Rectal cancer and pulmonary embolism: Catherine O’Hara’s cause of death explained

In the wake of Catherine O’Hara’s sudden passing, it’s been confirmed that the acclaimed Home Alone and Beetlejuice actress died from a pulmonary embolism while privately battling rectal cancer. Her death serves as a tragic—but important—reminder of how complex and dangerous cancer-related complications can be.

According to Esther Cha, MD, colorectal surgeon at Trinity Health Mid-Atlantic Medical Group’s Surgical Associates Langhorne, a cancer diagnosis greatly increases a patient’s risk of developing a pulmonary embolism, which is when a blood clot gets stuck in an artery in the lung, blocking blood flow. Cancer patients are prone to pulmonary embolism because, when there are tumors in the body, excess clotting proteins are activated.

“It makes your bloodstream thicker,” explains Dr. Cha. “Having malignancy definitely raises that risk.”

If the blood clot is large enough and not treated in time, it can result in sudden death. O’Hara’s death certificate states that, within a few hours of symptom onset, she passed away at a hospital in Santa Monica, California, at the age of 71.

Symptoms of pulmonary embolism that individuals with cancer should look out for include shortness of breath, chest pain, elevated heart rate at rest, and leg swelling and/or stiffness. At St. Mary Medical Center, Dr. Cha teams up with medical oncologists to monitor patients. If they exhibit any of these symptoms, they are immediately sent to the ER for labs and imaging.

Though it comes with an increased risk of pulmonary embolism, rectal cancer itself—which is when a precancerous polyp or lesion becomes cancerous—generally has a good prognosis if caught early. However, while some patients may experience rectal bleeding or constipation, especially if the tumor has grown significantly, others might be unaware they even have it.

This is why screening is so important—a colonoscopy can detect those polyps before they become cancerous. Colorectal cancer screening guidelines recommend a colonoscopy beginning at age 45 for those with no family history. If everything looks normal, another isn’t needed for 10 years. A follow-up may be scheduled within six months to a year if polyps—whether precancerous or not—are discovered.

For those with a first-degree family history of colorectal cancer, meaning a parent or sibling was diagnosed, a colonoscopy is recommended every five years, even if it comes back normal.

“If your family member was diagnosed much earlier, let’s say at 40, then we suggest that you get screened 10 years prior to that diagnosis age. If your father was diagnosed at 45, then you will be screened starting at 35,” says Dr. Cha.

Compared to other types of colorectal cancers, rectal cancer oftentimes doesn’t require surgical intervention if caught early enough. Thanks to advanced chemotherapy and radiation, some rectal cancers can “melt away,” according to Dr. Cha.

“The reason is, rectal cancer is very confined to the pelvic inlet. It’s surrounded by lymph nodes, vasculature and, most importantly, pelvic bone,” she says. “Our goal is to shrink down the tumor before we go in operating. A special group of these patients are placed in a ‘wait and watch’ program and are under frequent surveillance to see if their rectal cancer comes back. If it does, only then does the surgical option get discussed.”

If surgery is needed, Dr. Cha is trained in minimally invasive robotic colectomy, which only needs a small incision. It offers faster recovery time for patients compared to the traditional laparotomy, which requires a large incision.

“You’re not depending on narcotics. You’re not in the hospital for 10 to 14 days. You get back to your life much faster. And if you do need chemotherapy, we can start that much sooner than if you’re still lingering in the hospital for two-plus weeks,” says Dr. Cha.

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