Parathyroid Gland Involvement by Thyroid Cancer: Results from a Large Series of Thyroidectomies Performed in Two Italian University Hospitals and Review of the Literature

Figure 3

Patterns of parathyroid involvement by thyroid cancer. Pattern A: direct invasion by infiltrative growth from the primary thyroid neoplasm; Pattern B: extension of thyroid malignancy into the gland, from which cancer nests are separated by an intervening fibrous capsule (pseudocapsule); Pattern C: true metastasis within the gland, with no evidence of continuity from the primary thyroid tumour.