Risk factors and treatment outcomes of 239 patients with testicular granulosa cell tumors: a systematic review of published case series data

PURPOSE: Testicular granulosa cell tumors (tGrCT) are rare sex cord-stromal tumors. This review aims to synthesize the available evidence regarding the clinical presentation and clinicopathological characteristics, treatment and outcomes. METHODS: We conducted a systematic literature search using the most important research databases. Whenever feasible, we extracted the data on individual patient level. RESULTS: From 7863 identified records, we included 88 publications describing 239 patients with tGrCT. The majority of the cases were diagnosed with juvenile tGrCT (166/239, 69%), while 73/239 (31%) patients were diagnosed with adult tGrCT. Mean age at diagnosis was 1.5 years (± 5 SD) for juvenile tGrCT, and 42 years (± 19 SD) for adult tGrCT. Information on primary treatment was available in 231/239 (97%), of which 202/231 (87%) were treated with a radical orchiectomy and 20/231 (9%) received testis sparing surgery (TSS). Local recurrence after TSS was observed in 1/20 (5%) cases. Metastatic disease was never observed in men with juvenile tGrCT but in 7/73 (10%) men with adult tGrCT. In 5/7 men with metastatic tGrCT, metastases were diagnosed at initial staging, while 2/7 patients developed metastases after 72 and 121 months of follow-up, respectively. Primary site of metastasis is represented by the retroperitoneal lymph nodes, but other sites including lungs, liver, bone and inguinal lymph nodes can also be affected. In comparison with non-metastatic adult tGrCT, men with metastatic adult tGrCT had significantly larger primary tumors (70 vs 24 mm, p 0.001), and were more likely to present with angiolymphatic invasion (57% vs 4%, p 0.002) or gynecomastia (29% vs 3%, p 0.019). In five out of seven men with metastatic disease, resection of metastases or platinum-based chemotherapy led to complete remission. CONCLUSION: Juvenile tGrCT represent a benign entity whereas adult tGCTs have metastatic potential. Tumor size, presence of angiolymphatic invasion or gynecomastia represent risk factors for metastatic disease. The published literature supports the use of testis sparing surgery but there is only limited experience with adjuvant therapies. In the metastatic setting, the reviewed literature suggests that aggressive surgical and systemic treatment might cure patients. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00432-020-03326-3) contains supplementary material, which is available to authorized users.