Does diabetes affect breast cancer survival?

OBJECTIVES: The objective of this study is to investigate the influence of diabetes on breast cancer-specific survival among women with breast cancer in Aotearoa/New Zealand. METHODS: This study included women diagnosed with invasive breast cancer between 2005 and 2020, with their information documented in the Te Rehita Mate Utaetae-Breast Cancer Foundation National Register. Breast cancer survival curves for women with diabetes and those without diabetes were generated using the Kaplan-Meier method. The hazard ratio (HR) of breast cancer-specific mortality for women with diabetes compared to women without diabetes was estimated using the Cox proportional hazards model. RESULTS: For women with diabetes, the 5-year and 10-year of cancer-specific survival were 87% (95% CI: 85%-88%) and 79% (95% CI: 76%-81%) compared to 89% (95% CI: 89%-90%) and 84% (95% CI: 83%-85%) for women without diabetes. The HR of cancer-specific mortality for patients with diabetes compared to those without diabetes was 0.99 (95% CI: 0.89-1.11) after adjustment for patient demographics, tumor characteristics, and treatments. Age at cancer diagnosis and cancer stage had the biggest impact on the survival difference between the two groups. When stratified by cancer stage, the cancer-specific mortality between the two groups was similar. CONCLUSIONS: While differences in survival have been identified for women with diabetes when compared to women without diabetes, these are attributable to age and the finding that women with diabetes tend to present with more advanced disease at diagnosis. We did not find any difference in survival between the two groups due to differences in treatment.

The growing cancer burden: Age-period-cohort projections in Aotearoa New Zealand 2020-2044.

BACKGROUND: Cancer is a major cause of premature death and inequity, and global case numbers are rapidly expanding. This study projects future cancer numbers and incidence rates in Aotearoa New Zealand. METHODS: Age-period-cohort modelling was applied to 25-years of national data to project cancer cases and incidence trends from 2020 to 2044. Nationally mandated cancer registry data and official historical and projected population estimates were used, with sub-groups by age, sex, and ethnicity. RESULTS: Cancer diagnoses were projected to increase from 25,700 per year in 2015-2019 to 45,100 a year by 2040-44, a 76% increase (2.3% per annum). Across the same period, age-standardised cancer incidence increased by 9% (0.3% per annum) from 348 to 378 cancers per 100,000 person years, with greater increases for males (11%) than females (6%). Projected incidence trends varied substantially by cancer type, with several projected to change faster or in the opposite direction compared to projections from other countries. CONCLUSIONS: Increasing cancer numbers reinforces the critical need for both cancer prevention and treatment service planning activities. Investment in developing new ways of working and increasing the workforce are required for the health system to be able to afford and manage the future burden of cancer.

Ethnic differences in the characteristics of patients with newly diagnosed lung cancer in the Te Manawa Taki region of New Zealand.

BACKGROUND: Maori have three times the mortality from lung cancer compared with non-Maori. The Te Manawa Taki region has a population of 900 000, of whom 30% are Maori. We have little understanding of the factors associated with developing and diagnosing lung cancer and ethnic differences in these characteristics. AIMS: To explore the differences in the incidence and characteristics of patients with newly diagnosed lung cancer between Maori and non-Maori. METHODS: Patients were identified from the regional register. Incidence rates were calculated based on population data from the 2013 and 2018 censuses. The patient and tumour characteristics of Maori and non-Maori were compared. The analysis used Χ2 tests and logistic models for categorical variables and Student t tests for continuous variables. RESULTS: A total of 4933 patients were included, with 1575 Maori and 3358 non-Maori. The age-standardised incidence of Maori (236 per 100 000) was 3.3 times higher than that of non-Maori. Maori were 1.3 times more likely to have an advanced stage of disease and 1.97 times more likely to have small cell lung cancer. Maori were more likely to have comorbidities, chronic obstructive pulmonary disease, cardiovascular disease and diabetes. They also had higher levels of social deprivation and tended to be younger, female and current smokers. CONCLUSIONS: The findings point to the need to address barriers to early diagnosis and the need for system change including the need to introduce a lung cancer screening focussing on Maori. There is also the need for preventive programmes to address comorbidities that impact lung cancer outcomes as well as a continued emphasis on creating a smoke-free New Zealand.

Non-small cell lung cancer chemotherapy treatment outcomes and ethnicity: a twenty-year single-centre patterns of care study.

AIM: To investigate the treatment of patients with advanced-stage non-small cell lung cancer (NSCLC) over a 20-year period in a single Aotearoa New Zealand centre with reference to the use of systemic anti-cancer chemotherapy (SACT) and to explore ethnic disparities in treatment and outcomes. METHOD: Using a SACT database maintained by the Oncology Department at Waikato Hospital, Hamilton, Aotearoa New Zealand from 2000 to 2021 we derived summary statistics for patient factors and SACT regimens by ethnicity (Maori and non-Maori). We investigated Kaplan-Meier all-cause survival by ethnicity and SACT. Logistic regression was used to estimate the odds ratios of surviving 12 months and receiving first and second SACT. RESULTS: One thousand and fifty-seven patients with advanced NSCLC were included, with 30% identified as Maori and 53% treated with SACT. The median survival for non-Maori and Maori receiving SACT was 11.9 and 8.5 months respectively (unadjusted odds ratio of surviving 12 months: 1.968; 95% CI: 1.352-2.865; p<0.001). Non-Maori receiving SACT were 86.2% more likely to survive 12 months than Maori. There were no ethnic disparities in the proportion of patients receiving first-line SACT; however, non-Maori were 1.5 times more likely to receive a second SACT than Maori. CONCLUSION: Significant ethnic difference between Maori and non-Maori exists for both survival and receipt of second-line SACT.

Equity of Cancer and Diabetes Co-Occurrence: A National Study With 44 Million Person-Years of Follow-Up.

PURPOSE: The co-occurrence of diabetes and cancer is becoming increasingly common, and this is likely to compound existing inequities in outcomes from both conditions within populations. METHODS: In this study, we investigate the co-occurrence of cancer and diabetes by ethnic groups in New Zealand. National-level diabetes and cancer data on nearly five million individuals over 44 million person-years were used to describe the rate of cancer in a national prevalent cohort of peoples with diabetes versus those without diabetes, by ethnic group (Maori, Pacific, South Asian, Other Asian, and European peoples). RESULTS: The rate of cancer was greater for those with diabetes regardless of ethnic group (age-adjusted rate ratios, Maori, 1.37; 95% CI, 1.33 to 1.42; Pacific, 1.35; 95% CI, 1.28 to 1.43; South Asian, 1.23; 95% CI, 1.12 to 1.36; Other Asian, 1.31; 95% CI, 1.21 to 1.43; European, 1.29; 95% CI, 1.27 to 1.31). Maori had the highest rate of diabetes and cancer co-occurrence. Rates of GI, endocrine, and obesity-related cancers comprised a bulk of the excess cancers occurring among Maori and Pacific peoples with diabetes. CONCLUSION: Our observations reinforce the need for the primordial prevention of risk factors that are shared between diabetes and cancer. Also, the commonality of diabetes and cancer co-occurrence, particularly for Maori, reinforces the need for a multidisciplinary, joined-up approach to the detection and care of both conditions. Given the disproportionate burden of diabetes and those cancers that share risk factors with diabetes, action in these areas is likely to reduce ethnic inequities in outcomes from both conditions.

Impact of diabetes on surgery and radiotherapy for breast cancer.

PURPOSES: This study aims to examine whether diabetes has an impact on the use of surgery and adjuvant radiotherapy in treating women with localised breast cancer. METHODS: Women diagnosed with stage I-III breast cancer between 2005 and 2020 were identified from Te Rehita Mate Utaetae-Breast Cancer Foundation New Zealand National Register, with diabetes status determined using New Zealand's Virtual Diabetes Register. The cancer treatments examined included breast conserving surgery (BCS), mastectomy, breast reconstruction after mastectomy, and adjuvant radiotherapy after BCS. Logistic regression modelling was used to estimate the adjusted odds ratio (OR) and 95% confidence interval (95% CI) of having cancer treatment and treatment delay (> 31 days) for patients with diabetes at the time of cancer diagnosis compared to patients without diabetes. RESULTS: We identified 25,557 women diagnosed with stage I-III breast cancer in 2005-2020, including 2906 (11.4%) with diabetes. After adjustment for other factors, there was no significant difference overall in risk of women with diabetes having no surgery (OR 1.12, 95% CI 0.94-1.33), although for patients with stage I disease not having surgery was more likely (OR 1.45, 95% CI 1.05-2.00) in the diabetes group. Patients with diabetes were more likely to have their surgery delayed (adjusted OR of 1.16, 95% CI 1.05-1.27) and less likely to have reconstruction after mastectomy compared to the non-diabetes group-adjusted OR 0.54 (95% CI 0.35-0.84) for stage I cancer, 0.50 (95% CI 0.34-0.75) for stage II and 0.48 (95% CI 0.24-1.00) for stage III cancer. CONCLUSIONS: Diabetes is associated with a lower likelihood of receiving surgery and a greater delay to surgery. Women with diabetes are also less likely to have breast reconstruction after mastectomy. These differences need to be taken in to account when considering factors that may impact on the outcomes of women with diabetes especially for Maori, Pacific and Asian women.

What affects the public healthcare costs of breast cancer in New Zealand?

BACKGROUNDS: The pressure to the healthcare system for providing ongoing monitoring and treatment for breast cancer survivors is increasing. This study aims to identify the factors that affect the public healthcare costs of stage I-III breast cancer and stage IV cancer in New Zealand. METHODS: We identified women diagnosed with invasive breast cancer between July 1, 2010 and June 30, 2018 and who received services in a public hospital. Patients were identified from the National Breast Cancer Register and/or New Zealand Cancer Registry and were linked to the national administrative datasets. A two-part model was used to identify the factors that affect the public healthcare costs of stage I-III breast cancer and stage IV cancer. RESULTS: We identified 16,977 stage I-III and 1,093 stage IV breast cancer patients eligible for this study. The costs of stage I-III cancer in the second to fifth year post diagnosis decreased over time, and the costs of stage IV cancer in the first year post diagnosis increased over time. After adjustment for other factors, the costs of stage I-IV cancer decreased with age but increased with cancer stage. HER2+ cancers had the highest costs, followed by triple negative cancers. After adjustment for other factors, Pacific and Asian women had lower costs, and Maori had similar costs compared to others. For stage I-III cancers, women living in nonmajor urban areas had a higher chance of incurring costs in follow-up years, and screen detected patients and patients having any services in a private hospital had a decreased probability of receiving any public healthcare services. CONCLUSIONS: Pacific women had higher costs than others, but after adjustment for cancer stage, subtype, and other factors, they had lower costs than others. The early detection and better management of stage I-III breast cancer can lead to better outcome and lower costs in follow-up years.

Association of diabetes and breast cancer characteristics at diagnosis.

PURPOSE: This study aims to examine the association of diabetes and breast cancer characteristics at diagnosis in Aotearoa/New Zealand. METHODS: Patients diagnosed with invasive breast cancer between 2005 and 2020 were identified from the National Breast Cancer Register. Logistic regression modeling was used to estimate the adjusted odds ratio (OR) of having stage III-IV cancer and the OR of having stage IV cancer for women with diabetes compared to those without diabetes. The adjusted OR of having screen-detected breast cancers for patients aged 45-69 years with diabetes compared to patients without diabetes was estimated. RESULTS: 26,968 women were diagnosed with breast cancer, with 3,137 (11.6%) patients having diabetes at the time of cancer diagnosis. The probability of co-occurrence of diabetes and breast cancer increased with time. Maori, Pacific and Asian women were more likely to have diabetes than European/Others. The probability of having diabetes also increased with age. For patients with diabetes, the probability of being diagnosed with stage III-IV cancer and stage IV cancer was higher than for patients without diabetes (OR 1.14, 95% CI 1.03-1.27; and 1.17, 95% CI 1.00-1.38). Women aged 45-69 years with diabetes were more likely to have screen-detected cancer than those without diabetes (OR 1.13, 95% CI 1.02-1.26). CONCLUSIONS: The co-occurrence of diabetes and breast cancer is becoming more common. Overall there is a small but significant adverse impact of having advanced disease for women with diabetes that is found at the time of breast cancer diagnosis, and this may contribute to other inequities that occur in the treatment pathway that may impact on patient outcomes.

Cancer and diabetes co-occurrence: A national study with 44 million person-years of follow-up.

The number of new cases of cancer is increasing each year, and rates of diabetes mellitus are also increasing dramatically over time. It is not an unusual occurrence for an individual to have both cancer and diabetes at the same time, given they are both individually common, and that one condition can increase the risk of the other. In this manuscript, we use national-level diabetes (Virtual Diabetes Register) and cancer (New Zealand Cancer Registry) data on nearly five million individuals over 44 million person-years of follow-up to examine the occurrence of cancer amongst a national prevalent cohort of patients with diabetes. We completed this analysis separately by cancer for the 24 most commonly diagnosed cancers in Aotearoa New Zealand, and then compared the occurrence of cancer among those with diabetes to those without diabetes. We found that the rate of cancer was highest amongst those with diabetes for 21 of the 24 most common cancers diagnosed over our study period, with excess risk among those with diabetes ranging between 11% (non-Hodgkin's lymphoma) and 236% (liver cancer). The cancers with the greatest difference in incidence between those with diabetes and those without diabetes tended to be within the endocrine or gastrointestinal system, and/or had a strong relationship with obesity. However, in an absolute sense, due to the volume of breast, colorectal and lung cancers, prevention of the more modest excess cancer risk among those with diabetes (16%, 22% and 48%, respectively) would lead to a substantial overall reduction in the total burden of cancer in the population. Our findings reinforce the fact that diabetes prevention activities are also cancer prevention activities, and must therefore be prioritised and resourced in tandem.

Differences in Breast Cancer Costs by Cancer Stage and Biomarker Subtype in New Zealand.

BACKGROUND: Breast cancer requires the greatest expenditure among all cancer types, and the costs vary by cancer stage and biomarker status. OBJECTIVE: This study aimed to examine the differences in public healthcare costs of breast cancer in New Zealand by stage and subtype. METHOD: This study included patients diagnosed with invasive breast cancer between 1 July 2010 and 30 June 2018 and receiving services in public hospitals. These patients were identified from the National Breast Cancer Register and/or New Zealand Cancer Registry. Linking with the Pharmaceutical Collection, National Minimum Dataset, National Non-Admitted Patient Collection, and Mortality Collection, we estimated the median public healthcare costs of breast cancer by cancer stage and biomarker subtype. RESULTS: We identified 22,948 eligible patients. The median costs of breast cancer increased with stage of disease, from $NZ26,930 for stage I disease to $NZ50,388 for stage IV disease. The median costs for human epidermal growth factor receptor 2-positive (HER2+) disease were three times those for HER2-negative (HER2-) disease: $NZ106,428 for HER2+ cancers compared with$NZ28,481 for oestrogen receptor-positive (ER+)/HER2- cancers and $NZ31,722 for triple negative disease. Over 55% of the costs for HER2+ breast cancers were targeted therapy costs. For HER2- cancers, surgery incurred the biggest cost, followed by radiotherapy. CONCLUSIONS: Treating patients with early-stage breast cancer is less costly than treating those with metastatic disease. The costs vary considerably between the subtypes. Patients with HER2+ cancer incurred three times the costs of those with HER2- cancers. These results provide baseline costing data for clinicians and policy makers when considering new targeted treatments.

Outcomes from colonoscopy following referral from New Zealand general practice: a retrospective analysis.

BACKGROUND: New Zealand has high rates of colorectal cancer (CRC) but poor outcomes. Most patients with CRC are diagnosed following referral from general practice, where a general practitioner (GP) assesses symptoms according to national guidelines. All referred patients are then re-prioritised by the hospital system. The first objective of this study was to identify what proportion of patients referred by general practice to surgical/gastroenterology at Waikato District Health Board (DHB) had a colonoscopy. The second objective was to determine what proportion of these referrals have an underlying CRC and the factors associated with the likelihood of this diagnosis. METHODS: This study is a retrospective analysis of e-referral data for patients aged 30-70+ who were referred from 75 general practices to general surgery, gastroenterology or direct to colonoscopy at Waikato DHB, 01 January 2015-31 December 2017. Primary and secondary outcome measures included the proportion and characteristics of patients who were having colonoscopy, and of those, who were diagnosed with CRC. Data were analysed using chi square and logistic regression. RESULTS: 6718/20648 (32.5%) patients had a colonoscopy and 372 (5.5%) of these were diagnosed with CRC. The probability of having CRC following a colonoscopy increased with age (p value < 0.001). Females (p value < 0.001), non-Maori (p value < 0.001), and patients with a high suspicion of cancer (HSCan) label originating from their GP were more likely to have a colonoscopy, while the odds ratio of Maori having a colonoscopy was 0.66 (95% CI 0.60-0.73). The odds ratio of a CRC diagnosis following colonoscopy was 1.67 (95% CI 1.35-2.07) for men compared to women, and 2.34 (95% CI 1.70-3.22) for those with a GP HSCan label. Of the 585 patients referred with a GP HSCan, 423 (72.3%) were reprioritised by the hospital and 55 patients had their diagnosis unnecessarily delayed. CONCLUSIONS: If a GP refers a patient with an HSCan, and the patient receives a colonoscopy, then the likelihood of having CRC is almost 15.0%. This would suggest that these patients should be routinely prioritised without further triage by the hospital. Further research is needed to understand why Maori are less likely to receive a colonoscopy following referral from general practice.

Breast cancer costs in New Zealand's public health system.

AIM: This study aims to estimate the mean costs of breast cancer in New Zealand's public health system. METHOD: This study included women diagnosed with invasive breast cancer between 1 July 2010 and 30 June 2018 who received services in public hospitals. These patients were identified from the National Breast Cancer Register or the New Zealand Cancer Registry and linked with the Pharmaceutical Collection, National Minimum Dataset, National Non-Admitted Patient Collection and Mortality Collection. RESULTS: 22,948 breast cancer patients were included. The mean public health cost of breast cancer was NZ$44,954 per patient for the period of three months preceding and five years following cancer diagnosis, with the treatment phase accounting for 70% of the cost and the follow-up phase accounting for the remaining 30%. During the treatment phase, surgery costs accounted for the biggest proportion (35%) of the total cost, followed by immunotherapy costs (18%), radiotherapy costs (17%) and costs of diagnostic test, scan and biopsy (16%). The costs decreased substantially with age, from $69,121 for women younger than 45 years old to $23,805 for those aged 80 or over. CONCLUSIONS: The costs of breast cancer in New Zealand's public health system are substantial and have been increasing. However, outcomes of breast cancer have been improving. The results of this study can be used as a baseline of actual costs for comparing the costs of introducing new diagnosis and treatment modalities in the future.

Use and results of systemic treatments for de novo and recurrent metastatic breast cancer: a population-based cohort study.

AIMS: To describe the systemic treatments in patients with de novo metastatic breast cancer (dnMBC, initial metastatic diagnosis) and recurrent metastatic breast cancer (rMBC). METHODS: Women diagnosed with dnMBC and rMBC in 2010-2017 were identified. Adjusted odds ratios of receiving systemic treatments were estimated by logistic regression model. Cox proportional hazards regression was used to estimate adjusted hazard ratio of breast cancer-specific mortality by treatments. RESULTS: The adjusted odds ratio of having chemotherapy and trastuzumab (for human epidermal growth factor receptor 2 positive (HER2+) disease) for Pacific women was 0.43 and 0.13 compared to European women. Patients receiving chemotherapy had improved survival for HER2+ non-luminal and triple negative metastatic breast cancer (MBC) (hazard ratios: 0.30, 0.66). Those with endocrine therapy was associated with better survival for luminal A and luminal B HER2+ MBC (hazard ratio: 0.25, 0.26). Trastuzumab was associated with superior survival in luminal B HER2+ and HER2+ non-luminal disease (hazard ratio: 0.34, 0.40). CONCLUSIONS: Pacific women with MBC were less likely to receive chemotherapy and trastuzumab than non-Pacific women. Chemotherapy was associated with improved survival in HER2+ non-luminal and triple negative MBC. Endocrine therapy improved survival in luminal A and luminal B HER2+ disease. Trastuzumab was associated with improved survival in luminal B HER2+ and HER2+ non-luminal disease.

Impact of menopausal status on risk of metastatic recurrence of breast cancer.

OBJECTIVE: Menopausal status at diagnosis is an important factor for the management of breast cancer in younger women, and may affect the prognosis for these women. We aim to examine the association of menopausal status and risk of metastatic relapse for stage I-III breast cancer. METHODS: We included women diagnosed with stage I-III breast cancer at 45 to 55 years in the Auckland and Waikato Breast Cancer Registers. Cumulative incidence of metastatic relapse was examined by age group and by menopausal status after stratifying by estrogen receptor (ER) and progesterone receptor (PR) status. Cox proportional hazards model was used to estimate the adjusted hazard ratio of metastatic relapse by menopausal status after adjustment for age, ethnicity, year of diagnosis, socioeconomic status, public/private hospital treatment, mode of detection, cancer stage, grade and human epidermal growth factor receptor 2 status. RESULTS: We have identified 5,309 eligible women: 2,799 premenopausal, 929 perimenopausal, and 1,581 post-menopausal. There was significant difference in risk of metastatic recurrence between menopausal statuses for ER+ and/or PR+ cases, with a 10-year cumulative incidence of 11.2% for premenopausal, 12.4% for perimenopausal, and 15.6% for postmenopausal women. The adjusted hazard ratio of metastatic recurrence for postmenopausal compared to premenopausal women was 1.38 for ER+ and/or PR+ cases. Age did not affect the risk of metastatic relapse for ER+ and/or PR+ cases but affected the risk for ER- and PR- cases with a hazard ratio of 0.94 per year. CONCLUSIONS: Women with earlier age at menopause, and ER+ and/or PR+ stage I-III breast cancer were more likely to develop metastatic breast cancer. Age increased the risk of metastatic relapse for women with ER- and PR- disease, but not for ER+ and/or PR+ cancers.

Metastatic relapse of stage I-III breast cancer in New Zealand.

PURPOSE: This study aims to investigate the factors that influence the risk of metastatic relapse in women presenting with stage I-III breast cancer in New Zealand. METHODS: The study included women diagnosed with stage I-III breast cancer. Cumulative incidence of distant metastatic relapse was examined with the Kaplan-Meier method by cancer stage and subtype. Cox proportional hazards models were used to estimate the adjusted hazard ratio of developing recurrent metastatic breast cancer by cancer stage and biomarker subtype after adjustment for other factors. RESULTS: A total of 17,543 eligible women were identified. The 5-year cumulative incidence of metastatic recurrence was 3.7% for stage I, 13.3% for stage II and 30.9% for stage III disease. The adjusted hazard ratios (HR) of stage II and stage III breast cancer developing metastatic disease were 2.07 and 4.82 compared to stage I. The adjusted risk of distant metastatic relapse was highest for luminal B HER2- cancers (adjusted HR: 1.59 compared to luminal A disease). Higher grade cancers were associated with a higher risk of metastases. After adjustment, women aged 60-69 years and Asian women had the lowest risk of distant metastatic relapse. CONCLUSIONS: The prognosis of women with locally invasive breast cancer differs greatly with the chance of developing metastatic disease depending on the stage of disease at diagnosis and the subtype. Grade of disease at diagnosis was also important. Maori or Pacific ethnicity did not influence the risk of developing metastatic disease, although Asian women seemed less likely to develop metastases.

Characteristics and survival of de novo and recurrent metastatic breast cancer in New Zealand.

BACKGROUND: We aim to examine the characteristics and survival of patients with de novo metastatic breast cancer (dnMBC) and recurrent metastatic breast cancer (rMBC) in New Zealand. METHODS: This study included women diagnosed with dnMBC and women who developed rMBC between 2010 and 2017. The Kaplan-Meier method was used to examine cancer-specific survival. Cox proportional hazards regression was used to estimate the adjusted hazard ratio (HR) of cancer-specific mortality by ethnicity, age, year of diagnosis, socioeconomic deprivation, site of metastases, number of metastatic sites, biomarker subtype and MBC subgroup. RESULTS: We included 2177 MBC patients (667 dnMBC and 1510 rMBC). The median survival of dn MBC patients was 26 months compared to 18 months for rMBC. There were no differences in breast-cancer specific mortality by ethnicity or socioeconomic deprivation. The adjusted HR for patients with visceral metastases compared to patients with non-visceral metastases was 1.41, and the adjusted HR for triple negative disease compared to Luminal A disease was 2.24. Compared to dnMBC, the adjusted HRs for rMBC patients with a metastatic-free interval of < 2 years, 2-4 years, 5-7 year and 8 + years were 1.81, 1.47, 1.08 and 0.82, respectively. CONCLUSIONS: The survival for patients with MBC in New Zealand is very similar to other developed countries. Patients with dnMBC had a much better prognosis than those with recurrent disease. Patients with triple negative disease or non-luminal HER2 positive disease had the worst prognosis. The prognosis for patient with rMBC improved the longer the time from diagnosis to the development of metastases.

Evidence of inequitable use of chemotherapy in New Zealand colorectal cancer patients.

AIMS: To explore variations in the use of and timeliness of chemotherapy in patients diagnosed with colorectal cancer in New Zealand. METHODS: This study included patients diagnosed with colorectal cancer in New Zealand between 1 January 2006 and 31 December 2016. The first chemotherapy regime was identified from Pharmaceutical Collection dataset. Logistic regression model was used to estimate the adjusted odds ratio of having chemotherapy by subgroup after adjustment for other factors. RESULTS: 27.8% (6,737/24,217) of colon cancer patients and 43.8% (3,582/8,170) of rectal cancer patients received publicly funded chemotherapy. The uptake and timeliness of chemotherapy has been improving over time. Pacific people were the least likely to receive chemotherapy, followed by Maori and Asian. Younger patients, New Zealand European, patients with metastatic disease and patients in the Southern Cancer Network were more likely to have chemotherapy in less than 10 weeks post-diagnosis. Over half of the advanced colorectal cancer patients who did not receive chemotherapy were aged 80+ years or had a short life expectancy. CONCLUSIONS: Although the uptake and timeliness of chemotherapy for colorectal cancer has been improving, Maori, Pacific, Asian and older patients were less likely to receive chemotherapy and less likely to receive chemotherapy in a timely manner. There is a variation in use of chemotherapy by Region with patients in the Southern Cancer region appearing to be the most likely to receive chemotherapy and to receive it within a timely period.

Prevalence of invasive cancer in a large general practice patient population in New Zealand.

INTRODUCTION The prevalence of cancer in the community is likely to be increasing due to an ageing population, implementation of cancer screening programmes and advances in cancer treatment. AIM To determine the prevalence of primary invasive cancers in a large general practice patient population in New Zealand and to characterise the health-care status of these cancer patients. METHODS Data were sourced from the patient management system of a large general practice (n=11,374 patients) in a medium-sized Waikato town and from the New Zealand Cancer Registry dataset to identify patients diagnosed with cancer between January 2009 and December 2018. RESULTS There were 206 cancer diagnoses in 201 patients; 35 cancers were diagnosed in 1887 Maori patients (1.9%) and 171 in 9487 non-Maori patients (1.8%). The age-standardised prevalence was 3092/100,000 in Maori patients and 1971/100,000 in non-Maori patients. The most prevalent cancers were breast, male genital organ, digestive organ and skin cancers. In May 2019, 81 of 201 (40.8%) patients with cancer were receiving only usual care from their general practitioner, whereas 66 (32.8%) were having their cancer managed in secondary care. Comorbidities were common, including hypertension (38.8%), gastrointestinal disorders (29.9%) and mood disorders (24.4%). DISCUSSION Results suggest that there may be disparities in cancer prevalence between Maori and non-Maori patients, although this needs to be confirmed in other general practices. Furthermore, primary care appears to be responsible for most of the care in this patient cohort and workloads should be planned accordingly, particularly with the high incidence of comorbidities.

The characteristics and outcomes of patients with colorectal cancer in New Zealand, analysed by Cancer Network.

AIM: The incidence of colorectal cancer (CRC) in New Zealand is high by international standards. Approximately 1,200 people in New Zealand die from this disease per year. Outcomes in New Zealand following a CRC diagnosis are poor. We aimed to describe the characteristics and outcomes of patients diagnosed with CRC across the four regional cancer networks in New Zealand. METHOD: Patient demographics, tumour characteristics and survival outcomes for all patients diagnosed with CRC between 2006 and 2015 were analysed retrospectively from the National Cancer Registry (NZCR) and National Mortality collection and were linked by National Health Index (NHI) number. RESULTS: A total of 29,221 CRC cases were recorded during the 10-year study period, of which the majority were cancer of the colon (67.9%). In this sample, 42.0% were >75 years, 52.1% were male and 88.1% were New Zealand European. After adjustment for factors such as age, gender, ethnicity year of diagnosis, cancer extent, cancer grade, lymph node and cancer site, cancer-related and all-cause survival were not significantly different by cancer network for those aged <75 but for patients aged >75 years, those living in the Central and Midland Cancer Network had a higher risk of dying of CRC compared to those in the Northern Cancer Network (1.12, 95% CI: 1.03-1.22 and 1.10, 95% CI: 1.02-1.18 respectively). Overall, Maori and Pacific people had worse cancer-specific and all-cause survival than New Zealand European. CONCLUSION: No regional variations were seen within New Zealand for the characteristics and survival outcomes of patients <75 diagnosed with CRC. The risk of dying from CRC increased for those >75, which is supportive of the international literature regarding outcomes for the elderly and CRC. We continue to show disparity in outcomes for Maori and Pacific patients diagnosed with CRC in New Zealand.