PubMed Health⌕ Search

Biomedical subjects

David McCready

Publications and source records attributed to David McCready.

9 recordsLinked to original sources

Systematic review of systemic adjuvant therapy for patients at high risk for recurrent melanoma.

The authors examined the role of systemic adjuvant therapy in patients with high-risk, resected, primary melanoma. Outcomes of interest included overall survival, disease-free survival, adverse effects, and quality of life. A systematic review of the literature was conducted to locate randomized controlled trials, practice guidelines, meta-analyses, and reviews published between 1980 and 2004. Thirty-seven randomized controlled trials, 2 meta-analyses, and 1 systematic review were identified that investigated interferon, levamisole, vaccine, or chemotherapy as adjuvant therapy. For high-dose interferon-alpha, the results from 3 randomized trials conducted by the Eastern Cooperative Oncology Group were pooled, and a meta-analysis of 2-year death rates yielded a risk ratio of 0.85 (95% confidence interval, 0.73-0.99; P = .03). Five randomized trials comparing low-dose interferon-alpha with observation only after surgery did not detect a statistically significant improvement in overall survival. A meta-analysis of 4 levamisole trials did not demonstrate a significant survival benefit for levamisole over control; similarly, no survival benefit was demonstrated by data from randomized controlled trials with vaccines (9 trials) or with chemotherapy (10 trials). In this review of the available literature, no systemic adjuvant therapy was identified that conferred a significant overall survival benefit in patients with high-risk, resected, primary melanoma. However, high-dose interferon should be considered in the treatment of these patients, because such therapy is associated with a significant improvement in disease-free survival and a reduction in 2-year mortality. Until the results of ongoing trials are available, the authors could not state with confidence whether such therapy benefits patients with microscopically detected, sentinel lymph node-positive disease.

Adjuvants, Immunologic↗

A case of axillary web syndrome with subcutaneous nodules following axillary surgery.

Axillary web syndrome (AWS) is a cause of morbidity in the early postoperative period following axillary surgery, which is characterized by cords of subcutaneous tissue extending from the axilla into the medial arm. Few reports have been published describing this entity, which results in pain and a limitation of shoulder abduction. Here, we report a case of AWS that was accompanied with sub-cutaneous nodules mimicking recurrence of breast cancer.

Adult↗

Sentinel lymph node biopsy for cutaneous melanoma of the head and neck.

BACKGROUND: Lymph node status is the most important prognostic factor for patients with cutaneous melanoma. Sentinel lymph node biopsy (SLNB) is now the standard of care for staging clinically node-negative patients. It is accurate with low morbidity, yet SLNB for head and neck melanoma is challenging because of unpredictable lymphatic drainage and risk of complications. METHODS: A retrospective analysis of prospectively collected data identified patients with cutaneous melanoma of the head and neck > or =.76 mm. Sentinel lymph nodes were identified by using a standardized protocol of preoperative lymphoscintigrams, intraoperative blue dye injections, and handheld gamma probes. Clinical, surgical, and pathologic data were collected and analyzed. RESULTS: A sentinel lymph node was removed in 41 (94%) of 44 patients. Seven (17%) of 41 had at least 1 positive sentinel lymph node. Three of seven had primary tumors <1 mm (two of the three were not ulcerated). The sites of lymphatic drainage of the primary lesion were discordant, with historical anatomically predicted sites in 24.4% of cases. None of the 34 patients with negative SLNB has had a nodal recurrence (false-negative rate, 0%; sensitivity and negative predictive value, 100%). The mean follow-up is 22.4 months (range, <1-69 months). Seven (17%) of 41 patients had minor complications. CONCLUSIONS: SLNB in the head and neck area is challenging; however, combined preoperative, intraoperative, and histological techniques produce a sensitive procedure with a high negative predictive value. The lack of false-negative results obviates the need for prophylactic neck dissections.

Adult↗

Surgical management of early stage invasive breast cancer: a practice guideline.

OBJECTIVES: To assess the available evidence on sentinel lymph-node biopsy, and to examine the long-term follow-up data from large randomized phase III trials comparing breast-conserving therapy with mastectomy in order to make recommendations on the surgical management of early invasive breast cancer (stages I and II), including the optimum management of the axillary nodes: for the breast--modified radical mastectomy or breast-conserving therapy; for the axilla--complete axillary node dissection, axillary dissection of levels I and II lymph nodes, sentinel lymph-node biopsy or no axillary node surgery. OUTCOMES: Overall survival, disease-free survival, local recurrence, distant recurrence and quality of life. EVIDENCE: MEDLINE, EMBASE, the Cochrane Library databases and relevant conference proceedings were searched to identify randomized trials and meta-analyses. Two members of the Practice Guidelines Initiative, Breast Cancer Disease Site Group (BCDSG) selected and reviewed studies that met the inclusion criteria. The systematic literature review was combined with a consensus process for interpretation of the evidence to develop evidence-based recommendations. This practice guideline has been reviewed and approved by the BCDSG, comprising surgeons, medical oncologists, radiation oncologists, pathologists, a medical sociologist, a nurse representative and a community representative. BENEFITS, HARMS AND COSTS: Breast-conserving therapy (lumpectomy with levels I and II axillary node dissection, plus radiotherapy) provides comparable overall and disease-free survival to modified radical mastectomy. Levels I and II axillary dissection accurately stages the axilla and minimizes the morbidity of axillary recurrence but is associated with lymphedema in approximately 20% of patients and arm pain in approximately 33%. Currently, there is insufficient data regarding locoregional recurrence and long-term morbidity associated with sentinel-node biopsy to advocate it as the standard of care. Breast-conserving therapy may offer an advantage over mastectomy in terms of body image, psychological and social adjustment but appears equivalent with regard to marital adjustment, global adjustment and fear of recurrence. RECOMMENDATIONS: Women who are eligible for breast-conserving surgery should be offered the choice of either breast-conserving therapy with axillary dissection or modified radical mastectomy. Removal and pathological examination of levels I and II axillary lymph nodes should be the standard practice in most cases of stages I and II breast carcinoma. There is promising but limited evidence to support recommendations regarding sentinel lymph-node biopsy alone. Patients should be encouraged to participate in clinical trials investigating this procedure. VALIDATION: A draft version of this practice guideline and a 21-item feedback questionnaire was circulated to 201 practitioners in Ontario. Of the 131 practitioners who returned the questionnaire, 98 (75%) completed the survey and indicated that the report was relevant to their clinical practice. Eighty (82%) of these practitioners agreed that the draft document should be approved as a practice guideline.

Breast Neoplasms↗

Breast tissue organochlorine levels and metabolic genotypes in relation to breast cancer risk Canada.

Genes that metabolize the rate of clearance of environmental carcinogens may be candidate genes for cancer susceptibility. There is some data to suggest that exposure to environmental pesticides and other organochlorine pollutants is a risk factor to breast cancer. It is therefore reasonable to ask if variants in the genes responsible for the metabolic activation of organochlorines are associated with different tissue burdens of organochlorines and if these variants modify the risk of breast cancer in the population. We conducted a case-control study of women who underwent an excision biopsy for suspected breast cancer in a Toronto hospital from 1995 to 1997. Patients are residents of the Greater Toronto Area and are primarily Caucasian of European descent. Cases were women with invasive breast cancer (n = 70) and controls (n = 69) were women diagnosed with benign disease, frequency matched by age to cases. Levels of organochlorines were measured in benign breast tissue and seven polymorphisms in five candidate genes were genotyped. In general, women who carried inactive alleles of the GSTM1 had higher levels of breast organochlorines, and were at modestly increased risk of breast cancer (odds ratio = 2.2; 95% CI = 1.1-4.4). However, multiple comparisons were made and generally our data do not support the hypothesis that organochlorines increase the risk of breast cancer among subgroups of women with specific metabolic genotypes.

Adult↗

Development and evaluation of sentinel node biopsy: a continuing professional development course.

The Interpretive Visualization (IVIS) Group at the Division of Biomedical Communications, Dept. of Surgery, University of Toronto has developed a visually-oriented, Internet-based Continuing Professional Development (CPD) course on Sentinel Node Biopsy. The site design methodology involved an extensive needs assessment, iterative formative evaluations of site and media design, a summative evaluation of the project, and a final evaluation for certification. Special emphasis was placed on asynchronous Web-based evaluation of the visual media-including still images, animations, and interactive figures-used in the course. Results reinforced the importance of: needs assessment; a user-centered design process; and rapid prototyping.

Clinical Competence↗

Biology of lymphatic metastases in breast cancer: lessons learned from sentinel node biopsy.

BACKGROUND: The evolution of sentinel node biopsy has placed new emphasis on the biology of lymphatic metastases in breast cancer. If radiocolloid mimics the migration of tumor cells, the nodes with the most uptake should also be the most likely to harbor metastatic cells. We attempted to correlate the frequency of metastatic disease to the greatest gamma uptake and to clarify the physiology of breast lymphatic drainage. METHODS: Data were collected from 152 patients undergoing sentinel node biopsy from January 1997 to June 1999. Localization was by injection of unfiltered (99m)Tc-labeled sulfur colloid. Sentinel nodes were identified with an intraoperative gamma counter and the 10% rule. A completion level I/II axillary dissection was performed in all patients. RESULTS: Fifty-four of 152 patients were positive for metastatic disease. There were no false-negative sentinel nodes. In 46 (85%) of 54 cases, the node with the highest uptake was positive for metastatic disease. In the remaining eight (15%) cases, another node with a lower gamma count was positive. CONCLUSIONS: The sentinel node with the highest uptake is not the one that contains metastatic disease in 15% of cases. This may reflect variations in lymphatic channels or technical variations in colloid properties and injection technique.

Adult↗

Stress response syndromes in women undergoing mammography: a comparison of women with and without a history of breast cancer.

OBJECTIVE: The purpose of this study was to assess the incidence, severity, and correlates of acute stress responses in women undergoing diagnostic mammographic surveillance and to explore the moderating impact of physician support on these symptoms. METHODS: Sixty-six female breast cancer outpatients (at least 12 months after diagnosis and primary treatment) and 69 healthy women undergoing mammographic surveillance completed measures of: acute stress response, somatization, trauma history, psychiatric history, social support, and physician satisfaction. RESULTS: Previous cancer, pre-mammography breast complaints, lower income, previous psychiatric medication use, greater instrumental support, greater somatization, greater perceived physician disengagement, and less perceived physician support were all associated with increased stress responses. Among women with a previous cancer diagnosis, those with greater distress reported higher levels of physician support. In contrast, among those without a previous cancer diagnosis, those with greater perceived physician support reported less distress. CONCLUSIONS: These findings suggest that cancer-related cues, such as follow-up surveillance, may trigger a sensitizing response in women with a previous cancer diagnosis. The association of distress with physician support may arise from the responsiveness of physicians to identified distress, from increased help-seeking behavior by those who are distressed, or both. The benefit of support provided by health care professionals to those at risk of developing stress response syndromes deserves further study.

Acute Disease↗