Mixed papillary-follicular carcinoma of the thyroid is included under the category of the papillary carcinoma of the thyroid. The characteristic feature is the papilla - the finger-like projections of cells that are the proliferation of follicular cells. Note the large papilla in this slide. Papillary carcinoma of the thyroid is the most common form of thyroid cancer in both the child and in the adult. Even with metastases, the 10 year survival rate is about 75%.