During a police chase, while some cops are hot on the tail of a renegade car, others, a few miles ahead, will siphon off highways and side streets, creating blockades to stop the car.

The same logic applies to a new breast cancer study Ventura Oncologist Rosemary McIntyre, M.D., is conducting in conjunction with Amgen.

The Thousand Oak pharmaceutical company’s new drug, Motesanib diphosphate, is designed to police the body and stop cancer cells in their tracks, preventing blood vessels from forming new tumors.

“That’s why this study is important, because it’s changing the focus of how we treat cancer,” McIntyre said. “It’s not just blanket bombing and killing at random.”

“This will hopefully allow a person to live relatively normally despite having cancer.”

The targeted therapy approach is part of a shift in the way doctors are treating cancer, said Evan Slater, M.D., director of oncology for Ventura County Medical Center.

He said targeted therapy represents the “way of the future” for cancer treatment, because it attacks only cancer cells, unlike chemotherapy, which threatens normal cells in the body and often has negative side affects like hair loss and nausea.

“It’s the most exciting thing that’s happened in the last 50 years in oncology,” Slater said.

Since targeted therapy is a relatively new concept, researchers and pharmaceutical companies have been scrambling to come up with the best drugs and treatment methods. It’s still unclear whether targeted therapy works best when done alone or in conjunction with chemo, Slater said.

The two women who are enrolled in McIntyre’s study are taking one Motesanib diphosphate pill per day and are also receiving standard chemotherapy treatment. The local research is part of a worldwide study of several hundred people being conducted by Amgen on the effectiveness of the new drug, versus the effectiveness of a similar targeted therapy drug called A-Vastin, McIntyre said.

The local study began in October 2007, but researchers are still looking for more women with breast cancer that has metastasized, or spread to other parts of the body, to participate. The study, which runs through the end of this year, is open to women with the most common form of breast cancer, who have tested negative for the over-expression of HER2 gene, and who have not previously been treated with chemo for breast cancer.

McIntyre said her patients seem to be tolerating the Motesanib diphosphate pill well, but it’s too early to tell whether the drug has been effective in stopping tumor growth.

The results of the Amgen study likely won’t be published for a year or two after the study is completed, but some findings may be announced before then, if researchers see patterns in the data, McIntyre said.

According to the California Cancer Registry’s Cancer Facts and Figures, more than 500 women in Ventura County will develop breast cancer in 2008 and almost 100 will die from the disease.

Statistically, depending on a person’s race, breast cancer is diagnosed in the early stage 62 to 70 percent of the time in Ventura County, according to the CCR. That means approximately 30 to 38 percent of cases are diagnosed in more advanced stages, which require more complex treatments, like chemo or targeted therapy.

Jane Barbosa, a nurse and the mobile mammography coordinator for Ventura County Medical Center, said there is a need for more medical outreach to women in rural areas in the county.

Last October, she helped complete a 10-year project to get the Mobile Mammography Clinic up and running. The 44-long truck, which houses an analog mammography unit, travels twice weekly to underserved areas in Ventura County to provide low-cost mammograms to women 40 years and older.

McIntyre urges women to get an annual check-up to make sure breast cancer is diagnosed in its earliest stages.

“It can be cured if it’s caught early,” she said. “So women shouldn’t put off getting a check-up, especially if they’re afraid some irregularity might be cancer. The outlook is actually very promising for breast cancer. Most women will be cured.”