Other Primary Penile Tumors

Anterior urethral tumors are rare, and usually of the squamous type rather than TCC,40,41 with survival highly dependent on local staged2 Penile tumors tend to present early and have a good prognosis; those of the bulbomembranous urethra

Fig. 4.12 T2-weighted sagittal image showing a recurrent transitional cell tumor of the urethra (white arrowheads). Subtle low signal in the corpus cavernosum (white arrows) indicates early invasion (confirmed on histology). Compare with Fig. 4.3 to see how easily this might be missed on a scan without alprostadil. The fluid in the proximal urethra (black arrows) is a sign of urethral obstruction are commoner but usually present later,40,43 although penis-preserving surgery is still feasible in some.44 Appearances on MRI and ultrasound are similar to other squamous tumors of the penis, although urethral obstruction (and visible fluid in the urethra proximal to the tumor) is expected earlier (Fig. 4.12).

Next, although over 95% of penile tumors are squamous, many other types occur.7 Hemangioma, lymphangioma, neurofibroma, and leiomyoma are benign tumors which have been described in the penis4 5 and are likely to have similar appearances to elsewhere. Epithelioid sarcomas are very rare, but important because they can mimic Peyronie's disease or chronic inflammation and have a propensity for local spread and recurrence and lymphatic involvement; T2 appearances are variable: sometimes the lesion is low signal (like fibrosis),46 others isointense to corpora on T2 images.47 Kaposi's sarcoma is very rare; there are no specific features to make the diagnosis but there are usually lesions elsewhere and MR is useful for delineating spread. Melanoma often presents late in the penis, with lymphatic spread48,49 and recurrence is common; a specific MR feature of melanoma metastases is hyperintensity on unenhanced T1-weighted sequences, and loss of signal on T2* images due to high protein content.50 Penile lymphoma most often occurs in the shaft (often outside the corpora), but is also seen in the glans, and may occur as a result of hematogenous spread or local extension. The signal intensity, as elsewhere in the body, is usually homogenous and intermediate on T1 and T2-weighted sequences, with reports of enhancement after iv contrast varying from 'minimal'26 to 'obvious'.27

Fig. 4.13 (a) Involvement of the penis with metastasis from renal cell carcinoma. Malignant priapism is one area where both Doppler ultrasound and contrast-enhanced scans may be useful. The presentation was with high-flow priapism (systolic velocity >50 cm/s). The velocity 1 week later fell to <20 cm/s and at this point an MR was performed. The T2-weighted image (b) shows subtle patchy signal in the corpora cavernosa but the subtracted postcontrast image shows peripheral enhancement most prominent at the corporal tips (white arrows), an atypical appearance for low flow-priapism, where persisting enhancement is usually seen at the base, and around the cavernosal vessels. Histology confirmed renal cell carcinoma

How To Reduce Acne Scarring

How To Reduce Acne Scarring

Acne is a name that is famous in its own right, but for all of the wrong reasons. Most teenagers know, and dread, the very word, as it so prevalently wrecks havoc on their faces throughout their adolescent years.

Get My Free Ebook

Post a comment