Open AccessLymphopenia During Definitive Chemoradiotherapy in Esophageal Squamous Cell Carcinoma: Association with Dosimetric Parameters and Patient Outcomes
Author(s) -
Xu Hui,
Lin Maosheng,
Hu Yingying,
Zhang Li,
Li Qiaoqiao,
Zhu Jinhan,
Wang Shi,
Xi Mian
Publication year - 2021
Publication title -
the oncologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.176
H-Index - 164
eISSN - 1549-490X
pISSN - 1083-7159
DOI - 10.1002/onco.13533
Subject(s) - medicine , nomogram , chemoradiotherapy , oncology , stage (stratigraphy) , multivariate analysis , logistic regression , esophageal squamous cell carcinoma , t stage , radiation therapy , gastroenterology , carcinoma , cancer , paleontology , biology
Background The objective of this study was to investigate the relationship between clinical characteristics, as well as dosimetric parameters, and the risk of treatment‐related lymphopenia in esophageal squamous cell carcinoma (ESCC) treated with definitive chemoradiotherapy (CRT). Materials and Methods Clinical characteristics and dosimetric parameters were collected from 436 patients with ESCC who received definitive CRT from 2010 through 2017. Absolute lymphocyte counts (ALCs) were obtained before, during, and 1 month after CRT. Grade 4 (G4) lymphopenia was defined as ALC <0.2 × 10 9 /L during CRT. Logistic regression analysis was used to evaluate the effect of each factor on predicting G4 lymphopenia. The relationship between lymphopenia and overall survival (OS) was examined, and a nomogram was developed to predict OS. Results G4 lymphopenia was observed in 103 patients (23.6%) during CRT. Multivariate analysis indicated that planning target volume (PTV), lung V 10 , heart V 10 , performance status, and pretreatment lymphopenia were significant risk factors for G4 lymphopenia. Patients with G4 lymphopenia had significantly worse survival than those without. Based on multivariate analysis, clinical TNM stage, radiotherapy modality, pretreatment ALC, and G4 lymphopenia were predictive of OS and were incorporated into the nomogram, yielding a concordance index of 0.71. Conclusions G4 lymphopenia during definitive CRT was associated with larger PTVs, higher lung V 10 and heart V 10 , and worse survival. Implications for Practice The purpose of this study was to investigate the relationship between clinical characteristics, as well as dosimetric parameters, and the risk of treatment‐related lymphopenia in 436 patients with esophageal squamous cell carcinoma who received definitive chemoradiotherapy. Grade 4 (G4) lymphopenia was observed in 23.6% of patients during radiotherapy. G4 lymphopenia was associated with larger planning target volumes, higher lung V 10 and heart V 10 , and worse survival. Then, a nomogram was built based on multivariate analysis, yielding excellent performance to predict overall survival. Prospective studies are needed to investigate potential approaches for mitigating severe lymphopenia, which may ultimately convert into survival benefits.