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Biomedical subjects

B O'Sullivan

Publications and source records attributed to B O'Sullivan.

126 records · Page 7Linked to original sources

How expert physicians would wish to be treated if they had genitourinary cancer.

A questionnaire describing six clinical scenarios was mailed to urologists (in Britain, Canada, and the United States) and to radiation and medical oncologists in the United States, who practice genito-urinary (GU) oncology. In each scenario, the surgeon or physician was asked to consider himself as a patient with bladder, prostate, or kidney cancer, and to select his own treatment. Accompanying each scenario were one or two clinical trials for which the physician would be eligible. He was asked to state if he would agree to be randomized in each trial, and if he refused, to state his reasons. We found that (1) there were major differences of opinion about management for each scenario; (2) choice of treatment was influenced more by specialty training or geographic location than by the results of previous clinical trials (which are available to all); (3) British urologists tended to be less aggressive than their North American colleagues, with respect to the use of radical surgery and chemotherapy; (4) acceptance of clinical trials ranged from 3% to 60%; and (5) agreement to clinical trials was quite poor even when they were designed to compare the most popular options for management. This physician surrogate method is a valuable tool in assessment of the degree of consensus amongst expert physicians and in the determination of whether new clinical trials address important areas of controversy.

Adult↗

Limb-sparing management in extremity soft-tissue sarcomas in the adult: the radiation oncologist's viewpoint.

Current management of extremity soft-tissue sarcomas achieves local control in a high proportion of patients. This paper describes the local methods to conserve limb function that have largely replaced traditional approaches of ablative surgery. Frequently, these methods employ conservative surgery with preoperative or postoperative radiotherapy. An understanding of the biology and behaviour of these rare tumours is necessary to optimize the goals of limb conservation without compromising local control. Appropriate surgical and radiotherapy techniques are facilitated by planned pretreatment staging methods and communication between the surgical and radiation oncology teams. Although a high rate of local control can be expected, distant metastases continue to be a problem. Future strategies should be directed towards scheduling of optimal local treatments with the investigation of adjuvant systemic methods to reduce the rate of distant metastases.

Adult↗

Non-small cell lung cancer: how oncologists want to be treated.

One hundred and eighteen Canadian doctors who treat lung cancer were asked how they would wish to be managed if they had non-small cell lung cancer. Four clinical situations were described. The doctors' replies to the open-ended management questions were remarkably consistent in view of their diverse backgrounds. Although opinion was divided as to the role of immediate radiotherapy in inoperable cancer, and the role of post-operative radiotherapy following incomplete surgery, there was little controversy as to the role of chemotherapy. Three per cent of doctors wanted adjuvant chemotherapy after surgery for early disease, 9% wanted chemotherapy for advanced disease confined to the chest and 15% wanted chemotherapy for symptomatic metastatic disease. The implications of these results are discussed in the light of current recommendations for treatment of non-small cell lung cancer in the standard North American textbooks of oncology.

Canada↗

The use of expert surrogates to evaluate clinical trials in non-small cell lung cancer.

One hundred and eighteen doctors who treat pulmonary neoplasms in Ontario were asked how they would wish to be treated if they had non-small cell lung cancer. Four different scenarios were given. The physicians were then asked if they would consent to take part as subjects in one or more clinical trials for which they would be eligible in those situations. The proportion of respondents who would consent to each study ranged from 11% to 64%. Reasons given for refusing to participate as subjects in each trial were varied, but many felt that the trials offered unacceptable options for treatment. Medical oncologists consented to each study more frequently than radiation oncologists, respirologists or thoracic surgeons but all disciplines ranked the 6 studies in the same order of acceptability. It is concluded that some patients with non-oat cell lung cancer currently receive experimental therapies with high risk/benefits ratios which experts in the field would not accept for themselves. It is suggested that the expert surrogate system may be useful as an adjunct to the institutional review board in evaluating new trials before they are activated.

Attitude of Health Personnel↗

Mammographic patterns and breast cancer risk: methodologic standards and contradictory results.

The claim that classification of the pattern of the breast parenchyma upon mammography can distinguish groups at different risks for breast cancer has been examined by 17 other studies published in the English language literature with contradictory results; this controversy was assessed by us in examination of these studies for their adherence to commonly accepted methodologic standards for the investigation of causal relationships. The nine standards for the examination of the studies included a description of the way the study population had been assembled and followed up and descriptions of the methods of mammographic pattern classification and breast cancer risk analysis. A strong association was found between the standards adopted by a study and the obtained results. Among nine cohort and case-control studies that found a statistically significant association between mammographic pattern and breast cancer risk, all met at least four standards, whereas only two of six "negative" cohort or case-control studies met as many as four standards. Among prevalence surveys, the association between methods and results was less striking, but several negative prevalence surveys were associated with "positive" cohort studies employing the same group of patients. These results indicate that methodologic differences among studies contribute substantially to the controversy surrounding this subject. Studies that follow the usual scientific methods employed in the epidemiologic investigation of risk generally have confirmed an association between mammographic pattern and breast cancer risk.

Age Factors↗

Bias and the association of mammographic parenchymal patterns with breast cancer.

We have carried out a case-control study to evaluate the association between Wolfe's mammographic patterns and the risk of breast cancer, and to examine the influence of control selection and the radiologist who read the films upon the results obtained. Mammograms of the non-cancerous breast of 183 women with unilateral breast cancer were compared with mammograms from two age-matched control groups: a group of asymptomatic women attending a screening centre, and a group of symptomatic women referred for the diagnostic evaluation of suspected breast disease. Films were arranged in random sequence and independently classified by 3 radiologists. A strong and statistically significant association was found between mammographic dysplasia and breast cancer when controls from the screening centre were compared to cases, but not when cases were compared to women referred for the diagnostic evaluation of breast disease. This result appears to arise in part because of an association between symptoms of benign breast disease and mammographic dysplasia, and suggests that some previous negative studies of the association of mammographic patterns with breast cancer may have arisen from the inclusion of symptomatic subjects as controls.

Adult↗

Mammographic signs as risk factors for breast cancer.

We have carried out a case-control study to examine the relationship between mammographic signs and breast cancer. The mammographic signs assessed were prominent ducts and dysplasia. The cases were a group of 183 women with histologically verified unilateral breast cancer. The controls were a group of women attending a screening centre. Cases and controls were individually age-matched. Mammograms from the non-cancerous breast of the cases were randomly assembled with those of the controls and classified by 3 radiologists without knowledge of which films were from cases and which from controls. Mammographic dysplasia was found to be strongly associated with breast cancer, particularly in women aged less than 50. Prominent ducts were only weakly associated with breast cancer. Multivariate analysis showed that the association between dysplasia and breast cancer could not be explained on the basis of other risk factors for breast cancer, and that classification of dysplasia discriminated more strongly between cases and controls than did classification of Wolfe's mammographic patterns. These results show that mammograms contain information about risk of breast cancer. Mammographic dysplasia is strongly associated with breast cancer, is present in a substantial proportion of patients with the disease, and may offer opportunities for prevention.

Adult↗

Mammographic patterns and bias in breast cancer detection.

Wolfe's finding that some mammographic patterns (P2 and DY) are associated with an increased risk of breast cancer has been challenged by some authors who suggest that this is due to denser patterns concealing cancers present on the first examination: these cancers, it is argued, are diagnosed in later years, creating the spurious impression of increased cancer incidence. The authors examined this hypothesis in a series of patients with breast cancer but failed to find any evidence that the diagnosis was subject to systematic delay in patients with the P2 or DY pattern. Moreover, studies of a hypothetical model showed that bias in the detection of breast cancer was unlikely to account for more than a small increase in apparent cancer incidence. Thus it appears unlikely that such a bias is responsible for the risk of breast cancer observed in patients with these mammographic patterns.

Adult↗

Ataxia and spinal cord degeneration in llama, wildebeeste and camel.

Clinical and pathological findings from instances of ataxia in a group of wildebeeste (Connochaetes taurinus), two llamas (Llama glama) and one Arabian camel (Camelus dromedarius) are presented. Clinically, all the affected animals showed a non-febrile, progressive ataxia. Neuropathologically, Wallerian degeneration was diffuse in the spinal cord of the camel and llamas but was focal in the wildebeeste. Degeneration was present in the cervical dorsal roots in the wildebeeste and in the ventral nerve roots at all levels of the cord in the llamas. Peripheral nerve were affected in all the species. The possible roles of copper deficiency and plant poisons in the aetiology of the condition are discussed.

Animals↗

Contemporary radiotherapy for soft tissue sarcoma.

This review will detail the role of radiotherapy in the management of soft tissue sarcoma. Particular emphasis will be given to its role as an adjuvant to surgical excision for local curative management. The addition of radiotherapy permits a tissue-conserving operation to be performed, which has functional and cosmetic advantages yet produces local control equivalent to more radical surgery alone. The review will consider the historical evolution of treatment up through recent and contemporary practice. The principles of use will be outlined using available evidence and, where this is lacking, it will be acknowledged with suggestions for improvement. Finally, a brief overview of some technical issues about radiotherapy will be provided.

Combined Modality Therapy↗

Benign parotid adenomas: a review of the Princess Margaret Hospital experience.

BACKGROUND: The morbidity of treating benign parotid tumors is an important issue because the majority of patients are young. We therefore undertook this study to evaluate the outcome for these patients treated at the Princess Margaret Hospital. METHODS: A retrospective review was conducted on all patients registered with benign parotid tumors between 1970 and 1987. RESULTS: Seventy-six patients were included in this review; postoperative radiotherapy (XRT) was administered to 55 patients. Median follow-up time was 12.5 years. Postoperative XRT was particularly important for patients with recurrent disease. The risk of both temporary and permanent facial nerve paralyses increased with each operation. No patients in this study developed a malignancy. CONCLUSIONS: We recommend that all patients with benign parotid tumors be treated with a complete parotidectomy with preservation of the facial nerve. Consideration to postoperative XRT should be given to patients in whom there was tumor spillage, residual disease, or recurrences.

Adenoma↗

Situs inversus totalis and corrected transposition of the great arteries [I,D,D] in association with a previously unreported vascular ring.

A 3-month-old girl with "noisy breathing" was found to have situs inversus totalis, corrected transposition of the great arteries [I,D,D], and a vascular ring. The ring was composed of a left aortic arch with normal branching pattern and a right ligamentum arteriosum that extended from a diverticulum off the descending aorta and coursed retroesophageal and to the right to join the pulmonary artery. There was no circumflex component of the aorta or aberrant subclavian artery. The descending aorta was left sided. Compression of the esophagus and trachea was noted on contrast esophagram, magnetic resonance imaging (MRI), and at the time of surgery to divide the vascular ring. In association with her corrected transposition, the patient also was shown to have a mild Ebstein's deformity of the right-sided (systemic) atrioventricular valve and electrocardiographic evidence of Wolfe-Parkinson-White syndrome. The combination of situs inversus totalis, corrected transposition of the great arteries [I,D,D], and an aortic arch anomaly has not been previously reported. In addition, the aortic arch anomaly suggested by MRI imaging and confirmed at surgery has previously only been postulated to exist but to our knowledge never reported.

Echocardiography, Doppler, Color↗

Malignant gastrointestinal stromal tumors of the small intestine: a review of 50 cases from a prospective database.

BACKGROUND: Malignant gastrointestinal stromal tumors (M-GIST) are rare mesenchymal tumors originating in the wall of the gastrointestinal (GI) tract. Previous studies have included limited numbers of patients, and most included malignant and benign cases from throughout the GI tract. We reviewed the experience of a single tertiary cancer care center with M-GIST of the small intestine only. METHODS: A prospective database identified all patients seen from 1989 to 1998. Clinical and pathological data, treatment, and outcome were analyzed. Overall median follow-up time was 24 months (range, 1-176 months). RESULTS: Fifty patients (31 male, 19 female) were identified. Mean age at diagnosis was 55 years. Disease was localized in 11 patients, locally advanced (invasion into adjacent organs/peritoneum) in 24 patients, perforated in 4 patients, multiple primary lesions in 2 patients, and distant metastases in 9 patients. All patients underwent resection, which was complete in 70%. Locoregional recurrence (LR) developed in 43% (median, 25 months), and distant metastases in 59% (median, 21 months) of patients at risk. At last follow-up, 14 patients were alive (6 disease-free), 2 had died disease-free, and 34 died with recurrent disease. Overall survival (OS) was similar for localized and locally advanced disease; OS also was similar for patients with multiple primaries and distant metastases at diagnosis. Patients were grouped into three stages: (I) patients with localized and locally advanced disease; (II) patients with perforated; and (III) patients with multiple primaries and distant metastases. Actuarial OS at 5 years was 41% (n = 50)--42% for those with complete resection and 8% for incomplete resection. Univariable analysis showed that earlier stage at diagnosis (P = .001) and completeness of resection (P = .004) predicted for longer OS. CONCLUSIONS: Most patients with M-GIST of the small intestine relapse following resection, but survival may be prolonged. In univariable analysis, stage at presentation and complete resection were significant prognostic variables for OS; grade was not significant. Localized and locally advanced M-GIST of the small intestine have a mean OS > 5 years. Complete resection should be the goal of initial surgical treatment.

Adult↗

Nasopharyngeal carcinoma: review of how imaging affects staging.

Imaging plays an important role in the staging of carcinoma of the nasopharynx. Accurate staging is necessary as the treatment is directly dependent on stage. Clinical examination provides information on mucosal involvement but is unable to determine the deep extension or presence of skull base invasion or intracranial spread. The 1997 International Union Against Cancer (UICC) and American Joint Committee on Cancer (AJCC) staging manuals were a collaborative project that provided a unified classification for nasopharyngeal carcinoma (NPC). The majority of staging can be identified only on imaging and not by clinical examination. The intent of this article is to provide information on the specific imaging findings that will directly affect the stage and treatment of NPC.

Brain↗

Job stressors and coping strategies as predictors of mental health and job satisfaction among Irish general practitioners.

Previous research has shown that many general practitioners were experiencing stress levels detrimental to their well-being. To examine coping strategies of Irish general practitioners and the possible impact of their stress on mental health and job satisfaction. Anonymous questionnaires were posted to 226 general practitioners in the Western Health Board. Just over one third of stressors caused moderate to considerable stress. Coping was important in the stress process. Sometimes, coping strategies predicted stress-related outcomes better than stressors. General practitioners' mental health was slightly better than that of a normative group. They tended to be satisfied with all aspects of the job, except hours of work. The provision of counselling services for general practitioners suffering from stress should be encouraged. Stress-management strategies should include training in coping skills and time management. The increased use of co-operatives could help alleviate the stress of out-of-hours work.

Adaptation, Psychological↗