Health researchers at Temple University say doctors may need to consider two new risks as they care for people with colon cancer.

 

People with colon cancer who also have either diabetes or high blood pressure are more likely to die from their cancer, or have the illness come back after treatment, compared with colon-cancer patients without those two conditions.

That's the conclusion from Temple Health surgical oncologist Nestor Esnaola and his team. The investigators reviewed more than 36,000 thousand medical records.

"Perhaps patients that have early stage colon cancer that are diabetic or have hypertension may warrant closer cancer surveillance, i.e. follow-up," Esnaola said.

Having diabetes or hypertension may move some colon-cancer patients into a higher risk group, he said, and perhaps make them candidates for more aggressive treatment such as chemotherapy.

Edith Mitchell, an oncologist with Thomas Jefferson's Kimmel Cancer Center, said the new study is provocative and "very well done." But after reading the research, she did not reach the same conclusion as the study authors.

"I think additional studies will need to be done to actually prove their hypothesis that these patients need more aggressive surveillance," Mitchell said.

She cautioned that drawing conclusions from a study of Medicare data on elderly patients could be tricky.

"Many of these patients are too sick -- and have other comorbid conditions -- to receive chemotherapy," Mitchell said.

Esnaola's team set out to understand the influence of a cluster of conditions related to heart disease called metabolic syndrome. Patients with that illness often have some combination of obesity, high blood sugars, hypertension and abnormal cholesterol.

In an effort to improve health outcomes for patients with colon cancer, Esnaola said some doctors might consider managing a patient's high blood pressure or diabetes more closely with medicine or diet. It's not clear, though, if that approach is effective.

"Honestly, we don't have an answer to that," Esnaola said.

Some research suggests that medicines -- such as metformin -- used to lower insulin levels slow cancer growth and progression.

"And, there's less evidence that beta blockers that treat hypertension are helpful," Esnaola said. Research has also linked weight management to better outcomes for women with breast cancer.

"So, it's possible that weight loss could be equally beneficial with patients with colon cancer, as might metformin therapy and statin therapy," Esnaola said.

The Temple study findings are published in the latest online edition of the journal Cancer.