AXIN1 and neoplasm: The malignant struma ovarii and adjacent benign teratoma also presented cytoplasmic β-catenin expression, and, interestingly, loss of heterozygosity (LOH), a common genetic event in cancer development, known to be involved in the somatic inactivation of wild-type alleles from tumour suppressor genes, was observed, in the AXIN1 gene, in the ectopic tissues from this patient (Figure S1A).