After Jenna's birth, Schmirler experienced many health problems. She had suffered from back pain, which was thought to be pregnancy related, and following Jenna's birth, she began to suffer from stomach pains. Tests showed that a cancerous node the size of a fist had developed behind her heart. As her condition worsened, she underwent surgery on September 6, 1999. During surgery, a dead piece of the tumour broke off and released a blood clot into her lung. Her heart stopped beating, and only emergency heart massage kept her alive. Almost a month after being diagnosed with cancer, doctors finally provided a specific diagnosis – metastatic adenocarcinoma, with an unknown primary site. Because no one could pin down where the cancer came from, Sandra referred to it as "the cancer from Mars." In addition to chemotherapy and radiation, Schmirler explored orthomolecular medicine through the Canadian Cancer Research Group. This form of alternative medicine involves large doses of vitamins and nutrients.