Preoperative Sequential Short-course Radiation Therapy and FOLFOX for Locally Advanced Rectal Cancer (SOLAR)

February 10, 2026 updated by: Gyu-Seog Choi, Kyungpook National University Hospital

A Multicenter, Randomized Controlled Trial of Preoperative Sequential Short-course Radiation Therapy and Oxaliplatin-based Consolidation Chemotherapy for Locally Advanced Rectal Cancer

The treatment protocol proposed in this study is to perform short-term radiation therapy and 4 cycles of FOLFOX chemotherapy for neoadjuvant treatment of locally advanced rectal cancer. Compared to conventional chemoradiation therapy, the preoperative radiotherapy period is shortened, and the cure rate of rectal cancer patients can be improved by early treatment of micrometastasis using systemic chemotherapy. The patients who are assigned to the study group will received the short-course radiotherapy and 4 cycles of FOLFOX and patients in the control will received conventional chemoradiotherapy for preoperative treatment. All patients are recommended to receive total mesorectal excision (TME) after neoadjuvant treatment and adjuvant chemotherapy will be given according to the pathological stage.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
364

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • South Korea
      • Daegu, South Korea, 702-210
        • Gyu seog Choi
      • Daejeon, South Korea
        • Chungnam National University Hospital
      • Gwangju, South Korea
        • Chonnam National University Hwasun Hospital
      • Incheon, South Korea
        • Catholic University of Korea Incheon St. Mary's Hospital
      • Jeonju, South Korea
        • Jeonbuk National University Hospital
      • Seoul, South Korea, 05505
        • Asan Medical Center
      • Seoul, South Korea
        • Gangnam Severance Hospital
      • Seoul, South Korea
        • Seoul National University Bundang Hospital
      • Seoul, South Korea
        • , Korea University Anam Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

20 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Asian
  • ECOG (Eastern Cooperative Oncology Group) performance status 0-2
  • Pathologically confirmed rectal cancer (rectal cancer located 10 cm or low from the anal verge in pelvis MRI)
  • Histologic type: adenocarcinoma, mucinous carcinoma, and signet ring cell carcinoma
  • Locally advanced rectal cancer with one or more of the following factors based on pelvis MRI: cTanyN1-2, cT3-4N0, or presence of extramural vascular invasion
  • MRI findings such as pelvic lymph node metastasis, anal sphincter invasion, and T4b are not included in the exclusion criteria, which cases will be enrolled by the researcher's discretion
  • Patients with appropriate organ (bone marrow, kidney, liver) function
  • A person who understands the study and willing to provide informed consent

Exclusion Criteria: (one of the following criteria)

  • Colon cancer or rectal cancer located more than 10 cm from the anal verge
  • Stage I rectal cancer (clinical stage cT1-2N0)
  • Clinically or pathologically diagnosed distant metastasis (cTanyNanyM1)
  • Familial adenomatous polyposis
  • Hereditary nonpolyposis colorectal cancer
  • History of chemotherapy or radiotherapy within 6 months
  • History of colorectal cancer or other type of malignancy within 5 years (except for cured nonmelanoma skin or in situ cervical cancer)
  • Comorbidities that make it difficult to undergo chemotherapy or radiotherapy
  • Bone marrow suppression with neutrophil count <2 ×109/L or platelet count <100 ×109/L prior to the first chemotherapy
  • Peripheral sensory neuropathy with functional impairment (grade 2 or higher)
  • Severe renal dysfunction (GFR ≤30ml/min by Wright or Cockroft formula)
  • Severe hepatic dysfunction
  • Genetic problems such as galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption
  • Taking tegafur, gimeracil, and oteracil potassium complex and those within 7 days of discontinuation
  • Taking sorivudine or brivudine
  • Significant heart disease or myocardial infarction within the last 6 months
  • Hereditary diseases or history of coagulopathy
  • Central nervous system disorders with disability or mental disorders
  • Pregnant or lactating women
  • Currently participating in other clinical trials or receiving research medication
  • Unhealed wounds, fractures, peptic ulcer, abscesses in the abdominal cavity
  • Active gastrointestinal bleeding
  • Active infections requiring antibiotics for injection
  • Emergency Surgery
  • History of hypersensitivity to the drugs in study protocol
  • Patients with non-malignant tumor diseases
  • Dihydropyrimidine dehydrogenase deficiency
  • Not willing to participate

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Study group
Short-course radiotherapy and 4 cycles of mFOLFOX6 followed by TME. Adjuvant chemotherapy will be given according to the pathological stage (CR~pStageI: 6 cycles of capecitabine or 4 cycles of 5-FU with leucovorin, pStageII-III: 8 cycles of mFOLFOX6)
Radiation: short-course radiotherapy
25 Gy in 5 fractions for 5 days
Drug: mFOLFOX6
Oxaliplatin 85 mg/m2, Levoleucovorin 200mg (or Leucovroin, Leucosodium 400mg)/m2, 5- FU 400 mg/m2, and continuous 5- FU 2,400 mg/m2 for 46 hours
Procedure: TME surgery
TME surgery
Active Comparator: Control group
Conventional chemoradiotherapy followed by TME. Adjuvant chemotherapy will be given according to the pathological stage (CR~pStageI: 6 cycles of capecitabine or 4 cycles of 5-FU with leucovorin, pStageII-III: 8 cycles of mFOLFOX6)
Procedure: TME surgery
TME surgery
Radiation: Chemoradiotherapy
45~50.4 Gy/25fr with concurrent use of either capecitabine or 5-FU+leucovorin(or levoleucovorin or leucosodium)

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
3-year disease-free survival
Time Frame: 3 years
To compare the 3-year disease-free survival between the experimental arm and the control arm
3 years

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
pCR rate
Time Frame: within 30 days after TME
CR (complete regression), no tumor cells and only fibrotic mass or acellular mucin pools
within 30 days after TME
Toxicity of neoadjuvant radiotherapy and chemotherapy
Time Frame: 6 months
Neoadjuvant treatment associated toxicity (Common Terminology Criteria for Adverse Events version v5.0)
6 months
R0 resection
Time Frame: within 30 days after TME
Rate of R0 resection of TME
within 30 days after TME
TRG
Time Frame: within 30 days after TME
Pathological tumor regression grade (TRG) (Dworak/Mandard/AJCC TRG classification)
within 30 days after TME
Surgical complications
Time Frame: within 60 days after TME
Surgical complications classified according to the Clavien-Dindo classification
within 60 days after TME
Incidence of peripheral neuropathy
Time Frame: 3 years
Incidence of oxaliplatin-induced peripheral neuopathy
3 years
European Organization for Research and Treatment of Cancer Quality of Life C30
Time Frame: 2 year after surgery
The EORTC Core Questionnaire (QLQ-C30) includes six clearly distinguishable functioning scales that have been thoroughly tested and validated on an international level and that are available in 110 different language versions
2 year after surgery
European Organization for Research and Treatment of Cancer Quality of Life CR29
Time Frame: 2 year after surgery
The QLQ-CR29 has five functional and 18 symptom scales. It contains four subscales (urinary frequency (UF), blood and mucus in stool (BMS), stool frequency (SF), and body image (BI)) and 19 single items (urinary incontinence, dysuria, abdominal pain, buttock pain, bloating, dry mouth, hair loss, taste, anxiety, weight, flatulence, fecal incontinence, sore skin, embarrassment, stoma care problems, sexual interest (men), impotence, sexual interest (women), and dyspareunia) [11]. Patients are asked to indicate their symptoms during the past week(s). Scores can be linearly transformed to provide a score from 0 to 100. Higher scores represent better functioning on the functional scales and a higher level of symptoms on the symptom scales.
2 year after surgery
Low Anterior Resection Syndrome score
Time Frame: 2 year after surgery
Low anterior resection syndrome (LARS) score ; 0 to 20 (no LARS), 21 to 29 (minor LARS ) and 30 to 42 (Major LARS )
2 year after surgery
The International Index of Erectile Function-5 score, retrograde ejaculation
Time Frame: 2 year after surgery
Quality of life IIEF-5, retrograde ejaculation
2 year after surgery
5-year disease-free survival
Time Frame: 5 years
To compare the 5-year disease-free survival between the experimental arm and the control arm
5 years
3-year overall survival
Time Frame: 3 years
To compare the 3-year overall survival between the experimental arm and the control arm
3 years
5-year overall survival
Time Frame: 5 years
To compare the 5-year overall survival between the experimental arm and the control arm
5 years
Loco-regional recurrence
Time Frame: 5 years
To compare the 3 year and 5-year loco-regional recurrence between the experimental arm and the control arm
5 years
Distant metastasis
Time Frame: 5 years
To compare the 3 year and 5-year distant metastasis between the experimental arm and the control arm
5 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Kyungpook National University Hospital

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Cancer Center, Korea

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
October 23, 2020

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 28, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 28, 2031

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
December 21, 2022

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
December 21, 2022

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 6, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
February 12, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
February 10, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
February 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • KNUHCRC007

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • CSR

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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