July 28 (Reuters) - Bristol Myers Squibb Co (BMY.N) reported second quarter earnings that topped Wall Street estimates, as sales of flagship cancer treatment Opdivo returned to growth after missing estimates in the previous quarter. Excluding one-time items, Bristol Myers reported earnings of $4.3 billion, or $1.93 per share, beating analyst estimates of around $4.2 billion and $1.89 per share, according to IBES data from Refinitiv. Bristol Myers reported second quarter revenues of $11.7 billion, 16% higher than in the same period last year, driven in part by sales of Opdivo that exceeded $1.9 billion for the quarter, 16% higher than in the quarter ended June 30, 2020. "The highlight that is driving that strong performance is Opdivo and its return to growth," said David Elkins, Bristol-Myers" chief financial officer. Opdivo revenues benefitted from approvals in new tumor types and its increasing use as an initial treatment for advanced lung cancer, Elkins said. Bristol Myers" second quarter results mark a reversal from its performance last year, where a 3% decline in sales of Opdivo contributed to lower-than-expected earnings. read more Bristol Myers still expects full-year earnings in the range of $7.35 to $7.55 a share In the second quarter, Bristol Myers announced two deals with biotechs Agenus Inc (AGEN.O) and Eisai Co to develop and market new cancer drugs and it expects to do additional deals to build out its portfolio of medicines, Elkins said. "With the financial flexibility we have, we are really focusing on replenishing and diversifying the portfolio," Elkins said. He added that Bristol Myers is more likely to engage in deals for individual products as opposed to large scale corporate M&A. Revlimid, the blockbuster cancer drug Bristol Myers acquired in its $74 billion deal for Celgene in 2019, will lose some of its U.S. patent exclusivity in 2022, putting pressure on the company to add new products to its pipeline. The COVID-19 pandemic continues to affect Bristol Myers but the drugmaker saw a significant improvement in the second quarter in many of its businesses, said Chief Commercial Officer Chris Boerner.