You cannot have lung cancer in the liver. She might have mean't she originally had it found first in the lung which then followed in the liver.
Cancer adores sugar, when it does not get enough it starts the body producing high levels of latic acid in order for the liver to convert it to glucose again. This is why Vitamin C (Ascorbic Acid and Sodium Ascorbate) work so well again cancer and tumours. Vitamin C not only oxidises the tumour on the outside but its one of only a handful of things which can get inside a Tumour other than Cesium etc.