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Authorities have released the cause of death for actor Sherman Hemsley, who died last month at age 74.

A statement from the coroner's office in El Paso, TX, states that Hemsley died from a complication of lung cancer known as Superior Vena Cava Syndrome. The illness is triggered by an obstruction that causes a narrowing or blockage of the second largest vein in the body.

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The Golden Globe nominee -- perhaps best known for his role as George Jefferson -- passed away at his home in El Paso on July 24. Hemsley first broke into television in 1973, appearing on All in the Family, and his character's popularity earned him his own spinoff, The Jeffersons. 

During its 10-year run, the program broke barriers as the first prim time show to star an upscale African-American couple. The show was also ahead of its time in casting the first interracial couple on a major sitcom.

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