Multiple Epidermoid Cysts of Penis

Penile epidermoid cysts are very rare. Multiple penile epidermoid cysts found in a 23 year old case were presented. The cysts were present for 5 years. There was no history of previous surgery, trauma and infection. The case referred due to cosmetic concerns. Each one of cysts was totally excised together with capsule. In the pathologic examination, the result was reported as penile epidermoid cyst. In the follow-up, malignant transformation and recurrence did not occur.


INTRODUCTION
Epidermoid cysts are most common cyst form of the skin.It can occur on skin throughout all parts of the body, particularly in face, neck, head and thoraco-abdominal region.Penile epidermoid cysts are very rare.Although there are several individual cases reported in the literature, no case with multiple penile epidermoid cysts was found (1,2).Etiological reason of those lesions has not been clearly identified.It may be congenital or acquired.In the etiology of acquired cysts, trauma or previous surgery can be considered.Considering the underlying cause of congenital cysts, epidermoid cysts are regarded as different entities, although cysts originating from median raphe are indicated (1,3).

CASE
A 23-year old male subject referred due to several painless swollen lesions in the penis, which had gradually increased in number throughout five years.In the medical history, it was found that there was no previous infection, trauma or surgical intervention in the region, the subject did not seek medical help due to those lesions and no intervention was made on lesions.In the physical examination, it was observed that lesions were localized on penile shaft, dorsal and dorsolateral region, and there were five cystic swollen lesions, with largest one sized 1 cm, which were characterized with smooth surface, soft consistence, painless and the lesions were freely moving (Figure 1).It was observed that the case had no similar lesions in other parts of the body.Lesions were individually excised under local anesthesia.It was found in sections of the lesions that the lesions contained macroscopic cheese-like material and in the histopathological examination, it was comprised of stratified squamous epithelium (Figure 2).No post-operative complication occurred and the case was discharged in the same day.Recurrence did not occur in the two-year follow-up.

DISCUSSION
Epidermoid cysts of penis are mostly solitary, but multiple ones are very rare.Development of cysts on mid-line leads to the speculation that they are mostly congenital and they originate from median raphe.Cysts reported in the literature are largely those mid-line cysts (3,4).
Those cysts may develop at any place ranging from urethral meatus to anus along the genitoperineal raphe.It is believed that the condition is sequel of a prevalent failure during embryological development of male genital system (2,5).The part of those cysts deriving from urethra has ecto-dermal origin, but the parts deriving from urethral residues have endo-dermal origins.Three histopathological types were defined including urethral, epidermoid and mixed.The most common one is the urethral type (70 %) (1,4).In our case, the histopathological examination revealed out that the cysts were comprised of stratified squamous epithelium.Epidermal cysts most frequently develop in scrotum in the extragenital system and they are multi-focal.It is also known as scrotal sebaceous cyst.Acquired multi-focal epidermoid cyst on penis skin is not found in the literature.The case presentation by Singh et al. reported unilateral penile ventrolateral cyst (1).In another study, penoscrotal epidermoid cyst developed following hypospadias surgery was reported (5).Similar to our case, no penile involvement with multiple cysts was found in the literature.Dermoid cysts, teratomas, pylonoidal cysts and urethral diverticula should be considered in the differential diagnosis.However, as it can be seen in the figure, the appearance of painless mobile mass lesion containing white caseous material is enough for making the diagnosis (Figure 1).The treatment indications of such cysts include pain during intercourse, secondary infections and cosmetic deformity.The referral cause of our case was the discomfort arising from cosmetic deformity.Due to the age of the case, lesions were totally excised, together with the capsule beneath the lesion, under local anesthesia.There is risk of aspiration and simple drainage recurrence.It was reported that in scrotal cysts, re-excision is required in cases where residual tissue is left after the treatment (6).Neoplastic transformation was reported, although rare, in other parts of the body.However, malignant transformation was not reported in penile epidermoid cysts (1,2,7).

Figure 1 .
Figure 1.Multiple epidermoid cysts on dorsal and dorsolateral surface of penis