MONDO_0006466 (thyroid gland spindle cell tumor with thymus-like differentiation) is a rare, slow growing, primary carcinoma of the thyroid gland characterized by a lobulated architectural pattern and the presence of a biphasic cellular population composed of spindle epithelial cells and glandular cells. A small number of cases are composed exclusively of spindle epithelial cells or glandular cells. Also known as: SETTLE, settle, settle tumor, settle tumour, spindle epithelial tumor with thymus-like differentiation tumor, spindle epithelial tumour with thymus-like differentiation tumour.