My Son Has A Painful "lesion" In His Testicle. He

My son has a painful "lesion" in his testicle. He was put on antibiotics and but the lesion is still there. The urologist has ordered blood work and he has had an MRI. What kind of non cancerous lesions are there and if they find out it is cancer what is the prognosis The pain was slight then came on very strong in the summer. He is getting blood work this week. What would it be for? The urologist has also mentioned a biopsy. What will the blood work tell him?