[chaley]

Sure. Make a custom column based on other columns. The template would be something like:
{comments:re((?i).*last page read: location \((\d+)\).*,\1)}

This will find the last 'Last Page Read' in comments. If you want to find the first such line, then try:
{comments:re((?i).*?last page read: location \((\d+)\).*,\1)}