Michael Weitz knew something was wrong.

The longtime Santa Monica physician was sitting outside when he felt unusual pain in his chest after swallowing cold liquid, and he figured he probably had cancer.

“I had this sixth sense,” he said, a bronchoscopy later confirming his dark suspicions.

That was about 10 years ago. For Weitz, who now has one lung, it’s a marvel considering he was told he had no more than six months to live. The 59-year-old remains director of the emergency department at Providence Saint John’s Health Center, and he’s committed to the fight against one of the most common killers in the country.

Weitz’s story is one piece in the mosaic of cancer’s devastating impact in Los Angeles County, where more than 1.3 million cancer patients were diagnosed between 1976 and 2012.

That’s according to a report that was recently released by the Los Angeles Cancer Surveillance Program, a project of the USC Norris Comprehensive Cancer Center and the university’s Keck School of Medicine.

The incidence of lung cancer has “substantially declined” since the mid-1990s, according to the report, a trend that has been attributed in part to a decline in smoking. But lung cancer remains the leading cause of cancer death in the U.S., data show, and survivor rates are extremely low.

“Because cancer is such an important health problem and is costly in terms of treatment and social costs such as loss of work time and quality of life, it is important to have a clear idea of the changing burden of cancer on society,” the report reads. “Keeping an eye on cancer rates provides clues about the causes of cancer, how successful we are at preventing cancer, and where we should focus our efforts in the future to make cancer a disease of the past.”

It will probably never be a disease of the past for Weitz, who over the last decade has had several operations and tried numerous treatments with varying degrees of success.

Initially, doctors weren’t sure he had cancer. A chest X-ray was taken. A CAT scan was administered. But the bronchoscopy led to a diagnosis of adenocarcinoma in his chest, which necessitated a conversation with his three children. Weitz, who never smoked, then went through chemotherapy before an operation to remove his left lung.

“My stamina got better, and my body accommodated having one lung,” he said, noting that he can’t run and that he occasionally gets shortness of breath. “The body is incredibly adaptable.”

Weitz was doing relatively well with a drug treatment until he started having difficulty reading a computer screen, and he started radiation therapy after an MRI confirmed his fear that cancer had spread into his brain.

He later turned to a clinical trial for a drug that his mother learned about while watching a television news segment. The drug was reportedly successful for a patient with a specific mutation, which Weitz later learned he had. The drug worked for four and a half years.

Weitz then started on another medicine that he’s taken for almost two and a half years, and he’s continued on the Alectinib regimen after undergoing a craniotomy last year to mitigate swelling in his brain.

“For 50 years nothing really evolved,” he said of cancer treatment options. “Now there are so many new drugs. If you fail one, there’s another one. I feel badly for those who never had this opportunity. I’ve been incredibly fortunate. I thought it was a bad dream, but now [cancer is] not part of my daily routine.”

Weitz now does outreach through the Lung Cancer Foundation of America, sharing his story with other patients. He urges them not to lose hope and reminds them, he said, that “no one has a crystal ball.”

Weitz’s goal is to turn what seemed like a death sentence into a manageable chronic disease. He said he encourages fellow lung cancer patients not to be afraid of clinical trials for new treatments.

“I don’t think I’ll ever be cured, but I don’t think I need to be cured,” he said. “We’re just on the precipice of amazing new discoveries. Immunotherapy, coupled with targeted therapies, can help, and no one can tell you how you’re going to do.”