He is perhaps best known for his work on laetrile, a controversial alternative cancer treatment, which he was convinced had a palliative effect on certain mice tumors.
[1] In 1972, Memorial Sloan-Kettering Cancer Center board member Benno Schmidt convinced the hospital to test laetrile in order to assert its ineffectiveness "with some conviction".
The initial positive results were not published because, in the words of Chester Stock, Sugiura's supervisor, "it would have caused all kind of havoc."
Mistakes in the Sloan-Kettering press release were highlighted by a group of laetrile proponents, led by Ralph W. Moss, former public affairs official of Sloan-Kettering hospital, who was fired when he announced his membership in the group.
These mistakes were considered inconsequential, but Nicholas Wade in Science noted that, "even the appearance of a departure from strict objectivity is unfortunate.