Testicular cancers can have diverse histological types. More than 90 percent of all testicular cancers arise in special cells called the “germ cells”, according to the American Cancer Society. These cells are the sperm producing cells in the testis. Primary testicular tumors are classified as seminomas, non-seminomas, or mixed germ cell tumors. The non-seminomas comprise types like the embryonal carcinoma, yolk sac carcinoma, choriocarcinoma, and teratoma. Most tumors are a mix of two or more different components.
Testicular neoplasms also include stromal tumors. These include the Leydig cell tumors and Sertoli cell tumors.
Lastly, secondary tumors may also develop in the testes. The most common primary cancer to metastasize to the testis is leukemia. Lymphomas may also result in secondary neoplasms in the testis. Other tumors that may spread to the testis include the carcinomas of the prostate, lung, skin (melanoma), kidney, and other organs.
For secondary neoplasm of the testis, you report code 198.82 (Secondary malignant neoplasm of genital organs). The corresponding ICD-10-CM code is C79.82 (Secondary malignant neoplasm of genital organs).