Basal cell carcinoma: mixed (syn. multicomponent or multifocal)

LAST UPDATED: Jan 19, 2026

Patient Information Leaflet
Link: Basal cell carcinoma

https://www.pcds.org.uk/patient-info-leaflets/basal-cell-carcinoma

Introduction

A mixed basal cell carcinoma (BCC) is a BCC with more than one histological subtype.

This chapter is set out as follows:

Aetiology
Clinical findings
Images
Management

Aetiology

Up to one-third of all BCC have mixed histological features
Evidence suggests that mixed BCC originate from one single focus (monoclonal) rather than multiple independent sites, despite their often disconnected histological appearance; the term 'multifocal BCC' should be abandoned. It is likely that as this group of BCC evolve there is phenotypic transformation of the malignant cells

Clinical findings

May be poorly defined due to the presence of different subtypes of BCC and the fact that more aggressive histological features, such as infiltrative pattens, are common in such lesions

Clinical Images

Please refer to notes on image rights at bottom of the page with regards to individual image ownership.

Management

The lesion should be managed in line with which of the described histological subtypes is the most aggressive, for example, a lesion showing both nodular and infiltrative components should be managed as an infiltrative BCC
For more information refer to the related chapter Basal cell carcinoma - an overview

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Image Rights - The PCDS would like to thank Dermatoweb, DermQuest (Galderma), and others who have contributed images. All named individuals and organisations maintain copyright for the relevant images.