Christin A. Knowlton, MD, MA
Associate Professor of Therapeutic RadiologyCards
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Vice Chair for Accreditation, Therapeutic Radiology
Medical Director, Smilow Cancer Hospital Care Center-Hamden, Therapeutic Radiology
Chief, Breast Radiotherapy Program, Therapeutic Radiology
Contact Info
Therapeutic Radiology
PO Box 208040
New Haven, CT 06520-8040
United States
Are You a Patient?
View this doctor's clinical profile on the Yale Medicine website for information about the services we offer and making an appointment.
View Doctor ProfileAdditional Titles
Vice Chair for Accreditation, Therapeutic Radiology
Medical Director, Smilow Cancer Hospital Care Center-Hamden, Therapeutic Radiology
Chief, Breast Radiotherapy Program, Therapeutic Radiology
Contact Info
Therapeutic Radiology
PO Box 208040
New Haven, CT 06520-8040
United States
Are You a Patient?
View this doctor's clinical profile on the Yale Medicine website for information about the services we offer and making an appointment.
View Doctor ProfileAdditional Titles
Vice Chair for Accreditation, Therapeutic Radiology
Medical Director, Smilow Cancer Hospital Care Center-Hamden, Therapeutic Radiology
Chief, Breast Radiotherapy Program, Therapeutic Radiology
Contact Info
Therapeutic Radiology
PO Box 208040
New Haven, CT 06520-8040
United States
About
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Titles
Associate Professor of Therapeutic Radiology
Vice Chair for Accreditation, Therapeutic Radiology; Medical Director, Smilow Cancer Hospital Care Center-Hamden, Therapeutic Radiology; Chief, Breast Radiotherapy Program, Therapeutic Radiology
Biography
Dr. Christin Knowlton provides expertise in breast cancer radiation oncology and high-quality patient centered care in Hamden. She specializes in radiation therapy for breast cancer, lung cancer, bone metastases, and thymoma and says she was drawn to her field because it provides the opportunity to treat cancer often with tangible results. Dr. Knowlton says the best part of her job is meeting patients and answering questions about their disease process and treatment options. She received her medical degree from SUNY at Stonybrook. In 2019 she received the Smilow Luminary Award of Excellence in Patient Care.
Appointments
Therapeutic Radiology
Associate Professor on TermPrimary
Other Departments & Organizations
Education & Training
- Residency
- Hahnemann University Hospital/Drexel University College of Medicine (2011)
- MD
- SUNY at Stonybrook (2006)
- MA
- New York University, Education (1998)
- BA
- Oberlin College (1994)
Research
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Overview
Medical Research Interests
Research at a Glance
Yale Co-Authors
Publications Timeline
Research Interests
Henry S. Park, MD, MPH
Allison Campbell, MD, PhD
Nadine Housri, MD
Thomas Hayman, MD, PhD
Anne Chiang, MD, PhD
Daniel Hicks, MD
Breast Neoplasms
Publications
2026
Consolidative Radiotherapy for Extensive-Stage Small Cell Lung Cancer: Outcomes Based on Completeness of Consolidation and Oligometastatic State
Ninia JG, Verma N, Long JB, Laird JH, Hicks DF, Hayman TJ, Knowlton CA, Campbell AM, Housri N, Peters GW, Al Feghali KA, de Jong D, Chiang AC, Park HS. Consolidative Radiotherapy for Extensive-Stage Small Cell Lung Cancer: Outcomes Based on Completeness of Consolidation and Oligometastatic State. Clinical Lung Cancer 2026, 27 DOI: 10.1016/j.cllc.2026.03.009.Peer-Reviewed Original ResearchConsolidative Radiotherapy for Extensive-Stage Small Cell Lung Cancer: Outcomes Based on Completeness of Consolidation and Oligometastatic State
Ninia J, Verma N, Long J, Laird J, Hicks D, Hayman T, Knowlton C, Campbell A, Housri N, Peters G, Al Feghali K, de Jong D, Chiang A, Park H. Consolidative Radiotherapy for Extensive-Stage Small Cell Lung Cancer: Outcomes Based on Completeness of Consolidation and Oligometastatic State. Clinical Lung Cancer 2026, 27: 14-23. PMID: 42019269, DOI: 10.1016/j.cllc.2026.03.009.Peer-Reviewed Original ResearchAltmetricMeSH Keywords and ConceptsConceptsExtensive-stage small cell lung cancerProgression-free survivalSmall cell lung cancerOverall survivalCell lung cancerMetastatic stateConsolidation radiotherapyOligometastatic statusRestricted mean survival timeExtensive-stage small cell lung cancer patientsLung cancerProgression-free survival gainFirst-line systemic therapyEastern Cooperative Oncology Group statusTarget residual diseaseMedian Follow-UpLog-rank testRetrospective cohort studyMean survival timeImmunotherapy receiptOligometastatic stateOligometastatic patientsResidual diseaseRT completionSystemic therapy
2025
Percutaneous Cryoablation of Non-small Cell Lung Cancer in Patients with Recurrence After Stereotactic Body Radiation Therapy
Fish A, Park H, Knight E, Knowlton C, Madoff D. Percutaneous Cryoablation of Non-small Cell Lung Cancer in Patients with Recurrence After Stereotactic Body Radiation Therapy. CardioVascular And Interventional Radiology 2025, 48: 626-632. PMID: 40069339, DOI: 10.1007/s00270-025-04002-0.Peer-Reviewed Original ResearchCitationsAltmetricMeSH Keywords and ConceptsConceptsStereotactic body radiation therapyNon-small cell lung cancerCell lung cancerProgression-free survivalLung cancerPercutaneous cryoablationRadiation therapyOverall survivalTechnical successLocal controlNon-small cell lung cancer recurrenceHome oxygen requirementPost-procedure hospitalizationHistory of smokingWorsening pulmonary functionPost-procedural pneumothoraxEffective treatment alternativeConclusionPercutaneous cryoablationCryoablation protocolResults29 patientsTarget tumorsAdverse eventsCryoablationPulmonary functionLesion sizeModern-Day Hypofractionated Postmastectomy Radiation
Rybkin A, Bodofsky S, Knowlton C. Modern-Day Hypofractionated Postmastectomy Radiation. Current Breast Cancer Reports 2025, 17: 7. DOI: 10.1007/s12609-025-00570-9.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsPostmastectomy radiationBreast cancerPost-mastectomy settingRegional nodal irradiationRadiobiological dataQuality of life metricsNodal irradiationBreast conservationEradicate tumorsComplication rateBrachial plexopathyPostmastectomy patientsToxicity profileHypofractionationFractionation schemaTherapeutic windowReviewThis reviewTissue effectsTrial dataBreastPostmastectomyStandard optionDisease controlPatientsCancer
2024
Radioresistant Pulmonary Oligometastatic and Oligoprogressive Lesions From Nonlung Primaries: Impact of Histology and Dose-Fractionation on Local Control After Radiation Therapy
Verma N, Laird J, Moore N, Hayman T, Housri N, Peters G, Knowlton C, Jairam V, Campbell A, Park H. Radioresistant Pulmonary Oligometastatic and Oligoprogressive Lesions From Nonlung Primaries: Impact of Histology and Dose-Fractionation on Local Control After Radiation Therapy. Advances In Radiation Oncology 2024, 9: 101500. PMID: 38699671, PMCID: PMC11063223, DOI: 10.1016/j.adro.2024.101500.Peer-Reviewed Original ResearchCitationsAltmetricConceptsLocal recurrence-free survivalNon-lung primaryAssociated with higher local recurrence-free survivalProgression-free survivalBiologically Effective DoseLocal controlRadioresistant metastasesOverall survivalPulmonary metastasesPrimary cancerColorectal carcinomaAssociated with superior local controlMultivariate analysisPatients treated with radiotherapyRisk of local recurrenceMedian follow-up timeMultivariable Cox proportional hazards regressionInferior local controlMedian total doseSuperior local controlAssociated with decreased riskImpact of histologyMetastasis-free survivalRecurrence-free survivalLocal failure
2023
Dose-Volume Predictors of Radiation Pneumonitis After Thoracic Hypofractionated Radiation Therapy
Sasse A, Oh P, Saeed N, Yang D, Hayman T, Knowlton C, Peters G, Campbell A, Laird J, Housri N, Park H. Dose-Volume Predictors of Radiation Pneumonitis After Thoracic Hypofractionated Radiation Therapy. Practical Radiation Oncology 2023, 14: e97-e104. PMID: 37984711, DOI: 10.1016/j.prro.2023.11.006.Peer-Reviewed Original ResearchCitationsAltmetricConceptsMean lung doseHypofractionated radiation therapyRisk of gradeRadiation pneumonitisLung V20Lung V5Dose-volume predictorsDosimetric risk factorsLogistic regression analysisGrade 5 casesSingle healthcare systemPrimary endpointDose regimensMultivariable analysisLung doseThoracic tumorsDosimetric variablesRisk factorsPneumonitisRadiation therapyCommon treatmentClinical practicePatientsSignificant associationPotential predictorsBilateral Breast Cancer With Contralateral Axillary Metastasis Warrants Aggressive Treatment: Let's Go for It!
Mokhtech M, Knowlton C. Bilateral Breast Cancer With Contralateral Axillary Metastasis Warrants Aggressive Treatment: Let's Go for It! International Journal Of Radiation Oncology • Biology • Physics 2023, 117: 527-528. PMID: 37739602, DOI: 10.1016/j.ijrobp.2023.03.039.Commentaries, Editorials and LettersMeSH Keywords and Concepts
2022
Risk Assessment in the Molecular Era
Knowlton CA, Jimenez RB, Moran MS. Risk Assessment in the Molecular Era. Seminars In Radiation Oncology 2022, 32: 189-197. PMID: 35688517, DOI: 10.1016/j.semradonc.2022.01.005.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsCitationsAltmetricMeSH Keywords and ConceptsConceptsBreast-conserving surgeryClinical-pathologic featuresHormone receptor-positive diseaseLow-risk DCIS patientsLow-risk DCISAdjuvant endocrine therapyLocal control rateMajority of patientsSpecific survival outcomesPersonalized risk assessmentMolecular assaysBreast recurrenceDCIS patientsDCIS ScoreRT recommendationsDefinitive surgeryEndocrine therapyPostoperative radiotherapyPositive diseaseDuctal carcinomaSurvival outcomesControl rateInvasive cancerTreatment paradigmBreast cancer
2021
Benefit of Deep Inspiratory Breath Hold for Right Breast Cancer When Regional Lymph Nodes Are Irradiated
Peters GW, Gao SJ, Knowlton C, Zhang A, Evans SB, Higgins S, Wilson LD, Saltmarsh N, Picone M, Moran MS. Benefit of Deep Inspiratory Breath Hold for Right Breast Cancer When Regional Lymph Nodes Are Irradiated. Practical Radiation Oncology 2021, 12: e7-e12. PMID: 34508890, DOI: 10.1016/j.prro.2021.08.010.Peer-Reviewed Original ResearchCitationsAltmetricMeSH Keywords and ConceptsConceptsRight-sided breast cancerRegional nodal irradiationLiver VBreast cancerLung VDIBH plansLiver parametersLung doseComprehensive regional nodal irradiationLeft-sided breast cancerRight breast cancerWilcoxon signed-rank testingRegional lymph nodesTotal liver volumeIpsilateral lung VLiver DHeart VNodal irradiationRBC patientsHeart doseLymph nodesInspiratory breathLiver volumeLarge cohortTreatment planOptimal Management for Residual Disease Following Neoadjuvant Systemic Therapy
Foldi J, Rozenblit M, Park TS, Knowlton CA, Golshan M, Moran M, Pusztai L. Optimal Management for Residual Disease Following Neoadjuvant Systemic Therapy. Current Treatment Options In Oncology 2021, 22: 79. PMID: 34213636, DOI: 10.1007/s11864-021-00879-4.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsCitationsAltmetricMeSH Keywords and ConceptsConceptsPathologic complete responseResidual cancerClinical trialsAdjuvant therapyExcellent long-term disease-free survivalLong-term disease-free survivalAxillary lymph node dissectionHuman epidermal growth factor receptor 2Early-stage breast cancerEpidermal growth factor receptor 2Post-mastectomy breastSystemic adjuvant therapyInternal mammary nodesLymph node dissectionNeoadjuvant systemic therapyDisease-free survivalGrowth factor receptor 2Minimal residual disease monitoringRecurrence-free survivalType of surgeryPivotal clinical trialsOngoing clinical trialsFactor receptor 2Residual disease monitoringAccurate prognostic estimates
Clinical Trials
Current Trials
Phase IB/II Trial Of Dose-Deescalated 3-Fraction Stereotactic Body Radiotherapy For Centrally Located Lung Cancer
IRB ID2000025868RoleSub InvestigatorPrimary Completion Date01/31/2030Recruiting Participants
Academic Achievements & Community Involvement
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Honors
honor Smilow Luminary Award of Excellence: Patient Care
10/18/2019Other AwardSmilow Cancer HospitalDetailsUnited States
Clinical Care
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Overview
Christin Knowlton, MD, is a therapeutic radiologist and is medical director of the Smilow Cancer Care Center in Hamden. Dr. Knowlton specializes in radiation therapy for breast cancer, lung cancer, bone metastases, and thymoma.
Dr. Knowlton says she was drawn to her field because it provides the opportunity to treat cancer “often with tangible results.”
“Radiation therapy is very successful at killing cancer cells and also helping with symptoms such as pain or bleeding from tumors,” she says. “In addition, some courses of radiation therapy span several days to weeks, which allows the physician the opportunity to really get to know the patients and their families.”
In fact, Dr. Knowlton says the best part of her job is meeting patients and answering questions about their disease process and treatment options.
“I also enjoy working closely with the members of the department of radiation oncology, including nursing, physics, dosimetry (treatment planning), and therapy to provide high-quality, patient-centered care,” she adds. “We work as a team to provide the best possible care for each patient.”
Clinical Specialties
Fact Sheets
Radiation Therapy
Learn More on Yale MedicineLung Cancer
Learn More on Yale MedicineBreast Cancer
Learn More on Yale MedicineLung Cancer in Nonsmokers
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Contacts
Therapeutic Radiology
PO Box 208040
New Haven, CT 06520-8040
United States
Administrative Support
Locations
Patient Care Locations
Are You a Patient? View this doctor's clinical profile on the Yale Medicine website for information about the services we offer and making an appointment.