WOLF, BLOCK, SCHORR AND SOLIS-COHEN LLP
                          1650 Arch Street, 22nd Floor
                           Philadelphia, PA 19103-2097
                                T: (215) 977-2000
                                F: (215) 977-2334
                                www.wolfblock.com



                                December 17, 2001

Cytogen Corporation
600 College Road East CN 5308
Princeton, NJ  08450

RE:  Registration Statement on Form S-8 Relating to the Cytogen Corporation
     Performance Bonus Plan with Stock Payment Program, Effective June 19, 2001

Ladies and Gentlemen:

         As counsel to Cytogen Corporation, a Delaware corporation (the
"Company"), we have assisted in the preparation of the registration statement on
Form S-8 (the "Registration Statement") to be filed with the Securities and
Exchange Commission under the Securities Act of 1933, as amended (the "Act"),
relating to 300,000 shares of the Company's Common Stock, $0.01 par value per
share (the "Common Stock"), which may be issued under the Cytogen Corporation
Performance Bonus Plan with Stock Payment Program, Effective June 19, 2001 (the
"Plan").

         In this connection, we have examined and considered the originals or
copies, certified or otherwise identified to our satisfaction, of the Company's
Restated Certificate of Incorporation, as amended, its Bylaws, as amended, the
Plan, resolutions of the Company's Board of Directors, and such other
certificates, records and documents relating to the Company and the issuance and
sale of the Common Stock covered by the Registration Statement and such matters
of law as we have deemed appropriate for purposes of rendering this opinion.

         In all examinations of documents, instruments and other papers, we have
assumed the genuineness of all signatures on original and certified copies of
documents and the conformity to originals of all documents submitted to us as
conformed, photostat or other copies. As to matters of fact which have not been
independently established, we have relied upon representations of officers of
the Company.

         The 300,000 shares of Common Stock to which the Registration Statement
relates may be issued from time to time on a delayed or continuous basis, and
this opinion is limited to the laws, including applicable rules and regulations,
in effect on the date hereof. We assume no obligation to update this opinion.



         Based on the foregoing examination and information thus supplied, it is
our opinion that the 300,000 shares of Common Stock covered by the Registration
Statement and to be offered under the Plan are duly authorized and, when issued
and sold by the Company pursuant to the terms of the Plan, will be validly
issued, fully paid and nonassessable shares of Common Stock.

         Our examination of law relevant to the matters covered by this opinion
is limited to Delaware law. Accordingly, we express no opinions as to matters
governed by the laws of any other state or jurisdiction.

         We hereby consent to the filing of this opinion as Exhibit 5 to the
Registration Statement. In giving this opinion, we do not thereby admit that we
are acting within the category of persons whose consent is required under
Section 7 of the Act or the rules or regulations of the Securities and Exchange
Commission thereunder.

                                Very truly yours,



                   /s/ Wolf, Block, Schorr and Solis-Cohen LLP




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