CYTOGEN CORPORATION
                       650 College Road East, Suite 3100
                        Princeton, New Jersey 08540-5308




December 22, 2006




VIA FACSIMILE & EDGAR
---------------------

Securities and Exchange Commission
Division of Corporation Finance
100 F Street, N.E.
Washington, D.C. 20549
Attention:  Song P. Brandon, Esq.


Re:   Cytogen Corporation
      Registration Statement on Form S-3 Filed on December 18, 2006 (File Number
      --------------------------------------------------------------------------
      333-139264)
      -----------


Dear Ms. Brandon:

     In accordance  with Rule 461 under the  Securities  Act of 1933, as amended
(the "Securities  Act"),  Cytogen  Corporation  (the "Company")  hereby requests
acceleration of the  effectiveness  of the Company's  Registration  Statement on
Form S-3, File Number 333-139264, as amended, relating to the registration under
the  Securities  Act of that  number of shares of its  common  stock,  $0.01 par
value, as is set forth in such Registration Statement, for December 26, 2006, at
4:00 p.m. New York City time, or as soon as practicable thereafter.

     This letter will confirm that the Company acknowledges that:

     o   should the Securities and Exchange Commission (the "Commission") or the
         staff, acting  pursuant to the delegated  authority, declare the filing
         effective, it does not foreclose the Commission  from taking any action
         with respect to the filing;
     o   the action of the Commission or the staff, acting pursuant to delegated
         authority,  in declaring the  filing  effective,  does not  relieve the
         Company  from its full responsibility for  the adequacy and accuracy of
         the disclosure  in the  filing;  and
     o   the Company  may not assert this action as a defense in any  proceeding
         initiated by the  Commission or any person under the federal securities
         laws of the United States.





Securities and Exchange Commission
Page 2


     This  letter  will  also   confirm   that  the  Company  is  aware  of  its
responsibilities  under the Securities  Act and the  Securities  Exchange Act of
1934,  as  amended,  as they  relate  to the  proposed  public  offering  of the
securities specified in the above-captioned Registration Statement on Form S-3.


Very truly yours,

CYTOGEN CORPORATION


By: /s/ Michael D. Becker
    -------------------------------------------------
    Name:  Michael D. Becker
    Title:  President and Chief Executive Officer