I truly hate cancer.
I often find my favourite patients being diagnosed with different types of cancer. One particularly nasty form of cancer is malignant melanoma skin cancer.
But there is hope and new treatments are being developed all the time. It is a quite common cancer formed from the cells in the skin that produce melanin, which darkens our skin. So, these tumours are often dark-coloured.
They are particularly common around the mouth and paws but can occur anywhere on the skin, including near the eye. The word malignant describes its capacity to ‘seed’ itself from one part of the body to other parts. This metastasis happens via the lymphatics and malignant melanomas love to settle in the lungs. So, we always keep a close eye on the local lymph nodes and the chest.
The best treatment has previously hinged on surgical removal of the primary lump, with follow-up chemotherapy to reduce the risk of metastasis.
However, a new therapy is available for dogs with malignant melanoma. It encourages the dog’s immune response and helps its white blood cells (the cells that fight off infections) to recognise and kill the tumour cells. Many types of tumours have developed mechanisms to evade or suppress the immune response and avoid being killed, but this new treatment tips the balance back in favour of the immune response.
One of the problems with any cancer therapy is that the tumour cells are related to and develop from our normal cells. It is difficult to find a therapy that will selectively kill the tumour cells but not the body’s normal cells. Malignant melanoma is a good target for this kind of therapy as melanoma cells are different from most other cells in the body, in that they produce pigment. So, vets can selectively kill the cancer cells, without damaging the rest of the patient, which is a huge advantage.
I hate cancer, but I love that I am working at a time when new possibilities like these are becoming available.
