Basal cell carcinoma | Mate pukupuku kiritai

Also known as rodent ulcers

Overview
Clinicians
Clinicians

Basal cell carcinomas (mate pukupuku kiritai) are the most common and the least serious form of skin cancer – as long as they are treated.

On this page, you can find the following information:

What is basal cell carcinoma?
What causes basal cell carcinomas?
Who is most at risk of developing a basal cell carcinoma?
Where do basal cell carcinomas appear?
What do basal cell carcinomas look like?
What should I do if I think I have a basal cell carcinoma?
How are basal cell carcinomas treated?
How can I prevent basal cell carcinoma from recurring?

Key points about basal cell carcinoma

Basal cell carcinomas are a type of non-melanoma skin cancer.
They often appear as a pale, pink or pearly smooth lump.
Although more common among older people, they can develop in people in their early 40s or even younger.
Most basal cell carcinomas are caused by long-term exposure to ultraviolet (UV) radiation from sunlight, so almost all occur on parts of your body that get the most sun.
They tend to be slow growing and very rarely spread to other parts of your body. Therefore they are almost never a danger to life.

What is basal cell carcinoma?

Basal cell carcinomas (BCC) occur when a mutation develops in one of your skin's basal cells. Basal cells are found at the bottom of the epidermis –the outermost layer of your skin. Basal cells produce new skin cells as old ones near the surface die off. Sun exposure is the main cause of damage leading to BCC. As a result, almost all BCCs occur on parts of your body that get the most sun.

Image source DermNet, NZ. Also see more images of basal cell carcinoma at DermNet NZ.

What causes basal cell carcinomas?

The main cause of damage leading to BCC is sun exposure. This is usually a combination of:

long-term, everyday sun exposure, and
occasional intense exposure, usually leading to sunburn.

In some cases, they are the result of damage caused by things such as burns, scars, infections, vaccinations or tattoos.

Who is most at risk of developing a basal cell carcinoma?

You are at highest risk of developing a BCC if you:

are older
have pale skin and burn easily
have spent a lot of time outdoors for work or leisure
live in a sunny climate
use sunbeds or sunbathe
have previously had a basal cell carcinoma or another type of skin cancer
have a condition or take medicines that affect your immune system (immune suppression).

Where do basal cell carcinomas appear?

Almost all BCCs occur on parts of your body that get the most sun, such as your face, ears, neck, scalp, shoulders and back. They occur less often on other parts of your body or legs. In rare cases, they can appear on parts of your body that are normally protected from the sun.

What do basal cell carcinomas look like?

BCCs often appear as a change in your skin, such as a lump or a sore that does not heal.

The main features are:

slow growing – months to years
a pearly white, skin-coloured or pink bump that is translucent (you can see a bit through the surface)
waxy, small, raised lesions that may have a dent in the centre
brown or blue-black areas, in some cases
a scaly red flat mark on the skin, in some cases
a tendency to bleed or turn into an ulcer
scaly, oozing or crusted areas
varying in size from a few millimetres to several centimetres in diameter.

What should I do if I think I have a basal cell carcinoma?

If you notice a change to or growth on your skin, make an appointment to see your doctor straight away. Your doctor will assess the size, location and look of the growth. They will also ask you how long you have had it, whether it bleeds or itches, etc.

If your doctor thinks the growth may be cancer, they may take a small sample of tissue (a biopsy). The tissue sample will be sent to a laboratory and examined under a microscope. Your doctor will let you know whether the sample showed any cancer cells, and will recommend appropriate treatment if necessary.

How are basal cell carcinomas treated?

Treatment of basal cell carcinoma depends on its type, size and location and other factors, such as your preference.

Options include:

surgical removal of the cancer (this is the most common treatment method)
freezing it with liquid nitrogen
topical therapies (creams)
radiotherapy
photodynamic therapy (a specialist treatment using light to activate creams).

If you have a BCC, talk with your doctor about which treatment option is best for you. Treatment will almost always cure a BCC, provided it is found at an early stage. Your doctor may want to plan a future appointment to check for recurrences, new skin cancers or precancerous changes.

How can I prevent basal cell carcinoma from recurring?

Most basal cell carcinomas can be treated and cured. However, it is possible for these types of cancers to recur or for new skin cancers to appear.

Do the following to reduce the risk of new cancers occurring:

Keep all follow-up appointments with your GP or skin specialist.
Regularly check all your skin (from head to toe). If you see anything that is growing, bleeding or in any way changing, go and see your doctor straight away. See skin checks
Protect your skin from the sun and avoid indoor tanning. This is essential to prevent further damage, which will increase the risk of getting another skin cancer.

Ways to protect your skin

Avoid outdoor activities when the sun is strongest – between 10 am and 4 pm from September to April in New Zealand.
Wear sunscreen and lip balm daily that offer SPF 30 or higher sun protection.
Use sunscreen that offers broad-spectrum (UVA/UVB) protection and is water resistant.
Apply the sunscreen and lip balm to dry skin 15 minutes before going outdoors.
Apply the sunscreen to every part of your body that will not be covered by clothing. Reapply it every two hours if you are swimming or sweating.
Whenever possible, wear a wide-brimmed hat, long sleeves and long pants.
Wear sunglasses to protect the skin around your eyes.
Avoid getting a tan and never use a tanning bed or sun lamp.

See more information on sun safety.

Learn more

Basal cell carcinoma DermNet NZ
Basal cell carcinoma patient information sheet British Association of Dermatologists

References

Telfer NR, Colver GB, Morton CA. Guidelines for the management of basal cell carcinoma Br J Dermatol. 2008; 159:35-48.
Skin lesion excision Auckland Regional HealthPathways, NZ, 2020

Reviewed by

	Dr Alice Miller trained as a GP in the UK and has been working in New Zealand since 2013. She has undertaken extra study in diabetes, sexual and reproductive healthcare, and skin cancer medicine. Alice has a special interest in preventative health and self-care, which she is building on by studying for the Diploma of Public Health with the University of Otago in Wellington.

Credits: Health Navigator Editorial Team. Reviewed By: Dr Alice Miller, FRNZCGP, Wellington Last reviewed: 11 Jul 2020 Page last updated: 07 Jun 2022

Information for healthcare providers on basal cell carcinoma

The content on this page will be of most use to clinicians, such as nurses, doctors, pharmacists, specialists and other healthcare providers.

Skin lesion management guidelines

Assess the likelihood of melanoma being present then provisionally identify the type of lesion. See skin cancer – clinicians
Surgical excision with histology is the first-line treatment for all skin cancer. It has the highest cure rate among available treatments. For BCC, the recommended margin for excision is 2–3mm with well-defined border, or 4–5mm with unclear border.
Referral, according to local guidelines, to a general practitioner with a special interest (GPSI) in skin lesions, a dermatologist, a plastic surgeon or an ENT surgeon may be appropriate for patients with:
- large or clinically ill-defined lesions
- recurrent or incompletely excised lesions
- difficult or high risk anatomical location (eg nose, ear, lip, eyelid)
- lesions with an aggressive growth pattern (eg, perineural invasion, BCC with infiltrative or micronodular growth patterns).
Patients with superficial basal cell carcinoma or intraepidermal carcinoma (squamous cell carcinoma in situ) may be safely managed with cryotherapy or topical treatments, ie, fluorouracil or imiquimod creams, when excision is not appropriate because of the location of the lesion or due to cosmetic considerations.
Topical treatments should not be considered if the diagnosis is uncertain.

Management of non-melanoma skin cancer in primary care

"Dr Diana North, Goodfellow GP Advisor talks with Dr Marcus Platts-Mills, Dermatology and Skin Cancer Surgery specialist, about the management of non-melanoma skin cancer in primary care."

(Goodfellow Unit, NZ, 2017)

Topical treatments for non-melanoma skin cancers

Source: Managing non-melanoma skin cancer in primary care – a focus on topical treatments BPAC, NZ, 2013

Table 2: Topical treatments regimens in primary care for superficial basal cell carcinoma (BCC)

Treatment type	Regimen for BCC
Cryotherapy	Apply liquid nitrogen to the skin for 20 – 30 seconds, allow to thaw for three to five minutes, then refreeze for another 20 – 30 seconds. Unsuitable for facial lesions, due to poor response rates, or distal lower limbs, due to persistent ulceration. Recurrence at the lesion margin may develop following cryotherapy.
Imiquimod cream (Special Authority)	Apply to the lesion and 1 cm beyond, once daily on five days each week, for six weeks. Treatment should be reviewed by at least the third week, to adjust the frequency of application. After a four week treatment break, treatment can be repeated for another six weeks if the response to the first course is incomplete. Imiquimod can cure 70 – 80% of small, superficial BCCs.¹⁰A punch biopsy should be performed where possible to confirm a diagnosis to qualify for Special Authority subsidy criteria. Imiquimod is indicated for superficial BCC on the neck, chest and distal upper limbs, but it appears to be less effective when used on the distal limbs. Imiquimod can be used to treat facial lesions but as local tissue reaction may be prolonged it may not be a desirable option for all patients.
Fluorouracil (5%) cream	Apply thinly to the affected area, twice daily, for 12 weeks.¹⁰Not routinely used to treat BCC, however, prolonged courses of treatment are occasionally used to treat small, very superficial BCCs.¹⁰

Guidelines for the management of basal cell carcinoma British Association of Dermatologists
Clinical practice guidelines for keratinocyte cancer Cancer Council, Australia, 2019

Regional HealthPathways NZ

Access to the following regional pathways is localised for each region and access is limited to health providers. If you do not know the login details, contact your DHB or PHO for more information: