(AP) -- Concerns are being raised about the validity of research done by a Duke University cancer scientist who recently was placed on leave while the school investigates whether he falsely claimed to be a Rhodes scholar.

The editor of a British journal, Lancet Oncology, issued an "expression of concern" Friday about a 2007 study by Duke's Dr. Anil Potti. It described that may help predict who most needs .

The journal says that some of Potti's co-authors contacted them this week with concerns about the report, which the medical journal is now investigating. Neither the scientist nor Duke officials could immediately be reached for comment.