Reduced Dose Radiotherapy for the Treatment of Indolent Non-Hodgkin Lymphoma
Indolent B-Cell Non-Hodgkin Lymphoma · Recurrent Indolent B-Cell Non-Hodgkin Lymphoma · Refractory Indolent B-Cell Non-Hodgkin Lymphoma · Recurrent Indolent Non-Hodgkin Lymphoma · Refractory Indolent Non-Hodgkin Lymphoma
What this study involves
The registry says this study is recruiting. Individual locations may have different availability.
- Study type
- Interventional
- Phase
- Phase 2
- Age range
- 18 years - Not specified
- Sex eligible
- All sexes
- Healthy volunteers
- Not accepted
- Participants
- 112 Estimated
These are starting points, not an eligibility decision. The research team must review the full requirements.
About the research
This phase II trial compares the safety, side effects and effectiveness of reduced dose radiation therapy to standard of care dose radiation in treating patients with indolent non-Hodgkin lymphoma. Radiation therapy uses high energy x-rays, particles, or radioactive seeds to kill cancer cells and shrink tumors. Standard of care radiation treatment for indolent non-Hodgkin lymphoma is usually delivered in 12 treatments. Studies have shown indolent lymphoma to be sensitive to radiation treatment, however, larger doses have higher rates of toxicities. A reduced radiation dose may be safe, tolerable and/or effective compared to standard of care radiation dose in treating patients with indolent non-Hodgkin lymphoma.
Read the full description
PRIMARY OBJECTIVE:
I. To show that the experimental arm \[9 gray (Gy) in 3 fractions, 8 Gy in 2 fractions, or 10 Gy in 5 fractions\] has significantly reduced acute toxicity (grade ≥ 2 adverse events at least possibly related to radiation treatment within 14 days after the end of radiation treatment \[according to Common Terminology Criteria for Adverse Events (CTCAE) version (v)5.0\] compared to 24 Gy in 12 fractions.
SECONDARY OBJECTIVES:
I. To evaluate patient reported quality of life. II. To evaluate response rate. III. To evaluate local control rate. IV. To evaluate relapse-free survival.
EXPLORATORY OBJECTIVES:
I. Financial toxicity will be assessed at the end of radiation treatment. II. Financial health care expenditure will be assessed at the end of radiation treatment III. Late toxicity.
CORRELATIVE RESEARCH OBJECTIVES:
I. Biopsies of enrolled patients will be evaluated for pathological assessment of cellular and genetic mutations to correlate them with disease local relapse and radiation resistance.
II. Patients will have their baseline positron emission tomography (PET)/computed tomography (CT) scan undergo auto-segmentation to calculate the functional imaging 18-fluoro-deoxyglucose (FDG) metabolic tumor volume (MTV), total lesions glycolysis (TLG) and maximum standardized uptake volume (SUVmax) of the sites to be treated with involved-site radiation therapy (ISRT) using MIMvista platform to correlate it with disease local relapse and treatment response.
OUTLINE: Patients are randomized to 1 of 2 arms.
ARM I: Patients undergo reduced dose ISRT once daily (QD) over 3, 2, or 5 treatment fractions. Patients also undergo CT or PET/CT throughout the study. Patients may additionally undergo endoscopy during screening and during follow up.
ARM II: Patients undergo standard of care (SOC) radiation therapy QD over 12 treatment fractions. Patients also undergo CT or PET/CT throughout the study. Patients may additionally undergo endoscopy during screening and during follow up.
After completion of study treatment, patients are followed up at days 7 and 14, months 3 and 6, and then every 6 months for up to 2 years post-radiation therapy.
Who may be able to participate?
The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.
Inclusion Criteria:
- Age ≥ 18 years
- Histological confirmation of indolent B-cell lymphoma that can include any of the following:
- Follicular lymphoma (grade 1 or 2 or 3A)
- Marginal zone lymphoma (nodal or extranodal)
- Follicle center lymphoma
- Any stage disease
- Initial, refractory, or relapsed disease. If relapse involves the site to be treated there must be evidence of disease progression
- Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≤ 3
- Negative pregnancy test done ≤ 7 days prior to registration, for persons of childbearing potential only
- Provide written informed consent
- Ability to complete questionnaire(s) by themselves or with assistance
- Willing to return to enrolling institution for follow-up visits (during the active monitoring phase of the study). Virtual visits can also be considered as an option for applicable items
- Confirmation from radiation oncologist of suitability to participate in study
Exclusion Criteria:
- Any of the following:
- Pregnant women
- Nursing women
- Women of childbearing potential who are unwilling to employ adequate contraception
- T-cell lymphoma
- Receiving treatment for small and chronic lymphocytic lymphoma
- Grade 3B follicular lymphoma
Treatment, groups and participation
The registry may describe treatments and study duration without a complete visit calendar. Ask the study team for the exact schedule, procedures, risks, costs and alternatives. Keep your usual care plan unless your treating clinician tells you otherwise.
- Assignment
- Random assignment
- Masking
- No masking
ARM 1 (reduced dose ISRT)
Patients undergo reduced dose ISRT once daily (excluding weekends): 9 Gy delivered in 3 treatment fractions or 8 Gy in 2 fractions. At physician discretion, patients may receive 10 Gy in 5 fractions. Patients also undergo CT or PET/CT throughout the study. Patients may additionally undergo endoscopy during screening and during follow up.
Procedure: Computed Tomography · Procedure: Endoscopic Procedure · Radiation: Involved-site Radiation Therapy (3 Fractions) · Procedure: Positron Emission Tomography · Other: Questionnaire Administration
ARM 2 (SOC ISRT)
Patients undergo standard of care (SOC) radiation therapy once daily (excluding weekends): 24 Gy in 12 treatment fractions. Patients also undergo CT or PET/CT throughout the study. Patients may additionally undergo endoscopy during screening and during follow up.
Procedure: Computed Tomography · Procedure: Endoscopic Procedure · Radiation: Involved-site Radiation Therapy (12 Fractions) · Procedure: Positron Emission Tomography · Other: Questionnaire Administration
Computed Tomography PROCEDURE
Undergo CT or PET/CT
Endoscopic Procedure PROCEDURE
Undergo endoscopy
Involved-site Radiation Therapy (3 Fractions) RADIATION
Undergo ISRT in 3 fractions
Involved-site Radiation Therapy (12 Fractions) RADIATION
Undergo ISRT in 12 fractions
Positron Emission Tomography PROCEDURE
Undergo PET/CT
Questionnaire Administration OTHER
Ancillary studies
What researchers are measuring
Outcome measures describe what is being studied. They are not proof that a treatment works.
Primary measures
Incidence of grade 2 or higher acute adverse events (AEs)
Time frame: Up to 14 days after radiation treatment
AEs will be graded using Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Acute toxicity will be reported as a proportion calculated as the number of patients with acute toxicity divided by the total number of treatment patients. Treatment cycles are 5 days ±2 days (Arm 1) and 16 days ±2 days (Arm 2).
Secondary measures
Response rate
Time frame: Up to 3 months after radiation treatment
Response rate will be defined as the proportion of patients displaying response (complete response or partial response) at 3 months post treatment. Complete response is defined as the disappearance of all signs of cancer in response to treatment. Partial response is defined decrease in the size of target lesions by ≥ 50%, with no increase in the size of any lesion and no appearance of new lesions. Treated patients who do not have a 3-month evaluation will be classified as a non-response. Treatment cycles are 5 days ±2 days (Arm 1) and 16 days ±2 days (Arm 2).
Time to progression rate
Time frame: Up to 24 months after radiation treatment
Local control will be defined as the number of days from end of radiation treatment until first local recurrence within 24 months post radiation treatment. Treatment cycles are 5 days ±2 days (Arm 1) and 16 days ±2 days (Arm 2).
Patient reported quality of life
Time frame: Up to 3 months after radiation treatment
Patient reported quality of life will be measured using Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) scale, a 13-item questionnaire answered on a scale of 1-5 where 1=Not at all and 5=Very much. Treatment cycles are 5 days ±2 days (Arm 1) and 16 days ±2 days (Arm 2).
Review the complete result tables and limitations in the official record.
Open official results ↗Research locations (7)
The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.
7 locations
Mayo Clinic in ArizonaScottsdale, Arizona, United StatesRecruiting
Mayo Clinic in FloridaJacksonville, Florida, United StatesRecruiting
Mayo Clinic Health System in Albert LeaAlbert Lea, Minnesota, United StatesRecruiting
Mayo Clinic Health System - MankatoMankato, Minnesota, United StatesWithdrawn
Mayo Clinic in RochesterRochester, Minnesota, United StatesRecruiting
Mayo Clinic Health System-Eau Claire ClinicEau Claire, Wisconsin, United StatesRecruiting
Mayo Clinic Health System-Franciscan HealthcareLa Crosse, Wisconsin, United StatesRecruiting
Study team and timeline
- Lead sponsor
- Mayo Clinic
- Study start
- May 15, 2024 Actual
- Primary completion
- May 30, 2029 Estimated
- Study completion
- May 30, 2031 Estimated
- First posted
- Apr 26, 2024 Actual
- Last updated
- Nov 10, 2026 Actual
Official study contacts
Official study title
MC230808 Reduced Dose Hypofractionated Radiotherapy (3Gy x 3 Fractions) for Indolent Non-Hodgkin Lymphoma (POSEIDON): A Multisite Phase 2 Randomized Trial
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Source: ClinicalTrials.gov API v2. Information is submitted by sponsors and investigators. NLM does not approve the safety or science of all listed studies. Registry disclaimer.
Retrieved: Nov 12, 2026 · Last registry update: Nov 10, 2026