Help Porter fight cancer

Hi, Porter is our 2.5 year old Boxer (the brindle one in the picture). In January, he started to limp and favour his hind left leg. Multiple vet visits and x-rays led us to believe he had what was the equivalent of an ACL tear in humans. March 1st was his scheduled surgery date, but during pre-op inspection the surgeon and vet found that there was a growth around the knee area that was actually causing lesions on the bone. March 8th, he was formally diagnosed with cancer, we suspect Osteosarcoma. He's having the leg amputated March 22nd, followed by chemotherapy. Surgery and treatment estimates are between $12,000 and $15,000. Porter is a part of our family and we want to be able to give him his best shot at what time he has left with us.