PathVysion: Advanced Diagnosis Leading to Targeted Therapy

According to the National Cancer Institute, one in eight women born today will be diagnosed with breast cancer at some point in her life. A diagnosis of breast cancer — the second-most-deadly form of cancer affecting women — is a traumatic and frightening revelation for patients and their families. While advances in testing and types of treatment have steadily improved chances of survival over the past several decades, some patients suffering from an aggressive form of the disease have not responded well to these therapies. Among this subset – approximately 25 percent of all breast cancer patients – multiple copies of a specific gene cause "overexpression" of proteins that are a key factor in tumor growth.

In the early 1980s, a molecular biologist at the Massachusetts Institute of Technology discovered that certain genes found in rat tumors acted as triggers, transforming other healthy cells into cancerous cells. Several years later, scientists discovered a human counterpart to these genes while trying to understand why 30 percent of breast cancer patients did not respond well to traditional therapies. This study found that the cancer cells in these women had multiple copies of the HER-2 gene. Tumors in patients with this gene can be faster growing, more aggressive and less sensitive to chemotherapy and hormone therapy.

Although a treatment designed to specifically target HER-2 patients was introduced in 1998 (Genentech’s Herceptin®), imprecise diagnostic tools made it difficult to accurately identify women who could most benefit from this treatment. One small company, Vysis, had developed a breakthrough diagnostic tool called PathVysion to test for HER-2. PathVysion is built upon a proprietary technology known as fluorescence in situ hybridization, or FISH, which uses fluorescent dyes to illuminate the HER-2 genes present in a cell’s nucleus. Using a microscope, physicians can count the number of HER-2 genes. If more than one copy is present, the patient has an overexpression and could be considered a candidate for Herceptin therapy. While the science behind PathVysion represented a significant advance, Vysis did not have the resources to produce and distribute the test to health care providers and patients throughout the world.

Abbott saw the work at Vysis as crucial to the successful treatment of many breast cancer patients. We also realized that as long as the number of correct identifications of the HER-2 gene in breast cancer patients remained low due to a limited availability of diagnostic tools, the lives of a significant number of breast cancer patients remained in jeopardy. Abbott purchased Vysis and, using our vast distribution channels, made PathVysion readily available to physicians and patients around the world, enabling physicians to quickly and accurately identify the best possible treatment options for their breast cancer patients.