Burned-Out Testicular Tumor Presenting as a Retroperitoneal Mass: A Case Report

Spontaneous primary tumor regression, or burned-out tumors, refers to the presence of a metastatic tumor with the histological regression of the primary lesion. The burned-out phenomenon has been reported in various malignancies, with testicular germ cell tumors (GCTs) accounting for a significant share of these cases. However, burned-out testicular tumors are a rare clinical phenomenon and are generally difficult to diagnose, as there is no evidence of primary testicular cancer. Here, we describe the case of a 42-year-old male who presented to our hospital complaining of right abdomen and groin pain for several months. On physical exam, the patient had normal genital and rectal exams. An abdominal-pelvic computed tomography (CT) scan of his abdomen and pelvis revealed a large retroperitoneal mass with radiographic characteristics of a sarcoma. Given his groin pain, the patient had a testicular ultrasound, which revealed scar tissue in the right testicle. His testicular tumor markers showed elevated β-human chorionic gonadotropin (β-hCG) and lactate dehydrogenase (LDH) but normal α-fetoprotein (AFP). He underwent right radical inguinal orchiectomy, with pathologic examination of the testicle revealing a burned-out testicular tumor. The patient was then treated with four cycles of bleomycin, etoposide, and cisplatin (BEP). His post-treatment tumor markers were normalized; however, his abdomen-pelvic CT scan showed a persistent mass. The patient underwent retroperitoneal lymph node dissection (RPLND) with the removal of 12 lymph nodes. However, pathologic evaluation of the lymph nodes revealed no evidence of neoplastic cells. The patient has remained disease-free after five years of follow-up. This report highlights the potential of burned-out testicular tumors in young and middle-aged men presenting with a retroperitoneal mass. Furthermore, it underscores the importance of obtaining testicular ultrasound in these patients to rule out regressed testicular tumors.