Apparent diffusion coefficient for differentiation between extra-nodal lymphoma and squamous cell carcinoma in the head and neck: a systematic review and meta-analysis

Akira Baba; Ryo Kurokawa; Mariko Kurokawa; Roberto Rivera-de Choudens; Ashok Srinivasan

doi:10.1177/02841851241228487

Apparent diffusion coefficient for differentiation between extra-nodal lymphoma and squamous cell carcinoma in the head and neck: a systematic review and meta-analysis

Acta Radiol. 2024 Feb 20:2841851241228487. doi: 10.1177/02841851241228487. Online ahead of print.

Authors

Akira Baba^{1

2}, Ryo Kurokawa^{1

3}, Mariko Kurokawa^{1

3}, Roberto Rivera-de Choudens¹, Ashok Srinivasan¹

Affiliations

¹ Division of Neuroradiology, Department of Radiology, University of Michigan, Ann Arbor, MI, USA.
² Department of Radiology, The Jikei University School of Medicine, Minato-ku, Tokyo, Japan.
³ Department of Radiology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.

PMID: 38377681
DOI: 10.1177/02841851241228487

Abstract

Background: Radiological differentiation between extra-nodal lymphoma and squamous cell carcinoma in the head and neck is often difficult due to their similarities.

Purpose: To evaluate the diagnostic benefit of apparent diffusion coefficient (ADC) calculated from diffusion-weighted imaging (DWI) in differentiating the two.

Material and methods: A systematic review was performed by searching the MEDLINE, Scopus, and Embase databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement. Forest plots and the pooled mean difference of ADC values were calculated to describe the relationship between extra-nodal lymphoma and squamous cell carcinoma in the head and neck. Heterogeneity among studies was evaluated using the Cochrane Q test and I² statistic.

Results: The review identified eight studies with 440 patients (441 lesions) eligible for meta-analysis. Among all studies, the mean ADC values of squamous cell carcinoma was 0.88 × 10^-3mm²/s and that of lymphoma was 0.64 × 10^-3mm²/s. In the meta-analysis, the ADC value of lymphoma was significantly lower than that of squamous cell carcinoma (pooled mean difference = 0.235, 95% confidence interval [CI] = 0.168-0.302, P <0.0001). The Cochrane Q test (chi-square = 55.7, P <0.0001) and I² statistic (I² = 87.4%, 95% CI = 77.4-93.0%) revealed significant heterogeneity.

Conclusion: This study highlights the value of quantitative assessment of ADC for objective and reliable differentiation between extra-nodal lymphoma and squamous cell carcinoma in the head and neck. Conclusions should be interpreted with caution due to heterogeneity in the study data.

Keywords: Head and neck; apparent diffusion coefficient; lymphoma; meta-analysis; squamous cell carcinoma; systematic review.