LAUSR

Background: The aim of this study was to examine clinical/pathological characteristics, prognosis and tendency to metastasis of mixed germ cell tumours (MGCTs) that contain a seminoma component. Methods: A total of 111 MGCT cases between 2008 and 2018 were retrospectively enrolled. The patients were divided into 2 groups according to the absence (group 1) or presence (group 2) of seminoma component in MGCTs. Patients’ age, complaints at admission to our clinic, primary tumour localization, primary tumour size, preoperative testicular tumour markers, MGCT histopathological components and percentages, lymphovascular invasion, pathological tumour stage, postoperative testicular tumour markers, presence of lymph node involvement in abdominal tomography, lung metastasis based on thorax tomography, clinical tumour stage, adjunctive therapies performed, state of recurrence and survival were compared in 2 groups. Results: The mean age of the patients was 24.51 ± 4.79 years. The mean age, initial complaint rates, primary tumour size, postoperative testicular tumour markers, presence of lymphovascular invasion, presence of lymph node involvement and lung metastasis were found to be higher in group 2 than in group 1, although these differences were not statistically significant. Especially, it was found that a seminoma component rate of 30% and higher had a higher tendency for a poor prognosis. Conclusion: Although the word “seminoma” may be initially interpreted as an indication of good prognosis, a seminoma component in MGCTs is actually not a good prognostic factor. MGCTs that contain a seminoma component (especially 30% and higher) can have a higher tendency for occult metastatic disease.