2 June 2021

Frank went in for a Covid jab, but what he got was a diagnosis that may have saved his life

Everyone undertaking immunisation sessions is aware they are saving lives. For Frank’s astute vaccinator, this was doubly true.

By Phil Whitaker

“I was having my Covid jab,” Frank explained, “the nurse saw this thing and said I should get it checked.”

I waited while he rolled up his sleeve. There, near the top of his left arm, close to where a vaccine would be injected, was a stark black lump, about 7 millimetres across. It was surprisingly soft in texture, but ringed with a halo of redness where the surrounding skin was inflamed.

“How long’s it been there?”

“About a year, I’d say. I haven’t really taken much notice.”

I had a look with the dermatoscope, which affords magnified views under polarised light. Normally, that provides a great deal more detail about the architecture of skin lesions. This one just looked homogeneously black.

“I think we’d better see what the dermatologists say.”

The pandemic has had some silver linings. Pre-Covid, any suspicious moles would have been referred under a fast-track system known as the two-week wait (2WW). Our local dermatology department was buckling under the sheer number of patients to be seen. Covid spurred the development of an app through which we can send plain and dermascopic photos and get a consultant opinion the same day. “Teledermatology” has drastically eased the strain on the department. I knew what the outcome was going to be with Frank, though. The consultant agreed: this could be a nodular melanoma. They would see him urgently.

Malignant melanoma is the most feared form of skin cancer. It metastasises readily, spreading to other parts of the body where it will ultimately prove fatal. And it can also be very hard to detect. Classic cases are obvious, but melanomas can be very subtle, particularly the flat “superficial spreading” variety.

There are also a couple of rare variants that can trip up the unwary. One is naevoid melanoma, which looks like a different, benign blemish called a seborrhoeic keratosis and is frequently misdiagnosed. I was nearly caught out by one a few years ago. Fortunately, the golden rule of always sending samples for histology saved the day. The pathologist was able to pick up subtle signs under the microscope that revealed the true nature of the blemish. Further surgery ensured complete clearance, and the patient remains disease-free to this day.

The other variant is an amelanotic melanoma. In these, the cancer cells have lost the ability to produce the characteristic black-brown melanin pigment, so the tumour looks completely unlike a melanoma. I’ve only had one case, back in my early years as a GP. It was affecting the nose of an older patient. This was in the days before dermascopy; with the naked eye it looked like a basal cell carcinoma (BCC), an essentially harmless form of skin cancer that virtually never metastasises and is readily curable with minor surgery.

The thing that gave me pause, though, was the speed of growth. BCCs change only very slowly, whereas this lesion had grown markedly in a just a few months. My patient had to endure a series of major operations first to clear the primary tumour and subsequently to reconstruct his nose. Sadly, the melanoma latterly proved to have metastasised, and became a terminal condition over the next couple of years.

Frank had his lesion excised by the dermatologists right there in clinic, and histology confirmed nodular melanoma. At present there is no indication that the tumour has spread, so hopefully the surgery will have cured him. It wasn’t something he was intending to bring to medical attention until he went for his Covid jab. Everyone undertaking immunisation sessions is aware that they are saving lives. For Frank’s astute vaccinator that day, this was doubly true.