Dear Grace,
I advise you to drink blessed water. Your friend can bless the water with Vajra Armor mantra, by blowing on water in a large container every half mala. Visualize nectar coming from the deity’s heart purifying the four things: negative karma, disease (the tumor), spirit harm, and obstacles. Visualize very strongly that all of these are purified and keep repeating the process every half mala.

At the end of each session think strongly that all your negative karma since beginningless time is completely purified. Then visualize you have received all the realizations. Think that the deity Vajra Armor is one with His Holiness the Dalai Lama and all the gurus and buddhas. Do this with mindfulness.

Drink the water in the early morning, after breakfast, in the afternoon and evening. This is the minimum. Also, bless it each time before drinking it. Drink a few tablespoons each time.