Certain high-risk features are markers of an aggressive basal cell carcinoma (BCC). These features are related to the location, size, and pathologic features of the tumour as well as certain characteristics of the patient.


High-Risk Features of the Tumour

Large size: Size greater than 20 mm (2 cm or about 0.8 inch, the diameter of a nickel). This designation applies to tumours on the trunk and extremities

Problematic location:

  • On sensitive/mucosal locations (such as the genitals) as well as areas that tend to have lots of sun exposure, such as the central face, eyelids, eyebrows, on or around the nose, lips, chin, jaw, temple, and ear (the mask area), hands, and feet
  • On a site that has been previously treated with radiotherapy

Certain symptoms: Causing pain and itchiness (which may indicate neurologic involvement)

Certain tumor subtypes: Ones that have an aggressive growth pattern, which is specific information that should be noted on the pathology report

A tumor that has come back (recurred)


High-Risk Features of the Patient

Immunosuppression: resulting from the immunosuppressive regimens used after organ transplantation, infection with the human immunodeficiency virus (HIV), or certain blood cancers

The greater number of high-risk features, the more likely you are to have the BCC come back. To see how risk features are integrated into the staging of of BCC, see STAGING OF BCC: A PRACTICAL DESCRIPTION.

Examples of High-Risk Features

Below are images that illustrate some of the high-risk features described in the section High-Risk Features of The Tumour.

This tumour’s large size (greater than 20 mm in diameter) makes it high risk



A representation of the mask area. Tumours that arise in this area are high risk.


A high-risk BCC on the nose (part of the mask region)


A large, high-risk lesion on the cheek

Watermarked images courtesy of DermNetNZ,org. For more information, see