mangled packages

[Art Edwards]

While doing a routine dist-upgrade, I found that several packages were mangled. 
I'm running 12.04 on a dual-core, amd, 64 bit machine. Here is a typical error:

dpkg: warning: parsing file '/var/lib/dpkg/available' near line 37548 package 'liblcms2-2:amd64':
 missing description
dpkg: error: parsing file '/var/lib/dpkg/available' near line 37548:
 field name `' must be followed by colon
E: Sub-process /usr/bin/dpkg returned an error code (2)
A package failed to install.  Trying to recover:

This particular package is used by many others. I would appreciate any 
suggestions

Art Edwards