Advances in the Biosciences, Volume 91: Germ Cell Tumours III documents the proceedings of the Third Germ Cell Tumor Conference held in Leeds, UK on September 8-10, 1993. This book focuses on germ cell tumors, which can be cancerous or non-cancerous tumors that normally occur inside the gonads. The topics discussed include the embryological mechanisms of maldescent and tumorigenesis; epidemiology of cryptorchidism; simultaneous bilateral testicular tumors; and mediastinal germ cell tumors. The classification of germ cell tumors; role of positron emission tomography in the assessment of germ cell tumors; chemotherapy of seminoma; and prognostic factors in disseminated non-seminomatous testicular cancer are also elaborated in this text. This publication is intended for medical students and individuals interested in germ cell tumors.