This is concerning as undescended testes do have predisposition for the tumors and they need to be removed as soon as possible. After the biopsy and further investigations like ultrasound and CT scan of the abdomen, they would determine, whether he would need additional treatment like chemotherapy.
Please feel free for your follow up questions.
The biopsy will dictate the further management. Some tumor are radiosensitive (so radiotherapy is used) while some may require chemotherapy or combination of the both. The CT scan and an ultrasound would determine the staging and it may only be localized to the undescended testes only. The prognosis is then quite good.
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