RECIST 1.1、irRC、iRECIST基準に基づく半自動ソフトウェアによる免疫療法の奏効評価：主観的評価との比較

Response evaluation for immunotherapy through semi-automatic software based on RECIST 1.1, irRC, and iRECIST criteria: comparison with subjective assessment.

• Ying-Chieh Lai
• Wen-Cheng Chang
• Chun-Bing Chen
• Chi-Liang Wang
• Yu-Fen Lin
• Ming-Mo Ho
• Chi-Yuan Cheng
• Pei-Wei Huang
• Chao-Wei Hsu
• Gigin Lin

抄録

背景:

免疫療法を受けている患者では仮性増悪の診断は困難である。主観的な反応評価は、臨床の現場ではまだ一般的である。

BACKGROUND: Pseudoprogression is difficult to diagnose in patients undergoing immunotherapy. Subjective response assessment is still common in clinical practice.

目的:

固形腫瘍バージョン1.1（RECIST 1.1）、免疫関連奏効基準（irRC）、免疫療法のための修正RECIST 1.1（iRECIST）の奏効評価基準の違いを半自動ソフトウェアを用いて評価し、iRECISTに基づく奏効評価と主観的評価を比較すること。

PURPOSE: To evaluate the differences between response evaluation criteria in solid tumors version 1.1 (RECIST 1.1), immune-related response criteria (irRC), and modified RECIST 1.1 for immunotherapy (iRECIST) through semi-automatic software, and to compare iRECIST-based response evaluation with subjective assessment.

材料と方法:

RECIST 1.1, irRC, iRECISTに基づく各患者の最良の全奏効率を半自動ソフトウェアを用いてCTスキャン上で決定し、基準間の差異を評価した。半自動ソフトウェアを用いた基準に基づく奏効率評価と、放射線診断報告書上の主観的評価を比較し、最良の奏効率と全生存率を相関させて評価した。

MATERIAL AND METHODS: The best overall response of each patient based on RECIST 1.1, irRC, and iRECIST was determined on CT scans through semi-automatic software and the differences between the criteria were evaluated. Criteria-based response evaluation through semi-automatic software was compared with subjective assessment on radiology report by correlating the best overall response to overall survival.

結果:

総症例数は21例（メラノーマ5例、非小細胞肺癌12例、肝細胞癌4例）であった。RECIST 1.1では進行性であったが、irRCとiRECISTでは非進行性であった2人の患者は、最終的に腫瘍反応を経験し、良好な転帰を示し、偽進行を示した。非進行性疾患と進行性疾患の患者の生存期間の差は、主観的評価（=0.501）よりもiRECISTに基づく奏効評価（=0.078）の方が良好に層別化されていた。

RESULTS: A total of 21 patients were included (five patients with melanoma, 12 patients with non-small-cell lung cancer, and four patients with hepatocellular carcinoma). Two patients with progressive disease by RECIST 1.1 but non-progressive disease by irRC and iRECIST eventually experienced tumor response and had favorable outcomes, indicating pseudoprogression. The survival difference between patients with non-progressive disease and progressive disease was better stratified through iRECIST-based response evaluation ( = 0.078) than that through subjective assessment ( = 0.501).

結論:

免疫療法における偽増悪は、irRCまたはiRECIST基準を利用した半自動ソフトウェアにより捕捉される可能性がある。

CONCLUSION: Pseudoprogression in immunotherapy may be captured through semi-automatic software utilizing irRC or iRECIST criteria. iRECIST-based response evaluation may provide a better survival stratification compared with subjective assessment.