The fate of paratesticular masses: 13 years' experience in a tertiary referral centre.

Objective: Paratesticular neoplasms exhibit different behaviours, depending on the embryological tissue of origin. Treatment modalities can depend on the differential diagnosis. The aim of this study is to present the clinical, morphological and histopathological features of patients with paratesticular masses and their follow-ups and is intended to increase awareness of the issues.

Methodology: We included 31 excisions of paratesticular masses, after radiological diagnosis as paratesticular mass in our hospital between 2007-2020. Information on treatment modalities, tumour recurrence, metastasis, and survival rates were obtained from hospital archives. All patients were evaluated by taking patients' history, physical examination, scrotal ultrasound, chest radiography, and serum tumour markers. Treatment modality was selected according to intraoperative findings. Haematoxylin-eosin sections were examined, and immunohistochemical analyses were performed for smooth muscle actin, desmin, Ki67, CD34, S100, and myogenin. Ten high-power fields were counted to document Ki67 and p53 nuclear positivity rates.

Results: A total of 31 operations were performed with recurrence in three patients. Histomorphological and immunohistochemical examination revealed eleven malignant masses; eight rhabdomyosarcomas, a leiomyosarcoma, a liposarcoma and a large B cell lymphoma. Other excised masses were benign and infective lesions.

Conclusion: Paratesticular masses are heterogeneous tumours that follow different clinical courses. Clinicians must be aware of this histological diversity in order to plan a treatment pathway. This study is one of the largest published series, with a long follow-up period. It shows that the most critical features in determining prognosis are histopathological subtype and tumour grade.