Is it really impossible to do a testicular biopsy without removing the whole testicle for cancer screening?

Bx testicle: Yes, of course it is possible to take a sample without removing the whole testicle for a biopsy. The use of ultrasound and other diagnostics will precede the biopsy of course.

Possible, but ...: It's possible, but still proceed with surgery via inguinal incision for exploration so to decide if testis removal or biopsy with partial testis removal if surgeon is confident and pathologist's support is available. Most of times, radical orchiectomy is needed for a confirmed testicular mass by ultrasound after professional evaluation. For detail, ask your surgeon-urologist timely. Best wish ...