Melanoma in Tasmania, Australia: 1981 to 2016

Rapid Communication

Ann Hematol Oncol. 2019; 6(10): 1272.

Melanoma in Tasmania, Australia: 1981 to 2016

D Czarnecki*

Doctor’s Care Network, Australia

*Corresponding author: D Czarnecki, Doctor’s Care Network, 157 Scoresby Rd, Boronia, 3155, Australia

Received: September 17, 2019; Accepted: November 19, 2019; Published: November 26, 2019

Abstract

Introduction: There is controversy as to whether or not the incidence of melanoma is decreasing in the Australian population because the racial composition of the Australian population is changing at a rapid rate with many people at low risk for the disease settling in Australia. Not many immigrants settle in the island state of Tasmania and the population is overwhelmingly of European ancestry. In this article the incidence of melanoma in Tasmanians is calculated for the Census years between 1981 and 2016.

Materials and Methods: Data on the number of invasive melanomas was obtained from the State Cancer Registry. Data on the Tasmanian population were obtained from the Australian Bureau of Statistics.

Results: Between 1981 and 2016 the number of invasive melanomas removed from was susceptible. Tasmanians increased almost five-fold. The population increased by 23%. In 1981, 99% of the population was susceptible to melanoma. In 2016, 96% was susceptible. The Age Standardized Rate (ASR) of melanoma increased by almost three fold while the Crude Rate (CR) increased by almost four fold.

Conclusion: In the most homogeneous population of Australians, the incidence of melanoma is continuing to increase despite public health campaigns running over the entire study period. In a homogeneous population, ASR and CR for melanoma show similar trends. In a changing population with a large number of people not susceptible to melanoma, ASR cannot be used to determine trends.

Introduction

The number of invasive melanomas removed from Australians has quadrupled between 1982, when data were first recorded, and 2016 [1]. Over the same time the population increased by 65% [2]. Despite the rate of increase in melanomas being far greater than the rate of population increase, the Age Standardized Rate (ASR) of melanomas has stabilized since 2001 [1]. Australian authors have claimed that the stabilization in the ASR is attributed to public health campaigns that have being running since 1980 and that the incidence of melanoma is now decreasing in young Australians [3]. The authors failed to mention that the Australian population has greatly changed since 1981 with a large number of dark skinned people, at low risk for melanoma, settling in Australia. If adjustments are made for the population change, and the incidence is calculated for the susceptible population, the incidence has not stabilized but is increasing by 2% a year [4].

The magnitude of the change can be seen by the great increase in the number of people born in Asia who were living in Australia. In the 1981 Census, 1.7% of Australians were born in Asia but this had increased to 10.4% in the 2016 Census [2]. Such a big increase in people at low risk for the disease must lower the incidence of melanoma in the entire population. If immigration had no influence on the incidence of melanoma but public health campaigns had been beneficial, the incidence of melanoma should be decreasing in an area that has had a slight change in its racial composition. The island state of Tasmania is the one such area in Australia. Tasmania is the most southern Australian state and lies in the temperate zone of Australia between 41° and 44° south. The majority of the population lives at 43° south (Table 1).

Citation: D Czarnecki. Melanoma in Tasmania, Australia: 1981 to 2016. Ann Hematol Oncol. 2019; 6(10): 1272.