Extent Of Local Tumour Spread

Border: pushing/infiltrative. Lymphocytic reaction: prominent/sparse. Perineural space involvement. Solitary/multifocal, one or two lobes. Involvement of lesion capsule, extracapsular spread. Involvement of thyroid capsule, extrathyroid spread.

The TNM classification applies only to carcinomas.

pT1 tumour < 2 cm in greatest dimension, limited to thyroid pT2 2 cm < tumour < 4 cm in greatest dimension, limited to thyroid pT3 tumour >4 cm in greatest dimension, limited to thyroid or any tumour with minimal extrathyroid extension (e.g. to sternothy-roid muscles or perithyroid tissues)

pT3 > 4 cm

pT3 = minimal extrathyroidal extension pT4 = beyond thyroid capsule with invasion a: subcutaneous soft tissues, larynx, trachea, oesophagus, recurrent laryngeal nerve, or, b: prevertebral fascia, mediastinal vessels or encases carotid artery or

Figure 16.1. Thyroid carcinoma pT3 = minimal extrathyroidal extension pT4 = beyond thyroid capsule with invasion a: subcutaneous soft tissues, larynx, trachea, oesophagus, recurrent laryngeal nerve, or, b: prevertebral fascia, mediastinal vessels or encases carotid artery

Figure 16.1. Thyroid carcinoma pT4 a. tumour extends beyond capsule and involves any of: subcutaneous soft tissues, larynx, trachea, oesophagus, recurrent laryngeal nerve b. tumour invades prevertebral fascia, mediastinal vessels or encases carotid artery.

All anaplastic/undifferentiated thyroid carcinomas are pT4 (pT4a: intrathyroidal and considered surgically resectable; pT4b: extrathyroidal spread and considered surgically unresectable).

Other pathological descriptors:

(ii) grossly non-encapsulated tumour or

— pT1a, b: (a) <1 cm, (b) 1 cm < tumour < 2 cm

— pT3a, b: (a) >4cm limited to thyroid, (b) minimal extrathyroid extension.

Separate clinical stage groupings are recommended for

1. Papillary or follicular carcinoma <45 years

2. Papillary or follicular carcinoma >45 years or medullary carcinoma, and,

3. Anaplastic/undifferentiated carcinoma (all stage IV).

Note that the Royal College of Pathologists currently recommend the 5th edition TNM classification.

0 0

Post a comment