SST and neoplasm: SST and CXCR4 expression has also been evaluated in thyroid carcinomas, but with contradictory results regarding both the extent of their expression and their correlations with clinical data such as tumour size or stage or patient outcomes (an overview of studies on SST and CXCR4 expression in thyroid carcinomas during the past 20 years is given in Tables 1 and 2).