Gastric Adenocarcinoma, Stomach Neoplasms, Locally Advanced Gastric Cancer, Unresectable Gastric Cancer
Conditions
Keywords
HER2-negative Stomach Cancer, Microsatellite Stable Gastric Cancer
Brief summary
The purpose of this prospective, single-center, phase II study is to evaluate the clinical efficacy and safety of combining first-line systemic therapy plus immunotherapy with personalized ultrafractionated stereotactic adaptive radiation therapy (PULSAR) in patients with unresectable locally advanced gastric cancer.
Detailed description
Standard first-line treatment for unresectable locally advanced gastric cancer is systemic chemotherapy combined with immunotherapy, but the overall prognosis remains poor, and local complications like bleeding or obstruction frequently occur. ULSAR delivers a high dose of radiation per fraction using a 3-to-4 week interval. This extended fraction interval allows normal tissue recovery and provides an opportunity for adaptive replanning before each fraction to minimize gastrointestinal toxicities while maximizing tumor dose delivery. Furthermore, this unique scheduling allows seamless integration with systemic immunotherapy without interrupting the regular chemotherapy cycle. This study specifically aims to evaluate if PULSAR can improve local control, conversion to surgery, and progression-free survival in HER-2 negative, EBV negative, and MSS gastric cancer patients whose tumors have not progressed after at least 3 cycles of first-line immunotherapy-containing systemic regimens.
Interventions
RADIATIONPULSAR (Personalized Ultrafractionated Stereotactic Adaptive Radiation Therapy)
Dose Schedule: 6 Gy per fraction administered every 3-4 weeks
RADIATIONPULSAR
Administer a single dose of 6 Gy of radiation, up to a total of 3 cycles, at 3-4 week intervals, along with standard systemic therapy.
Sponsors
Samsung Medical Center
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Age 19 or more years. Eastern Cooperative Oncology Group (ECOG) Performance Status of 0-2. Histologically confirmed gastric adenocarcinoma. Tumor biomarker status: HER-2 negative, EBV negative, and Microsatellite Stable (MSS). Unresectable, locally advanced extent at initial staging (Para-aortic lymph node \[PALN\] and Supraclavicular lymph node \[SCN\] metastases are allowed). Has completed 3 or more cycles of first-line systemic therapy combined with immunotherapy without evidence of disease progression. Presence of at least one evaluable lesion according to RECIST v1.1 that is deemed safely irradiable by the investigator. Voluntary written informed consent provided by the subject.
Exclusion criteria
Pregnant or lactating women. Presence of brain metastases or leptomeningeal involvement. Prior history of radiation therapy to the intended target site. Severe uncontrolled comorbidities that, in the investigator's opinion, limit study participation or treatment compliance (e.g., uncontrolled infection, heart failure, arrhythmia, psychiatric illness). Inability or unwillingness to comply with the study protocol procedures. Any condition deemed inappropriate for study participation by the principal investigator or attending physician.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Progression-Free Survival (PFS) Rate at 12 Months | PFS at 12 months, calculated from the end date of the 1st PULSAR fraction. | Defined as the percentage of patients alive without any evidence of disease progression per RECIST v1.1 at 12 months, calculated from the end date of the 1st PULSAR fraction. |
Countries
South Korea
Contacts
CONTACTJeong Il Yu
Outcome results
None listed