Metastatic germ cell tumour in effusion cytology

Background Germ cell tumours infrequently metastasise to body cavities, where early detection on fluid samples is possible and can spearhead early treatment and survival. Materials and methods A total of seven cases of metastatic germ cell tumours were retrieved out of 7500 effusion samples received for cytopathological examination from 2015 to 2021. Detailed cytological features of metastatic germ cell tumours in effusion samples were studied, along with a correlation between clinical, radiological, and histopathological features. Results A total of seven cases of metastatic germ cell tumours were analysed in effusion samples which included dysgerminoma (2), immature teratoma (2), yolk sac tumour (1), embryonal carcinoma (1), and mixed germ cell tumour (1). The smears showed predominantly discrete or loose clusters of cells. The cells with round nuclei and prominent nucleoli were helpful in detecting dysgerminoma and yolk sac tumours. Immature teratoma showed tiny groups of small cells and mature squamous cells. Serum tumour markers were raised in the majority of cases. Conclusion Metastatic germ cell tumours in effusion are uncommon, but detailed clinical history, including serum markers and characteristic cytological features, are helpful in their diagnosis.