Treatment modalities for Māori and New Zealand European men with localised prostate cancer

Equity of travel required to access first definitive surgery for liver or stomach cancer in New Zealand

In New Zealand, there are known disparities between the Indigenous Māori and the majority non-Indigenous European populations in access to cancer treatment, with resulting disparities in cancer survival. There is international evidence of ethnic disparities in the distance travelled to access cancer treatment; and as such, the aim of this paper was to examine the distance and time travelled to access surgical care between Māori and European liver and stomach cancer patients. We used national-level data and Geographic Information Systems (GIS) analysis to describe the distance travelled by patients to receive their first primary surgery for liver or stomach cancer, as well as the estimated time to travel this distance by road, and the surgical volume of hospitals performing these procedures. All cases of liver (ICD-10-AM 3rd edition code: C22) and stomach (C16) cancer that occurred in New Zealand (2007–2019) were drawn from the New Zealand Cancer Registry (liver cancer: 866 Māori, 2,460 European; stomach cancer: 953 Māori, 3,192 European), and linked to national inpatient hospitalisation records to examine access to surgery. We found that Māori on average travel 120km for liver cancer surgery, compared to around 60km for Europeans, while a substantial minority of both Māori and European liver cancer patients must travel more than 200km for their first primary liver surgery, and this situation appears worse for Māori (36% vs 29%; adj. OR 1.48, 95% CI 1.09–2.01). No such disparities were observed for stomach cancer. This contrast between cancers is likely driven by the centralisation of liver cancer surgery relative to stomach cancer. In order to support Māori to access liver cancer care, we recommend that additional support is provided to Māori patients (including prospective financial support), and that efforts are made to remotely provide those clinical services that can be decentralised.

Prostate cancer outcomes disparities: Population survival analysis in an ethnically diverse nation

BACKGROUND

Prostate cancer represents a significant health burden on New Zealand men. There are increasing concerns regarding inequities in prostate cancer morbidity and mortality among the different ethnic groups in New Zealand. This study aims to assess ethnic differences in survival outcomes among men newly diagnosed with prostate cancer.

MATERIALS AND METHODS

The analyzed cohort included 42,563 men, 40 years or older, diagnosed with prostate cancer from January 1st, 2000 to January 1st, 2016. Overall and cancer-specific survivals were estimated for the main ethnic groups in New Zealand namely: Māori (indigenous), Pacific, Asian, and European. Hazard ratio (HR) of death from prostate cancer was calculated with Fine-Gray competing risk regression, while adjusting for age, socioeconomic deprivation, year of cancer diagnosis, residential status, presence of urology service, and cancer grade at diagnosis.

RESULTS

Among all ethnic groups, Māori participants consistently had worst survival outcomes. At 15-year follow-up, the overall cumulative survival probabilities were 39.8%, 43.6%, 63.3%, and 46.5%, for Māori, Pacific, Asian and European men, respectively. In the same order, cancer-specific survivals were 62.7%, 64.3%, 79.8% and 72.0%. Māori men had 43% higher risk of dying from prostate cancer when compared to Europeans. This persisted following adjustments in the multivariable model (adjusted HR = 1.44, [95% CI: 1.29-1.61], P< 0.001). Conversely, differences in sociodemographic and cancer characteristics between Pacific and European men could explain the higher mortality risk in the former group (adjusted HR = 1.00, [95% CI: 0.84-1.19], P= 0.990).

CONCLUSIONS

Significant ethnic disparities in prostate cancer survival outcomes are currently present in New Zealand. Several explanations have been proposed to account for this observation including differences in comorbidities, healthcare access and cancer grade at diagnosis.

Comparing cancer incidence, stage at diagnosis and outcomes of First Nations and all other Manitobans: a retrospective analysis

Background

Globally, epidemiological evidence suggests cancer incidence and outcomes among Indigenous peoples are a growing concern. Although historically cancer among First Nations (FN) peoples in Canada was relatively unknown, recent epidemiological evidence reveals a widening of cancer related disparities. However evidence at the population level is limited. The aim of this study was to explore cancer incidence, stage at diagnosis, and outcomes among status FN peoples in comparison with all other Manitobans (AOM).

Methods

All cancers diagnosed between April 1, 2004 and March 31, 2011 were linked with the Indian Registry System and five provincial healthcare databases to compare differences in characteristics, cancer incidence, and stage at diagnosis and mortality of the FN and AOM cohorts. Cox proportional hazard regression models were used to examine mortality.

Results

The FN cohort was significantly younger, with higher comorbidities than AOM. A higher proportion of FN people were diagnosed with cancer at stages III (18.7% vs. 15.4%) and IV (22.4% vs. 19.9%). Cancer incidence was significantly lower in the FN cohort, however, there were no significant differences between the two cohorts after adjusting for age, sex, income and area of residence. No significant trends in cancer incidence were identified in either cohort over time. Mortality was generally higher in the FN cohort.

Conclusions

Despite similar cancer incidence, FN peoples in Manitoba experience poorer survival. The underlying causes of these disparities are not yet understood, particularly in relation to the impact of colonization and other determinants of health.

Cancer treatment and the risk of cancer death among Aboriginal and non-Aboriginal South Australians: analysis of a matched cohort study

BACKGROUND

Aboriginal and Torres Strait Islander Australians have poorer cancer outcomes than other Australians. Comparatively little is known of the type and amount of cancer treatment provided to Aboriginal and Torres Strait Islander people and the consequences for cancer survival. This study quantifies the influence of surgical, systemic and radiotherapy treatment on risk of cancer death among matched cohorts of cancer cases and, the comparative exposure of cohorts to these treatments.

METHODS

Cancers registered among Aboriginal South Australians in 1990-2010 (N = 777) were matched with randomly selected non-Indigenous cases by sex, birth and diagnostic year, and primary site, then linked to administrative cancer treatment for the period from 2 months before to 13 months after diagnosis. Competing risk regression summarised associations of Indigenous status, geographic remoteness, comorbidities, cancer stage and treatment exposure with risk of cancer death.

RESULTS

Fewer Aboriginal cases had localised disease at diagnosis (37.2% versus 50.2%) and they were less likely to: experience hospitalisation with cancer diagnosis, unadjusted odds ratio (UOR) = 0.76; 95%CI = 0.59-0.98; have surgery UOR = 0.65; 95%CI = 0.53-0.80; systemic therapies UOR = 0.64; 95%CI = 0.52-0.78; or radiotherapy, UOR = 0.76; 95%CI = 0.63-0.94. Localised disease carried lower risk of cancer death compared to advanced cases receiving surgery or systemic therapies, SHR = 0.34; 95%CI = 0.25-0.47 and SHR = 0.35; 95%CI = 0.25-0.48. Advanced disease and no treatment carried higher risk of cancer death, SHR = 1.82; 95%CI = 1.26-2.63.

CONCLUSION

The effects of treatment did not differ between Aboriginal and non-Indigenous cohorts. However, comparatively less exposure to surgical and systemic treatments among Aboriginal cancer cases further complicated the disadvantages associated with geographic remoteness, advanced stage of disease and co-morbid conditions at diagnosis and add to disparities in cancer death. System level responses to improving access, utilisation and quality of effective treatments are needed to improve survival after cancer diagnosis.

Systematic review of disparities in surgical care for Māori in New Zealand

BACKGROUND

Health equity for Indigenous peoples in the context of surgery has recently become topical amongst surgeons in Australasia. Health inequities are amongst the most consistent and compelling disparities between Māori and New Zealand Europeans (NZE) in New Zealand (NZ). We aimed to investigate where ethnic disparities in surgical care may occur and highlight some of the potential contributing factors, over all surgical specialties, between Māori and NZE adults in NZ.

METHODS

A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A series of electronic searches were performed in Medline, Embase, PubMed and CINAHL.

RESULTS

Ten studies met the inclusion criteria. All studies employed a range of indicators for surgical care including receipt of surgery following diagnosis, delays to treatment and post-operative morbidity and mortality. Disparities in the receipt of surgical treatment for several cancers were observed for Māori and remained after adjustment for socioeconomic variables and extent of disease. Māori were more likely to experience delays in treatment and referral to other medical specialties involved in their care.

CONCLUSION

Despite the significant variation in the types of diseases, procedures and indicators of surgical care of the included studies, consistent findings are that disparities in different aspects of surgical care exist between Māori and NZE in NZ. This review highlights the need to better quantify the important issue of health equity for Māori in surgery given the lack of studies over the majority of surgical specialties.

The cost-effectiveness of active surveillance compared to watchful waiting and radical prostatectomy for low risk localised prostate cancer

Background

Radical prostatectomy is the most common treatment for localised prostate cancer in New Zealand. Active surveillance was introduced to prevent overtreatment and reduce costs while preserving the option of radical prostatectomy. This study aims to evaluate the cost-effectiveness of active surveillance compared to watchful waiting and radical prostatectomy.

Methods

Markov models were constructed to estimate the life-time cost-effectiveness of active surveillance compared to watchful waiting and radical prostatectomy for low risk localised prostate cancer patients aged 45–70 years, using national datasets in New Zealand and published studies including the SPCG-4 study. This study was from the perspective of the Ministry of Health in New Zealand.

Results

Radical prostatectomy is less costly than active surveillance in men aged 45–55 years with low risk localised prostate cancer, but more costly for men aged 60–70 years. Scenario analyses demonstrated significant uncertainty as to the most cost-effective option in all age groups because of the unavailability of good quality of life data for men under active surveillance. Uncertainties around the likelihood of having radical prostatectomy when managed with active surveillance also affect the cost-effectiveness of active surveillance against radical prostatectomy.

Conclusions

Active surveillance is less likely to be cost-effective compared to radical prostatectomy for younger men diagnosed with low risk localised prostate cancer. The cost-effectiveness of active surveillance compared to radical prostatectomy is critically dependent on the ‘trigger’ for radical prostatectomy and the quality of life in men on active surveillance. Research on the latter would be beneficial.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3522-z) contains supplementary material, which is available to authorized users.