바로가기  >

Abstract
Background and purpose: The ability of the effective dose to immune cells (EDIC) and the pre-radiotherapy (RT) absolute lymphocyte count (ALC) to predict lymphopenia during RT, treatment outcomes, and efficacy of consolidation immunotherapy in patients with locally advanced non-small cell lung cancer was investigated.

Methods and materials: Among 517 patients treated with concurrent chemoradiotherapy, EDIC was calculated using the mean doses to the lungs, heart, and total body. The patients were grouped according to high and low EDIC and pre-RT ALC, and the correlations with radiation-induced lymphopenia and survival outcomes were determined.

Results: Altogether, 195 patients (37.7%) received consolidation immunotherapy. The cutoff values of EDIC and pre-RT ALC for predicting severe lymphopenia were 2.89 Gy and 2.03 × 109 cells/L, respectively. The high-risk group was defined as EDIC ≥ 2.89 Gy and pre-RT ALC < 2.03 × 109 cells/L, while the low-risk group as EDIC < 2.89 Gy and pre-RT ALC ≥ 2.03 × 109 cells/L, and the rest of the patients as the intermediate-risk group. The incidences of severe lymphopenia during RT in the high-, intermediate-, and low-risk groups were 90.1%, 77.1%, and 52.3%, respectively (P < 0.001). The risk groups could independently predict both progression-free (P < 0.001) and overall survival (P < 0.001). The high-risk group showed a higher incidence of locoregional and distant recurrence (P < 0.001). Consolidation immunotherapy showed significant survival benefit in the low- and intermediate-risk groups but not in the high-risk group.

Conclusions: The combination of EDIC and pre-RT ALC predicted severe lymphopenia, recurrence, and survival. It may potentially serve as a biomarker for consolidation immunotherapy.

EDIC와 pre-RT ALC로 분류한 위험군에 따른 무진행 생존율과 전체 생존율. 무진행 생존율 (A), 전체 생존율 (B).

위험군에 따른 국소 재발 및 원격 전이+/-국소 재발의 누적 발생률. 국소 재발 (A), 원격 전이+/-국소 재발 (B).

Affiliations

Gowoon Yang 1, Hong In Yoon 1, Joongyo Lee 1, Jihun Kim 2, Hojin Kim 1, Jaeho Cho 1, Chang Geol Lee 1, Jee Suk Chang 1, Yeona Cho 2, Jin Sung Kim 1, Kyung Hwan Kim 3
1Department of Radiation Oncology, Yonsei Cancer Center, Heavy Ion Therapy Research Institute, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
2Department of Radiation Oncology, Gangnam Severance Hospital, Yonsei University College of Medicine, 211 Eon-ju-ro, Gangnam-gu, Seoul 06273, Republic of Korea.
3Department of Radiation Oncology, Yonsei Cancer Center, Heavy Ion Therapy Research Institute, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea. Electronic address: KYUNGHKIM@yuhs.ac.