Thompson made the disclosure as he was facing pressure to leave from investor Third Point Llc, said the person. Yahoo reported Sunday that Thompson had stepped down. His exit follows criticism his official biography included a college degree he never received.
The cancer disclosure was previously reported by The Wall Street Journal. The newspaper, citing people it did not identify, said Thompson told Yahoo's board and several colleagues of his condition before resigning.
The newspaper said it was told by one source that Thompson's decision to resign was partly influenced by his cancer diagnosis.
Thompson was hired as Yahoo's chief executive in January to fill a void created by Carol Bartz's firing.
Yahoo Inc. has named Ross Levinsohn, an executive in charge of its media operations, as its interim CEO. Levinsohn had a successful stint running Internet services within Rupert Murdoch's media empire at News Corp. before Bartz hired him in November 2010.
Combined wire services