* IMF says major differences remain with Greece
* May retail sales rise 1.2 pct vs est 1.1 pct
* Citrix jumps after investor sends letter to board
* Twitter rallies after hours; CEO to step down
* Indexes up: Dow 0.2 pct, S&P 0.2 pct, Nasdaq 0.1 pct (Updates close with latest volume, details on Twitter)
By Caroline Valetkevitch
June 11 (Reuters) - U.S. stocks climbed on Thursday as retail sales data lifted the outlook for consumer spending and as healthcare shares gained.
Shares of Eli Lilly, Gilead and other healthcare stocks gave the S&P 500 its biggest boost, while the S&P 500 healthcare index gained 0.5 percent and was among the day's best-performing sectors.
Eli Lilly hit a 14-year high, closing up 4.1 percent at $86.59, with investors anticipating data from an extended trial of an experimental Alzheimer's drug that could become available to doctors in the coming weeks. The stock is up 10.3 percent since Monday's close. Gilead rose 1.2 percent to $119.13.
S&P utilities rose 0.7 percent, the day's strongest sector, as U.S. bond yields retreated. Utilities and other dividend payers tend to compete with bonds for investment money.
U.S. retail sales increased 1.2 percent in May, more than expected, as households boosted purchases of automobiles and a range of other goods even as they paid a bit more for gasoline. The S&P retail index was up 0.2 percent.
"You had good retail sales today and slightly above expectations. Remember how weak retail sales were in the winter, so you would expect a bounceback here," said Tim Ghriskey, chief investment officer at Solaris Group in Bedford Hills, New York.
The Dow Jones industrial average rose 38.97 points, or 0.22 percent, to 18,039.37, the S&P 500 gained 3.66 points, or 0.17 percent, to 2,108.86, and the Nasdaq Composite added 5.82 points, or 0.11 percent, to 5,082.51.
Solid retail sales data followed robust May job growth numbers and stabilizing manufacturing activity, suggesting the economy is gaining momentum after a slow start in the second quarter.
The market stayed cautious over Greece. The International Monetary Fund said its delegation had halted negotiations in Brussels and flown home because of differences with Athens.
Citrix Systems rose 6.7 percent to $70.39 after shareholder Elliott Management said the software maker should sell some units, cut costs and buy back shares.
Krispy Kreme soared 13.9 percent to $19.81. The doughnut chain raised the bottom end of its 2016 profit forecast.
Hess rose 4.9 percent to $68.83. The oil and natural gas producer said it would sell half of its Bakken midstream assets to a private equity firm for $2.68 billion.
After the bell, shares of Twitter rose 5.6 percent as it said CEO Dick Costolo is stepping down. Costolo was under pressure from investors frustrated by the Internet company's slow growth and management shakeups.
Advancing issues outnumbered declining ones on the NYSE by 1,866 to 1,204, for a 1.55-to-1 ratio on the upside; on the Nasdaq, 1,403 issues rose and 1,348 fell for a 1.04-to-1 ratio favoring advancers.
The S&P 500 posted 31 new 52-week highs and two new lows; the Nasdaq recorded 118 new highs and 27 new lows.
About 5.8 billion shares changed hands on U.S. exchanges, below the 6.1 billion daily average for June so far, according to BATS Global Markets. (Additional reporting by Ransdell Pierson; Editing by Meredith Mazzilli, Nick Zieminski and Peter Galloway)