Sintilimab, Chidamide, and Azacitidine for Untreated Stage I-II Extranodal NK/T-Cell Lymphoma

objective response rate

the objective response rate (orr) is defined as the proportion of participants who achieve either a complete remission (cr) or a partial remission (pr) as their best overall response during the systemic treatment phase. assessments will be conducted by the investigator in accordance with the lugano classification 2014 criteria for malignant lymphoma (or recil 2017 if applicable). this measure evaluates the combined efficacy of the induction and consolidation regimens (sca and/or p-gemox) in reducing tumor burden prior to the administration of local radiotherapy. * complete remission (cr): disappearance of all target lesions, normalization of lymph nodes, and metabolic complete response (deauville score 1-3). * partial remission (pr): ≥50% decrease in the sum of the products of the perpendicular diameters of target lesions, taking into account the appearance of new lesions or flares in fdg-avid disease.

Time frame: From Baseline to the End of Systemic Treatment or the completion of 6 cycles (each cycle is 21 days), whichever occurs first.

Partial Remission (PR) rate

The Partial Remission (PR) rate is defined as the proportion of participants who achieve a Partial Remission (PR) as their best overall response during the study treatment period. Tumor response will be assessed by the Investigator according to the Lugano Classification 2014 criteria (or RECIL 2017 if applicable). This endpoint measures the efficacy of the SCA induction regimen and subsequent response-adapted therapy (SCA consolidation or P-GemOx chemotherapy) in reducing the tumor burden in patients with previously untreated ENKTL. A PR is defined as a ≥50% decrease in the sum of the products of the perpendicular diameters of target lesions, taking into account the appearance of new lesions or flares in FDG-avid disease.

Time frame: From Baseline to the End of Systemic Treatment or the completion of 6 cycles (each cycle is 21 days), whichever occurs first.

Progression-Free Survival

The Progression-Free Survival (PFS) is defined as the time from the date of initial treatment (first dose of the SCA regimen) to the date of disease progression or death from any cause, whichever occurs first. Disease progression will be determined by the Investigator based on radiological imaging (CT/MRI) and clinical assessment according to the Lugano Classification 2014 criteria (or RECIL 2017). Patients who do not experience the event (progression or death) at the time of data cutoff will be censored at the date of their last adequate disease assessment. Patients who initiate new anti-cancer therapy without documented progression will also be censored at the start date of the new therapy.

Time frame: From date of initial treatment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 24 months.

Duration of Response

The Duration of Response (DoR) is defined as the time from the date of first documented response (either Complete Remission or Partial Remission) to the date of disease progression or death from any cause, whichever occurs first. Disease progression will be determined by the Investigator based on radiological imaging and clinical assessment according to the Lugano Classification 2014 criteria (or RECIL 2017). Only participants who achieve a CR or PR are evaluable for this endpoint. Patients who do not experience the event (progression or death) at the time of data cutoff will be censored at the date of their last adequate disease assessment.

Time frame: From date of first documented response until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 24 months.

Overall Survival

The Overall Survival (OS) is defined as the time from the date of initial treatment (first dose of the SCA regimen) to the date of death from any cause. Patients who are alive at the time of the data cutoff or who are lost to follow-up will be censored at the date of their last known contact. This endpoint serves as a key measure of the long-term efficacy and clinical benefit of the sequential SCA and P-GemOx regimen combined with radiotherapy in the treatment of previously untreated ENKTL.

Time frame: From date of initial treatment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 36 months.

Adverse Events

The incidence and severity of Adverse Events (AEs) will be monitored and recorded throughout the study. This includes all untoward medical occurrences, laboratory abnormalities (hematology and chemistry), and serious adverse events (SAEs). The severity of each AE will be graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 5.0. The assessment will focus on the safety and tolerability of the SCA induction regimen (Sintilimab, Chidamide, and Azacitidine), the response-adapted consolidation therapy (SCA or P-GemOx), and the subsequent involved-field radiotherapy.

Time frame: From the date of informed consent and first dose of study drug up to 30 days (or 90 days for immune-related AEs) after the last dose of study treatment or completion of radiotherapy.