Rare intrascrotal tumors in a tertiary cancer center: A retrospective case series.

415 Background: Given their rarity, the literature on non-germ cell testicular tumors and paratesticular malignancies is still scarce. The objective of this study is to describe clinical and pathological features, as well as treatment patterns and outcomes, of patients with non-germ cell intrascrotal malignancies. Methods: Patients (pts) with benign or malignant non-germ cell intrascrotal tumors who were older than 18 years-old were deemed eligible. Electronic health records (EHR) were reviewed to assess pts clinical features, and disease characteristics and outcomes. Descriptive statistics was used to report data. RECIST 1.1 was used to determine radiological response to treatment. Time-to-event variables were estimated by the Kaplan-Meier method. Results: EHR of 885 pts with a primary diagnosis of ICD-10 C62 treated in a tertiary cancer center from January 2009 to June 2020 were reviewed for eligibility. 29 pts fulfilled eligibility criteria (Sertoli cell tumors, N = 3; Leydig cell tumors, N = 6; granulosa cell tumor, N = 1; testicular tumor of the androgenital syndrome, N = 1; mesotheliomas, N = 3; liposarcomas, N = 3; leiomyosarcomas N = 2; rhabdomyosarcomas, N = 3; spindle cell sarcomas, N = 3; lymphomas, N = 2; carcinoma of the rete testis, N = 1; primary neuroendocrine tumor of the testis, N = 1). The majority of pts (N = 25) had non-metastatic disease at diagnosis, and underwent upfront orchiectomy. The remaining four patients had metastatic disease at diagnosis (lymphoma, N = 1; sarcomas, N = 3), all positive for lymph node (LN) involvement; one with concurrent visceral metastasis. Six other pts posteriorly developed metastatic disease after a median follow-up of 13 months (IQR: 5.8–33.1 months) (Leydig tumor, N = 1; mesothelioma, N = 2; sarcomas, N = 3). The most common metastatic sites were LN (N = 8, 80%), lung (N = 4, 40%), bone (N = 3, 30%), adrenal gland (N = 2, 20%), peritoneum (N = 1, 10%), and skin (N = 1, 10%). Nine pts (90%) received systemic treatment: vincristine, doxorubicin and cyclophosphamide for rhabdomyosarcomas (N = 3), cisplatin plus pemetrexed for mesotheliomas (N = 2), doxorubicin for liposarcomas (N = 2), doxorubicin plus ifosfamide for liposarcoma (N = 1) and doxorubicin, vincristine, cyclophosphamide, and prednisone plus rituximab for lymphoma (N = 1). Of those, 2 pts achieved partial response and 2 had stable disease. Metastasectomy of a single lung metastasis was performed in a patient with metastatic Leydig cell tumor. Median overall survival was 51.2 and 24.5 months for patients with localized and metastatic disease, respectively. Conclusions: Paratesticular and non-germ cell testicular tumors are extremely rare entities with relatively good prognosis if treated at early stages depending on the underlying histology. Most metastatic disease cases were due to paratesticular sarcomas.