51˶

MedpageToday

Ovarian Cancer Survivors Face Increased CV Risks

– Venous thromboembolism risk almost 6 times higher than in general population, large study finds


This Reading Room is a collaboration between 51˶® and:

Medpage Today

Expert Critique

FROM THE ASCO Reading Room
Elizabeth May Nichols, MD
Elizabeth May Nichols, MD Assistant Professor, Clinical Director University of Maryland School of Medicine, Department of Radiation Oncology
Full Critique

One of the largest population-based cohort studies of its kind to date shows that adults who survive the most common site-specific cancers, including ovarian cancer, have a substantially increased medium- to long-term risk of one or more cardiovascular diseases.

Analysis of electronic health records from linked databases in the U.K. showed that 1 year after diagnosis, the risk of cardiovascular disease in 108,215 survivors increased by 50% or more following treatment for hematological, esophageal, lung, kidney, and ovarian cancers.

When compared with 523,541 matched controls without cancer from the general population, the incidence rate of venous thromboembolism per 1,000 patient-years (IR) was significantly increased (P<0.01) in 18 of the 20 most common cancer types.

As Krishnan Bhaskaran, PhD, of the London School of Hygiene & Tropical Medicine in the U.K., and colleagues note in their study online in , these represent more than 90% of all cancer diagnoses. In ovarian cancer survivors, the IR for venous thromboembolism was almost six times higher than in controls (16.7 vs 3.5; adjusted HR 5.77).

"Our findings show that more tailored strategies to minimize and manage cardiovascular risk are needed for people who survive cancer," the team wrote. "Prevention at early stages is a priority because the prognosis for cancer survivors diagnosed with cardiovascular disease is particularly poor."

Although 50% of cancer patients in high-income settings are expected to survive for at least 10 years, there is still concern about the risk of cardiovascular disease as a result of the of cancer treatment and shared risk factors, the researchers noted.

Following an exploratory analysis of survivor data by treatment type, they found that the elevated risk for cardiovascular disease in cancer patients was independent of treatment. The greatest risk, however, was observed in cancer survivors who had undergone chemotherapy -- indicating that chemotherapy may be the primary driver of cardiovascular disease in cancer survivors rather than shared risk factors such as body mass index and smoking.

The study also revealed an increased risk of heart failure or cardiomyopathy in 10 of 20 cancers. The adjusted hazard ratios (HRs) ranged from 1.72 in survivors of prostate cancer to 9.72 in those with pancreatic cancer.

In ovarian cancer survivors, the IR for heart failure or cardiomyopathy risk was 8.6 compared with 6.1 in matched controls (HR 1.67).

There was also an increased risk of arrhythmia, pericarditis, coronary artery disease, stroke, and valvular heart disease for multiple other cancers that persisted for 5 or more years. Once again, the analysis showed that ovarian cancer survivors were also at increased risk.

The risk of pericarditis was nearly four times higher in patients with ovarian cancer than in matched controls without cancer (3.91). Ovarian cancer survivors also had an increased risk for arrhythmia (HR 1.13), coronary artery disease (1.25), stroke (1.28), and valvular heart disease (1.15).

The HRs for heart failure or cardiomyopathy and venous thromboembolism were greater in younger patients and in those without previous cardiovascular disease. Still, absolute excess risks tended to increase along with patient age (2.1% per year in those 80 and older).

These findings are consistent with those from a in the U.S. of 36,232 cancer survivors in the Kaiser Permanente Southern California registry, the investigators noted.

The U.S. study showed a significantly increased risk of cardiovascular disease in survivors of breast and lung cancers, malignant melanoma, and non-Hodgkin lymphoma. No significant difference was found in survivors of nine other cancers, including ovarian cancer. Unexpectedly, a reduction in cardiovascular disease risk was seen in survivors of prostate cancer, the team said, adding that more staffed with oncologists, cardiologists, and specialist nurses will help to address this growing clinical problem.

Bhaskaran, et al. also emphasized the need to increase awareness among primary care physicians about the cardiovascular disease risks faced by many cancer survivors. For example, results from a in England showed that only one-fifth considered cancer in relation to cardiovascular health.

In an accompanying , Anne H. Blaes, MD, and Chetan Shenoy, MBBS, both of the University of Minnesota in Minneapolis, agreed that points to an increased risk of cardiovascular disease and death in the growing number of cancer survivors.

Although it has been known "for decades" that cancer treatments can elevate risk, newer therapies that cause can also contribute to cardiovascular outcomes, Blaes and Shenoy pointed out. In addition, cancer patients with underlying such as hypertension, advanced age, tobacco use, and diabetes have an increased risk for cardiovascular disease before they even begin cancer treatment.

Cardiovascular risk prediction tools that include cancer need to be developed, the commentators emphasized, adding that the study "clearly demonstrates" that clinical risk-assessment tools such as the Framingham risk score and Pooled Cohort Equations are not useful in the setting of cancer survival.

"The inclusion of cancer in these risk prediction tools, beyond the traditional risk factors for the prediction of cardiovascular disease risk, would add incremental value in the general population," Blaes and Shenoy wrote. "In the meantime, clinicians should account for cancer, and especially chemotherapy, as a risk factor for cardiovascular disease when discerning individual patient risks to guide preventive interventions."

The study by Bhaskaran, et al. was funded by the Wellcome Trust and Royal Society.

Bhaskaran reported a financial relationship with the Wellcome Trust and the Royal Society, the Medical Research Council, the British Heart Foundation, and Diabetes UK; co-authors reported relationships with industry.

Blaes and Shenoy reported having no potential conflicts of interest.

Primary Source

The Lancet

Source Reference:

Secondary Source

The Lancet

Source Reference:

ASCO Publications Corner

ASCO Publications Corner