Malignant neoplasm of thyroid gland

This code signifies the presence of a cancerous tumor originating in the thyroid gland. This malignancy can manifest in various histological types, such as papillary, follicular, medullary, or anaplastic carcinoma, affecting the endocrine function and structure of the thyroid.

Apply this code when documentation confirms a primary malignant neoplasm of the thyroid. This includes initial diagnosis, treatment, and follow-up for the active cancer. Supporting documentation typically includes pathology reports, operative notes, and physician progress notes detailing the diagnosis.

• Always specify the exact histological type of thyroid cancer with an additional code if known and available in ICD-9-CM.
• Distinguish between primary thyroid cancer and metastatic disease to the thyroid; this code is for primary only.
• Ensure documentation clearly states "malignant" to differentiate from benign thyroid nodules or adenomas.