Cancer incidence, mortality, and stage at diagnosis in First Nations living in Manitoba

BACKGROUND

In the present study, we examined breast (bca) and colorectal cancer (crc) incidence and mortality and stage at diagnosis for First Nations (fn) individuals and all other Manitobans (aoms).

METHODS

Several population-based databases were linked to determine ethnicity and to calculate age-standardized incidence and mortality rates. Logistic regression was used to compare bca and crc stage at diagnosis.

RESULTS

From 1984-1988 to 2004-2008, the incidence of bca increased for fn and aom women. Breast cancer mortality increased for fn women and decreased for aom women. First Nations women were significantly more likely than aom women to be diagnosed at stages iii-iv than at stage i [odds ratio (or) for women ≤50 years of age: 3.11; 95% confidence limits (cl): 1.20, 8.06; or for women 50-69 years of age: 1.72; 95% cl: 1.03, 2.88). The incidence and mortality of crc increased for fn individuals, but decreased for aoms. First Nations status was not significantly associated with crc stage at diagnosis (or for stages i-ii compared with stages iii-iv: 0.98; 95% cl: 0.68, 1.41; or for stages i-iii compared with stage iv: 0.91; 95% cl: 0.59, 1.40).

CONCLUSIONS

Our results underscore the need for improved cancer screening participation and targeted initiatives that emphasis collaboration with fn communities to reduce barriers to screening and to promote healthy lifestyles.

Radiation treatment waiting times for breast cancer patients in Manitoba, 2001 and 2005

INTRODUCTION

Our study examined the wait time from ready-to-treat to radiation therapy for cohorts of breast cancer patients requiring adjuvant radiation therapy in 2001 and in 2005 after the implementation of strategies to reduce wait times for radiation treatment. We also examined the overall time from diagnosis to radiation treatment and whether distance from the cancer treatment centre or month of referral had an effect on wait times.

METHODS

This population-based retrospective study looked at representative samples of women newly diagnosed with breast cancer in 2001 and 2005. Patients who required radiation treatment to the breast or chest wall were followed from first contact to the start of radiation treatment.

RESULTS

Time from ready-to-treat to first radiation treatment was significantly reduced for patients in 2005 as compared with 2001, regardless of whether chemotherapy was administered before radiation treatment. Time from diagnosis to radiation treatment was not different by year for those who received radiation only. Time from diagnosis to chemotherapy was significantly longer in 2005. No effect of month of diagnosis on wait times was observed.

INTERPRETATION

A significant improvement in the median wait time from ready-to-treat to first radiation treatment was noted from 2001 to 2005. This improvement may be attributable to measures taken to reduce such waits. However, we observed an increase in the median time from diagnosis to referral and from referral to consultation with medical or radiation oncology (or both), so that the overall time from diagnosis to radiation treatment was not different. Although specific intervals related to radiation treatment delivery were improved, the entire trajectory of breast cancer care experienced by patients needs to be considered.

Same question, different data source, different answers? Data source agreement for surgical procedures on women with breast cancer

This study assessed the accuracy of the Manitoba Cancer Registry (MCR) and two administrative data sources, the Manitoba Health hospital discharge file and the Manitoba Health medical claims file, for capturing surgical procedures related to the treatment of breast cancer. The study cohort included all women diagnosed in Manitoba with invasive or in situ breast cancer between 1995 and 1999. The surgical procedures of interest were mastectomy, breast conserving surgery and axillary node dissection. Analysis focused on assessing concordance between data sources following record linkage. Agreement was measured using the kappa statistic, and chart reviews of discordant information were completed to identify the more reliable data source and to validate data files. The effect of using each data set alone to calculate procedure rates was determined to identify any clinically important differences arising from the choice of data source. Results indicate that capture of breast cancer patients using administrative data sets alone can be quite good and that the population-based cancer registry is superior to other administrative data sets for capturing surgical treatment information on cancer cases.