Clinical and histologic factors associated with melanoma thickness in New Zealand Europeans, Maori, and Pacific peoples

Comparison of Cancer Mortality and Incidence Between New Zealand and Australia and Reflection on Differences in Cancer Care: An Ecological Cross-Sectional Study of 2014-2018

BACKGROUND

Despite many background similarities, New Zealand showed excess cancer deaths compared to Australia in previous studies. This study extends this comparison using the most recent data of 2014-2018.

METHODS

This study used publicly available cancer mortality and incidence data of New Zealand Ministry of Health and Australian Institute of Health and Welfare, and resident population data of Statistics New Zealand. Australian cancer mortality and incidence rates were applied to New Zealand population, by site of cancer, year, age and sex, to estimate the expected numbers, which were compared with the New Zealand observed numbers.

RESULTS

For total cancers in 2014-2018, New Zealand had 780 excess deaths in women (17.1% of the annual total 4549; 95% confidence interval (CI) 15.8-18.4%), and 281 excess deaths in men (5.5% of the annual total 5105; 95% CI 4.3-6.7%) compared to Australia. The excess was contributed by many major cancers including colorectal, melanoma, and stomach cancer in both sexes; lung, uterine, and breast cancer in women, and prostate cancer in men. New Zealand's total cancer incidences were lower than those expected from Australia's in both women and men: average annual difference of 419 cases (-3.6% of the annual total 11 505; 95% CI -4.5 to -2.8%), and 1485 (-11.7% of the annual total 12 669; 95% CI -12.5 to -10.9%), respectively. Comparing time periods, the excesses in total cancer deaths in women were 15.1% in 2000-07, and 17.5% in 1996-1997; and in men 4.7% in 2000-2007 and 5.6% in 1996-1997. The differences by time period were non-significant.

CONCLUSION

Excess mortality from all cancers combined and several common cancers in New Zealand, compared to Australia, persisted in 2014-2018, being similar to excesses in 2000-2007 and 1996-1997. It cannot be explained by differences in incidence, but may be attributable to various aspects of health systems governance and performance.

Epidemiological trends in the diagnosis of melanoma in a Southern European population: analysis of a large database from a tertiary referral center

The aim of this study was to present the epidemiological, clinicopathological, and treatment characteristics of patients diagnosed and treated in a tertiary referral center and to analyze independent factors associated with these characteristics. In this cohort study, epidemiological, clinicopathological, and treatment characteristics of 1461 consecutive melanoma patients diagnosed and treated in a tertiary referral center in 1987-2015 were prospectively collected in a registry. All patients underwent resection of their melanoma lesion. Multiple logistic regression analysis was used to examine independent correlations between characteristics. Internal validation of these correlations was performed by the bootstrap method. The median age of the patients was 53 years. Female sex had a slight predominance, whereas the majority were of Southern European origin. Superficial spreading melanoma was associated with younger age (P<0.001), whereas the nodular melanoma histological subtype was associated independently with indoor occupation (P=0.021) and diagnosis in the years 2004-2015 (P=0.002). Melanomas with Breslow thickness above 1.0 mm were associated with skin type III-IV (P=0.021) and diagnosis in the years 1987-2003 (P=0.046). In addition, histological ulceration was associated with older age (P=0.004) and diagnosis in the years 1987-2003 (P<0.001), whereas histological regression was associated independently with older age (P=0.001). This study presented independent associations between epidemiological, histopathological, and treatment characteristics, which might help to better understand melanoma disease and treatment practices in Southern Europe.

Successful melanoma triage by a virtual lesion clinic (teledermatoscopy)

BACKGROUND

A Virtual Lesion Clinic (VLC) using teledermatoscopy was established to improve efficiency of the melanoma referral pathway.

OBJECTIVES

To assess diagnostic accuracy and to compare wait-times and costs of VLC and conventional clinics.

METHODS

Patients with suspected melanoma referred from primary care into a publicly funded health system attended local skin imaging centres, rather than hospital outpatient clinics. A teledermatologist assessed each lesion choosing specialist assessment/excision, General Practitioner (GP) follow-up, to re-image in 3 months, or self-monitoring/no concern.

RESULTS

613 skin lesions in 310 patients were evaluated over 12 months. Median time between receipt of referral and attendance at the VLC was 9 days compared to 26.5 days for standard outpatient assessment. Sixty-six percent (404/613) of lesions were considered benign, and 12% (73/613) were suspicious for melanoma. Of 129 lesions excised, 98 were skin cancers including 48 histologically confirmed melanomas with one spitzoid tumour of unknown malignant potential (STUMP), i.e. one melanoma per 1.59 suspected lesions biopsied and one melanoma in every 12.8 referred to the service. There were 49 non-melanoma skin cancers (NMSC). Teledermatoscopic diagnosis of melanomas was found to have a positive predictive value (PPV) of 63%. Compared to the conventional clinic, cost reductions from running the VLC for 1 year were in excess of NZ$364,000 (or NZ$1174/patient seen).

CONCLUSIONS

The VLC offered an efficient, accurate and cost effective way of processing suspected melanoma referrals to the public health system.

Individual risk of cutaneous melanoma in New Zealand: developing a clinical prediction aid

Background

New Zealand and Australia have the highest melanoma incidence rates worldwide. In New Zealand, both the incidence and thickness have been increasing. Clinical decisions require accurate risk prediction but a simple list of genetic, phenotypic and behavioural risk factors is inadequate to estimate individual risk as the risk factors for melanoma have complex interactions. In order to offer tailored clinical management strategies, we developed a New Zealand prediction model to estimate individual 5-year absolute risk of melanoma.

Methods

A population-based case–control study (368 cases and 270 controls) of melanoma risk factors provided estimates of relative risks for fair-skinned New Zealanders aged 20–79 years. Model selection techniques and multivariate logistic regression were used to determine the important predictors. The relative risks for predictors were combined with baseline melanoma incidence rates and non-melanoma mortality rates to calculate individual probabilities of developing melanoma within 5 years.

Results

For women, the best model included skin colour, number of moles > =5 mm on the right arm, having a 1st degree relative with large moles, and a personal history of non-melanoma skin cancer (NMSC). The model correctly classified 68% of participants; the C-statistic was 0.74. For men, the best model included age, place of occupation up to age 18 years, number of moles > =5 mm on the right arm, birthplace, and a history of NMSC. The model correctly classified 67% of cases; the C-statistic was 0.71.

Conclusions

We have developed the first New Zealand risk prediction model that calculates individual absolute 5-year risk of melanoma. This model will aid physicians to identify individuals at high risk, allowing them to individually target surveillance and other management strategies, and thereby reduce the high melanoma burden in New Zealand.

A comparison of trends in melanoma mortality in New Zealand and Australia: the two countries with the highest melanoma incidence and mortality in the world

Background

New Zealand and Australia have the highest incidence and mortality rates from cutaneous melanoma in the world. The predominantly fair-skinned New Zealanders and Australians both enjoy sun, tanned skin and the outdoors, and differences in these activities among generations have been important determinants of trends in melanoma mortality.

We examined whether New Zealand trends in melanoma mortality mirror those in Australia, through detailed comparison of the trends in both countries from 1968 to 2007.

Methods

Five-year age-specific and age-standardised mortality rates were calculated for each country for 5-year time periods. Tests for trends in age-specific rates were performed using the Mantel-Haenszel extension chi-square test. The age-adjusted mortality rate ratios for New Zealand/Australia were plotted against period of death to show relative changes in mortality over time. Age-specific mortality rates were plotted against period and the median year of birth to illustrate age-group and birth cohort effects. To compare the mortality of birth cohorts, age-adjusted melanoma mortality rate ratios were calculated for the birth cohorts in the quin-quennial tables of mortality rates.

Results

The age-standardised mortality rate for melanoma increased in both sexes in New Zealand and Australia from 1968 to 2007, but the increase was greater in New Zealanders and women in particular. There was evidence of recent significant decreases in mortality in younger Australians and less so in New Zealand women aged under 45 years. Mortality from melanoma increased in successive generations born from about 1893 to 1918. In Australia, a decline in mortality started for generations born from about 1958 but in New Zealand there is possibly a decrease only in generations born since 1968.

Conclusions

Mortality trends in New Zealand and Australia are discrepant. It is too early to know if the pattern in mortality rates in New Zealand is simply a delayed response to melanoma control activities compared with Australia, whereby we can expect the same downward trend in similar age groups in the next few years. Specific research is needed to better understand and control the increases in mortality and thickness of melanoma in New Zealand.

Epidemiological profile of patients with cutaneous melanoma in a region of southern Brazil

Cutaneous melanoma (CM) is responsible for 75% of deaths from malignant skin cancer. The incidence of CM in the southern region of Brazil, particularly in the western region of Santa Catarina, is possibly higher than estimated. In this study, the clinical and epidemiological profile of patients with CM treated in the western region of Santa Catarina was examined. A cross-sectional study was performed with patients diagnosed with CM from January 2002 to December 2009, from 78 counties of the western region of the state of Santa Catarina. Data were collected using a protocol adapted from the Brazilian Melanoma Group and 503 patients were evaluated. The incidence and prevalence of CM found in this region are much higher than those found elsewhere in the country. This fact is most likely due to the phenotypic characteristics of the population and the high incidence of UV radiation in this region due to its location in southern Brazil, as is the case in the countries of Oceania.