Dr. Hamer discovered the true trigger for cancer in the body as an undealt-with old emotional trauma in the brain. This causes a reversal in polarity and correlates to which organ the cancer cells begin growing in. With holistic methods, we can help track down the cause and the re-polarize the areas to help the healing process begin.
Bad diet, environmental pollution, genetics and epi-genetics, cellular pH acidity and hormonal imbalances also...but buried emotions care definitely a factor.