Undifferentiated carcinoma of thyroid gland

Description

A primary carcinoma of the thyroid gland composed of undifferentiated cells. The malignant cells demonstrate evidence of epithelial differentiation, either by immunohistochemistry or electron microscopic studies. Microscopically, in the majority of cases there is a mixture of spindle, epithelioid, and giant cells. The vast majority of the patients present with a rapidly enlarging neck mass. The clinical course is invariably aggressive.

Coding note from above levels

For use of this category, reference should be made to the mortality coding rules and guidelines in the Reference Guide.

Inclusions

• anaplastic carcinoma of thyroid gland

Exclusions from above levels

• http://id.who.int/icd/entity/1965082709 – Malignant mesenchymal neoplasms
• http://id.who.int/icd/entity/879154182 – Neoplasms of central nervous system or related structures
• http://id.who.int/icd/entity/944754984 – Neoplasms of haematopoietic or lymphoid tissues