mesothelioma externalised?

My 79 year old mother was diagnosed with mesothelioma 18months ago, and is now rapidly losing weight, coughing, hugely fatigued and in pain. We suspect that she has entered the final stages of her illness. My question concerns an area of skin just below her sternum, but also affecting the underneath of her breasts. It is knobbly, thick and very red, and appears to be growing quickly. Our General Practitioner is young, and relatively inexperienced, and treated her first for a fungal infection, then for shingles. When we saw her oncologist this week, she refuted both the fungal infection and the shingles, and said this looked very like the mesothelioma breaking through the skin, although she had never seen this with a mesothelioma before. Treatment is difficult as it is lying so close to the oesophagus. I would really just invite any comments from physicians who might have seen this before. Thankyou.