Magnetic resonance imaging-derived radiomic signature predicts locoregional failure after organ preservation therapy in patients with hypopharyngeal squamous cell carcinoma

Abstract

Background and purpose: To develop and validate a magnetic resonance imaging (MRI)-derived radiomic signature (RS) for the prediction of 1-year locoregional failure (LRF) in patients with hypopharyngeal squamous cell carcinoma (HPSCC) who received organ preservation therapy (OPT).

Material and methods: A total of 800 MRI-based features of pretreatment tumors were obtained from 116 patients with HPSCC who received OPT from two independent cohorts. The least absolute shrinkage and selection operator regression model were used to select the features used to develop the RS. Harrell's C-index and corrected C-index were used to evaluate the discriminative ability of RS. The Youden index was used to select the optimal cut-point for risk category.

Results: The RS yielded 1000 times bootstrapping corrected C-index of 0.8036 and 0.78235 in the experimental (n = 82) and validation cohorts (n = 34), respectively. With respect to the subgroup of patients with stage III/IV and cT4 disease, the RS also showed good predictive performance with corrected C-indices of 0.760 and 0.754, respectively. The dichotomized risk category using an RS of 0.0326 as the cut-off value yielded a 1-year LRF predictive accuracy of 79.27%, 79.41%, 76.74%, and 71.15% in the experimental, validation, stage III/IV, and cT4a cohorts, respectively. The low-risk group was associated with a significantly better progression-free laryngectomy-free and overall survival outcome in two independent institutions, stage III/IV, and cT4a cohorts.

Conclusion: The RS-based model provides a novel and convenient approach for the prediction of the 1-year LRF and survival outcome in patients with HPSCC who received OPT.

Keywords: Hypopharyngeal squamous cell carcinoma; Loco-regional failure; Organ preservation treatment; Radiomics; Survival.

Fig. 1

(A) Scheme of the recruitment pathway of patients with HPSCC into the experimental cohort and validation cohort (B) Flowchart: radiomic signature development process including image pre-processing, image feature extraction, and selection of radiomic factors to generate the radiomic signature. HPSCC, hypopharyngeal squamous cell carcinoma; GLCM, gray-level co-occurrence matrix; GLRL, gray-level run-length; LASSO, the least absolute shrinkage and selection operator.

Fig. 2

Distribution of the individual RS for the 1-year loco-regional failure in two cohorts. (A) A waterfall plot illustration for the distribution of the individual RS_score for the 1-year loco-regional recurrence subgroup and 1-year locoregional disease-free subgroup; upper panel, experimental cohort; lower panel, validation cohort (B) Receiver operating characteristic curve used to evaluate the prediction performance of RS in the experimental cohort (upper panel) and in the validation cohort (lower panel). RS, radiomic signature.

Fig. 3

Kaplan–Meier survival curve for patients in the Institution 1 cohort (A) Progression-free survival (B) Laryngectomy-free survival (C) Overall survival; and the Kaplan–Meier survival curve for patients in the Institution 2 cohort (D) Progression-free survival (E) Laryngectomy-free survival (F) Overall survival.

Supplementary figure 1