ºÚÁÏÍø

70-year-old man was referred to hospital with the complaints of left testicular pain. In clinical examination, left testis was found as a palpable hard nodule. Right testis was completely normal. Patient had no past history and trauma. Evaluated laboratory tests showed no abnormal findings. Serum alpha-fetoprotein, beta-HCG and LDH were between normal range limits. Ultrasonography showed left testis larger than the right testis. Lesion was present in testicular parenchyma without invasion into the capsule.

According to clinical and radiographic finding evaluation we diagnosed an initial testicular tumour primarily. The patient underwent orchiectomy of the testicular mass. Then, we performed a frozen section to rule out surgical margins malignancy. The resected mass was measured 5.2 × 7.5 × 1.0 cm. Cut section revealed a welldefined keratinizing cystic mass. Histologic findings revealed a benign cystic lesion lined by stratified squamous epithelium with a prominent granular cell layer. The cyst lumen is filled with the abundant keratin (Figure1). There was no evidence of malignancy. A final diagnosis of epidermoied cyst confirmed. The patient is under regular follow-up since last 10 months without any evidence of recurrence 10 months without any evidence of recurrence.

Figure 1: Histologically, the cystic lesion lined by stratified squamous epithelium with a prominent granular cell layer. The cyst lumen is filled with the abundant keratin. (H&E magnification X20).

Epidermal cysts are more common in men as in women [4-6]. Testicular epidermoid cyst is very rare .These benign lesions are about 3% of all testicular tumours [7]. The histopathologic features of testicular epidermoid cysts are similar with skin's epidermoid cysts [8]. Microscopically, epidermoid cysts revealed, a cystic lesion covered by stratified squamous epithelium with a prominent granular cell layer. The cyst lumen is filled with the abundant keratin, debris and desquamated cells [9]. Although the epithelial lining not to have malignant potential but malignant changes of basal cell carcinoma or squamous cell carcinoma from epidermal cysts have been reported [10]. Testicular sonographic findings in epidermal cysts described a sharply defined mass with a hyperechoic rim “onion ring” appearance of alternating hypoechogenicity layers of compacted keratin [8]. Magnetic resonance imaging (MRI) findings in these cysts revealed well-defined solid masses surrounded by a fibrous capsule [5]. This finding is similar to our case. Epidermoid cysts the prognosis is good. This cysts usually treated by conservative surgical excision and recurrence is uncommon [4].

Although testicular epidermal cysts are benign epithelial cysts and occurring of these lesions is very rare, malignant transformation has been reported in some cases. Therefore patient’s follow-up is required.