Teratocarcinomas

ALSO KNOWN AS: Teratomas

RELATED CONDITIONS: Germ-cell tumors, nonseminomatous germ-cell tumors (NSGCTs), choriocarcinomas, yolk sac tumors, seminomas, embryonal cell carcinomas, dermoid cysts

DEFINITION: Teratocarcinomas are malignant testicular cancers whose cells are derived from primordial germ cells (spermatozoa precursor cells). They are a mixed tumor composed of an embryonal carcinoma formed from a teratoma's epithelial cells. Teratomas are tumors, typically benign and usually seen in prepubescent boys but also found in the ovary (dermoid cyst), in which cells are derived from all three primitive embryonic tissue layers. Teratocarcinomas contain embryonic stem cells in addition to these cells.

Risk factors: One of the risk factors for developing a teratocarcinoma is undescended testes (cryptorchidism) during infancy. Anomalies in testicular development, such as that found in Klinefelter syndrome, may increase the risk of malignancy. Family history, age of descent or correction, location, single or bilateral undescended testes, premature birth, and previous history of testicular cancer have also been implicated.

Etiology and the disease process: The exact mechanisms by which teratocarcinomas develop remain unknown. Studies suggest that primordial spermatozoa cells (gonocytes) in the seminiferous tubules of the testes retain their embryonic characteristics of being able to differentiate into different mature tissues, as well as divide uncontrollably when testicular development is interrupted.

Incidence: There are about 9,760 cases of testicular cancer reported in the United States per year. Teratocarcinoma make up 25 to 30 percent of testicular tumors.

Symptoms: Symptoms may include an often painless, palpable mass within the scrotal area. The mass may also be firm and, at times, fixed. Discovery of the mass may be incidental, with no other signs of disease present.

Screening and diagnosis: Diagnosis is primarily clinical. If twisting of the testicle or its blood supply is suspected (causing discoloration and pain), Doppler ultrasound is done to assess blood flow as well as visualize the mass. Abdominal computed tomography (CT) or magnetic resonance imaging (MRI) is carried out to look for spread outside the scrotum.

Treatment and therapy: Surgical resection of the entire tumor; chemotherapy with cisplatin, bleomycin, and vinblastine; and irradiation are the treatments of choice. In the mid-2020s, medical researchers began investigating the effectiveness of cellular therapies in treating solid tumors like teratocarcinoma. Additionally, combinations of chemotherapy drugs proved effective in treating teratocarcinoma. 

Prognosis, prevention, and outcomes: Prognosis is generally excellent with optimal treatment. The five-year survival rate for patients with teratocarcinomas is 93 percent. However, infertility may occur and should be understood by the patient as a possible side effect of therapy.

Bibliography

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Bulić-Jakus, Floriana et al. “Of Mice and Men: Teratomas and Teratocarcinomas.” Collegium Antropologicum, vol. 30.4, 2006, pp. 921-4.

Damjanov, Ivan, and Peter W. Andrews. "The Terminology of Teratocarcinomas and Teratomas." Nature Biotechnology, vol. 25, no. 11, 2007, p. 1212, doi.org/10.1038/nbt1107-1212a. Accessed 23 June 2024.

“Facts About Testicular Cancer - Testicular Cancer Statistics.” American Cancer Society, 17 Jan. 2024, www.cancer.org/cancer/types/testicular-cancer/about/key-statistics.html. Accessed 23 June 2024.

Garcia, Cristina C., et al. "Survival of Testicular Pure Teratoma Vs. Mixed Germ Cell Tumor Patients in Primary Tumor Specimens across All Stages." Cancers, vol. 15, no. 3, 2023, doi.org/10.3390/cancers15030694. Accessed 23 June 2024.

McHugh, Deaglan J., et al. "Testicular Cancer in 2023: Current Status and Recent Progress." CA: A Cancer Journal for Clinicians, vol. 74, no. 2, 2024, pp. 167-186, doi.org/10.3322/caac.21819. Accessed 23 June 2024.

“Testicular Cancer Treatment (PDQ®).” National Cancer Institute, 15 Mar. 2024, www.cancer.gov/types/testicular/hp/testicular-treatment-pdq. Accessed 23 June 2024.