TIDBITS

WHO (World Health Organization) classified it under thyroid tumors, as per Revised WHO classification of thyroid tumours (1988)* (11)

Table. 2 Diagnostic/ Histogenetic classification of thyroid tumors

B. Malignant tumors

IV. Tumors showing thymic or related branchial pouch differentiation

1. Ectopic thymoma

2. Spindle cell epithelial tumour with thymic-like differentiation SETTLE

3. Carcinoma showing thymus like differentiation CASTLE

 

Classified by ICD-0-3 (International Classification of Diseases for Onocology) as a tumor of the thymus 1999 (12)

Neck Tumors of Thymic or Related Branchial Pouch Derivation

8587/0 Ectopic hamartomatous thymoma

8580/1 Ectopic cervical thymoma

8588/3 Spindle epithelial tumor with thymus-like element

Spindle epithelial tumor with thymus-like differentiation

SETTLE

8589/3 Carcinoma showing thymus-like element

Carcinoma showing thymus-like differentiation

CASTLE