Capsular Invasion
The histopathological finding in which tumour cells breach the fibrous capsule of a salivary gland neoplasm, used as a criterion for distinguishing benign from malignant behavior.
Full Definition
Capsular invasion denotes the histological evidence of neoplastic cells penetrating through the fibrous capsule of a salivary gland tumour, and it is a critical feature assessed in the pathological evaluation of parotid, submandibular, and minor salivary gland tumours. It is one of the criteria used to classify a tumour as malignant or potentially recurrent; for example, complete capsular penetration with extension into surrounding tissue is a feature of carcinoma ex pleomorphic adenoma. Editors must distinguish 'capsular invasion' from 'capsular penetration' and 'capsule rupture' (the latter usually referring to intraoperative events). The term should not be confused with 'perineural invasion,' which describes a distinct route of tumour spread. Accurate transcription is essential as its presence or absence directly affects pathological staging.
Usage
Usage note: Capsular invasion and capsule rupture are not interchangeable. Confirm the correct term with the original dictation or report before editing.
In Context
- "Capsular invasion extending beyond the tumour capsule into the surrounding parotid parenchyma was identified on permanent section." — Surgical pathology report
- "Editors must not substitute 'capsular rupture' for 'capsular invasion'; the former is an intraoperative complication, the latter a histopathological finding." — Report editing protocol