Umbilical squamous papilloma: A case report

A 21-year-old Caucasian male presented with a 2-year history of an asymptomatic mass in the umbilicus. The patient stated that the lesion increased in size gradually. Therefore, the patient was complaining of cosmetic disfigurement. However, he did not receive any treatment previously. The past medical history and family history were both unremarkable. The patient denied any trauma to the umbilical region.


Sir,
A 21-year-old Caucasian male presented with a 2-year history of an asymptomatic mass in the umbilicus. The patient stated that the lesion increased in size gradually. Therefore, the patient was complaining of cosmetic disfigurement. However, he did not receive any treatment previously. The past medical history and family history were both unremarkable. The patient denied any trauma to the umbilical region.
The physical examination of the patient revealed a skin colored pedunculated plaque with verrucous surface in the umbilicus measuring 1.5x1 cm in size (Fig. 1). The lesion was removed surgically under local anesthesia to reach a definitive diagnosis. Histopathological evaluation of the specimen revealed multiple finger-like projections supported by central fibrovascular cores which were covered by a stratified squamous epithelium. The longest diameter of the polipoid lesion was 1.5 cm. However, the diameter of the basis of the lesion was measured 0.4x0.3 cm. No evidence of malignancy or koilocytic changes in the epithelium were observed. The diagnosis of squamous papilloma was made based on clinical and histopathological features (Fig. 2).
Squamous papilloma is a benign neoplastic proliferation with finger like morphology which usually affects skin, cervix, breast duct, respiratory tract and gastrointestinal tract. Human papilloma virus (HPV) infection plays role in the etiology of squamous papilloma [1].
It has been suggested that stem cell population of the hair follicle which contains keratin 15 might contribute to the development of squamous papilloma. Li et al.  Terada reported a 46-year-old female patient with a squamous papilloma measuring 13 mm in size on the scalp, arising from an epidermal cyst. Squamous papilloma showed intracystic growth with fibrovascular cores. The tumor had benign character, and thus no atypia was observed. Immunohistochemical evaluation showed no association between squamous papilloma and HPV. Terada reported that squamous papilloma could arise in epidermal cysts. Therefore, differential diagnosis of squamous papilloma from trichilemmal tumor and proliferating trichilemmal cyst should be made [3].
Squamous papilloma of the umbilicus is a rare condition. Vijayabhaskar et al. reported a 47-year-old female patient with microinvasive squamous cell carcinoma of the cervix and benign squamous papilloma in the umbilicus at the same time [4]. Nathan reported coexistence of squamous papilloma arising from the umbilicus and genital warts. Nathan suggested possible role of autoinoculation from genital region to umbilicus during bathing [5].
Verrucous carcinoma is a differentiated type of squamous cell carcinoma which presents as a slow growing warty papule. Differential diagnosis of squamous papilloma from verrucous carcinoma is crucial as the verrucous carcinoma can lead to local invasion and metastasis. The risk of misdiagnosis increases in laryngeal lesions and in cases when the biopsy specimen is small [6]. In addition, Kim et al. reported a 20-year-old female patient with condyloma lata in the umbilicus, perineum and mucous patches on the lips. Even it is rare, syphilis should be kept in mind in the differential diagnosis of verrucous nodules in the umbilicus [7].
In conclusion, the patient presented hereby had a lesion diagnosed as squamous papilloma in the umbilicus which was an unusual localization for squamous papilloma. Possible initiating factors such as HPV infection, chronic irritation and rare diseases such as verrucous carcinoma and syphilis in the differential diagnosis of squamous papilloma are reminded through this case report.

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The examination of the patient was conducted according to the Declaration of Helsinki principles.