up was 47 (14-93) months. There were three non-breast-cancer related deaths and three local recurrences (6%). CONCLUSIONS: A local recurrence rate of 6% at almost 4 years median follow-up suggests that it may be possible to avoid adjuvant radiotherapy in a subgroup of largely screen-detected, node-negative patients with invasive tumours less than 1 cm, in whom adequate local excision is performed. Further follow-up is required to substantiate this.

Adult↗
PubMed2002

Infiltrating fibromatosis of the breast: a potential pitfall.

Mammary fibromatosis is a rare condition. It presents a big dilemma for the clinician, because it mimics breast cancer clinically, radiologically and sometimes cytologically. We report a case of fibromatosis of the breast and highlight the diagnostic difficulties and management.

Biopsy↗
PubMed2002

How significant is detection of ductal carcinoma in situ in a breast screening programme?

PURPOSE: To compare the histological grades of screen detected and non-screen detected ductal carcinoma in situ (DCIS) and to identify any differences that might support the contention that DCIS found by breast screening represents an over-diagnosis. The aim was also to establish whether any particular mammographic features of DCIS can be used to predict tumour grade reliably. MATERIALS AND METHODS: Biopsy proven cases of DCIS (n=153) were reviewed with respect to grade and subdivided into high, intermediate and low grades using the Van Nuys classification. A more aggressive subset of DCIS (microinvasive and interval cancers) were similarly analysed. Mammograms were reviewed with regard to abnormal features and distribution, and the appearances correlated with grade. RESULTS: Fifty-four percent (53/98) of screen detected and 62% (34/52) of non-screen detected DCIS were high grade. The rest were equally intermediate and low grade, with no statistical difference between the two groups. Eighty-four percent of the aggressive subset of tumours were high grade. Micro-calcification was present in 90% and in 10% there were soft tissue changes alone. Seventy-six percent of linear branching calcification was associated with high grade DCIS. Only 13% of high grade DCIS demonstrated punctate micro-calcification; however, 38% of cases of punctate micro-calfication were associated with high grade tumours and there was a great deal of overlap between the groups. CONCLUSION: Most cases of DCIS in both screen and non-screen detected groups were high grade. Only one in five was low grade. Analysis of the aggressive subgroup underlines the significance of high grade DCIS. Mammographic patterns are not always reliable in the prediction of tumour grade. The detection of DCIS in screening programmes is important and should not be regarded as over-diagnosis.

Adult↗
PubMed2001

Predictors of positive margins after local excision of ductal carcinoma in situ.

BACKGROUND: This study aimed to examine the association between clinicopathologic parameters and positive margins in women with ductal carcinoma in situ (DCIS) treated by breast-conserving surgery (BCS). METHODS: We retrospectively reviewed the clinical, radiologic, and pathologic data of 100 women who had undergone BCS for DCIS in our center. RESULTS: Sixty-seven percent of patients presented via breast screening and 55% of all cases were diagnosed preoperatively on fine needle aspiration cytology ([FNAC] ie, C5). Overall, 45% of patients had clear margins after initial local excision. Positive margins showed a nonsignificant trend of association with distribution of microcalcifications (MCC), nonconsultant operating surgeon, inconclusive preoperative FNAC, presence of necrosis, and low specimen weight. There was a highly significant association between low grade DCIS (P = 0.003) and incomplete excision. There was no significant association with age, associated invasive focus, morphology of MCC, or with mode of presentation. CONCLUSION: Positive margins after local excision of DCIS are significantly associated with low nuclear grade, and preoperative determination of nuclear grade by core biopsy may have surgical implications.

Biopsy, Needle↗
PubMed2001

Concomitant off-pump myocardial revascularization and pheochromocytoma resection.

Surgical management of patients with coexisting ischemic heart disease and pheochromocytoma remains challenging. We present one such case in which hybrid myocardial revascularization (angioplasty with stenting and off-pump coronary artery bypass grafting) and resection of pheochromocytoma were undertaken. Unusual features included simultaneous coronary artery surgery and tumor resection and, in particular, coronary artery surgery being performed without cardiopulmonary bypass.

Adrenal Gland Neoplasms↗
PubMed2001

The gene fimbriata interacts non-cell autonomously with floral regulatory genes.

In Antirrhinum majus, one proposed role of the gene fimbriata (fim) is as a mediator between the floral meristem identify gene floricaula (flo) and floral organ identity genes such as deficiens (def) and plena (ple). The mechanism of fim activity is probably unique as, while the other genes in the hierarchy are thought to be transcription factors, fim is thought to target proteins to a ubiquitin-mediated destruction pathway. Both flo and def have been shown to act non-cell autonomously. We tested the hypotheses that (i) fim acts in a non-cell autonomous manner; and (ii) non-cell autonomy of flo might be through activation and subsequent non-cell autonomous activity of fim. Plants bearing an unstable fim allele were monitored for revertant shoots. Analysis of fim RNA expression in plants derived from revertant shoots, and segregation of revertant phenotype in progeny from revertant plants, indicated that all were periclinal chimeras with wild-type fim expression only in subepidermal layers. Despite the absence of fim in the epidermal layer, expression of downstream genes was normal, suggesting non-cell autonomous activity of fim. Subsequently, we tested the hypothesis that fim is the mediator of flo non-cell autonomy by examining fim expression in flo periclinal chimeras. In these chimeras, fim is activated in cells where flo is not expressed, indicating that fim cannot be the sole mediator of flo non-cell autonomy.

Chimera↗