Cutaneous adnexal tumours

In development

Overview

Cutaneous adnexal, or appendageal, tumours comprise a range of benign and malignant tumours that show differentiation towards the adnexal structures found in normal skin. They may display more than one type of differentiation but they are typically classified by the dominant component.

They include the following.

Apocrine and eccrine differentiation

Benign eg poroma, cylindroma

Malignant eg porocarcinoma, digital papillary adenocarcinoma

Follicular differentiation

Benign eg pilomatrixoma

Malignant eg pilomatrical carcinoma, trichilemmal carcinoma

Sebaceous differentiation

Benign eg sebaceous adenoma

Malignant: sebaceous carcinoma

Other special sites

Mammary Paget disease

Extramammary Paget diease

Hidradenoma papilliferum

Pathology

1. Pathology departments will adhere to guidelines on specimen handling and reporting as described in the Royal College of Pathology Minimum Data Set (MDS) for adnexal carcinomas.

2. RSH clinicians are encouraged to use a dedicated form for submission of samples to histopathology.

Sebaceous adenoma

Tumours should be tested for mismatch repair syndrome with an initial immunohistochemistry screen for mutant MLH1, MSH2, MSH6, PMS2. If any are detected then the patient should be referred to the SW London Regional Genetics Service for full assessment for potential Muir Torre syndrome.