Trend Micros System Cleaner or Sysclean is an emergency scanner and remover from Trend Micro. It can be used in such cases when PC is heavily infected and it is impossible to instal full antivirus or internet security suite. Like most of Emergency scanners, it is a portable app, that can be run from USB drive.
The instalation file of Trend Micro Sysclean is 400 KB only, however it will have to download around 100 mb of parasite definitions and required files prior the scan. This can be done on uninfected PC as the definitions are stored in the same folder with executables. The System Cleaner scanning itself should be launched from Safe mode with networking (if you wish to update program) or from Safe mode. You can move its files using USB drive or CD, and you do not need to install anything on infected PC.
Trend Micro System cleaner is quite throughful and will scan all files. There is no quick scan mode easily accessible. Thus the scan will take some time. You can choose between automatic cleanup of infected files or SysClean will prompt for performing this action.
Overall SysClean is decent emergency scanner, however it has several drawbacks. First of all, it has limited applicability: you should use it on infected PCs that can still be booted to Safe mode with networking without malware interfering with executing removal programs. In such cases I would use one of the (multi-engine) cloud scanner programs (if bandwidth is not a problem) or Bootable scanners (if bandwidth is a problem). Due to full system scan it is not applicable for second-opinion system scans as well (it takes a bit too long).
Would I use TrendMicro SysClean ? Yes, I would bring it in usb drive to clean infected PCs, but it will not be one of the first tools to try. A decent guide how to use it available on TrendMicro page here : http://esupport.trendmicro.com/Pages/How-do-I-use-the-Trend-Micro-System-Cleaner.aspx