Marilyn Monroe X-rays sell for $51,650

Three X-rays of the chest and pelvis of actress Marilyn taken during visit in 1954 to Cedars of Lebanon Hospital have sold for $US45,000 ($51,650) - more than 10 times their pre-sale estimates.

The sale was part of an auction of Hollywood legends memorabilia which took place at the Planet Hollywood resort and casino in Las Vegas at the beginning of July.

Auction house Julien's said in a statement the X-rays were expected to go for $US800 to $US1,200 each.

The actress died in August 1962 at the age of 36. Other items also sold at the auction included a chair from Monroe's last photo shoot that went for $35,000, Christopher Reeves' Superman VI costume which sold for $32,500 and a dress worn by Audrey Hepburn in Funny Face which went for $56,250. The prices include the buyer's premium.