Inguinal/pelvic lymph node involvement in penile squamous cell carcinoma by ¹⁸F-fluorodeoxyglucose PET/CT

To evaluate the diagnostic accuracy of ¹⁸F-fluorodeoxyglucose positron emission tomography combined with computed tomography (¹⁸F-FDG PET/CT) for detecting inguinal and pelvic lymph node metastases in penile squamous cell carcinoma (SCC).

A systematic review and meta-analysis of diagnostic accuracy studies was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Databases were systematically searched, and studies reporting sufficient data to construct 2 × 2 tables were included. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Pooled estimates were calculated using random-effects models.

A total of 16 studies were included in the qualitative synthesis and eight in the meta-analysis. The pooled sensitivity was 0.84 (95% confidence interval [CI] 0.74-0.90) and specificity was 0.85 (95% CI 0.75-0.91). The diagnostic odds ratio was 20.57 (95% CI 9.76-43.37). The positive likelihood ratio was 3.49, and the negative likelihood ratio was 0.25, indicating moderate ability to confirm disease but limited capacity to exclude it. The hierarchical summary receiver operating characteristic curve demonstrated overall good diagnostic performance.

Use of ¹⁸F-FDG PET/CT shows good diagnostic performance for nodal staging in penile SCC, particularly as a confirmatory tool. However, its limited ability to exclude disease, especially in clinically node-negative patients, supports its use within a multimodal diagnostic approach rather than as a standalone test.