* FY underlying profit A$118.5 mln vs A$122.4 mln f'casts
* Profit growth 28.8 pct vs guidance of about 32.5 pct
* Forecasts slower growth of 20 pct in FY 2018
* Shares slump 22 pct to 2-yr low (Adds CEO quote, background and results details by segment)
Aug 15 (Reuters) - Australian fast-food chain Domino's Pizza Enterprises Ltd DMP.AX , the biggest Domino's franchisee outside the United States, missed full-year profit expectations on Tuesday due to sluggish sales in Japan and France, sending shares to a near two-year low.
Sydney-listed Domino's also forecast slower earnings growth in the current financial year to June 2018, pointing to moderation in the spectacular growth which has made it a market darling since 2013.
The company's underlying net profit rose 28.8 percent for the year ended July 2 to A$118.5 million ($93 million), short of company forecasts for growth of 32.5 percent. It was also below the A$122.4 million average estimate of 11 analysts surveyed by Thomson Reuters I/B/E/S.
The stock plunged 22 percent in early trade to A$39.50, its lowest since 2015. The broader S&P/ASX 200 index .AXJO rose 0.5 percent.
The forecast miss was mostly caused by underperformance in France, Chief Executive Don Meij said in a statement.
"This was largely due to the delay in rectifying some issues with our online platform in France, and the initial response in H2 to our value range offering in France," he said.
Sales in Japan were also weaker than expected, he added, without elaborating.
Domino's forecast net profit to rise 20 percent in the 2018 financial year, with same store sales to rise in the range of 7 percent to 9 percent.
Domino's shares trade at a lofty price-to-earnings ratio of 51.65, compared with an average of 17.25 across the broader S&P/ASX 200 index .AXJO , making them particularly sensitive to earnings misses.
The company holds the franchise rights for Domino's in seven countries including the Netherlands, Germany and Japan. The Domino's brand is ultimately owned by U.S.-listed Domino's Pizza DPZ.N .
It also announced a A$300 million share buyback.
($1 = 1.2737 Australian dollars)