Characterization of brain metastases from lung cancer using percentagewise quantification of intratumoral susceptibility signals

Linlin Sun; Jing Chen; Xuemei Liu; Huiyuan Zhu; Haiyang Dong; Guangyu Tao; Yifei Cao; Han Chu; Hong Yu; Qunhui Chen; Li Zhu; Shihai Luan

doi:10.21037/qims-24-1505

Characterization of brain metastases from lung cancer using percentagewise quantification of intratumoral susceptibility signals

Quant Imaging Med Surg. 2025 Jun 6;15(6):5373-5383. doi: 10.21037/qims-24-1505. Epub 2025 Jun 3.

Authors

Linlin Sun^#¹, Jing Chen^#¹, Xuemei Liu^#¹, Huiyuan Zhu¹, Haiyang Dong¹, Guangyu Tao¹, Yifei Cao², Han Chu³, Hong Yu¹, Qunhui Chen¹, Li Zhu¹, Shihai Luan^{4

5

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Affiliations

¹ Department of Radiology, Shanghai Chest Hospital, School of Medicine, Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
² School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China.
³ Shanghai Jianping High School, Shanghai, China.
⁴ Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China.
⁵ Institute of Neurosurgery, Fudan University, Shanghai, China.
⁶ Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Fudan University, Shanghai, China.

^# Contributed equally.

Abstract

Background: Percentagewise quantification (PQ) of intratumoral susceptibility signals (ITSS) on susceptibility weighted imaging (SWI) serves as an objective and quantitative method capable of differentiating some primary entities of brain metastases (BMs). We aimed to evaluate PQ of ITSS in BMs of different sizes in three main lung cancer subtypes, and explore if it can improve differential diagnosis in the context of lung cancer.

Methods: In this retrospective study, 213 patients with synchronous BMs from lung cancer [141 adenocarcinoma (AD), 28 squamous cell carcinoma (SCC), 44 small cell lung cancer (SCLC)], who underwent routine brain contrast-enhanced magnetic resonance imaging (MRI) and contrast-enhanced SWI (CE-SWI), were enrolled. The BMs were delineated on CE-SWI by mutual consent of two radiologists. All voxels within the lesion and voxels presenting values lower than those of the ventricular system were evaluated separately, and then ITSS were percentagewise calculated. The incidence of PQ <1% (no ITSS) and PQ of ITSS in Group 1 (micrometastases, ≤0.125 cm³), Group 2 (middle metastases, 0.125 cm³< size <27 cm³) and Group 3 (macrometastases, ≥27 cm³) from the three subtypes of lung cancer were compared.

Results: The incidence of no ITSS in Group 1 was higher than that in Groups 2 and 3 in the three subtypes of lung cancer. BMs in Group 2 and Group 3 had higher PQ of ITSS than those in Group 1. In Group 3, PQ of ITSS in AD was higher than that in SCC (P=0.016) and in SCLC (P=0.010), while there was no difference between SCC and SCLC (P=0.921). Diagnostic performance of PQ of ITSS in Group 3 was good [area under the receiver operating characteristic curve (AUC) =0.81; 95% confidence interval (CI): 0.64, 0.98] to discriminate AD from non-AD. At a cut off value of 6.68%, the sensitivity and specificity for differentiation of AD and non-AD were 0.92 and 0.71, respectively.

Conclusions: PQ of ITSS can contribute to the non-invasive characterization of BMs from the three subtypes of lung cancer. The larger lesions (middle metastases and macrometastases) of BMs were more likely to have positive ITSS and exhibited higher PQ of ITSS than small ones (micrometastases), and macrometastases of AD and non-AD can be distinguished with high sensitivity and specificity.

Keywords: Brain metastases (BMs); lung cancer; susceptibility weighted imaging (SWI).