Detection of inguinal lymph node involvement in penile squamous cell carcinoma by 18F-fluorodeoxyglucose PET/CT: a prospective single-center study

Abstract

Background: The extent of lymph node involvement is the most relevant prognostic factor in patients with penile cancer.

Objective: To prospectively analyze the diagnostic accuracy of 18F-FDG-PET/CT-scan in the assessment of inguinal lymph node involvement in patients with invasive penile carcinoma.

Patients and methods: Thirty-five patients with invasive penile carcinoma were staged prospectively by 18F-FDG-PET/CT-scan, and blindly evaluated by 2 nuclear medicine physicians. In total, lymph node involvement was assessed in 70 inguinal groins. Reference standard was either histology or clinical follow-up with a minimum of 31 months (mean: 48.4 months; range: 31-68 months).

Results: 18-FDG-PET/CT showed a sensitivity of 88.2% and a specificity of 98.1%. Positive predictive value (PPV) was 93.8%, while negative predictive value (NPV) was 96.3%. In two groins, metastasis of 5 and 7 mm were missed by PET/CT scan.

Conclusion: 18F-FDG-PET/CT is a promising staging tool in assessing the inguinal lymph node involvement of patients with penile carcinoma. Integration of PET/CT scanning into preoperative staging algorithms may avoid surgical staging in selected patients.