A comparison of physical examination and imaging in determining the extent of primary penile carcinoma

OBJECTIVE: To determine the accuracy of physical examination and imaging in assessing the extent of the primary tumour in squamous cell carcinoma of the penis. PATIENTS AND METHODS: A physical examination, ultrasonography and magnetic resonance imaging (MRI) were used before surgery in 33 patients with penile carcinoma. The tumour size, infiltration of the penile structures and infiltration depth were assessed. The results were compared with the histopathological examination of the resected specimen. RESULTS: Tumour size was determined with the highest precision by the physical examination (residual SD of 8.1 mm); ultrasonography and MRI were less precise (residual SD 8.9 mm and 9.3 mm). In assessing infiltration depth, ultrasonography and MRI had comparable precision (residual SD 3.7 mm and 3.8 mm). The positive predictive value of corpus cavernosum infiltration was 6/6 for physical examination, 4/6 for ultrasonography and 6/8 for MRI; the sensitivity was 6/7, 4/7 and 6/6, respectively. CONCLUSION: Physical examination is a reliable method for estimating penile tumour size and predicts corpus cavernosum infiltration with a high positive predictive value. Tumours for which the infiltration of the corpora cannot be determined properly by physical palpation only should be examined by imaging.