Bowen's disease = intraepidermal carcinoma = IEC = Squamous cell carcinoma in-situ
Read our Bowen’s disease article in the BMJ 2020
The term squamous cell carcinoma in situ (SCC in situ) perhaps more accurately reflects what Bowen’s disease is.
Bowen’s disease shows precancerous changes throughout the whole thickness of the epidermis
Bowen’s disease was described in 1912 by Professer JT Bowen
Bowen’s disease is a precancerous lesion
in-situ refers to the fact that the disease has not penetrated the basement membrane.
Once this occurs, the lesion is a squamous cell carcinoma a full blown skin cancer.
Bowen’s disease typically presents as an asymptomatic, slow growing, sharply-demarcated, scaly erythematous (red, pink, salmon coloured) patch or plaque. The border may be irregular.
The surface may be flat, scaly, crusted, eroded, ulcerated, velvety or verrucous (warty).
Because of its asymptomatic nature, lesions may become very large by the time of presentation.
BD occurs most commonly in later life and most patients are aged over 60.
Although BD can occur just about anywhere, common sites for presentation are the lower limbs and head and neck,
Women are affected more than men
It has traditionally been thought that about 3-5% of Bowen’s disease transformed to SCC. However recent data suggests that this might be as high as 16% (Varma S. Reply to: Frequency of squamous cell carcinoma in situ (SCCIS) and SCC in re-excisions of biopsy-proven cutaneous SCCIS. Br J Dermatol 2018; 179: 223-224.). About 1/3 of these SCC are thought to metastasise (spread to other parts of the body)
Treatments for Bowen’s disease
|For Bowen’s disease there is no right or wrong way to treat.
|Individualizing to the patient and lesion are the key
1. No treatment
Given that only 3% of Bowen’s disease progresses to invasive squamous cell carcinoma then no treatment could be considered an option in some elderly frail patients with co-morbidity or with a limited lifespan. In other words, it may be kinder to do nothing.
Lesions especially suitable for no treatment are those that are thin and considered unlikely to progress to squamous cell carcinoma and those located on sites where healing is a problem
5 Fluorouracil (5FU 5%cream = Efudix)
Several open studies have shown 5FU to be efficacious in clearing BD.
Cure rates of 66-93% have been reported
The highest cure rates are achieved when Efudix is applied once or twice daily for 6-16 weeks and included a margin around the lesion
There is a lot of variability in the way Efudix is prescribed with some Physicians recommending it twice a day, every day, others every other night or twice weekly and for differing lengths of treatment
Efudix sometimes produces irritation, inflammation, erosions and ulcerations, so less aggressive regimens have been suggested. But these regimens give higher recurrence rates.
This is a quick and simple method to treat IEC with usually excellent success rates for small IECs in sites that heal well. The benefits of cryotherapy should be balanced against the risk of creating an ulcer that may take a long time to heal (e.g. BD on lower leg of elderly female).
|is an excellent treatment for Bowen’s disease.
|Its a simple, quick and inexpensive procedure
|High cure rates have been quoted
Recurrences may be attributable to the experience of the surgeon or to repopulation by Bowen’s disease cells from hair follicles, sweat gland etc
Generally cure rates are similar to other treatments with some advantages.
A report in the British Journal of Dermatology a few years ago showed the superiority of curettage and cautery over cryotherapy in the treatment of Bowen’s disease especially lower leg
In selected cases curettage and cautery can give
||shorter healing times
||Lower recurrence rates than cryotherapy
For well defined small lesions where excision and primary closure can be performed surgery is a good option
But one has to be careful as lesions on the lower leg can be large and the skin is poorly vascularised skin where healing can be a problem one risks dehiscence or necrosis or skin grafting adding to morbidity
The recurrence rates for Bowen’s disease removed by simple excision is between = 5 –20% and may be related to subclinical extensions
Mohs micrographic surgery – excellent for large lesions, or where tissue sparing is vital eg younger patients but expensive and time consuming
Recurrence rates are lower with Mohs micrographic surgery.
The problem c destructive surgical techniques such as Curettage and cautery, cryo and Ablative lasers is that no tissue is available to confirm complete removal. Results are generally good but in the case of lasers to require special eqiuipment and trained staff
Bowen’s disease is reported to be radiosensitive
Various forms of ionising radiation have been used
Cure rates = 89-100%
||Management of large and multiple lesions
||Especially in elderly, infirm or those on anticoagulants (blood thinners)
||Inadequate treatment at deep margin leads to recurrence s
||Problem c healing – esp lower leg
||Poor healing associated with diameter of radiotherapy field, dosage and energy of radiation, patient age >90
Photodynamic therapy (PDT)
In the last decade PDT has shown considerable promise for the treatment of premalignant skin conditions such as Bowen’s disease.
a topical photosensitiser precusor is applied to a lesion
this is preferentially taken up by tumour cells and converted to a potent photosensitiser the lesion is then irradiated with light activating the photosensitiser
and the tumour is destroyed.
Several studies have shown topical PDT to be effective in the initial clearance of Bowen’s disease.
|Long term follow-up
|cosmetic results are usually excellent
|consider it for
|large lesions, on poorly vascularized skin
|If other treatments don’t seem feasible
|For those patients unsuitable for surgery
|But it is time consuming
|repeated treatments can be necessary
|see B.A.D. Guidelines on PDT
|This is the treatment of choice for single or large IEC or for those on poorly vascularised sites
Imiquimod (Aldara) [not licensed for IEC]
||This is an immune response modifier, rather than inhibiting and suppressing the immune system it stimulates it.
||Demonstrates potent antiviral, anti-tumour and immunoregulatory properties.
In one study, 16 patients with Bowen’s disease applied Imiquimod o.d. 16 weeks.
Lesions were up to 5.5 cm in diameter. 15 legs 1 shoulder
6 weeks after treatment 14/15 patient’s biopsies showed no residual tumour.
Patients did experience local skin reactions similar to 5-fluorouracil
6 patients stopped early because of local skin reactions
Ablative Laser (CO2, erb:YAG laser)
This can be useful for selected Bowen’s disease.
Mohs micrographic surgery
I have removed several IEC/ Bowen's disease of the nail or finger with Mohs surgery. It is important to establish that the lesion is not a full blown SCC. Benefits of Mohs include tissue sparing and complete IEC removal.