TPO and thyroiditis: Many studies have described immunohistochemical markers that improve the diagnosis of thyroid conditions such as TPO on their own or, alternatively, associated with other markers such as galectine-3, CK19, HBME-1, etc. De Micco determined that anti-TPO antibody MoAb47 recognized TPO expression in normal and benign thyroid tissues, but only in 3 % of malignant tumors [7].