A tumor comprising of different types of tissues (such as hair, muscle, bone, etc.) is known as a teratoma. It is a type of germ cell (cells that make sperm or eggs) tumor. When these germ cells have rapid cancerous growth, then such a teratoma is called a malignant teratoma. We have studied the differences between gonadal and extra-gonadal malignant teratomas and the effects of chemotherapy in both genders.

Methods: The samples of 3799 male and 1832 female patients with malignant teratoma samples, between the ages of 1 and 85+ years, were selected from the years 1973 to 2014. Trends in incidence, estimated prevalence, incidence rates, and frequency were calculated in gonadal and extra-gonadal tumors with age adjustment. The fiveyear observed, expected, and relative survival rates were analyzed to study the prognosis.

The registry used in our study was the SEER 9 registries Custom Data (with additional treatment fields), Nov 2016 Submission (1973-2014) < Katrina/Rita Population Adjustment> - Linked to County Attributes -Total United States, 1969-2015 Counties, National Cancer Institute, DCCPS (Division of Cancer Control and Population Sciences), Surveillance Research Program, released April 2017, based on the November 2016 submission.

The registry used in our study was the SEER 9 registries Custom Data (with additional treatment fields), Nov 2016 Submission (1973-2014) < Katrina/Rita Population Adjustment> - Linked to County Attributes -Total United States, 1969-2015 Counties, National Cancer Institute, DCCPS (Division of Cancer Control and Population Sciences), Surveillance Research Program, released April 2017, based on the November 2016 submission.