Penile schwannoma:one case report and literature review / 中国基层医药

ABSTRACT

Objective To evaluate the clinical and pathological characteristics and treatment of penile schwannoma.Methods One case of penile schwannoma was reported,and the relevant literature was reviewed to investigate the histogenesis,diagnosis and treatment of this disease.Related literature from PubMed and Wanfang databases to date(up to April 2017)with"penis" or"penile" combined with "schwannoma" or"neurilemmoma" as search terms was reviewed.Results One 40-year-old male presented in October 2015 with a tumor at the root of the dorsal penis for 1 year.Physical examination revealed a non-tender,easily movable without adhesion to the skin,1.2cm ×0.8cm nodule at the root of the dorsal penis,the overlying skin was smooth and intact.No evidence of neurofibromatosis was found.Hypoechoic well-defined nodule(1.7cm ×0.4cm)located between the superficial skin and corpus cavernosum was showed on ultrasound without blood flow signal.Simple excision of the tumor was performed under local anesthesia.Grossly,the tumor was a well-defined,white,soft 1.5cm ×1cm ×0.7cm nodule.Microscopically,the tumor was composed of Antoni A area with hypercellular and nuclear palisading.Immunohistochemical staining showed S-100(+++),SMA(-),Act(-).The pathological diagnosis was penile schwannoma.Postoperatively,the patient recovered well without erectile dysfunction.During a follow-up 18 months,the patient had no recurrence.By literature review,we found 14 cases in Chinese articles with one malignant case,while 33 cases in English articles with six malignant cases.The average age of onset was 39.2 years.Most of the tumors are benign and located in the dorsal side of the penis.Penile schwannoma can be diagnosed properly based on pathological examination,owing to the lack of typical clinical and imaging manifestation.The tumor resection was the treatment of choice for benign penile schwannoma without postoperative complications.Conclusion Penile schwannoma is extreme rarity,but can be diagnosed properly based on postoperative pathological examination,owing to the lack of typical clinical and imaging manifestation.S-100 is a useful marker for the diagnosis of schwannoma.The tumor resection is the treatment of choice for benign penile schwannoma without erectile dysfunction or recurrence ;for the malignant,the final diagnosis relies on postoperative pathological examination after the secondary operation with local recurrence.The tumor resection combined with radiotherapy and chemotherapy is reliable treatment,but the prognosis is poor.