<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-04-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000872912</issuerCik>
        <issuerName>DELCATH SYSTEMS INC</issuerName>
        <issuerTradingSymbol>DCTH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001266152</rptOwnerCik>
            <rptOwnerName>LADD ROBERT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O LADDCAP VALUE ADVISORS LLC</rptOwnerStreet1>
            <rptOwnerStreet2>650 FIFTH AVENUE, SUITE 600</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock, $0.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2006-04-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>900</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.91</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1930100</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By limited partnership</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Laddcap Value Partners LP, a Delaware limited partnership (&quot;Laddcap&quot;), is the record holder of 1,930,100 shares of the common stock $0.01 par value per share (the &quot;Shares&quot;), of Delcath Systems, Inc. (the &quot;Company&quot;).  Robert Ladd possesses the sole power to vote and the sole power to direct the disposition of all the Company's Shares held by Laddcap.  Thus, as of April 6, 2006, for the purposes of Reg. Section 240.13d-3, Mr. Ladd is deemed to beneficially own 1,930,100 Shares.  Mr. Ladd's interest in the Shares reported herein is limited to the extent of his pecuniary interest, if any, in Laddcap.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Robert Ladd</signatureName>
        <signatureDate>2006-04-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
