PubMed Health⌕ Search

Biomedical subjects

E Chow

Publications and source records attributed to E Chow.

At least 19 recordsLinked to original sources

Phase II study assessing the effectiveness of Biafine cream as a prophylactic agent for radiation-induced acute skin toxicity to the breast in women undergoing radiotherapy with concomitant CMF chemotherapy.

PURPOSE: To assess the efficacy of Biafine cream in preventing Grade 2 acute radiation dermatitis, according to the National Cancer Institute of Canada skin radiation toxicity criteria in patients undergoing concomitant adjuvant chemotherapy and radiotherapy to the breast. METHODS AND MATERIALS: Sixty patients participated in this study. Patients were treated with a lumpectomy followed by concomitant chemotherapy and radiotherapy to the breast. Biafine cream was applied daily, starting on the first day and ending 2 weeks post-radiotherapy. Patients underwent weekly skin assessments throughout radiotherapy and at 2 and 4 weeks after treatment. Outcome measures were assessed using a Skin Assessment Questionnaire that was scored according to the National Cancer Institute of Canada skin radiation toxicity criteria and a self-administered questionnaire that evaluated skin symptoms. RESULTS: The maximum skin toxicity observed during the course of treatment was as follows: less than Grade 2 toxicity, 15% (9 patients); Grade 2, 83% (50 patients); Grade 3, 2% (1 patient); Grade 4, 0% (0 patients). The majority of the radiation dermatitis was observed after 3 weeks of radiotherapy. CONCLUSION: The majority of patients who underwent concomitant chemo- and radiotherapy for breast cancer developed Grade 2 radiation dermatitis with the use of Biafine cream. However, no treatment delays or interruptions were observed because of skin toxicity.

Adult↗

Prospective patient-based assessment of effectiveness of palliative radiotherapy for bone metastases.

PURPOSE: The primary objective of this report is to prospectively evaluate pain control provided by palliative radiotherapy for all irradiated patients with bone metastases by using their own assessments. MATERIALS AND METHODS: A prospective database was set up for all patients referred for palliative radiotherapy for bone metastases. Patients were asked to rate their pain intensity using an 11 categorical point scale (0=lack of pain, 10=worst pain imaginable). Analgesic consumption during the preceding 24 h was recorded and converted into equivalent total daily dose of oral morphine. For those who received radiotherapy, follow-up was conducted via telephone interviews at week 1, 2, 4, 8 and 12 post treatment using the same pain scale and analgesic diary. Radiotherapy outcome was initially assessed by pain score alone. Complete response (CR) was defined as a pain score of 0. Partial response (PR) was defined as a reduction of score > or =2 or a> or =50% reduction of the pre-treatment pain score. We further analyzed outcomes using integrated pain and analgesic scores. Response was defined as either a reduction of pain score > or =2 with at least no increase in analgesics or at least stable pain score with a > or =50% reduction in analgesic intake. RESULTS: One hundred and five patients were treated with palliative radiotherapy. When response evaluation was by pain score alone, the PR rates at 2, 4, 8 and 12 weeks were 44, 42, 30 and 38%, respectively; while the CR rates were 24, 32, 31 and 29%, respectively. The overall response rate at 12 weeks was 67%. When assessed by the integrated pain and analgesic scores, the response rates were 50, 46, 43 and 43%, respectively. CONCLUSION: The response rate in our patient population is comparable with those reported in clinical trials. This is important when counselling our patients on the expected effectiveness of radiotherapy outside of clinical trials. Our observations confirm the generalizability of the trials conducted to date. While randomized trials still remain the gold standard of research, observational studies can serve as useful adjuncts to randomized trials to confirm the efficacy and guide the design of new controlled trials.

Adult↗

Use of the CAGE questionnaire for screening problem drinking in an out-patient palliative radiotherapy clinic.

To determine the positive rate of the CAGE questionnaire in an outpatient palliative radiotherapy clinic and to examine the association between problem drinking, pain control, and analgesic consumption, patients referred for palliative radiotherapy were screened with the CAGE questionnaire and asked to rate their symptom distress using the modified Edmonton Symptom Assessment System (ESAS). The latter instrument uses 11-point numeric scales (0 = best, 10 = worst). Their daily analgesic consumption in oral morphine equivalent was recorded. A total of 128 patients participated in the study. Only 9 patients answered one of the four CAGE questions affirmatively (positive group). All the rest answered negatively (negative group). The mean pain intensity at index site/overall pain was 4.97 +/- 3.31/3.27 +/- 2.76 for the negative group and 6.29 +/- 4.42/2.89 +/- 3.37 for the positive group. The mean total daily oral morphine equivalent for the negative and positive group were 112.35 +/- 233.58 mg and 36.82 +/- 58.85 mg, respectively. There was no significant difference found in other symptoms in the modified ESAS between these two groups. The positive rate of the CAGE in patients with advanced cancer attending an out-patient radiotherapy clinic was only 7%, and analyses were limited by the small sample size of those with a positive CAGE. Whether our observed low positive rate of CAGE represents the true prevalence of problem drinking or the CAGE questionnaire is an insensitive tool for screening problem drinking in an outpatient palliative radiotherapy clinic requires further investigation. We did not find a statistically significant worse pain intensity nor higher analgesic consumption in patients who screened positive for CAGE questionnaire.

Adult↗

Prospective assessment of symptom palliation for patients attending a rapid response radiotherapy program. feasibility of telephone follow-up.

Clinical trials generally include motivated patients with relatively good performance status. This can result in an overestimation of the effectiveness of an intervention. Clinic follow-up protocols for outcome assessment after palliative treatments suffer from high attrition rates. In this study, the feasibility of telephone follow-up for the assessment of symptom palliation in patients receiving outpatient palliative radiotherapy as a tool to evaluate outcome was examined. Patients referred for palliative radiotherapy were asked to rate their symptom distress using the modified Edmonton Symptom Assessment System (ESAS) at initial consultation. Patient demographics and analgesic consumption were collected. For those who received radiotherapy, follow-up was conducted through telephone interviews at week 1, 2, 4, 8, and 12 post-treatment using the same modified ESAS and analgesic diary. One hundred ninety patients received radiotherapy to 256 sites from January to August 1999. Seventy-eight patients (41%) died during the 12-week follow-up period. The percentage of surviving patients responding to the telephone interview ranged from 63% to 68% during the 12-week study. Telephone follow-up is a feasible tool for the prospective outcome assessment of symptom palliation in this population. It compares well to clinic visits or mailed questionnaires. However, to improve the follow-up rates, other modalities may also need to be implemented.

Adult↗

Patients with advanced cancer: a survey of the understanding of their illness and expectations from palliative radiotherapy for symptomatic metastases.

We conducted a pilot study to examine patients' understanding of their illness and their expectations for palliative radiotherapy for symptomatic metastases. Participants were asked to complete a survey consisting of seven questions prior to the initial consultation. Demographic details and information on extent of disease were collected. Patients were asked to score their symptom distress using the modified Edmonton Symptom Assessment System. Sixty patients participated in the pilot study between January and April 1999. Their median age was 68 years (range 46-90). The most common primary tumours were lung, prostate and breast. Twenty-one patients (35%) believed that their cancer was curable. Twelve (20%) expected that palliative radiotherapy would cure their advanced cancer and 23 (38%) believed that palliative radiotherapy would prolong their lives. Twenty-one patients (35%) had concerns about the effectiveness of radiation therapy and twenty (33%) had concerns about the side-effects of radiotherapy. Fifty-two (87%) were not familiar with the concept of radiation treatment. Forty-seven patients (78%) reported that they were not given information about the radiation treatment; 51 (85%) were not satisfied with the information that their own doctors had provided regarding radiation treatment prior to the consultation at our clinic. A significant proportion of the patients in this pilot study had misconceptions regarding their illness and unrealistic expectations from palliative radiotherapy. We plan to provide educational pamphlets for use in referring doctors' surgeries and clinics in order to inform patients of the nature, rationale and anticipated benefits and side-effects of palliative radiotherapy.

Aged↗

How accurate are physicians' clinical predictions of survival and the available prognostic tools in estimating survival times in terminally ill cancer patients? A systematic review.

The purpose of this review was to examine the accuracy of physicians' clinical predictions of survival and the available prognostic tools in estimating survival times in terminally ill cancer patients. A MEDLINE search for English language articles published between 1966 and March 2000 was performed using the following keywords: forecasting/clinical prediction, prognosis/prognostic factors, survival and neoplasm metastasis. Searches in CancerLit, EMBASE, PubMed, the Cochrane Library and reference sections of articles were performed. Studies were included if they concerned adult patients with various cancer histological diagnoses and employed clinical prediction and the readily available clinical parameters. Biochemical and molecular markers were excluded. Grading of the evidence and recommendations was performed. Twelve articles on clinical prediction and 19 on prognostic factors met the inclusion criteria. Clinical prediction tends to be incorrect in the optimistic direction but improves with repeated measurements. Performance status has been found to be most strongly correlated with the duration of survival, followed by the 'terminal syndrome', which includes anorexia, weight loss and dysphagia. Cognitive failure and confusion have also been associated with a shorter life span. Performance status combined with clinical symptoms and the clinician's estimate helps to guide an accurate prediction, as reviewed in an Italian series. There is fair evidence to support using performance status, and clinical and biochemical parameters, in addition to clinicians' judgement to aid survival prediction. However, there is weak evidence to support that clinicians' estimates alone could be specifically employed for survival prediction.

Cognition Disorders↗

A body-mind-spirit model in health: an Eastern approach.

Under the division of labor of Western medicine, the medical physician treats the body of patients, the social worker attends to their emotions and social relations, while the pastoral counselor provides spiritual guidance. Body, mind, cognition, emotion and spirituality are seen as discrete entities. In striking contrast, Eastern philosophies of Buddhism, Taoism and traditional Chinese medicine adopt a holistic conceptualization of an individual and his or her environment. In this view, health is perceived as a harmonious equilibrium that exists between the interplay of 'yin' and 'yang': the five internal elements (metal, wood, water, fire and earth), the six environmental conditions (dry, wet, hot, cold, wind and flame), other external sources of harm (physical injury, insect bites, poison, overeat and overwork), and the seven emotions (joy, sorrow, anger, worry, panic, anxiety and fear). The authors have adopted a body-mind-spirit integrated model of intervention to promote the health of their Chinese clients. Indeed, research results on these body-mind-spirit groups for cancer patients, bereaved wives and divorced women have shown very positive intervention outcomes. There are significant improvements in their physical health, mental health, sense of control and social support.

Adult↗

Three-dimensional control of light in a two-dimensional photonic crystal slab.

Optoelectronic devices are increasingly important in communication and information technology. To achieve the necessary manipulation of light (which carries information in optoelectronic devices), considerable efforts are directed at the development of photonic crystals--periodic dielectric materials that have so-called photonic bandgaps, which prohibit the propagation of photons having energies within the bandgap region. Straightforward application of the bandgap concept is generally thought to require three-dimensional (3D) photonic crystals; their two-dimensional (2D) counterparts confine light in the crystal plane, but not in the perpendicular z direction, which inevitably leads to diffraction losses. Nonetheless, 2D photonic crystals still attract interest because they are potentially more amenable to fabrication by existing techniques and diffraction losses need not seriously impair utility. Here we report the fabrication of a waveguide-coupled photonic crystal slab (essentially a free-standing 2D photonic crystal) with a strong 2D bandgap at wavelengths of about 1.5 microm, yet which is capable of fully controlling light in all three dimensions. These features confirm theoretical calculations on the possibility of achieving 3D light control using 2D bandgaps, with index guiding providing control in the third dimension, and raise the prospect of being able to realize unusual photonic-crystal devices, such as thresholdless lasers.

Journal Article↗

Cutaneous and subcutaneous Ewing's sarcoma: an indolent disease.

PURPOSE: The occurrence of extraosseous Ewing's sarcoma (ES) in deep soft tissues has been well described, but cases in which this tumor occurs in a primary cutaneous or subcutaneous site have rarely been reported. The superficial variant may be less aggressive than are the more common bony and deep soft tissue counterparts with an apparently favorable outcome. A retrospective review of patients with cutaneous or subcutaneous ES was conducted to analyze outcome and patterns of failure. METHODS AND MATERIALS: Between July 1985 and March 1997, 14 patients with cutaneous or subcutaneous ES were treated at St. Jude Children's Research Hospital. The median age at presentation was 16 years (range 7-21 years). Anatomic locations included trunk and pelvis (7), upper or lower extremity (4), and head and neck (3). The median size of the lesion was 3 cm (range, 1-12 cm). Thirteen had definitive surgical resections, and one had biopsy of the mass at the time of referral. They were enrolled on institutional (12) or cooperative group (2) protocols. All patients received chemotherapy, composed of vincristine, doxorubicin, cyclophosphamide, ifosfamide, etoposide, and dactinomycin. Patients on institutional protocols received radiation (36 Gy) to the operative bed (150-180 cGy/fraction/day). Postoperative radiotherapy was omitted for 2 patients who had complete resection on the cooperative group study. RESULTS: No patients had metastatic disease at presentation. Thirteen patients had wide local excision of the primary tumors prior to enrollment on chemotherapy; surgical margins were negative (10), microscopically positive (2), and indeterminate (1). Eleven patients received radiotherapy to the tumor bed; 2 with clear surgical margins were treated without irradiation. The patient who had biopsy only received induction chemotherapy followed by definitive surgical resection and postoperative radiotherapy. The median follow-up was 77 months (range 17-111 months). None of the patients has developed local recurrence or distant metastasis. Several of the patients developed treatment-related sequelae, including veno-occlusive disease of the lung and hemorrhagic cystitis (1), myelodysplastic syndrome (1), chemotherapy-induced ovarian failure (1), moist desquamation (1), and dermatofibroma within the radiotherapy volumes (1). CONCLUSIONS: Cutaneous and subcutaneous ES are associated with an indolent course and a favorable prognosis when treated with combined modality therapy. Elimination of radiation therapy following complete resection has been tested in the POG 9354 trial. The high rate of local control, low rate of metastatic disease, and excellent overall outcome may suggest a role for less intensive chemotherapy, as well as tailoring to diminish or avoid radiation therapy in completely resected cases, with a goal to minimize toxicity while maintaining a high cure rate.

Adolescent↗

Referring physicians' satisfaction with the rapid response radiotherapy programme. Survey results at the Toronto-Sunnybrook Regional Cancer Centre.

For patients with advanced incurable cancer, radiotherapy provides effective palliation and improved quality of life. At the Toronto-Sunnybrook Regional Cancer Centre, the Rapid Response Radiotherapy Programme, a pilot programme in Ontario, was started in 1996 to provide timely palliative radiotherapy. Over 200 patients have been seen annually since 1996. Of the patients referred to the clinic, 90% were treated by palliative radiotherapy. Of those requiring radiotherapy, 80% received treatment on the day of their initial visits, and 90% of the irradiated patients received one to five treatments. The programme has been warmly welcomed by many community medical oncologists and palliative care consultants. Other centres in Canada have followed our example and set up similar clinics. We sent out a survey to all referring physicians to explore the strengths and weaknesses of our programme so as to improve our services. There has been an increase in the utilization of palliative radiotherapy because of the availability of our programme. As a result of this survey we corrected some of our deficiencies. We plan to survey our patients' needs and satisfaction to further improve our programme, since the patients are the ultimate consumers of the service.

Adult↗

Palliation of bone metastases: a survey of patterns of practice among Canadian radiation oncologists.

BACKGROUND: Palliative radiotherapy constitutes nearly 50% of the workload in radiotherapy. Surveys on the patterns of practice in radiotherapy have been published from North America and Europe. Our objective was to determine the current pattern of practice of radiation oncologists in Canada for the palliation of bone metastases. METHOD: A survey was sent to 300 practicing radiation oncologists in Canada. Five case scenarios were presented. The first three were patients with a single symptomatic site: breast cancer patient with pelvic metastasis, lung cancer male with metastasis to L3 and L1, respectively. The last two were breast and prostate cancer patients with multiple symptomatic bone metastases. RESULTS: A total of 172 questionnaires were returned (57%) for a total of 860 responses. For the three cases with a single painful bone metastasis, over 98% would prescribe radiotherapy. The doses ranged from a single 8 to 30 Gy in ten fractions. Of the 172 respondents, 117 (68%) would use the same dose fractionation for all three cases, suggesting that they had a standard dose fractionation for palliative radiotherapy. The most common dose fractionation was 20 Gy in five fractions used by 84/117 (72%), and 8 Gy in one fraction by 19/117 (16%). In all five case scenarios, 81% would use a short course of radiotherapy (single 8 Gy, 17%; 20 Gy in five fractions, 64%), while 10% would prescribe 30 Gy in ten fractions. For the two cases with diffuse symptomatic bone metastases, half body irradiation (HBI) and radionuclides were recommended more frequently in prostate cancer than in breast cancer (46/172 vs. 4/172, P<0. 0001; and 93/172 vs. 10/172, P<0.0001, respectively). Strontium was the most commonly recommended radionuclide (98/103=95%). Since systemic radionuclides are not readily available in our health care system, 41/98 (42%) of radiation oncologists who would recommend strontium were not familiar with the dose. Bisphosphonates were recommended more frequently in breast cancer than in prostate cancer 13/172 (8%) vs. 1/172 (0.6%), P=0.001. CONCLUSION: Local field external radiotherapy remains the mainstay of therapy, and the most common fractionation for bone metastases in Canada is 20 Gy in five fractions compared with 30 Gy in ten fractions in the US. Despite randomized trials showing similar results for single compared with fractionated radiotherapy, the majority of us still advocate five fractions. The frequency of employing a single fractionation has not changed since the last national survey in 1992. Nearly 70% use a standard dose fractionation to palliate localized painful metastasis by radiotherapy, independent of the site of involvement or tumor type. The pattern of practice of palliative radiotherapy for bone metastases in Canada is different to that reported previously from the US. The reasons why the results of randomized studies on bone metastases have no impact on the patterns of practice are worth exploring.

Bone Neoplasms↗

Lipid and giant cell poor necrobiotic xanthogranuloma.

An 88-year-old man over a 7-month period developed multiple yellow firm focally ulcerative papules and nodules over his face, neck and forearms. Seven skin biopsies showed a diffuse infiltrate of epithelioid histiocytes associated with areas of necrosis with neutrophilia. Two biopsies showed xanthogranulomatous foci, but cholesterol clefts, prominent giant cells or lymphoid aggregates were not evident. Necrosis with leukocytoclastic debris overshadowed the presence of hyaline necrobiosis. Ultrastructural examination and oil red-o stains on frozen sections revealed focal lipid vacuoles within histiocytes. A paraprotein was detected in the patient's serum. This presentation may represent a lipid and giant cell poor variant of necrobiotic xanthogranuloma (NXG) and may potentially lead to a delay in diagnosis.

Aged↗

Long term outcome and cost in the management of stage I testicular seminoma.

PURPOSE: To validate the use of surveillance as an alternative to adjuvant RT in clinical stage I seminoma, we analyzed our experience with the two approaches in terms of long term outcome and cost. PATIENTS AND METHODS: Between January 1981 and December 1994, 471 patients with stage I testicular seminoma were treated at our institution. Of these, 245 patients received post-operative RT (25 Gy) to the retroperitoneal lymph nodes, and 226 have been managed with surveillance following orchidectomy. Two patients were included in this series twice; both had RT previously for seminoma, were placed on surveillance for a contralateral seminoma and were analyzed for outcome of both primary tumors. The costs associated with both approaches were estimated in 1994 Canadian dollars (C$). RESULTS: With a median follow-up of 7.7 years in the surveillance patients, and 9.7 years in the adjuvant RT cohort, the 5 year actuarial survival for all patients was 97% and the cause-specific survival (CSS) was 99.8%. Of the 226 patients on surveillance 37 patients have relapsed to date; five of those developed a second relapse. One patient has died of disease. Of the 245 patients treated with adjuvant RT, 14 patients have relapsed and none had a second relapse. The CSS was 100%. Thirteen patients on surveillance (5.7%) and 10 patients treated with post-operative RT (4.1%) have received chemotherapy as part of their management. One hundred and eighty-nine patients on surveillance have received no post-orchidectomy treatment to date. Surveillance was more expensive with an average additional cost per patient per year of Can$2620 over 10 years. CONCLUSIONS: Both adjuvant RT and surveillance give excellent results in stage I seminoma. The documented increased risk of second malignant tumors following RT must be taken into account when considering the additional cost of surveillance. The routine use of post-operative RT in stage I seminoma should be reconsidered and a surveillance program offered to all patients as an alternative management option.

Actuarial Analysis↗

Pediatric choroid plexus neoplasms.

PURPOSE: Choroid plexus tumors (CPT) are rare childhood neoplasms. The relatively small number of reported cases and the controversies surrounding the clinical and pathological classification of these tumors have made it difficult to define a standard of care for these patients. Our intention is to contribute to the body of knowledge of these tumors and further define the role of adjuvant therapy. METHODS AND MATERIALS: We performed a retrospective review of 14 children with choroid plexus neoplasms referred to St. Jude Children's Research Hospital between October 1985 and December 1987. Ten patients had choroid plexus carcinoma (CPC) based on pathologic criteria and evidence of brain invasion at surgery or leptomeningeal disease (M+); 4 patients had choroid plexus papilloma (CPP). Patients with CPP were initially treated with surgery alone whereas patients with CPC were generally treated with postoperative therapy that included chemotherapy (CT) and/or craniospinal irradiation (CSI) with a focal boost to the primary site. For most patients CT consisted of combinations of cyclophosphamide, etoposide, vincristine, and a platinum agent. The median CSI dose was 35.2 Gy (range 24-46.2 Gy). The median primary site dose was 55.2 Gy (range 49.6-64 Gy). RESULTS: Seven of the 10 CPC cases presented with leptomeningeal dissemination; two of these patients have succumbed to disease. Of the 3 patients with M0 status, all are alive with no evidence of disease (NED). The medial time to relapse from the time of surgery was 5.3 mo (range 3-25 mo). Seven CPC patients were treated with gross total resection (GTR). Three of these patients (2 M0, 1 M+) received CT without CSI and are currently NED (27, 69, and 60 mo respectively). One M+ patient progressed on CT and has stable disease after CSI (6 mo), one (M0) received CT and CSI and is NED (120 mo), one (M+) is currently on CT with objective response (3 mo) and one (M+) died of progressive disease (24.5 mo) despite CT and CSI. Three patients with CPC had subtotal resection (STR). One of these patients (M+) received CT and CSI and is NED (23 mo), one (M0) had an elective second resection GTR alone and is currently NED (153 mo), and one (M+) developed progressive disease (13.5 mo) while on CT and died despite CSI. Among the 4 CPP patients, GTR was performed in two; both were NED at 54 and 81 mo. Two patients with CPP (one with focal atypia) were treated with STR initially; both transformed to CPC at 7 and 27 mo, respectively. Both were currently NED following salvage with (1) GTR and CSI alone (98 mo) or (2) STR, CT, and CSI (62 mo). Six of the 12 survivors in this series had significant neuropsychological sequelae. CONCLUSION: The prognosis of CPP is good for patients treated with GTR. Malignant transformation occurred in 2 CPP patients with less than GTR. Patients with localized CPC who undergo GTR have had a favorable outcome with the addition of chemotherapy or irradiation. CSI may not be routinely indicated in M0 children following GTR. There is evidence that salvage with radiation therapy may be successful following progression on chemotherapy. For patients treated with STR, the use of CT and CSI appears to be necessary.

Adolescent↗

Dual-site binding of bivalent 4-aminopyridine- and 4-aminoquinoline-based AChE inhibitors: contribution of the hydrophobic alkylene tether to monomer and dimer affinities.

Three series of 4-aminopyridine-and 4-aminoquinoline based symmetrical bivalent acetylcholinesterase (AChE) inhibitors were prepared and compared to previously synthesized dimers of 9-amino-1,2,3,4-tetrahydroacridine (tacrine). In each case significant, tether length-dependent increases in AChE inhibition potency and selectivity (up to 3000-fold) were observed relative to the corresponding monomer, indicating dual-site binding of these inhibitors to AChE. Assay of the corresponding alkylated monomers revealed that the alkylene tether played at least two complementary roles in the dimer series. In addition to reducing the entropy loss that occurs on binding both monomeric units of the dimer, the alkylene tether can also significantly improve potency through hydrophobic effects.

4-Aminopyridine↗

Malignant evolution of choroid plexus papilloma.

Choroid plexus tumors are rare CNS neoplasms. The distinction between choroid plexus papilloma (CPP) and choroid plexus carcinoma (CPC) is made on the basis of clinical and histological criteria. Malignant evolution of CPP may occur, and the presence of mitotic figures in CPP may predict the likelihood of recurrence or malignant evolution. Close surveillance is mandated for these patients. We report on two such cases of CPP that transformed to CPC at the time of recurrence.

Cell Transformation, Neoplastic↗