People with cancer that starts on the left side of their colon live significantly longer than those with right-side tumors, according to a new study. The retrospective analysis involved a federally funded clinical trial with more than 1,100 colon-cancer patients. Overall, it found that those with left-side tumors survived for a median of 33.3 months, while those with right-side tumors survived for 19.4 months. The data also turned up a striking difference in drug efficacy depending on the location of the tumors. Avastin was associated with longer survival times in cases of right-side tumors, while Erbitux was linked to longer survival with left-side malignancies.

Potatoes tied to hypertension

Eating potatoes four or more times a week may increase the risk for high blood pressure, a large new study has found. Researchers pooled results from three observational studies involving 187,453 men and women followed for more than 25 years. After controlling for lifestyle factors, they found that compared with eating potatoes once a month, having one potato — baked, boiled or mashed — four to six times a week increased the risk for hypertension by 11 percent. Eating four or more 4-ounce servings of French fries a week increased the risk by 17 percent.

Life expectancy is up 5 years worldwide

In the fastest gain since the 1960s, life expectancy worldwide has increased by about five years in the last 15 years, according to a report issued by the World Health Organization. The biggest increase was seen in Africa due to improvements in health care for children and the better availability of medicines, including those for malaria and AIDS. The U.N. health agency said that globally, life expectancy for a baby born in 2015 was 71 for women and 69 for men, with women in Japan and men in Switzerland typically living the longest. Sierra Leone had the lowest life expectancy for both genders.

New melanoma drug shows promise

A new kind of drug for the deadliest form of skin cancer helped some patients survive for at least three years, a study shows. It's a remarkable advance for patients who until recently faced dismal chances of living for more than a few months. About 40 percent of melanoma patients in the study were still alive three years later. The drug, which targets the immune system, was used to treat former President Jimmy Carter, who was diagnosed with melanoma that had spread to his brain. The drug, Keytruda, is among a new class of genetically engineered antibody-based medicines. They block proteins that prevent the body's disease-fighting immune system from attacking cancer cells.

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