SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

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                                    FORM 8-K

                                 CURRENT REPORT

                     PURSUANT TO SECTION 13 OR 15(D) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

        Date of report (Date of earliest event reported): July 15, 2003
                                                          -------------

                               CYTOGEN CORPORATION
              -----------------------------------------------------
               (Exact Name of Registrant as Specified in Charter)

          Delaware                       000-14879                222322400
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(State or Other Jurisdiction     (Commission File Number)     (I.R.S. Employer
      of Incorporation)                                      Identification No.)

650 College Road East, CN 5308, Suite 3100, Princeton, NJ             08540
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        (Address of Principal Executive Offices)                    (Zip Code)

       Registrant's telephone number, including area code: (609) 750-8200
                                                           --------------





ITEM 5.      OTHER EVENTS AND REQUIRED FD DISCLOSURE.

            On July 15, 2003,  Advanced Magnetics,  Inc. ("Advanced  Magnetics")
and  Cytogen  Corporation   ("Cytogen")  announced,  in  a  press  release,  the
presentation  of  data  showing  that  magnetic  resonance  imaging  (MRI)  with
Combidex(R) (ferumoxtran-10),  an investigational iron oxide nanoparticle,  aids
in the non-invasive  diagnosis of metastatic lymph nodes. The data was presented
by Dr. Mukesh  Harisinghani,  Assistant  Radiologist  at  Massachusetts  General
Hospital and Dr. Ralph Weissleder,  Director of the Center for Molecular Imaging
Research at Massachusetts  General Hospital,  at the  International  Society for
Magnetic  Resonance in Medicine (ISMRM) 11th Scientific Meeting held in Toronto,
July 10-16,  2003,  and was from a study that included  patients with breast and
prostate  cancer.  Cytogen has a license with  Advanced  Magnetics for exclusive
marketing rights to Combidex(R) in the United States.

            Such  press  release  is  attached  hereto  as  Exhibit  99.1 and is
incorporated  herein by  reference.  The  foregoing  description  of such  press
release is qualified in its entirety by reference to such document.


ITEM 7.      FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS.

     (c)     Exhibits.

                Exhibit No.    Description
                -----------    ------------

                    99.1       Press release of the Company dated July 15, 2003.





                                   SIGNATURES



         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
the  Registrant  has duly caused this current report on Form 8-K to be signed on
its behalf by the undersigned hereunto duly authorized.

                                      CYTOGEN CORPORATION


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

Dated:   July 15, 2003






                                  EXHIBIT INDEX


             Exhibit No.      Description
             -----------      -----------

                99.1          Press release of the Company dated July 15, 2003.