Breast cancer diagnosis and treatment wait times in specialized diagnostic units compared with usual care: a population-based study.

Background: Breast assessment sites (bass) were developed to provide expedited and coordinated care for patients being evaluated for breast cancer (bca) in Ontario. We compared the diagnostic and treatment intervals for patients diagnosed at a bas and for those diagnosed through a usual care (uc) route. Methods: This population-based, cross-sectional study of patients diagnosed with bca in Ontario during 2007-2015 used linked administrative data. "Diagnostic interval" was the time from the earliest cancer-related health care encounter before diagnosis to diagnosis; "treatment interval" was the time from diagnosis to treatment. Diagnosis at a bas was determined from the patient's biopsy and mammography institutions. Interval lengths for the bas and uc groups were compared using multivariable quantile regression, stratified by detection method. Results: The diagnostic interval was shorter for patients who were bas-diagnosed than for those who were uc-diagnosed, with adjusted median differences of -4.0 days [95% confidence interval (ci): -3.2 days to -4.9 days] for symptomatic patients and -5.4 days (95% ci: -4.7 days to -6.1 days) for screen-detected patients. That association was modified by stage at diagnosis, with larger differences in patients with early-stage cancers. In contrast, the treatment interval was longer in patients who were bas-diagnosed than in those who were uc-diagnosed, with adjusted median differences of 4.2 days (95% ci: 3.8 days to 4.7 days) for symptomatic patients and 4.2 days (95% ci: 3.7 days to 4.8 days) for screen-detected patients. Conclusions: Diagnosis of bca through a bas was associated with a shorter diagnostic interval, but a longer treatment interval. Although efficiencies in the diagnostic interval might help to reduce distress experienced by patients, the longer treatment intervals for patients who are bas-diagnosed remain a cause for concern.

Disparities in breast cancer diagnosis for immigrant women in Ontario and BC: results from the CanIMPACT study.

BACKGROUND: In Canada, clinical practice guidelines recommend breast cancer screening, but there are gaps in adherence to recommendations for screening, particularly among certain hard-to-reach populations, that may differ by province. We compared stage of diagnosis, proportion of screen-detected breast cancers, and length of diagnostic interval for immigrant women versus long-term residents of BC and Ontario. METHODS: We conducted a retrospective cohort study using linked administrative databases in BC and Ontario. We identified all women residing in either province who were diagnosed with incident invasive breast cancer between 2007 and 2011, and determined who was foreign-born using the Immigration Refugee and Citizenship Canada database. We used descriptive statistics and bivariate analyses to describe the sample and study outcomes. We conducted multivariate analyses (modified Poisson regression and quantile regression) to control for potential confounders. RESULTS: There were 14,198 BC women and 46,952 Ontario women included in the study population, of which 11.8 and 11.7% were foreign-born respectively. In both provinces, immigrants and long-term residents had similar primary care access. In both provinces, immigrant women were significantly less likely to have a screen-detected breast cancer (adjusted relative risk 0.88 [0.79-0.96] in BC, 0.88 [0.84-0.93] in Ontario) and had a significantly longer median diagnostic interval (2 [0.2-3.8] days in BC, 5.5 [4.4-6.6] days in Ontario) than long-term residents. Women from East Asia and the Pacific were less likely to have a screen-detected cancer and had a longer diagnostic interval, but were diagnosed at an earlier stage than long-term residents. In Ontario, women from Latin America and the Caribbean and from South Asia were less likely to have a screen-detected cancer, had a longer median diagnostic interval, and were diagnosed at a later stage than long-term residents. These findings were not explained by access to primary care. CONCLUSIONS: There are inequalities in breast cancer diagnosis for Canadian immigrant women. We have identified particular immigrant groups (women from Latin America and the Caribbean and from South Asia) that appear to be subject to disparities in the diagnostic process that need to be addressed in order to effectively reduce gaps in care.

Symptom appraisal, help seeking, and lay consultancy for symptoms of head and neck cancer.

OBJECTIVE: Early diagnosis is important in head and neck cancer (HNC) patients to maximize the effectiveness of the treatments and minimize the debilitation associated with both the cancer and the invasive treatments of advanced disease. Many patients present with advanced disease, and there is little understanding as to why. This study investigated patients' symptom appraisal, help seeking, and lay consultancy up to the time they first went to see a health care professional (HCP). METHODS: We interviewed 83 patients diagnosed with HNC. The study design was cross sectional and consisted of structured telephone interviews and a medical chart review. We gathered information on the participant's personal reactions to their symptoms, characteristics of their social network, and the feedback they received. RESULTS: We found that 18% of the participants thought that their symptoms were urgent enough to warrant further investigation. Participants rarely (6%) attributed their symptoms to cancer. Eighty-nine percent reported that they were unaware of the early warning signs and symptoms of HNC. Fifty-seven percent of the participants disclosed their symptoms to at least one lay consultant before seeking help from an HCP. The lay consultants were usually their spouse (77%), and the most common advice they offered was to see a doctor (76%). Lastly, 81% of the participants report that their spouse influenced their decision to see an HCP. CONCLUSIONS: The results of this study suggest that patients frequently believe that their symptoms were nonurgent and that their lay consultants influence their decision to seek help from an HCP.

Measuring the Quality of Personal Care in Patients Undergoing Radiotherapy for Prostate Cancer.

AIMS: To describe the quality of the non-technical component of the care (personal care) of patients receiving radical radiotherapy for prostate cancer and to identify elements of personal care that should be priorities for quality improvement. MATERIALS AND METHODS: One hundred and eight patients undergoing radiotherapy for localised prostate cancer completed a self-administered questionnaire that asked them to rate the importance of 143 non-technical elements of care and to rate the quality of their own care with respect to each element. The elements that a patient rated as both 'very important' and less than 'very good' were deemed to be his priorities for improvement. The priorities of the population were established by ranking the elements based on the percentage of patients who identified them as a priority (importance/quality analysis). RESULTS: The response rate was 65%. The percentage of elements rated 'very good' varied from patient to patient: median 79% (interquartile range 69-92%). The percentage of elements rated either 'very good' or 'good' was higher: median 96% (interquartile range 86-98%). Nonetheless, almost every patient rated at least some elements of his care as less than optimal, regardless of the cut-off point used to define optimal quality. Patients assigned their lowest quality ratings to elements relating to the quality of the treatment environment and comprehensiveness of additional services available to them. However, patients rated most of these elements as relatively unimportant, and importance/quality analysis identified elements of care relating to communication of information about the disease and its treatment as the highest priorities for quality improvement. CONCLUSIONS: Most patients rated most elements of their personal care as very good, but almost all were able to identify some elements that were less than optimal. When ratings of quality were integrated with ratings of importance, elements relating to communication emerged as the patients' highest priorities for quality improvement.

Use of physician services during the survivorship phase: a multi-province study of women diagnosed with breast cancer.

INTRODUCTION: Oncologists have traditionally been responsible for providing routine follow-up care for cancer survivors; in recent years, however, primary care providers (pcps) are taking a greater role in care during the follow-up period. In the present study, we used a longitudinal multi-province retrospective cohort study to examine how primary care and specialist care intersect in the delivery of breast cancer follow-up care. METHODS: Various databases (registry, clinical, and administrative) were linked in each of four provinces: British Columbia, Manitoba, Ontario, and Nova Scotia. Population-based cohorts of breast cancer survivors were identified in each province. Physician visits were identified using billings or claims data and were classified as visits to primary care (total, breast cancer-specific, and other), oncology (medical oncology, radiation oncology, and surgery), and other specialties. The mean numbers of visits by physician type and specialty, or by combinations thereof, were examined. The mean numbers of visits for each follow-up year were also examined by physician type. RESULTS: The results showed that many women (>64%) in each province received care from both primary care and oncology providers during the follow-up period. The mean number of breast cancer-specific visits to primary care and visits to oncology declined with each follow-up year. Interprovincial variations were observed, with greater surgeon follow-up in Nova Scotia and greater primary care follow-up in British Columbia. Provincial differences could reflect variations in policies and recommendations, relevant initiatives, and resources or infrastructure to support pcp-led follow-up care. CONCLUSIONS: Optimizing the role of pcps in breast cancer follow-up care might require strategies to change attitudes about pcp-led follow-up and to better support pcps in providing survivorship care.

Multigene expression profile testing in breast cancer: is there a role for family physicians?

BACKGROUND: Family physicians (fps) play a role in aspects of personalized medicine in cancer, including assessment of increased risk because of family history. Little is known about the potential role of fps in supporting cancer patients who undergo tumour gene expression profile (gep) testing. METHODS: We conducted a mixed-methods study with qualitative and quantitative components. Qualitative data from focus groups and interviews with fps and cancer specialists about the role of fps in breast cancer gep testing were obtained during studies conducted within the pan-Canadian canimpact research program. We determined the number of visits by breast cancer patients to a fp between the first medical oncology visit and the start of chemotherapy, a period when patients might be considering results of gep testing. RESULTS: The fps and cancer specialists felt that ordering gep tests and explaining the results was the role of the oncologist. A new fp role was identified relating to the fp-patient relationship: supporting patients in making adjuvant therapy decisions informed by gep tests by considering the patient's comorbid conditions, social situation, and preferences. Lack of fp knowledge and resources, and challenges in fp-oncologist communication were seen as significant barriers to that role. Between 28% and 38% of patients visited a fp between the first oncology visit and the start of chemotherapy. CONCLUSIONS: Our findings suggest an emerging role for fps in supporting patients who are making adjuvant treatment decisions after receiving the results of gep testing. For success in this new role, education and point-of-care tools, together with more effective communication strategies between fps and oncologists, are needed.

Effect of specialized diagnostic assessment units on the time to diagnosis in screen-detected breast cancer patients.

BACKGROUND: The duration of the cancer diagnostic process has considerable influence on patients' psychosocial well-being. Breast diagnostic assessment units (DAUs) in Ontario, Canada are designed to improve the quality and timeliness of care during a breast cancer diagnosis. We compared the diagnostic duration of patients diagnosed through a DAU vs usual care (UC). METHODS: Retrospective population-based cohort study of 2499 screen-detected breast cancers (2011) using administrative health-care databases linked to the Ontario Cancer Registry. The diagnostic interval was measured from the initial screen to cancer diagnosis. Diagnostic assessment unit use was based on the biopsy and/or surgery hospital. We compared the length of the diagnostic interval between the DAU groups using multivariable quantile regression. RESULTS: Diagnostic assessment units had a higher proportion of patients diagnosed within the 7-week target compared with UC (79.1% vs 70.2%, P<0.001). The median time to diagnosis at DAUs was 26 days, which was 9 days shorter compared with UC (95% CI: 6.4-11.6). This effect was reduced to 8.3 days after adjusting for all study covariates. Adjusted DAU differences were similar at the 75th and 90th percentiles of the diagnostic interval distribution. CONCLUSIONS: Diagnosis through an Ontario DAU was associated with a reduced time to diagnosis for screen-detected breast cancer patients, which likely reduces the anxiety and distress associated with waiting for a diagnosis.

Adherence to and uptake of clinical practice guidelines: lessons learned from a clinical practice guideline on chemotherapy concomitant with radiotherapy in head-and-neck cancer.

BACKGROUND: Clinical practice guidelines (cpgs) are systematically developed statements designed to assist practitioners and patients in making decisions about appropriate heath care interventions. Clinical practice guidelines are expensive and time-consuming to create. A cpg on concurrent chemotherapy with radiation therapy (ccrt) was developed in Ontario at a time when treatment approaches for head-and-neck cancer were changing significantly. METHODS: An assessment of treatments and outcomes based on electronic and chart data obtained from a population-based study of 571 patients with oropharynx cancer treated in Ontario (2003-2004) was combined with a review of relevant knowledge transfer (publications and presentations at major meetings) to understand variation in adherence to a cpg. RESULTS: In 9 Ontario cancer treatment centres, ccrt was used for 55% of all patients with oropharyngeal cancer; however, at the centres individually, that proportion ranged from 82% to 39%. Furthermore, there was no agreement on the chemotherapy regimen: 2-4 years later (a period during which newer regimens were emerging), only 4 of 9 centres were following the guideline for most patients. When outcomes of treated patients were compared for centres with "higher" and "lower" use of ccrt, no difference in survival was observed (p = 0.64). CONCLUSIONS: At a time of treatment evolution, the new guideline was controversial, and there are many reasons for the mixed adherence. An estimation of adherence should be included during both development and review of guidelines.

Laryngeal cancer treatment and survival differences across regional cancer centres in Ontario, Canada.

AIMS: We conducted a population-based study of practice patterns and outcome across the regional cancer centres providing care to patients with laryngeal cancer in the Province of Ontario, Canada. MATERIALS AND METHODS: : This was a retrospective cohort study of 1547 patients with cancers of the glottic or supraglottic larynx diagnosed between 1982 and 1995. Data were collected via chart review, including: patient and disease characteristics, treatment, waiting times and treatment volumes. Vital status was obtained from the Ontario Cancer Registry. Variations across the nine regional cancer centres are described and their effect on outcome explored. All analyses were stratified by stage I and II separately from stage III and IV. RESULTS: Treatments differed across centres (P<0.0001); for instance, in the stage I and II group, use of a daily dose of >2.54Gy varied from 0 to 87.6% and in the stage III and IV group, total laryngectomy rates varied from a low of 6% to a high of 53%. The percentage of patients waiting more than 6 weeks from diagnosis to first treatment varied from 17 to 49% (P<0.0001). Multivariate analysis revealed cause-specific survival differences that were not explained by control for case mix, treatment or waiting times. Differences ranged from an 82% risk reduction in one centre compared with the reference (stage I and II group, P=0.008) to a 153% increase in risk (stage III and IV group, P=0.02). Centre case volumes were not associated with cause-specific survival. CONCLUSIONS: This study quantifies the degree of variation that can occur in the treatment and outcome of people with cancer. We cannot properly assess whether care delivery is of high quality until we have a better understanding of the factors that drive such variations.

Social support and quality of life of prostate cancer patients after radiotherapy treatment.

Research suggests that social support can have an impact on health-related quality of life (HRQOL). Social support can be structural support (SSS) or functional support (FSS). Our study was designed to clarify the relationships between HRQOL, FSS and SSS. We conducted a cross-sectional survey and a detailed chart review. The study population was men attending a follow-up clinic after receiving radiotherapy for prostate cancer. Functional social support was measured by using the MOS Social Support Survey. Structural social support was measured by using questions adapted from the 1994-1995 National Population Health Survey conducted by Statistics Canada. Health-related quality of life was measured by using the European Organization for Research and Treatment of Cancer's QLQ-C30. We found a statistically significant positive correlation between FSS and HRQOL but no association between overall SSS and HRQOL. Worsening urinary symptoms were significantly associated with lower levels of FSS and with lower HRQOL. This study underscores that the perception of support (functional) is more important than the amount or size of support (structural). We also identified a subgroup of men who have lower FSS and lower HRQOL that suffer from urinary side effects of their treatment. Further research to clarify the relationship between FSS and urinary symptoms will also clarify how an intervention could improve the HRQOL of these men.

Demographic differences between cancer survivors and those who die quickly of their disease.

AIMS: Some people diagnosed with cancer die extremely quickly of their disease. We investigated whether certain demographic and geographical characteristics were associated with these early deaths. MATERIALS AND METHODS: The Ontario Cancer Registry enhanced with census data was used to study early death in patients aged 40-69 years, diagnosed between 1990 and 1997 with colorectal, female breast, head and neck, lung, prostate, stomach, or primary cancer of unknown origin. For each site, cases were either those who constituted the quickest 10% of deaths, or those who died within 30 days, whichever was the larger number (n = 5022). Controls were those still alive at 1 year (n = 59 406). Analyses were stratified by disease site and logistic regression identified independent effects. Characteristics included: age, gender, area-level socioeconomic status, county of residence, urban/rural residence, diagnosis year, and distance to a cancer centre. RESULTS: Lower socioeconomic status (all sites) and increasing age (all sites except prostate and primary of unknown origin) were most strongly and consistently associated with early death. Male gender was a risk factor for early death from lung cancer. Living in urban areas was a risk factor for breast, lung, and unknown primary cancers. CONCLUSIONS: People living in poorer and/or urban areas and the young-elderly are more susceptible to a very late cancer diagnosis. Unequal access to cancer care can lead to devastating consequences for vulnerable sectors of society.

Explaining socioeconomic status effects in laryngeal cancer.

INTRODUCTION: People with lower socioeconomic status (SES) experience shorter survival times after a cancer diagnosis for many disease sites. We determined whether area-level SES was associated with the outcomes: cause-specific survival and local-regional failure in laryngeal cancer in Ontario, Canada. When we found an association we sought explanations that might be related to access to care including age, sex, rural residence, tumor stage, lymph node status, use of diagnostic imaging, treatment type, percentage of prescribed radiotherapy delivered, number of radiotherapy interruption days, treatment waiting time, and treating cancer center. MATERIALS AND METHODS: The study population consisted of 661 glottic and 495 supraglottic stage-stratified randomly-sampled patients identified using the Ontario Cancer Registry. Area-level SES quintiles were assigned using adjusted median household income from the Canadian Census. Other data were collected from patient charts. Explanations for SES effects were determined by measuring whether the effect moved toward the null value by at least 10% when an access indicator was added to a the model. RESULTS: Socioeconomic status was not related to either outcome for those with supraglottic cancer, but an association was present in glottic cancer. With the highest socioeconomic status quintile as the referent group, the relative risks for patients in the lowest socioeconomic quintile were 2.75 (95% CI 1.48, 5.12) for cause-specific survival and 1.90 (95% CI 1.24, 2.93) for local-regional failure. Disease stage as measured by T-category explained between 3% and 23% of these socioeconomic effects. None of the other access indicators met our 10% change criterion. CONCLUSION: We question why people in lower socioeconomic quintiles were not diagnosed earlier in the disease progression. Having ruled out several variables that may be related to access to care, additional biologic and social variables should be examined to further understand socioeconomic status effects.

Radiotherapy patterns of practice: T1N0 glottic cancer in Ontario, Canada.

AIMS: To describe the variation in the delivery of radiation therapy to patients with T1N0 glottic cancer who were diagnosed in Ontario, Canada, between 1982 and 1995. MATERIALS AND METHODS: The patient population consisted of a random sample of 461 patients treated with curative intent from the nine cancer centres that administer radiation therapy in the province. Abstracted variables included prescribed dose (Gy) and fractionation (f), beam energy and arrangement, set-up, field size, beam modifiers, positioning and treatment interruptions. RESULTS: Thirteen prescribed dose-fractionation schemes (> or = four cases each) were identified, including 50.0-53.0 Gy/20 f (54.5%), 55.0-61.0 Gy/25 f (30.3%), and 60.0-66.0 Gy/30-33 f (7.7%). All regimens used one fraction per day, 5 days per week. An isocentric set-up was used (94.3%), with megavoltage (MV) beam energies of Cobalt-60 (87.9%), 6 MV (6.1%) and 4 MV (6.1%). A lateral parallel-opposed pair of beams was the predominant technique (76.4%) versus an anterior oblique pair (17.2%) or angle-down pair (caudally directed fields to achieve shoulder clearance, 5.7%). Wedging (96.3%) and bolus (11.8%) were used as beam-modifying devices. Predominant field-width dimensions were 5.0-6.0 cm (43.4%) and 6.5-7.0 cm (43.1%), and field length dimensions were 5.0-6.0 cm (49.5%) and 6.5-7.0 cm (35.0%). Head, neck or chin immobilisation was used in 86.9% of the cases, with 94.6% of these being custom-made. We found that radiotherapy practice was stable over time, except for a trend of increasing field size and increasing use of immobilisation. In contrast, we found practice variations among the province's cancer centres. On the basis of our findings, we defined a predominant technical practice consisting of Cobalt-60 (reflecting machine availability during the period of the study), an isocentric set-up, a lateral parallel-opposed pair technique with wedging, and supine-head neutral positioning with custom immobilisation. Forty-two per cent of the cases had one or more components of treatment that differed from this definition. CONCLUSIONS: Description of practice variation can provoke discussion about unrecognised differences in practice policies, perhaps identifying the need for better evidence, treatment guidelines, or both.

Time spent in hospital in the last six months of life in patients who died of cancer in Ontario.

PURPOSE: To describe hospital bed utilization in the final 6 months of life in patients dying of cancer in Ontario, Canada. PATIENTS AND METHODS: Hospital separation records were linked to a population-based cancer registry to identify factors associated with hospitalization in the 203,713 patients who died of cancer in Ontario between 1986 and 1998. RESULTS: Between 1986 and 1998, 5.3% of all acute care beds in Ontario were devoted to the care of cancer patients in the last 6 months of life. The mean time spent in hospital in the last 6 months of life decreased from 34.3 days in 1986 to 22.7 days in 1998. Hospitalization rates increased exponentially during the last month of life. Patients younger than 50 years of age, women, and residents of poorer communities spent significantly longer in hospital than others. Hospitalization rates differed very little among the common solid tumors, but patients with CNS malignancies, the lymphomas, and the leukemias spent significantly longer in hospital than the other groups. There was significant interregional variations in hospitalization that were not explained by differences in case mix. There was a statistically significant inverse correlation between the rate of use of palliative radiotherapy and the hospital bed use in the county in which the patient resided. CONCLUSION: The total time spent in hospital in the last 6 months of life has decreased over the last decade, but acute care hospitals continue to play a large role in the care of patients who are dying of cancer.

A comparison of published head and neck stage groupings in carcinomas of the tonsillar region.

BACKGROUND: The combination of T, N, and M classifications into stage groupings was designed to facilitate a number of activities including: the estimation of prognosis and the comparison of therapeutic interventions among similar groups of cases. The authors tested the UICC/AJCC 5th edition stage grouping and seven other TNM-based groupings proposed for head and neck cancer to determine their ability to meet these expectations in a specific site: carcinoma of the tonsillar region. METHODS: The authors defined four criteria to assess each stage grouping scheme: 1) The subgroups defined by T and N comprising a given group within a grouping scheme have similar survival rates (hazard consistency); 2) The survival rates differ across the groups (hazard discrimination); 3) The prediction of cure is high (outcome prediction); and 4) The distribution of patients among the groups is balanced. The authors identified or derived a measure for each criterion and the findings were summarized using a scoring system. The range of scores was from 0 (best) to 7 (worst). Data were from a retrospective chart review on 642 cases of carcinoma of the tonsillar region treated with radiotherapy for cure at the Princess Margaret Hospital from 1970-1991. None of the patients had distant metastases. RESULTS: The scheme proposed by Synderman and Wagner, which was published in Otolaryngology Head and Neck Surgery in 1995 (vol.112, pages 691-4), scored best at 1.2. The UICC/AJCC scheme scored worst at 6.1. The hazard consistency ranged from a 3.1% average survival difference to 6.7% across the 8 schemes. The hazard discrimination measure varied by 28% from the best to worst scheme. Prediction varied by up to almost twofold across the schemes assessed. The distribution of patients varied from expected by between 0.13% and 0.57%. CONCLUSION: UICC/AJCC stage groupings were defined without empirical investigation. When tested, this scheme did not perform as well as any of seven empirically-derived schemes the authors evaluated. The results of the current study suggest that the usefulness of the TNM system can be enhanced by optimizing the design of stage groupings through empirical investigation.

A comparison of published head and neck stage groupings in carcinomas of the oral cavity.

BACKGROUND: The combination of T, N, and M classifications into stage groupings is meant to facilitate a number of activities, including the estimation of prognosis and the comparison of therapeutic interventions among similar groups of cases. We tested the UICC/AJCC 5th edition stage grouping and seven other TNM-based groupings proposed for head and neck cancer for their ability to meet these expectations in a specific site: carcinomas of the oral cavity. METHODS: We defined four criteria to assess each grouping scheme: (1) the subgroups defined by T, N, and M that make up a given group within a grouping scheme have similar survival rates (hazard consistency); (2) the survival rates differ among the groups (hazard discrimination); (3) the prediction of cure is high (outcome prediction); and (4) the distribution of patients among the groups is balanced. We identified or derived a measure for each criterion, and the findings were summarized by use of a scoring system. The range of scores was from 0 (best) to 7 (worst). The data are population based from a prospectively gathered series in Southern Norway, with 556 patients diagnosed from 1983 through 1995. Clinical stage assignment was used, and the outcome of interest was cause-specific survival. RESULTS: Summary scores across the eight schemes ranged from 1.66 for TANIS-3 to 6.50 for UICC/AJCC-5. The TANIS-7 staging scheme performed best on the hazard consistency criterion. The Kiricuta scheme performed best on the hazard discrimination criterion. Synderman predicted outcome best overall and Berg produced the most balanced distribution of cases among its groups. CONCLUSIONS: UICC/AJCC stage groupings were defined without empirical investigation. When tested, this scheme did not perform as well as any of seven empirically derived schemes we evaluated. Our results suggest that the usefulness of the TNM system could be enhanced by optimizing the design of stage groupings through empirical investigation.

The role of computed tomography in the T classification of laryngeal carcinoma.

BACKGROUND: The objectives of this study were 1) to describe patterns of use of computed tomography (CT) in laryngeal carcinoma, and 2) to characterize the contribution of CT to the T classification of laryngeal carcinoma. METHODS: The study population comprised 1195 patients with laryngeal carcinoma diagnosed from 1982 through 1995 chosen randomly from the Ontario provincial cancer registry. A chart review was conducted to obtain data on each case. Patient-related, tumor-related, and health-system-related factors were analyzed to identify factors associated with the use of CT. Descriptions of clinical exams and CT reports were reviewed to see how CT information modified T classification. Actuarial local control and cause specific survival curves were plotted by clinical T classification without and with CT to evaluate stage migration. The percentage of the variance in outcome explained by T classification in a Cox analysis was used to evaluate whether the prognostic accuracy of T classification was improved with the use of information from CT. RESULTS: Patients with glottic (20.1%) and supraglottic (41.7%) carcinoma underwent CT. The use of CT increased over time in glottic and supraglottic carcinoma combined from 17.2% in 1982-5 to 33.9% in 1991-5. Computed tomography was used less often in older patients with a 16% (95% confidence interval, 5-27%) decrease in the odds of having CT with each 10-year age increment. Computed tomography use varied considerably across the cancer center regions in Ontario. Computed tomography altered the T classification in 20.2% of those patients who had CT, with most being "upstages." Stage migration due to CT was demonstrated. Using information from CT in the assignment of T classification for 27.8% of this study population did not make a significant contribution to the ability of T classification to predict outcome over the entire group. CONCLUSIONS: There is large variation in the use of CT among different age groups and regions. The ability to compare outcomes by stage across geographic areas is compromised when the use of CT varies.

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.

Time to first relapse as an outcome and a predictor of survival in patients with squamous cell carcinoma of the head and neck.

OBJECTIVE: To identify patterns and predictors of relapse and to determine whether the time to relapse influences survival. STUDY DESIGN: Multivariate anal. ysis of prospective database. METHODS: We present findings in 446 consecutive prospective patients from a regional cancer center with invasive squamous cell carcinoma who were treated for cure and were declared disease free. Time to relapse, site of relapse, and survival are reported by stage and site using bivariate and multivariate analysis. RESULTS: Thirty-six percent of patients relapsed. The median time to relapse was 8.3 months, and 95% of relapses occurred within 3 years. T stage in the TNM staging system was associated with relapse, and N stage was not. In patients who relapsed before the median time to relapse, prognosis was worse than in those who relapsed after that time.

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.