Exploring correlations between the breast density of the women of Papua New Guinea and breast cancer risk factors.

INTRODUCTION

Papua New Guinea (PNG), has experienced an increase in breast cancer incidence correlating to the westernisation of the country. Increased breast density is known to increase breast cancer risk. This study investigates if there are any factors unique to the women of PNG that may impact breast density and breast cancer risk.

METHOD: A survey was undertaken of 1,161 women who had undergone mammographic imaging at the Pacific International Hospital (PIH). Results were correlated with the five Tabár mammographic parenchymal patterns (TP), recorded for each woman and geographical location, parity, breast size, occupation, marital and menstrual status, smoking and alcohol consumption, hormone replacement therapy (HRT), and exercise. Statistical analysis was undertaken using chi-square test, Fisher's exact test and Odds Ratio (OR).

RESULTS

Relationships were identified between TP and parity (p < 0.001), marital status (p < 0.001), smoking (p < 0.001), alcohol intake (p = 0.029) and HRT (p = 0.029). There was no evidence of a relationship between pattern type and geographical location (p = 0.290), breast size (p = 0.592), occupation (p = 0.724), menstruation (p = 0.866) or exercise (p = 0.290). Married women, OR = 0.4004, CI 95% (0.2873-0.5579) and those with higher parity, OR 0.5034, CI 95% (0.3693-0.6862) were half as likely to have increased breast density reducing risk.

CONCLUSION

There was no clear relationship across almost all data. Factors associated with increased breast density in PNG included parity, marital status, smoking, alcohol, and HRT use were evidenced in this snapshot of PNG women. Breast cancer risk was shown to be reduced for married women and those with increased parity.