How to make a function wait until a function return a value using node.js

This code return an error before executing the "sendTransaction" function. I have used a callback but it doesn't work also. Any help please ! here is the code that I have written

var mytoken= MyContract.at(contractAddress);    
router.get('/test',function (req, res, next)
 {
   res.render('test.ejs');
 });
  //send token
  router.post('/test', function(req, res, next) {
  var recieverAdd = req.body.to;
  var from=req.body.from;
  var amount = req.body.amount;
  var bool= web3.personal.unlockAccount(web3.eth.accounts[0],"yosra");   

  mytoken.transfer.sendTransaction(from,recieverAdd,amount, {from:eth.accounts[0],gas:500000},function (error, result)
    {
        callback(result);

    });
 });

via takampika