Magnetic resonance imaging of penile paraffinoma: case report

BACKGROUND: Penile paraffinoma is a well-known delayed complication of paraffin oil injection into the penis for penile girth augmentation but its MRI features have not been previously described. CASE PRESENTATION: A 35-year-old Ukraine man presented with erectile dysfunction, voiding difficulty and an irregular, hard and painful penile mass that had progressively grown over the last year. He reported having received, seven years before, several penile injections of paraffin oil for penile girth augmentation. On physical examination, the mass was tender, poorly delimited, and involved the whole penile shaft and the cranial part of the scrotum. Preoperative MRI, performed to determine the extent of tissue to be removed and the possibilities of penile reconstruction, showed a newly-formed homogeneous tissue, compressing but not infiltrating Buck’s fascia, iso-hypointense relative to muscle on T1-weighted sequences, and with a low signal intensity at T2-weighted sequences. On T1-weighted fat suppressed sequences, it did not enhance with contrast administration. MRI data were confirmed by surgical findings, as the newly-formed scar tissue did not infiltrate Buck’s fascia. Pathology confirmed the diagnosis of penile paraffinoma. CONCLUSION: MRI seems to provide an adequate imaging of the histological events occurring after injection of paraffin oil in the subcutaneous tissues. Penile paraffinoma remains a clinical diagnosis, but MRI features may be helpful in planning an adequate surgical strategy and, in selected cases, establishing the differential diagnosis with other penile diseases, including cancer.