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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 L3kJYfbdPRVkqabKPEJrpA==

<SEC-DOCUMENT>0001140361-07-012409.txt : 20070615
<SEC-HEADER>0001140361-07-012409.hdr.sgml : 20070615
<ACCEPTANCE-DATETIME>20070615132538
ACCESSION NUMBER:		0001140361-07-012409
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070613
FILED AS OF DATE:		20070615
DATE AS OF CHANGE:		20070615

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CYTOGEN CORP
		CENTRAL INDEX KEY:			0000725058
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				222322400
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		650 COLLEGE RD EAST STE 3100
		CITY:			PRINCETON
		STATE:			NJ
		ZIP:			08540
		BUSINESS PHONE:		6099878200

	MAIL ADDRESS:	
		STREET 1:		650 COLLEGE RD EAST STE 3100
		CITY:			PRINCETON
		STATE:			NJ
		ZIP:			08540

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GRIGSBY JAMES A
		CENTRAL INDEX KEY:			0001022842
		STATE OF INCORPORATION:			PA

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14879
		FILM NUMBER:		07922310

	BUSINESS ADDRESS:	
		STREET 1:		CO/CYTOGEN CORPORATION
		STREET 2:		600 COLLEGE ROAD EAST
		CITY:			PRINCETON
		STATE:			NJ
		ZIP:			08540
		BUSINESS PHONE:		8602491410

	MAIL ADDRESS:	
		STREET 1:		CANCER CARE MANAGEMENT
		STREET 2:		750 MAIN ST STE 200
		CITY:			HARTFORD
		STATE:			CT
		ZIP:			06103
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-06-13</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000725058</issuerCik>
        <issuerName>CYTOGEN CORP</issuerName>
        <issuerTradingSymbol>CYTO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001022842</rptOwnerCik>
            <rptOwnerName>GRIGSBY JAMES A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CYTOGEN CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>650 COLLEGE ROAD EAST, STE 3100</rptOwnerStreet2>
            <rptOwnerCity>PRINCETON</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08540</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-06-13</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Options to purchase common stock</value>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-06-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>17500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-06-14</value>
            </exerciseDate>
            <expirationDate>
                <value>2017-06-14</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>17500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Such shares of restricted common stock were issued pursuant to the terms of the Company's 2006 Equity Compensation Plan and vest on one (1) year anniversary.</footnote>
        <footnote id="F2">Such options were granted pursuant to the terms of the Company's 2004 Non-Employee Director Stock Incentive Plan, and vest in full on the one-year anniversary of the date of grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ James A. Grigsby</signatureName>
        <signatureDate>2007-06-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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