Suspicious lesion on elderly female’s arm
This lesion had developed gradually over a year or so. Bear in mind that we are not always very good at remembering such details, less so as age advances, so although the history of the lesion is always our diagnostic starting point, one cannot expect the details as recalled to be very reliable. However, speed of development of a lesion even if only approximate is very important to diagnosis, for example a nodule which has come up over about 3 months is likely to be a squamous cell cancer, a lesion slowly growing over 2 years is more likely to be a basal cell cancer. For the sake of argument, this has developed gradually rather than rapidly, and has not always been there.
The dermoscopy was supportive of my working clinical diagnosis of Bowen’s disease. This is more common on the lower leg but can occur anywhere, especially sun exposed sites.
There is a pink background which might make us think of the differential diagnosis of superficial basal cell cancer, but look at the vessels. The typical arborising vessels of a BCC are absent, instead there are tightly coiled or dotted vessels. These are possible seen better in the next image which has been brightened digitally using Microsoft Office Picture manager.
Also, you do not get organised keratin on a basal cell cancer, the occasional small flake of scale perhaps but there is too much keratin on this lesion for a BCC. As is is not fast growing or elevated enough for a squamous cancer, it has to be Bowen’s disease (intra-epithelial squamous neoplasia). These lesions are considered premalignant and it is thought that SCCs arising from Bowen’s lesions are more aggressive.
The lesion was excised as it was thought that this would cause less morbidity and be a simpler and quicker solution for the frail elderly patient than a course of 5-fluorouracil or imiquimod cream, either of which would probably have worked but caused a significant reaction.
Histology confirmed Bowen’s disease.