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Biomedical subjects

W J Mackillop

Publications and source records attributed to W J Mackillop.

At least 37 records · Page 2Linked to original sources
PubMed2001

Glottic cancer in Ontario, Canada and the SEER areas of the United States. Do different management philosophies produce different outcome profiles?

We compared the management and outcome of glottic cancer in Ontario, Canada to that in the Surveillance, Epidemiology and End Results (SEER) Program areas in the United States to determine whether the greater use of primary radiotherapy with surgery reserved for salvage in Ontario was associated with similar survival and better larynx retention rates than the U.S. approach where primary surgery is used more often. Electronic, clinical and hospital data were linked to cancer registry data and supplemented by chart review where necessary. Initial treatment and survival in patients diagnosed in the SEER areas from 1988 through 1994 were compared to patients from Ontario diagnosed from 1982 through 1995. Actuarial laryngectomy rates were compared for patients over 65 at diagnosis in the two regions. Analyses were conducted over all cases and stratified by disease stage. In localized disease (T1 or T2), conservative treatment was the most common initial treatment in both regions, although total laryngectomy was used more often in SEER than Ontario (6.2% vs. 0.2%, respectively, P <.001). In advanced disease (T3 or T4), total laryngectomy was more commonly used as initial treatment in SEER (62.9% vs. 21.0% in Ontario, P < or =.001). Over all cases, the relative survival rate was 80% in Ontario at 5 years compared to 78% in SEER (P =.33). In localized disease, the relative survival rates were 4 to 5% higher in Ontario from the second year on, while in advanced disease 2 to 3% higher rates in SEER did not approach statistical significance. Actuarial laryngectomy rates at 3 years differed between the two regions, with a 4% higher rate in SEER (P =.01). In localized disease, 12.6% of Ontario patients had a laryngectomy by 3 years postdiagnosis compared to 17.9% in SEER (P =.05). In advanced disease, the rates were 63.3% and 79.2%, respectively (P =.07). There are large differences in the management of glottic cancer between the SEER areas of the U.S. and Ontario and no evidence that a policy emphasizing radiotherapy with surgery reserved for salvage is associated with worse survival. Ultimate laryngectomy rates are lower in Ontario for localized disease and may be lower for advanced disease. Conservation treatment should be used for localized disease while the treatment decision in advanced disease may be especially sensitive to patient values for voice retention versus initial cure.

Aged↗
PubMed2000

Involved-field radiotherapy alone for early-stage non-small-cell lung cancer.

PURPOSE: To describe the outcome of involved-field radiotherapy in patients with early-stage non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: A written policy for the radical treatment of early-stage NSCLC with involved-field radiotherapy was adopted at our center in 1986. The sites of known disease were treated to a dose of 52.5 Gy in 20 daily fractions over 4 weeks without elective irradiation of radiologically uninvolved regional nodes. We have reviewed the outcome of this policy in 102 patients treated with radiotherapy alone between 1986 and 1995. RESULTS: The patients' median age was 71.5 years. The stage distribution was as follows: T1, 33.3%; T2, 56.9%; T3, 8.8%; and T4, 1.0%. Only 5 cases were N1; the remainder were N0. Most patients (76.5%) were not surgical candidates because of co-morbidity. Ninety-three percent had a CT of the thorax as part of their initial staging, while mediastinoscopy was performed in only 16.7%. Overall survival was 35% at 3 years and 16% at 5 years. Recurrence free survival was 23.9% at 3 years and 13. 9% at 5 years. Cause-specific survival was 43.5% at 3 years and 26. 8% at 5 years. Of those who recurred, 68.9% had a local component of failure at initial relapse, and 49.2% failed locally without evidence of regional or distant metastases. Isolated regional nodal relapse at initial failure occurred in only 6.6% of recurrences. There were no treatment interruptions due to acute toxicity and no treatment-related deaths. CONCLUSION: Involved-field radiotherapy alone cures a small but significant number of patients with early-stage NSCLC. This approach is recommended in patients who are unfit for surgery and who have severely compromised pulmonary function that would preclude the use of wide-field radiotherapy. The dose used in this study was well tolerated, but produced suboptimal local control rates.

Aged↗
PubMed2000

Associations between community income and cancer incidence in Canada and the United States.

BACKGROUND: Associations between socioeconomic status (SES) and the incidence of cancer have been reported previously in the U.S. Canada has more comprehensive health care and social programs than the U.S. The purpose of this study was to compare the strength of associations between SES and cancer incidence in Canada and the U.S. METHODS: The regions studied were the Canadian province of Ontario and the areas of the U.S. covered by the Surveillance, Epidemiology, and End Results (SEER) program. The populations at risk were defined using the 1991 Canadian Census and the 1990 U.S. Census. The populations of Ontario and of the SEER areas of the U.S. were each divided into deciles on the basis of median household income. Population-based cancer registries were used to identify incident cases. Age-standardized incidence rates for all major groups of malignant diseases were calculated for each SES decile in Ontario and in the U.S. Income-associated incidence gradients observed in Ontario and the U.S. were compared. RESULTS: The incidence of most types of cancer was similar in Ontario and the U.S. In both countries, there were moderately strong, inverse associations between income level and the incidence of carcinomas of the cervix, the head and neck region, the lung, and the gastrointestinal tract. In both Ontario and the U.S., several of these diseases were twice as common in the bottom income decile than they were in the top decile. In contrast, carcinoma of the female breast and carcinoma of the prostate were more common among higher income communities in both countries, but the observed associations were weaker in Ontario. CONCLUSIONS: Despite Canada's universal health insurance and more comprehensive social security system, the association between lower socioeconomic status and the incidence of many common cancers is just as strong in Ontario as it is in the U.S. The mechanisms responsible for these associations require further investigation.

Age Factors↗
PubMed2000

The management and outcome of bladder carcinoma in Ontario, 1982-1994.

BACKGROUND: To the authors' knowledge no previous study has described the management and outcome of bladder carcinoma on a population-based level. The objective of the current study was to describe the characteristics, treatment, and outcome of newly diagnosed invasive bladder carcinoma (n = 20,822) reported in Ontario, Canada between 1982-1994. METHODS: Electronic records of invasive bladder carcinoma (International Classification of Diseases code 188) from the Ontario Cancer Registry were linked to surgical and radiotherapy (RT) records. Bivariate and multivariate techniques were used to assess variations in the use of initial cystectomy and pelvic RT. The authors modeled the likelihood of death after diagnosis and the probability of cystectomy free survival. All analyses were controlled for age, gender, histology, and year of diagnosis. RESULTS: The most common histologic type was papillary transitional cell carcinoma. Maximum initial treatment was comprised of total cystectomy (5.1%), partial cystectomy or open excision (3. 5%), pelvic RT (5.9%), transurethral resection of the bladder (66. 7%), or lesser or no procedures (18.7%). The use of total cystectomy and pelvic RT varied among the regions of Ontario. Overall 5-year survival was 58.8%, and was 86.5% for patients with papillary histology. In multivariate analysis, although survival was similar among the regions, the relative risk of cystectomy conditional on survival varied. CONCLUSIONS: Papillary tumors portend a better survival than nonpapillary tumors. Variations in the use of total cystectomy and in the use of pelvic RT among the regions of Ontario did not appear to be associated with variations in survival. However, cystectomy free survival appeared to vary among the regions. These results suggest that patients can be managed safely using a bladder-preserving approach.

Adult↗
PubMed2000

Association between age and the utilization of radiotherapy in Ontario.

PURPOSE: The purpose of this study was to assess whether: (i) radiotherapy (RT) utilization varies with age in Ontario cancer patients; (ii) age-associated differences in the use of RT (if they exist) vary with cancer site and treatment intent; (iii) the age-associated variation in RT utilization is comparable to the decline in functional status in the general population; and (iv) the variation with age is due to differences in referral to a cancer center or to subsequent decisions. METHODS AND MATERIALS: Details for several cancer sites diagnosed between 1984-1994 were obtained from the Ontario Cancer Registry (OCR). RT records from all treatment centers were linked to the OCR database. Information about the functional status of the Canadian population was obtained from the 1994 National Population Health Survey conducted by Statistics Canada. RESULTS: The rate of RT use declined with age, particularly for adjuvant and palliative indications. The relative decline in RT with age exceeded the relative decline in functional status with age in the general population. Most of the decline in RT use was related to a decline in referral to cancer centers. CONCLUSIONS: The referral for, and use of, palliative and adjuvant RT decreases more with age than can be explained by age-associated decline in functional status observed in the general population.

Age Distribution↗
PubMed2000

Cancers of the upper aerodigestive tract in Ontario, Canada, and the United States.

BACKGROUND: Squamous cancers of the upper aerodigestive tract (UADT) are related to the use of tobacco and/or alcohol, and in North America they are more common among the poor. They are usually locoregionally confined at diagnosis, and local treatment with surgery and/or radiation therapy is often curative. This study compares the incidence and survival of this group of diseases in Canada and the U.S., two North American neighbors with many cultural similarities but significant differences in their health care and social programs. METHODS: To describe and compare the case mix, incidence, and outcome of squamous cancers of the UADT in Ontario, Canada, and the U.S., we used the Ontario Cancer Registry (OCR) and the Surveillance, Epidemiology, and End Results (SEER) registries in the U.S. to identify all cases of cancer with International Classification of Disease (ICD) codes 141, 143-9, 160-1, and a subset of 140, which were diagnosed between 1982 and 1994. ICD-O histology codes were placed into clinically relevant groupings, and ICD-9 site codes were grouped into sites as defined by the International Union Against Cancer and the American Joint Committee on Cancer. Age-adjusted incidence rates were calculated for each site. For the SEER registry, race specific incidence rates were also calculated. Observed and expected survival were plotted by site and registry, and from these, relative survival was calculated. Survival was compared during the first 5 years after diagnosis and during the next 5 years among patients who had survived the first 5 years. RESULTS: Of the 16,577 and 42,990 cases identified in the OCR and SEER registries, respectively, squamous cancer was by far the most common histology (94.1% in OCR, 94.6% in SEER) and will form the main subject of this report. The distribution of squamous cancers by site, subsite, age, and gender were remarkably similar in the two populations. Overall, the incidence was about 17% higher in the U.S. than in Ontario, and this difference was seen for all sites except the nasopharynx, which was more common in Ontario. The higher incidence in the U.S. in part reflects the much higher rate for African Americans than for Americans of other ethnic backgrounds. During the first 5 years after diagnosis, when most deaths from UADT cancer occur, there was a significant relative survival difference in favor of the U.S. for cancer of the supraglottis, and in favor of Ontario for cancer of the oral cavity. There was a nonsignificant trend in favor of Ontario for cancer of the nasopharynx. Within the SEER population, for all sites except the nasopharynx, 5-year relative survival was considerably worse for African Americans than for Americans of other ethnic backgrounds. Examination of survival beyond 5 years after diagnosis for patients who had survived the first 5 years revealed that for all sites, the observed survival continued to diverge markedly from the expected survival. The excess mortality ranged from less than 20% for glottic and nasopharyngeal cancers to about 30-40% for oropharyngeal and supraglottic cancers. CONCLUSIONS: Despite remarkable similarities in case mix between the two countries, UADT cancers were more frequent in the SEER population of the U.S. than in Ontario, and this was partly attributable to the much higher incidence among African Americans. Significant differences between the registries in 5-year survival were seen for several sites. African Americans with UADT cancers had much worse prognoses than did Americans of other ethnic backgrounds. Patients who survive their UADT cancer remain at a higher-than-expected risk of death even after they have been cured.

Disease-Free Survival↗
PubMed2000

A population-based study of the effectiveness of breast conservation for newly diagnosed breast cancer.

PURPOSE: Our objective was to evaluate the effectiveness of breast conservation for newly diagnosed breast cancer. Effectiveness was operationalized as two outcomes within 5 years of the diagnosis of breast cancer: the probability of mastectomy-free survival (either death or mastectomy count as event, whichever comes first), and the probability of mastectomy conditional on survival (mastectomy counts as event, observations censored at death). METHODS AND MATERIALS: We linked records of 46,687 new cases of breast cancer from 1982 to 1991 in the Ontario Cancer Registry to records of surgery from 1982 to 1995, radiotherapy (RT) from 1982 to 1992, and median household income from the 1986 census. We labeled breast surgery within 4 months and postoperative RT within 12 months of diagnosis as treatment for newly diagnosed breast cancer. Surgery was categorized as mastectomy, lumpectomy plus RT, lumpectomy alone, or no surgical procedure. Among cases that did not undergo mastectomy within 4 months of diagnosis, we labeled mastectomy subsequent to 4 months after diagnosis as treatment failure. We performed life-table analysis and Cox proportional hazards regression, to describe the probability of mastectomy conditional on survival and the probability of mastectomy-free survival. RESULTS: A total of 16,279 cases underwent lumpectomy as the maximum procedure on the breast within 4 months of diagnosis, and 49.7% of these received postoperative RT. Compared to the provincial mean, regions with higher rates of lumpectomy plus RT have higher probability of mastectomy-free survival and lower probability of mastectomy conditional upon survival 5 years after diagnosis of breast cancer. CONCLUSIONS: These findings are consistent with a hypothesis that breast conservation is effective in the overall breast cancer population of Ontario within the first 5 years after diagnosis.

Adult↗
PubMed2000

Management and outcome of glottic cancer: a population-based comparison between Ontario, Canada and the SEER areas of the United States. Surveillance, Epidemiology and End Results.

OBJECTIVE: We compared treatment practice and outcome in glottic cancer in Ontario, Canada to that in the Surveillance, Epidemiology and End Results (SEER) program areas in the United States to determine whether the Ontario emphasis on the use of delayed combined therapy was associated with similar survival and better laryngectomy-free survival than the U.S. approach, which emphasizes greater use of surgery. METHODS: Electronic, clinical, and hospital data were linked to cancer registry data. The study groups compared on survival comprised all patients diagnosed from 1982 to the end of 1991 in Ontario (2324 patients) and in the SEER areas (5715 patients). Comparisons on initial treatment, laryngectomy rates, and laryngectomy-free survival were limited to subsets of these study populations due to data availability. Initial treatment data were provided by the SEER registries in the U.S. and by the cancer clinic and hospitalization data in Ontario. Information about laryngectomies performed subsequent to initial treatment was available from Medicare hospitalization data in the U.S. and from Canadian Institute for Health Information hospitalization data in Ontario. RESULTS: Although radiotherapy was the most common initial treatment in both areas, it was used more often in Ontario (84.4% versus 63.2% in the U.S. [p < 0.001]). Relative survival was not statistically different with a relative risk comparing SEER to Ontario of 1.09, 95% confidence interval (CI) (0.93, 1.29). Laryngectomy rates were similar with a relative risk of 1.01, 95% CI (0.67, 1.52), and it follows from the survival and laryngectomy rate comparisons that the laryngectomy-free survival was not statistically different (p = .95). CONCLUSIONS: There are large differences in the management of glottic cancer between the U.S. and Ontario and no corresponding differences in survival or laryngectomy-free survival. This work highlights a need for more clinical investigation into the relative merits of differing management policies in glottic cancer.

Aged↗
PubMed1999

A population-based study of the use and outcome of radical radiotherapy for invasive bladder cancer.

PURPOSE: The objective of this study is to describe the use and outcome of radical radiotherapy for bladder cancer in the province of Ontario, Canada, between 1982 and 1994. METHODS: Electronic records of invasive bladder cancer (ICD code 188) from the Ontario Cancer Registry were linked to surgical records from all Ontario hospitals and radiotherapy (RT) records from all Ontario cancer centers. We identified cases receiving radical RT by selecting RT records containing "bladder" or "pelvis" anatomic region codes and a radical or curative intent code (or dose >39.5 Gy if intent missing). We identified cases receiving salvage total cystectomy by selecting total cystectomy procedure codes occurring at any time beyond 4 months from the start of radical RT. We used life table methods to compute the following: the time from diagnosis to radical RT, the time from radical RT to salvage cystectomy, overall and cause-specific survival from radical radiotherapy to death, and overall and cause-specific survival from salvage cystectomy to death. We modeled the factors associated with time to death, time to cystectomy conditional on survival, and time to cystectomy or death, whichever came first, using Cox proportional hazards regression. RESULTS: From the 20,906 new cases of bladder cancer diagnosed in Ontario from 1982 to 1994, we identified 1,372 cases treated by radical radiotherapy (78% male, 22% female; mean age 69.8 years). The median interval to start of radical RT from diagnosis was 13.4 weeks. Ninety-three percent of patients were treated on high-energy linacs, and the most common dose/fractionation scheme was 60 Gy/30 (31% of cases). Five-year survival rates were as follows: bladder cancer cause-specific, 41%; overall, 28%; cystectomy-free, 25%; bladder cancer cause-specific following salvage cystectomy, 36%; overall following salvage cystectomy, 28%. Factors associated with a higher risk of death and a poorer cystectomy-free survival were histology (squamous or nonpapillary transitional cell carcinoma [TCC]) and advanced age. CONCLUSION: This population-based study confirms previous institutional studies and clinical trials and shows that radical RT has a curative role in the management of invasive bladder cancer and allows about one-quarter of patients receiving radiotherapy to survive 5 years while retaining the bladder. Salvage cystectomy following RT provides a chance of cure at the time of bladder relapse.

Adolescent↗
PubMed1999

A population-based study of rectal cancer: permanent colostomy as an outcome.

PURPOSE: The objectives of this study are to describe the utilization of surgery and of radiotherapy in the treatment of newly diagnosed rectal cancer in Ontario between 1982 and 1994, and to describe the probability of permanent colostomy at any time after the diagnosis of rectal cancer, as an outcome of the treatment of newly diagnosed rectal cancer. METHODS AND MATERIALS: Electronic records of rectal cancer (International Classification of Diseases code 154) from the Ontario Cancer Registry (n = 18,695, excluding squamous, basaloid, cloacogenic, and carcinoid histology) were linked to surgical records from all Ontario hospitals, and radiotherapy (RT) records from Ontario cancer centers. Procedures occurring within 4 months of diagnosis, or within 4 months of another procedure for rectal cancer, were considered part of initial treatment. Multivariate analyses controlled for age, sex, and year of diagnosis. RESULTS: Resection plus permanent colostomy was performed in 33.1% of cases, whereas local excision or resection without permanent colostomy was performed in 38.2%. Multivariate logistic regression demonstrated higher odds ratios (OR) for resection plus permanent colostomy in all regions of Ontario relative to Toronto. The OR for postoperative RT following local excision or resection without permanent colostomy varied among the regions relative to Toronto (e.g., OR Ottawa = 0.59, OR Hamilton = 0.76, OR London = 1.25). The relative risk (RR) of colostomy conditional upon survival within 5 years from diagnosis varied among regions relative to Toronto (e.g., RR Ottawa = 1.21, RR Hamilton = 1.20). CONCLUSIONS: There is regional variation in the utilization of resection with permanent colostomy, and in the utilization of postoperative RT among cases not undergoing permanent colostomy. Regions with higher initial rates of resection plus permanent colostomy continue to experience higher probability of permanent colostomy 5 years after diagnosis of rectal cancer. Higher initial rates of permanent colostomy may be malleable to interventions aimed at improving overall outcomes.

Age Factors↗
PubMed1999

Changes in the use of radiotherapy in Ontario 1984-1995.

PURPOSE: To describe changes in the use of radiotherapy in the management of cancer in Ontario between January 1, 1984 and December 31, 1995. METHODS: A retrospective review of prospectively gathered electronic records of all radiotherapy for cancer at nine provincial cancer treatment centres. RESULTS: Over the 12 years of the study, the incidence of cancer increased by 33%. The number of curative and adjuvant courses per incident case increased by 39.3% and the number of palliative courses per incident case decreased by 15.8%. The mean number of fractions per curative and adjuvant course increased by 13%, and the mean number of fractions per palliative course decreased by 22%. The number of curative fractions per incident case increased by 63%, and the number of palliative fractions per incident case decreased by 32%. The increase in curative workload was mainly due to an increase in the incidence of prostate cancer, to an increase in the number of courses per incident case in breast and prostate cancer, and to an increase in the number of fractions per curative course in every disease group. The decrease in palliative workload was due to a decrease in the number of courses per incident case in most disease groups, and to a decrease in the number of fractions per course in most disease groups. CONCLUSIONS: In Ontario, between 1984 and 1995, there was a large shift in workload from palliative radiotherapy to curative radiotherapy. Potential causes for this phenomenon are discussed.

Brachytherapy↗
PubMed1999

Mortality from myocardial infarction following postlumpectomy radiotherapy for breast cancer: a population-based study in Ontario, Canada.

PURPOSE: To compare the risk of mortality from myocardial infarction (MI) after left-sided postlumpectomy radiotherapy (RT) to the risk after right-sided postlumpectomy RT. METHODS: We conducted a population-based cohort study of cases of invasive female breast cancer in Ontario, diagnosed between January 1, 1982 and December 31, 1987 (n = 25,570). Records of the Ontario Cancer Registry (OCR) were linked to hospital procedure and discharge abstracts and to RT records from Ontario cancer centers. A case was labelled as lumpectomy if this was the maximum breast surgery within 4 months of diagnosis. Postlumpectomy RT occurred up to 1 year postdiagnosis. Laterality was assigned from the laterality descriptor of the RT records. A case was labelled as having had a fatal MI if ICD code 410 (myocardial infarction) was recorded as the cause of death in the OCR. We used logistic regression to compare the likelihood of utilization of: 1. Dose per fraction > 2.00 Gy; 2. cobalt vs. linac; and 3. boost RT. We used life table analysis and the log rank test comparing the time to fatal MI from diagnosis of breast cancer between women who received left-sided postlumpectomy RT and women who received right-sided. We used Cox proportional hazards models to study the relative risk for left-sided cases overall, and stratified by age, RT characteristics, and among conditional survival cohorts. RESULTS: Postlumpectomy RT was received by 1,555 left-sided and 1,451 right-sided cases. With follow-up to December 31, 1995, 2% of women with left-sided RT had a fatal MI compared to 1% of women with right-sided RT. Comparison of the time to failure between women who had left-sided RT and women who had right-sided RT showed the left-sided RT group to be associated with a higher risk of fatal MI (p = 0.02). Adjusting for age at diagnosis, the relative risk for fatal MI with left-sided postlumpectomy RT was 2.10 (1.11, 3.95). CONCLUSION: Among women who received postlumpectomy RT for breast cancer in Ontario between 1982-1987, left-sided postlumpectomy RT was associated with a higher risk of fatal MI compared to right-sided.

Adult↗
PubMed1999

A real-time audit of radiation therapy in a regional cancer center.

PURPOSE: To report the development, structure, and implementation of a real-time clinical radiotherapy audit of the practice of radiation oncology in a regional cancer center. METHODS AND MATERIALS: Radiotherapy treatment plans were audited by a real-time peer-review process over an 8-year period (1989-1996). The overall goal of the audit was to establish a process for quality assurance (QA) of radiotherapy planning and prescription for individual patients. A parallel process was developed to audit the implementation of intervention-specific radiotherapy treatment policies. RESULTS: A total of 3052 treatment plans were audited. Of these, 124 (4.1%) were not approved by the audit due to apparent errors in radiation planning. The majority of the nonapproved plans (79%) were modified prior to initiating treatment; the audit provided important clinical feedback about individual patient care in these instances. Most of the remaining nonapproved plans were deviations from normal practice due to patient-specific considerations. A further 110 (3.6% of all audited plans) were not approved by the audit due to deviations from radiotherapy treatment policy. A minority of these plans (22%) were modified prior to initiating treatment and the remainder provided important feedback for continuous quality improvement of treatment policies. CONCLUSION: A real-time audit of radiotherapy practice in a regional cancer center setting proved feasible and provided important direct and indirect patient benefits.

Canada↗
PubMed1999

Associations between community income and cancer survival in Ontario, Canada, and the United States.

PURPOSE: The objectives of this study were as follows: (1) to compare the magnitude of the association between socioeconomic status (SES) and cancer survival in the Canadian province of Ontario with that in the United States (U.S.), and (2) to compare cancer survival in communities with similar SES in Ontario and in the U.S. METHODS: The Ontario Cancer Registry provided information about all cases of invasive cancer diagnosed in Ontario from 1987 to 1992, and the Surveillance, Epidemiology and End Results Registry (SEER) provided information about all cases diagnosed in the SEER regions of the U.S. during the same time period. Census data provided information about SES at the community level. The product-limit method was used to describe cause-specific survival. Cox proportional hazards models were used to describe the association between SES and the risk of death from cancer. RESULTS: There were significant associations between SES and survival for most cancer sites in both the U.S. and Ontario, but the magnitude of the association was usually larger in the U.S. In the poorest communities, there were significant survival advantages in favor of cancer patients in Ontario for many disease groups, including cancers of the lung, head and neck region, cervix, and uterus. However, in upper- and middle-income communities, there were significant survival advantages in favor of the U.S. for all cases combined and for several individual diseases, including cancers of the breast, colon and rectum, prostate, and bladder. CONCLUSION: The association between SES and cancer survival is weaker in Ontario than it is in the U.S. This is due to a combination of better survival among patients in the poorest communities and worse survival among patients in the wealthier communities of Ontario relative to those in the U.S.

Adult↗
PubMed1998

What prostate cancer patients should know: variation in professionals' opinions.

PURPOSE: This study was designed to determine what questions health-care professionals think should be addressed with curable prostate cancer patients before treatment decisions are made. METHOD: A survey was distributed to radiation oncologists, urologists, medical oncologists, nurses and radiation therapy technologists (RTTs) involved in treating prostate cancer patients. Participants were asked to judge the importance of addressing each of 78 questions (essential/important/no opinion/avoid) with a described hypothetical patient prior to the treatment decision. Eighty participants were later selected at random for a retest. RESULTS: The overall response rate was 55% (284/518) on the initial survey and 56% (45/80) on the retest. The relative importance of the various questions was similar across groups (r(76) ranged from 0.75 to 0.91, all P<0.001). Despite the between-group similarity, opinions within each group varied widely. For example, among oncologists, the number of questions deemed essential by individual respondents ranged from five to 69, with >90% respondent agreement on only 15 of the 78 questions. The extent of agreement was similar in the other groups. The retest showed that essential and important responses were reasonably stable, i.e. 92% of questions judged essential at one time were judged either essential (58%) or important (34%) at the other time. CONCLUSIONS: Although the relative importance of addressing the various questions appears similar across the professional groups involved in the care of prostate patients, within each profession there seems to be little agreement. The lack of agreement includes both how many questions are essential to address and whether or not most individual questions are essential.

Decision Making↗
PubMed1998

Mortality from myocardial infarction after adjuvant radiotherapy for breast cancer in the surveillance, epidemiology, and end-results cancer registries.

PURPOSE: To compare the risk for fatal myocardial infarction (MI) after adjuvant radiotherapy (RT) for left-sided breast cancer with the risk for MI after adjuvant RT for right-sided breast cancer. METHODS: We studied women with local- and regional-stage breast cancer diagnosed from 1973 to 1992 from the Surveillance, Epidemiology, and End-Results (SEER) cancer registries. We performed life-table analysis, the log-rank test, and Cox proportional hazards regression to compare the time to fatal MI from diagnosis between left-sided and right-sided cases, censoring deaths from other causes. RESULTS: Among irradiated patients, the relative risk (RR) for fatal MI in women with left-sided breast cancer was 1.17 (95% confidence interval [CI], 1.01 to 1.36), controlling for age, compared with those with right-sided breast cancer. The RR for fatal MI among left-sided cases was increased for those under the age of 60 years (RR = 1.98; 95% CI, 1.31 to 2.97) compared with right-sided cases, but not at age 60 years or older. Among women with irradiated regional-stage cancer who were younger than 60 years of age, the risk was significantly increased (RR = 2.24; 95% CI, 1.38 to 3.64) for those with left-sided compared with right-sided breast cancer, but not among patients aged 60 years or older. Among irradiated local-stage cases, the risk for those with left-sided breast cancer was not significantly elevated in either age category. Analysis of 5-year conditional survival cohorts showed an increased risk for irradiated left-sided cases among women younger than 60 years of age in the 10- to 15-year conditional survival cohort (RR = 5.28; 95% CI, 1.82 to 15.3). CONCLUSION: Adjuvant RT for left-sided breast cancer diagnosed in women younger than 60 years of age is associated with a higher risk for fatal MI 10 to 15 years later compared with adjuvant RT for right-sided cases.

Adult↗
PubMed1998

Cancer staging.

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Academies and Institutes↗