T-cell receptor beta constant 1 flow cytometry for diagnosing clonality in mature T-cell neoplasms: a systematic review and meta-analysis of diagnostic accuracy

Clinical Snapshot

Key Findings

• P Value: Small-study effects p<0.001

• Effect Size: Pooled sensitivity 97.6% (95% CI: 95.1-99.4%), specificity 90.7% (95% CI: 76.0-99.3%)

• Primary Outcome: Diagnostic accuracy of TRBC1 flow cytometry for T-cell clonality detection

• Nnt Or Sensitivity: LR+ 10.9 (95% CI: 4.1-28.9), LR- 0.053 (95% CI: 0.025-0.12), DOR 339 (95% CI: 64-1,788)

• Confidence Interval: Sensitivity: 95.1-99.4%, Specificity: 76.0-99.3%

Clinical Application

Rapid, cost-efficient flow cytometry technique suitable for routine laboratory implementation Relevant to Australian haematology laboratories and pathology services. May require PBS consideration for reimbursement and standardisation through NPAAC guidelines for flow cytometry Patients with suspected mature T-cell lymphomas requiring clonality assessment in haematology and pathology services

Abstract

INTRODUCTION: Accurate assessment of T-cell clonality is key for diagnosing mature T-cell neoplasms. TRBC1-based flow cytometry provides a rapid, robust, and cost-efficient approach. This systematic review and meta-analysis assessed the diagnostic accuracy of TRBC1 flow cytometry (TRBC1-FC) for detecting T-cell clonality in mature T-cell neoplasms. CONTENT: We systematically searched Scopus, PubMed (MEDLINE), and Google Scholar for articles on TRBC1-FC diagnostic accuracy published up to July 1, 2025. Pooled sensitivity and specificity were estimated, between-study heterogeneity was evaluated and small-study effects were examined. SUMMARY: This meta-analysis included 10 studies. The pooled sensitivity was 97.6 % (95 % CI, 95.1-99.4 %) and specificity 90.7 % (95 % CI, 76.0-99.3 %). The pooled LR+ was 10.9 (95 % CI, 4.1-28.9), LR-was 0.053 (95 % CI, 0.025-0.12), and DOR 339 (95 % CI, 64-1,788). The HSROC curve demonstrated an AUC of 0.974 (partial AUC=0.970), confirming excellent global discriminatory capacity. Between-study heterogeneity was substantial (I2=83.3 %), mainly affecting specificity and DOR, while sensitivity remained highly consistent. No evidence of a threshold effect was found. Deeks' test showed significant small-study effects (p<0.001), and sensitivity analyses identified one influential study whose exclusion markedly reduced heterogeneity. These results confirm the high diagnostic performance and robustness of TRBC1-FC for T-cell clonality assessment. OUTLOOK: TRBC1-FC demonstrates high sensitivity and low LR-, supporting its role as a rule-out test. Variability in specificity, LR+ and DOR, mainly due to small-study effects, advises caution for rule-in use. Standardized protocols and cost-effectiveness analyses are needed before broad clinical adoption.

References

1. 1.Biaggioni, P. A., & Gonzalez, C. (2026). T-cell receptor beta constant 1 flow cytometry for diagnosing clonality in mature T-cell neoplasms: a systematic review and meta-analysis of diagnostic accuracy. Clinical Chemistry and Laboratory Medicine. https://doi.org/10.1016/j.modpat.2025.100725