Effect of pregnancy and lactation on a benign phyllodes tumour

Phyllodes tumours occurring in pregnancy are very rare. While most cases presented as rapidly enlarging masses, we present a benign phyllodes tumour which had the most growth in the first half of pregnancy followed by gradual growth in the latter half of pregnancy and lactation, as characterised on ultrasound imaging. This is the first report, to the best of our knowledge, which has objective measurements of the lesion before, during and after pregnancy. It also highlighted the need for a vigilant approach to fibroepithelial lesions in pregnancy, instead of attributing the growth of these lesions solely to hormonal changes.