This 69-years old lady had been treated in the past for Ca vulva and presented with swelling in the left limb. The CT scan showed a mass encasing the iliac vessels. It was highly necrotic, with one apparently solid component next to the left ureter.

While it is very easy to biopsy this lesion, the issue is to get into a non-necrotic component, which was a small component anteriorly (green arrow). That biopsy too is simple, but these issues need to be sorted out in advance to ensure that we get diagnostic, representative material.

Rule: Always try and biopsy the non-necrotic component. It seems obvious, but so many times, we see this rule being flouted.
The diagnosis was metastasis from Ca vulva.