Kathmandu, June 15 -- Vital chemotherapy drugs used around the world have failed quality tests, leaving cancer patients in more than 100 countries at risk of ineffective treatments and potentially fatal side effects, the Bureau of Investigative Journalism (TBIJ) revealed this week.

The drugs form the backbone of treatment plans for numerous common cancers - including breast, ovarian and leukemia. Some drugs contained so little of their key ingredient that pharmacists said giving them to patients would be as good as doing nothing.

Other drugs, containing too much active ingredient, put patients at risk of severe organ damage or even death. "Both scenarios are horrendous," said one pharmacist. "It's heartbreaking."

Doctors from multiple...