A 26-year-old male with no past medical history had presented with an acute history of back pain and leg swelling. Initial investigations revealed extensive left-sided iliofemoral deep vein thrombosis (DVT). A CT venogram performed to delineate its central extent revealed a large retroperitoneal soft tissue mass, encasing the upper inferior vena cava (IVC) and right ureter, with right-sided hydronephrosis. There were extensive thromboses of the lower IVC, iliac, common femoral, and left femoral veins. A further staging CT scan revealed no other sites of disease.
Lymphoma was initially considered the most likely diagnosis and tissue confirmation was sought via ultrasound-guided biopsy of the retroperitoneal mass. However, histopathology and immunohistochemistry appearances favored a seminoma. An ultrasound examination of the testes demonstrated a scar in the lower pole of the right testicle, and subsequent orchiectomy confirmed the diagnosis. He received chemotherapy consisting of bleomycin, etoposide, and cisplatin, which was well tolerated.
Several attempts at bypassing the obstructed right collecting system were unsuccessful, despite the excellent response in the size of the tumor after chemotherapy. A subsequent renal dimercaptosuccinic acid (DMSA) scan showed poor function in the right kidney, likely compounded by chemotherapy. Currently, the patient remains well with stable renal function and is awaiting a right nephrectomy.
Burned-out testicular tumors are relatively rare and poorly understood. They are thought to occur secondary to the tumor outgrowing its blood supply, or an immune-mediated response by the host.1,2 Since the primary tumor is often not palpable, the patient will often present with symptoms of metastatic disease, commonly abdominal or back pain. Therefore, GCTs should always be considered when a retroperitoneal mass of unknown origin is discovered, and urgent testicular ultrasound should be obtained. Orchiectomy combined with chemotherapy remains the mainstay of treatment,3 although data regarding long-term outcomes when compared to non-regressed and extragonadal GCTs is lacking and further longitudinal studies would be useful.
This case demonstrates that occult testicular germ cell tumors may occasionally present as retroperitoneal masses. While usually more straightforward to diagnose when a testis is clinically abnormal, the association between a retroperitoneal mass and its testicular origin may not be evident when there are no symptoms or any abnormalities on testicular examination. Therefore, a high index of suspicion is necessary to arrive at a timely and accurate diagnosis.
Written by: Deepak Batura, MBBS, MS, MCh, FRCS, Consultant Urological Surgeon, London North West University Healthcare NHS Trust, London, United Kingdom
- Johnson, Kate, and Bryan Brunet. "Brain metastases as presenting feature in'burned Out'testicular germ cell tumor." Cureus 8, no. 4 (2016).
- Mosillo, Claudia, Simone Scagnoli, Giulia Pomati, Salvatore Caponnetto, Maria Laura Mancini, Mario Bezzi, Enrico Cortesi, and Alain Gelibter. "Burned-out testicular cancer: really a different history." Case reports in oncology 10, no. 3 (2017): 846-850.
- Bokemeyer, C., C. Kollmannsberger, S. Stenning, J. T. Hartmann, A. Horwich, C. Clemm, A. Gerl et al. "Metastatic seminoma treated with either single agent carboplatin or cisplatin-based combination chemotherapy: a pooled analysis of two randomised trials." British journal of cancer 91, no. 4 (2004): 683-687.