I've run into several instances where I needed to store HTML in a table. The problem is sometimes the HTML references APEX Items. For example if your HTML needs to reference a picture, odds are you'll need to reference &APP_IMAGES. (or some image location item). In the past I've done manual REPLACE calls for known items, but it was fairly restrictive.

APEX has a great function (not yet documented to my knowledge) called APEX_APPLICATION.DO_SUBSTITUTIONS. If you pass in a string, it will substitute any APEX values. Here's an example app: http://apex.oracle.com/pls/otn/f?p=20195:2000

To create demo:

1- Create table and insert values

CREATE TABLE tp2000(line_content CLOB NOT NULL);

INSERT INTO tp2000
     VALUES ('Google Canada Picture: ![]()');

INSERT INTO tp2000
     VALUES ('My Current Session: ' || CHR (38) || 'APP_SESSION.');

2- Create Report Region (with substitutions)

SELECT apex_application.do_substitutions (line_content) content_with_subs
  FROM tp2000

3- Create Report Region (without substitutions)

SELECT line_content content_without_subs
  FROM tp2000