By Katherine Sayre

Casino magnate and Republican Party megadonor Sheldon Adelson is stepping away from his Las Vegas Sands Corp. for cancer treatment, leaving his company amid economic uncertainty in the global gambling industry due to the Covid-19 pandemic.

Mr. Adelson, 87 years old, founded Las Vegas Sands and continued leading the company after being diagnosed with non-Hodgkin lymphoma, which the company announced in March 2019. The billionaire is taking medical leave to resume his cancer treatment.

Mr. Adelson, whose family is majority owner of the company, has said his succession plan is for the current executive team, including 25-year Sands veteran Robert Goldstein and Mr. Adelson's son-in-law Patrick Dumont, to lead the company, according to a person familiar with the conversations.

Mr. Goldstein, who most recently was chief operating officer and president, was named by Sands's board of directors as acting chief executive and chairman during Mr. Adelson's medical leave, the company said Thursday. Mr. Dumont joined the company in 2010 and is chief financial officer and executive vice president.

Las Vegas Sands operates casino-resorts on the Las Vegas Strip, in the Chinese territory of Macau and in Singapore. As Covid-19 first swept around the world last year, casino closures and pandemic restrictions wiped out gambling company revenues. Las Vegas Sands's revenue plummeted 82% in the third quarter of last year compared with the same quarter of the previous year.

Revenues have begun to recover, particularly in casinos across the U.S. that rely on regional customers, thanks in part to pent-up demand. The industry in Las Vegas, meanwhile, has continued to struggle. Casinos on the Strip rely on business conventions and long-distance vacationers, two segments that remain dampened under the continuing spread of Covid-19.

In October, Sands said it was considering selling its Las Vegas properties, which include the Venetian, the Palazzo and a large convention center. Mr. Adelson and partners bought the old Sands Hotel in Las Vegas in 1989. Inspired by his honeymoon to Venice, Mr. Adelson demolished the hotel in 1996 and built the Venetian, an Italian-themed megaresort. In 2004, Mr. Adelson opened his first megaresort in the gambling hub of Macau.

Even as the company has considered a Las Vegas exit, executives have been looking to expand into other potential markets, including eyeing Texas and New York City.

Meanwhile, in Macau, Sands and other resort operators are waiting for the Macau government to lay out how casino licenses will be reissued. The current licenses are set to expire in June 2022. Sands generated 64% of its revenue from Macau in 2019.

"What does today's executive appointment mean operationally and strategically?" said JP Morgan analyst Joseph Greff in a note Thursday. "We don't think anything changes at [Las Vegas Sands] and have long viewed Rob Goldstein as 'the next man up.'"

The Adelson family held nearly 57% of the company's stock as of March 2020.

Mr. Adelson and his wife, Miriam, have been among the top donors to the Republican Party. Most recently, the Adelsons donated more than $75 million to President Trump's failed re-election campaign. Mr. Trump awarded Ms. Adelson, a physician who founded drug abuse treatment and research centers, the Presidential Medal of Freedom in 2018.

Las Vegas Sands shares ended Thursday's trading 0.7% lower.

Write to Katherine Sayre at katherine.sayre@wsj.com

(END) Dow Jones Newswires

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