Page CTR,
CTR stands for "click through rate". it's expressed as a percantage of the page impressions that resulted in somebody clicking one of the AdSense ads. So, for example, if you had 1,000 page impressions, and those 1,000 page impressions resulted in 100 clicks on the ads, that is a 10% Page CTR (100/1000=10%).

Page eCMP,

eCMP stands for "effective cost per millie". "Millie" means thousand. CPM is what the old world of banner advertisements used in pricing their ads. If a site had a $10 CMP, that meant that you as an advertiser would pay $10 for every 1,000 page impressions that your ad was shown on.

With AdSense, eCPM is telling you how much you are earning (or will earn), on average, for every 1,000 page impressions. If you have a $25 eCPM, that means you are earning (or will earn) $25 in clicks for every 1,000 page impressions on your site.

Google shows you this figure so you can get an idea of how much more they are paying you than a banner advertising network will pay you.

EPC

You won't see the term EPC in your Google AdSense reports, but you'll hear it a lot if you hang out on AdSense forums. EPC stands for "earnings per click", and just means how much earn for each click.