Combine body of request.js calls

Question

I am looking to make a GET call over a few parameters (with request.js) , combine the result and return it as my own GET API (with express.js) - like so:

app.get("myapi", (req. res) => {
  parameters = ["a", "b", "c"]
  let result = {}

  parameters.forEach(param => {
    const uri = `https://api.exampleApi.com/?parameter=${param}`
    request.get(uri, (error, response, body) => {
      result[param] = body.data;
    });
  });
  res.json(result);
});

However, the result returned for this is empty {}. How can I combine multiple calls?

EDIT: Here is my new code with an array of Promises.

app.get("/api/v1/leagues/games", (req, res) => {
  const promiseRequest = (sport, region, mkt) => {
    return new Promise(resolve => {
      const theOddsApiUrl = `https://api.the-odds-api.com/v3/odds/?apiKey=${functions.config().theoddsapi.key}&sport=${sport}&region=${region}&mkt=${mkt}`; 
      request.get(theOddsApiUrl, (error, response, body) => {
        if (body) {
          resolve(body)
        }
      });
    })
  }
  const makeRequest = (sport, mkt) => {
    let allRegionsOdds = {};
    Promise.all([
      promiseRequest(sport, 'uk', mkt),
      promiseRequest(sport, 'us', mkt),
      promiseRequest(sport, 'au', mkt)
    ]).then(body => {
      return allRegionsOdds[region] = body;
    }).catch();
  }
  const response = makeRequest(req.query.sport, req.query.mkt);
  res.json(response);
});