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  <xs:element id="dcth_NotesAndLoansPayableGrossCurrent" abstract="false" name="NotesAndLoansPayableGrossCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_MayTwoThousandAndTwentyTwoEmployeeStockPurchasePlanMember" abstract="true" name="MayTwoThousandAndTwentyTwoEmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_DecemberThirtyFirstTwoThousandTwentyFourMember" abstract="true" name="DecemberThirtyFirstTwoThousandTwentyFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_LoanAgreementRestrictedCash" abstract="false" name="LoanAgreementRestrictedCash" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_DebtInstrumentIncrementalFinalPaymentPercentage" abstract="false" name="DebtInstrumentIncrementalFinalPaymentPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="dcth_MinimumAnnualPayments" abstract="false" name="MinimumAnnualPayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_NumberOfExercisablePreferredWarrants" abstract="false" name="NumberOfExercisablePreferredWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="dcth_TermLoanFromAvenueVentureOpportunitiesFundLpMember" abstract="true" name="TermLoanFromAvenueVentureOpportunitiesFundLpMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_ClassOfWarrantOrRightExercisableWeightedAverageExercisePrice" abstract="false" name="ClassOfWarrantOrRightExercisableWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="dcth_AssumedConversationOfPreferredStockWarrantsMember" abstract="true" name="AssumedConversationOfPreferredStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_DiscountOnNotesAndLoansPayableNoncurrent" abstract="false" name="DiscountOnNotesAndLoansPayableNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_DiscountOnNotesAndLoansPayableCurrent" abstract="false" name="DiscountOnNotesAndLoansPayableCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_LachmanMember" abstract="true" name="LachmanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_SeriesE1PreferredStockMember" abstract="true" name="SeriesE1PreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_PercentageOfFinalPaymentIncludedInGrossAmount" abstract="false" name="PercentageOfFinalPaymentIncludedInGrossAmount" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="dcth_ConvertibleNotePayableRosalindMember" abstract="true" name="ConvertibleNotePayableRosalindMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_OrganizationConsolidationBasisOfPresentationBusinessDescriptionAndAccountingPoliciesTable" abstract="true" name="OrganizationConsolidationBasisOfPresentationBusinessDescriptionAndAccountingPoliciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="dcth_StockOptionCompensationIncomeExpense" abstract="false" name="StockOptionCompensationIncomeExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_DisclosureOfPreferredPurchaseAgreementLineItems" abstract="true" name="DisclosureOfPreferredPurchaseAgreementLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="dcth_TrancheAWarrantsMember" abstract="true" name="TrancheAWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_AssumedConversionOfConvertibleNotesMember" abstract="true" name="AssumedConversionOfConvertibleNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_ConditionForTheExtensionOfPeriodOfInterestOnlyPaymentsMember" abstract="true" name="ConditionForTheExtensionOfPeriodOfInterestOnlyPaymentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_PreferredWarrantLiabilitiesMember" abstract="true" name="PreferredWarrantLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_ContingentLiabilityFairValueDisclosure" abstract="false" name="ContingentLiabilityFairValueDisclosure" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_ThirdPartySettlementMember" abstract="true" name="ThirdPartySettlementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_StockholdersEquityNoteTable" abstract="true" name="StockholdersEquityNoteTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="dcth_RangeOfExercisePricesTenPointZeroRangeMember" abstract="true" name="RangeOfExercisePricesTenPointZeroRangeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_AgreementDomain" abstract="true" name="AgreementDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_ClassOfWarrantOrRightExercisable" abstract="false" name="ClassOfWarrantOrRightExercisable" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="dcth_IssuanceOfCommonStockInPrivatePlacement" abstract="false" name="IssuanceOfCommonStockInPrivatePlacement" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_ClassOfWarrantOrRightWeightedAverageExercisePriceExercised" abstract="false" name="ClassOfWarrantOrRightWeightedAverageExercisePriceExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="dcth_FinalPayment" abstract="false" name="FinalPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_NotesAndLoansPayableGrossNonCurrent" abstract="false" name="NotesAndLoansPayableGrossNonCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_ConversionOfTemporaryEquityToPreferredShares" abstract="false" name="ConversionOfTemporaryEquityToPreferredShares" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_WarrantsIssuedToPurchaseOfCommonStock" abstract="false" name="WarrantsIssuedToPurchaseOfCommonStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="dcth_AmortizationOfRightOfUseAssets" abstract="false" name="AmortizationOfRightOfUseAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_PreferredTrancheAWarrantMember" abstract="true" name="PreferredTrancheAWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_NumberOfSharesPreFundedPennyWarrantsOutstanding" abstract="false" name="NumberOfSharesPreFundedPennyWarrantsOutstanding" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="dcth_SeriesF4PreferredStockMember" abstract="true" name="SeriesF4PreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_ScheduleOfInformationRelatedToStockWarrantsOutstandingAndExercisableTableTextBlock" abstract="false" name="ScheduleOfInformationRelatedToStockWarrantsOutstandingAndExercisableTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="dcth_PercentageOfExciseTaxOnRepurchasesOfStock" abstract="false" name="PercentageOfExciseTaxOnRepurchasesOfStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="dcth_PreferredStockSharesDesignated" abstract="false" name="PreferredStockSharesDesignated" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="dcth_CorporateAlternativeMinimumTax" abstract="false" name="CorporateAlternativeMinimumTax" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="dcth_DetailsAxis" abstract="true" name="DetailsAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="dcth_ControlledEquityOfferingSalesAgreementMember" abstract="true" name="ControlledEquityOfferingSalesAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_NumberOfCommonSharesRemainedAvailableToBeIssued" abstract="false" name="NumberOfCommonSharesRemainedAvailableToBeIssued" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="dcth_CommonStockWarrantsMember" abstract="true" name="CommonStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_ContingentLiabilitiesMember" abstract="true" name="ContingentLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_EstimatedMinimumProceedsOnIssueOfCommonStockForExtensionOfDueDateOfInterestOnlyInterestPayments" abstract="false" name="EstimatedMinimumProceedsOnIssueOfCommonStockForExtensionOfDueDateOfInterestOnlyInterestPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_PreferredTrancheBWarrantMember" abstract="true" name="PreferredTrancheBWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_TermOverWhichTheRoyaltyIsToBePaid" abstract="false" name="TermOverWhichTheRoyaltyIsToBePaid" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="dcth_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="dcth_PrepaidExpensesAndOtherCurrentAssetsTextBlock" abstract="false" name="PrepaidExpensesAndOtherCurrentAssetsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="dcth_SeriesF2PreferredStockMember" abstract="true" name="SeriesF2PreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_PrepaidClinicalTrialExpensesCurrent" abstract="false" name="PrepaidClinicalTrialExpensesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_MinimumAccountingProfitRequiredForPrecedingThreeFinancialYear" abstract="false" name="MinimumAccountingProfitRequiredForPrecedingThreeFinancialYear" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_TrancheLoanFundedIntoRestrictedAccount" abstract="false" name="TrancheLoanFundedIntoRestrictedAccount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_InitialTrancheOfLoan" abstract="false" name="InitialTrancheOfLoan" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_DiscountOnNotesAndLoansPayable" abstract="false" name="DiscountOnNotesAndLoansPayable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="dcth_AccruedExpensesMember" abstract="true" name="AccruedExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_DetailsDomain" abstract="true" name="DetailsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_AssumedConversionOfPreferredStockMember" abstract="true" name="AssumedConversionOfPreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="dcth_WeightedAverageNumberOfSharesPreFundedWarrants" abstract="false" name="WeightedAverageNumberOfSharesPreFundedWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="dcth_NotesAndLoansPayableGross" abstract="false" name="NotesAndLoansPayableGross" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
