An elderly gentleman came to the hospital with a tumor on his head. When asked how long the tumor had been there, he said 40 years!

So why, after 40 years, did he finally come to the hospital?
Over the past week, it had been growing significantly in size and it was painful. Besides that, an ulcerating wound had opened on the tumor and it was starting to bleed.
Since the man had lived with the tumor for 40 years, it did not appear to be an aggressive tumor, but I suspect it has had a malignant transformation (in other words, a benign tumor has become cancerous). On exam, the mass was nearly half the size of his head, attached to the scalp on the right. It did not feel like it was attached to the skull, and this was confirmed with an x-ray and ultrasound.

When the dressing was removed, maggots were squirming in the wound – a sign of dead flesh.

We began to excise the tumor and a rush of blood and clot came pouring out, but then stopped. I was able to remove the tumor down to the covering of the skull, noting that it did not breach this covering. The tumor itself appeared to be cancerous, but the center had been filled with a hematoma (old blood).

I believe the tumor had outgrown its own blood supply and started bleeding into itself. This expansion in size created the ulceration as the pressure on the skin prevented proper blood flow to that area – leading to the dead flesh which attracted the flies.
There was enough skin left at the end of the procedure to suture together and cover the exposed skull.
The nature of this tumor is still unknown. It may grow back in time, but at least for now, his burden has been lightened.