This was a hard room, I agree, but there are one or two things you can do to manipulate roaches, which will make it easier.
First...
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×...on orthogonal squares, you are only vulnerable in orthogonal directions - if you're getting swamped, head for corners or areas that protect those squares, but don't worry about squares on a diagonal from you.
Also...
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×...have you noticed that roaches seem to prefer vertical movement over horizontal? Watch for roaches attacking areas to the left or right of you - they'll move into the same row as you before moving horizontally towards you.
Being bold, like Oneiromancer said, is also helpful since...
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×...unlike with normal squares, as long as you don't expose two or more squares in orthogonal directions, you should be perfectly safe. You can exploit this by moving right to the edge of a 1-square wide passage. Although you will have 2-3 roaches right next to you, only one of those can actually attack you.
For this room in particular...
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×The nastiest bit is moving north after killing the queens in the southwest corner.
You need to use the corners in the wall to the north of the chamber entrance...
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×...specifically the one at (10,22)...
...to help protect you from the roaches coming from the east (the ones to the north are blocked by the wall, so they are not a threat.
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×If you've killed the monsters from the east, attack the ones to the north, staying close to your corner and retreating into it when the eastern group from the next spawning reaches you.
You can repeat this indefinitely (the roach numbers will end up in equilibrium) and you'll find that there will eventually only be about 3 or 4 roaches left to the north after you've cleared out the latest group from the east.
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×When in this situation, quickly head north to (8,17), ignoring any roaches that are not posing any threat to you, and avoiding entering row 16 (or you'll end up with two sets of roaches to deal with, not one. In this position, the square at (8,15) will stop the roaches from the north from reaching you, leaving you free to deal with the rest of the ones coming from the east. Once killed, you should then be able to deal with the ones to the west before the next group from the east reaches you.