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Lisa Barbera

Publications and source records attributed to Lisa Barbera.

11 recordsLinked to original sources
PubMed2006

The rapid uptake of concurrent chemotherapy for cervix cancer patients treated with curative radiation.

PURPOSE: In 1999, a series of clinical trials along with a clinical announcement from the National Cancer Institute (NCI) suggested that chemotherapy should be used concurrently with pelvic radiation in the management of cervical cancer. The purpose of this study is to examine the rate of chemotherapy use, in the province of Ontario, before and after these publications. METHODS: All incident cases of cervix cancer diagnosed between January 1, 1995, and March 31, 2001, were identified using the provincial cancer registry. These records were electronically linked to billing claims data and inpatient discharge abstract data. Patients receiving brachytherapy within 6 months of diagnosis were identified. The proportion receiving at least one injection of chemotherapy before brachytherapy was identified and compared in the "pre" and "post" publication group (April 1, 1999, cutoff). RESULTS: We identified 1039 cases as receiving curative radiation. In the pre cohort, 9.4% of patients received chemotherapy (95% CI, 7.3-11.4%) vs. 67.4% in the post cohort (95% CI, 61.8-73.0%). The change occurred abruptly in the first quarter of 1999. CONCLUSION: There was a significant increase in chemotherapy use after the publication of the NCI alert and related trials. Reasons for rapid uptake are discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2006

Indicators of poor quality end-of-life cancer care in Ontario.

This study measures the proportion of cancer patients in Ontario, Canada, with intensive care unit (ICU) admissions, emergency room (ER) visits, or chemotherapy in the last two weeks of life. We used the Ontario Cancer Registry to identify a cohort of cancer patients who died in 2001. These cases were then linked to administrative sources of data to measure each indicator, and to describe the associated clinical and health service factors. In the cohort, 27% had at least one ER visit and 5% had an ICU visit in the last two weeks of life. Of those who received chemotherapy in the last six months, 16% received chemotherapy in the last two weeks of life. Receiving a home care visit in the last six months of life, or a physician house call or a palliative care assessment in the last two weeks of life was consistently associated with decreased odds of each of the indicators. Our results indicate that a significant proportion of Ontario cancer patients have indicators of poor quality end-of-life care. Certain health care factors may influence these indicators.

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PubMed2005

Use of CT simulation for treatment of cervical cancer to assess the adequacy of lymph node coverage of conventional pelvic fields based on bony landmarks.

PURPOSE: To assess the adequacy of nodal coverage of "conventional" pelvic radiation fields for carcinoma of the cervix, with contoured pelvic vessels on simulation computed tomography (CT) as surrogates for lymph node location. METHODS AND MATERIALS: Pelvic arteries were contoured on non-contrast-enhanced CT simulation images of 43 patients with cervix cancer, FIGO Stages I-III. Vessel contours were hidden, and conventional pelvic fields were outlined: (1) anterior/posterior fields (AP): superior border, L5-S1 interspace; inferior border, obturator foramina; lateral border, 2 centimeters lateral to pelvic brim. (2) Lateral fields (LAT): Anterior border, symphysis pubis; posterior border, S2-S3 interspace. Distances were measured between the following: (1) bifurcation of the common iliac artery and superior border, (2) external iliac artery and lateral border of the AP field, and (3) external iliac artery and anterior border of the LAT field. The distances were considered as "inadequate" if <15 mm, "adequate" if 15-20 mm, and "generous" if >20 mm. RESULTS: Superiorly, 34 patients (79.1%) had inadequate coverage. On the AP, margins were generous in 19 (44.2%), but inadequate in 9 (20.9%). On the LAT, margins were inadequate in 30 (69.8%) patients. Overall, 41 (95.4%, CI, 84.2%-99.4%) patients had at least 1 inadequate margin, the majority located superiorly. Twenty-four (55.8%; CI, 39.9%-70.9%) patients had at least 1 generous margin, the majority located laterally on the AP field. CONCLUSION: Conventional pelvic fields based on bony landmarks do not provide optimal lymph node coverage in a substantial proportion of patients and may include excess normal tissue in some. CT simulation with vessel contouring as a surrogate for lymph node localization provides more precise and individualized field delineation.

Feasibility Studies↗
PubMed2004

Estimating the benefit and cost of radiotherapy for lung cancer.

PURPOSE: To estimate the benefit and cost of using radiotherapy (RT) in the initial management of lung cancer in the general population. METHODS: We identified indications for RT in the initial management of small cell and non-small cell lung cancer through a review of the literature. The proportion of patients with each specific indication for treatment was determined using epidemiological observations from cancer registry data and from the literature. We estimated the benefit gained from RT use for each indication in the model using values published in the literature. We estimated the cost of RT for each indication using published Canadian data. The total benefit and cost was calculated for all indications combined. Results are reported in 2001 Canadian dollars. RESULTS: The mean benefit was 7 months of survival for each lung cancer patient treated with curative intent and 3 months of symptom control for each patient treated with palliative intent. The average cost was 9881 dollars per life year gained and 13,938 dollars per year of symptom control gained. Sensitivity analysis revealed values between 7905 dollars and 19,762 dollars per year of survival gain and between 10,368 dollars and 27,875 dollars per year of symptom control gained. CONCLUSIONS: Using RT in the initial management of lung cancer can provide considerable gains in survival and symptom control. The cost of RT for the initial management of lung cancer is inexpensive compared with a common cut off of 50,000 dollars per life year gained.

Cost-Benefit Analysis↗
PubMed2003

An evidence-based estimate of the appropriate radiotherapy utilization rate for colorectal cancer.

PURPOSE: Current estimates of the proportion of cancer patients who will require RT are based almost entirely on expert opinion. The objective of this study was to estimate the proportion of incident cases of colorectal cancer that should receive RT using an evidence-based approach. METHODS AND MATERIALS: A systematic review of the literature was undertaken to identify indications for RT for colorectal cancer, and to ascertain the level of evidence that supported each indication. An epidemiologic approach was then used to estimate the incidence of each indication for RT in a typical North American population of colorectal cancer patients. The effect of sampling error on the estimated appropriate rate of RT was calculated mathematically, and the effect of systematic error was estimated by sensitivity analysis. RESULTS: It was estimated that 23.7% +/- 1.0% of colorectal cancer cases develop one or more indications for RT at some point in the course of the illness: 20.9% +/- 1.1% as part of their initial treatment, and 2.8% +/- 0.5% later for recurrence or progression. We estimated that 7.1% +/- 0.8% of colon carcinoma patients will require RT at some point in the course of the illness: 4.0% +/- 0.7% as part of their initial treatment, and 3.1% +/- 0.4% later for recurrence or progression. We estimated that 72.3% +/- 1.0% of rectal carcinoma patients will require RT at some point in the course of the illness: 69.6% +/- 0.9% as part of their initial treatment and 2.7% +/- 0.2% later for recurrence or progression. CONCLUSIONS: This method provides a rational starting point for the long-term planning of radiation services, and for the audit of access to RT at the population level. By completing such evaluations in the major cancer sites, it will be possible to estimate the appropriate RT treatment rate for the cancer population as a whole.

Colonic Neoplasms↗
PubMed2003

Performance of different radiotherapy workload models.

PURPOSE: The purpose of this study was to evaluate the performance of different radiotherapy workload models using a prospectively collected dataset of patient and treatment information from a single center. METHODS AND MATERIALS: Information about all individual radiotherapy treatments was collected for 2 weeks from the three linear accelerators (linacs) in our department. This information included diagnosis code, treatment site, treatment unit, treatment time, fields per fraction, technique, beam type, blocks, wedges, junctions, port films, and Eastern Cooperative Oncology Group (ECOG) performance status. We evaluated the accuracy and precision of the original and revised basic treatment equivalent (BTE) model, the simple and complex Addenbrooke models, the equivalent simple treatment visit (ESTV) model, fields per hour, and two local standards of workload measurement. RESULTS: Data were collected for 2 weeks in June 2001. During this time, 151 patients were treated with 857 fractions. The revised BTE model performed better than the other models with a mean [observed -predicted] of 2.62 (2.44-2.80). It estimated 88.0% of treatment times within 5 min, which is similar to the previously reported accuracy of the model. CONCLUSION: The revised BTE model had similar accuracy and precision for data collected in our center as it did for the original dataset and performed the best of the models assessed. This model would have uses for patient scheduling, and describing workloads and case complexity.

Appointments and Schedules↗
PubMed2003

Does delay in starting treatment affect the outcomes of radiotherapy? A systematic review.

PURPOSE: The objective of this study was to synthesize what is known about the relationship between delay in radiotherapy (RT) and the outcomes of RT. METHODS: A systematic review of the world literature was conducted to identify studies that described the association between delay in RT and the probability of local control, metastasis, and/or survival. Studies were classified by clinical and methodologic criteria and their results were combined using a random-effects model. RESULTS: A total of 46 relevant studies involving 15,782 patients met our minimum methodologic criteria of validity; most (42) were retrospective observational studies. Thirty-nine studies described rates of local recurrence, 21 studies described rates of distant metastasis, and 19 studies described survival. The relationship between delay and the outcomes of RT had been studied in diverse situations, but most frequently in breast cancer (21 studies) and head and neck cancer (12 studies). Combined analysis showed that the 5-year local recurrence rate (LRR) was significantly higher in patients treated with adjuvant RT for breast cancer more than 8 weeks after surgery than in those treated within 8 weeks of surgery (odds ratio [OR] = 1.62, 95% confidence interval [CI], 1.21 to 2.16). Combined analysis also showed that the LRR was significantly higher among patients who received postoperative RT for head and neck cancer more than 6 weeks after surgery than among those treated within 6 weeks of surgery (OR = 2.89; 95% CI, 1.60 to 5.21). There was little evidence about the impact of delay in RT on the risk of metastases or the probability of long-term survival in any situation. CONCLUSION: Delay in the initiation of RT is associated with an increase [corrected] in LRR in breast cancer and head and neck cancer. Delays in starting RT should be as short as reasonably achievable.

Breast Neoplasms↗
PubMed2003

Evidence-based estimate of appropriate radiotherapy utilization rate for prostate cancer.

PURPOSE: Current estimates of the proportion of cancer patients who will require radiotherapy (RT) are based almost entirely on expert opinion. The objective of this study was to use an evidence-based approach to estimate the proportion of incident cases of prostate cancer that should receive RT at any point in the evolution of the illness. METHODS AND MATERIALS: A systematic review of the literature was undertaken to identify indications for RT for prostate cancer and to ascertain the level of evidence that supported each indication. An epidemiologic approach was then used to estimate the incidence of each indication for RT in a typical North American population of prostate cancer patients. The effect of sampling error on the estimated appropriate rate of RT was calculated mathematically, and the effect of systematic error using alternative sources of information was estimated by sensitivity analysis. RESULTS: It was estimated that 61.2% +/- 5.6% of prostate cancer cases develop one or more indications for RT at some point in the course of the illness. The plausible range for this rate was 57.3%-69.8% on sensitivity analysis. Of all prostate cancer patients, 32.2% +/- 3.8% should receive RT in their initial treatment and 29.0% +/- 4.1% later for recurrence or progression. The proportion of cases that ever require RT is risk grouping dependent; 43.9% +/- 2.2% in low-risk disease, 68.7% +/- 3.5% in intermediate-risk disease; and 79.0% +/- 3.8% in high-risk locoregional disease. For metastatic disease, the predicted rate was 66.4% +/- 0.3%. CONCLUSION: This method provides a rational starting point for the long-term planning of radiation services and for the audit of access to RT at the population level. By completing such evaluations in major cancer sites, it will be possible to estimate the appropriate RT rate for the cancer population as a whole.

Humans↗
PubMed2003

Defining the need for radiotherapy for lung cancer in the general population: a criterion-based, benchmarking approach.

BACKGROUND: We have previously used an evidence-based, epidemiologic approach to estimate the proportion of incident cases that should be treated with radiotherapy (RT) for lung cancer. The first objective of the present study was to compare this evidence-based estimate of the appropriate rate of use of RT with the rates observed in selected "benchmark" communities where there are no barriers to the appropriate use of RT and no incentives to the unnecessary use of RT. The second objective of the study was to compare the rates of use of RT in the general populations in the United States and Canada with the estimated appropriate rate. METHODS: We established benchmark rates for the use of RT for lung cancer in Ontario, Canada, where: 1) residents make no direct payments for RT; 2) all RT is provided by site-specialized radiation oncologists in multidisciplinary cancer centers, and 3) radiation oncologists receive a salary in lieu of technical fees. Communities located close to cancer centers without long waiting lists for RT were selected to serve as benchmarks. Prospectively gathered electronic treatment records from all RT cancer centers were linked to the provincial cancer registry to describe the rate of use of RT in Ontario. The public use file of Surveillance, Epidemiology and End Results Registries (SEER) was used to describe the use of RT in the United States. RESULTS: Overall, 41.3% (95% confidence interval [CI], 39.9%, 42.7%) of incident cases of lung cancer received RT as part of their initial management in the benchmark communities compared with the evidence-based estimate of 41.6% (95% CI, 39.2%, 44.1%). The rate of use of RT in the initial management of nonsmall cell lung cancer (NSCLC) in the benchmark communities was 49.3% (95% CI, 47.5%, 51.1%) compared with the evidence-based estimate of 45.9% (95% CI, 41.6%, 50.2%). The use of RT in the initial management of small-cell lung cancer (SCLC) in the benchmark communities was 47.0% (95% CI, 43.3%, 50.7%) compared with the evidence-based estimate of 45.4% (95% CI, 42.4%, 48.4%). In many counties of Ontario, the observed rates of RT use in the initial management of lung cancer were significantly lower than either the benchmark rate or the evidence-based estimate of the appropriate rate. In contrast, rates of use of RT in most counties in the SEER regions of the United States were close to, or higher than, the estimated appropriate rate. CONCLUSIONS: The observed benchmark rate converged on the evidence-based estimate of the appropriate rate of use of RT for lung cancer, suggesting that either measure might reasonably be used as a "standard" against which to compare rates observed in similar populations elsewhere.

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