It's no surprise that access to new cancer drugs varies from country to country. But can this discrepancy be to blame for poor survival rates in some countries?

A controversial report from Sweden's famed Karolinska Institutet, which claims that access to the newest cancer drugs enhances survival, has triggered a spat between the report's authors and experts who say the report's conclusions are based on faulty analysis.

The report, first published in 2005 by the institute and updated in a June supplement in the Annals of Oncology, includes a chapter that examines the impact of a drug's 'vintage', the year it is first launched, on cancer survival in five European countries and concludes that cancer patients with access to the newest drugs live longer (Ann. Oncol. 18, iii1–iii77).

Michel Coleman, professor of epidemiology at the London School of Hygiene & Tropical Medicine, says the researchers' methods are so flawed that the report should never have made it past the peer review process. “Just because the Karolinska institute is famous doesn't mean that everything that's published with its name on it is necessarily correct or laudable,” he says.

Quality of care: Can access to the newest cancer drugs improve survival? Credit: Heather Stone/Chicago Tribune/MCT

In the same journal's September issue, Coleman points out that the report was funded by pharmaceutical giant Roche and lambasts the authors' methods (Ann. Oncol. 18, 1433–1435). For example, Coleman questions the report's use of survival data from the early 1990s and drug access data from 2002 on. “How in the name of heaven can you draw any kind of causal conclusion that survival is somehow the result of the access to the drugs when the latter postdates the former by ten years?” he asks.

The UK's National Institute for Health and Clinical Excellence, the agency responsible for deciding which new drugs should be provided by the government, also publicly rebuked the authors. “This drug industry–sponsored report is flawed, inaccurate and directly contradicts itself in places,” Andrew Dillon, the agency's chief executive, said in a statement in May.

Ulrik Ringborg, director of Karolinska's Cancer Center, would only say that the chapter has “tremendous methodological problems”. “I cannot say they are wrong, I cannot say they are right because the methodology is not perfect.”

The primary author of the controversial chapter, Columbia University economist Frank Lichtenberg, says the strong relationship between survival rates in different countries and drug vintage makes the conclusions more persuasive. “I quite frankly don't think that Coleman understands the techniques that we're using,” Lichtenberg says.

Lichtenberg says he isn't surprised by the backlash, which he sees as a knee-jerk response. “Many people are highly critical of the pharmaceutical industry and anything that sounds like a positive message about the role of the pharmaceutical industry in society,” he says.

Isabelle Durand-Zaleski, a health economist at the Hôpital Henri Mondor in Paris, notes that speedy drug access could be a marker of other factors that prolong life, such as better diagnostic facilities or a country's overall willingness to deal with disease. But the important thing, she adds, is that the debate will inspire more research.

Coleman couldn't agree more. “Critique is the substance of science,” he says. “We'd never get anywhere if we all believed everything we saw in print.”