Background: Rhabdomyosarcoma of the testis, epididymis, spermatic cord and rhabdomyosarcomas that are classified as para-testicular rhabdomyosarcomas tend to be rare and sporadically reported; hence many clinicians may not be familiar with the biological behaviour and management of the disease.
Aim: To review the literature on rhabdomyosarcoma of the testis, epididymis, spermatic cord including all tumours that are referred to as para-testicular rhabdomyosarcoma. Method: Various internet data bases were searched.
Results/Review: Rhabdomyosarcomas tend to represent primitive malignant round cell tumours that have skeletal muscle differentiation determined by immunohistochemistry and ultrastructural studies. Rhabdomyosarcomas of the testis, epididymis, spermatic cord and the para-testicular region are rare and they tend to represent about 7% of all rhabdomyosarcomas and about 6% of all para-testicular tumours. One out of about 20 million males in one year tends to develop these types of tumours. No preference for race or side has been established. These tumours tend to spread via the lymphatic system to iliac lymph nodes; nevertheless, spread via the blood stream to the liver and lungs do occur. These tumours most commonly tend to present as painless lump or mass within the testis/para-testicular region and the history tends to be short of few days to weeks duration. Occasionally patients may present with pain, fever, vomiting, and abdominal distension as well. On examination there tends to be a palpable lump related to the testis or epididymis, spermatic cord or para-testicular region and the lump could be inguinoscrotal. One third to half of these tumours may be associated with metastases. Diagnosis of a tumour within the testis, epididymis, spermatic cord or para-testicular region tends to be suspected on clinical examination, radiology imaging and this tends to be confirmed by means of histopathology examination an immunohistochemistry studies. Routine haematology and biochemistry test results tend to be normal and serum ß-HCG, AFP, and LDH tend to be normal. In some cases associated with liver metastases the liver function test results could be abnormal. Children and adults could develop the tumour. Ultrasound scan would tend to show a mass in the testis or para-testicular region with increased vascularity or mass compressing the testis. MRI scan could show a heterogeneously enhancing mass within the testis or a mass in the para-testicular region compressing the testis. CT TAP or MRI TAP could be utilized to stage the tumour. Treatment options tend to include surgical excision and chemotherapy; radiotherapy for local disease control could be offered; retroperitoneal lymph node dissection tends to be undertaken when there is radiology imaging evidence of lymph node enlargement. Gross examination of the specimen tends to show encapsulated, lobulated, smooth, grey-whitish tumour and these may have foci of haemorrhage, necrosis or cystic degeneration. Microscopic examination may show rhabdomyoblasts and undifferentiated primitive cells, tadpole cells, spindle cells and variable mitotic activity. Immunohistochemistry studies may show positive staining for Desmin, myoglobin, myosin, MSA, MyoD1, Myogenin, and rarely they may express cytokeratin. The outcome following treatment for localized disease tends to be better than when there are metastases. Poor prognosis tends to be related to age especially when he patients are aged less than one year or equal to or more than 10 years. Prognosis also tends to be affected by the classification of the tumour based upon the Intergroup Rhabdomyosarcoma Study Group’s International Classification of Rhabdomyosarcoma.
Conclusion: Rhabdomyosarcoma of the testis, epididymis, spermatic cord including all tumours classified as para-testicular rhabdomyosarcoma are rare tumours with aggressive potential that tend to present with a short history; these tumours tend to be associated with normal tumour makers; diagnosis tends to be confirmed by the histopathology features and typical immunohistochemistry features (some of which include (positive staining for myogenin, desmin, actin, vimentin, and others as stated in the paper); treatment tends to be by means of surgical excision and chemotherapy; prognosis tends to be worse for advanced metastatic disease and in patients who are less than 1 year-old or equal to or greater than 10 years old as well as upon the classification of the tumour.
