A Columbia surgeon's investigation was withdrawn. He continued to publish flawed data.

A series of ten by Dr. David identified articles showed repeated reuse of identical or overlapping black-and-white images of cancer cells, allegedly under different experimental conditions, he said.

“There's no reason to do that unless you didn't do the work,” said Dr. David.

One of those paper, published in 2012, was formally tagged with corrections. Unlike later studies, which were largely supervised by Dr. Yoon in New York, this article was written by South Korea-based scientists, including Changhwan Yoon, who was then working in Seoul.

An immunologist in Norway selected the article at random as part of a screening of copied data in cancer journals. That prompted the article's publisher, the medical journal Oncogene add corrections in 2016.

But the magazine didn't include everything duplicate data, said Dr. David. And, he said, images from the study later appeared in identical form another paper that remains uncorrected.

Copied cancer data kept coming back, said Dr. David. A photo of a small red tumor from a Study from 2017 reappeared in the papers 2020 And 2021 under different descriptions, he said. A ruler shown in the photos for scale can be wound in two different positions.

The 2020 study contained another tumor image of which Dr. David said it seemed to be a mirror image of it previously published by Dr.'s laboratory Yoon. And the 2021 study contained a color version of a tumor that had appeared in an earlier article superimposed on a different part of the ruler, said Dr. David.

“This is another example where this appears to have been done intentionally,” said Dr. Bik.

The researchers faced more serious action when publisher Elsevier withdrew the stomach cancer study that had been published online in 2021. “The editors determined that the article violated ethical guidelines for journal publishing,” Elsevier said.

Roland Herzog, the editor of Molecular Therapy, the journal in which the article appeared, said that “image duplications were noted” as part of a process of screening for discrepancies that the journal has since continued to strengthen.

Because the problems were discovered before the research was ever published in the print journal, Elsevier's policy dictated that the article be removed and no explanation posted online.

But that decision seemed to go against industry guidelines from the Publication Ethics Committee. Posting articles online “generally constitutes a publication,” according to these guidelines. And when publishers publish such articles, the guidelines say, they must keep the work online for the sake of transparency and post “a clear notice of retraction.”

Dr. Herzog said he personally hoped that such a statement could still be placed before the stomach cancer study. The journal editors and Elsevier, he said, are exploring possible options.

The editors brought Dr. Yoon and Changhwan Yoon were informed of the article's removal, but neither scientist alerted Memorial Sloan Kettering, the hospital said. Columbia did not say whether it had been told.