Most treatments involve some combination of surgery and chemotherapy. Treatment with cisplatin, etoposide, and bleomycin has been described.

Before modern chemotherapy, this type of neoplasm was highly lethal, but the prognosis has significantly improved since.

When endodermal sinus tumors are treated promptly with surgery and chemotherapy, fatal outcomes are exceedingly rare.

The usual treatment is surgery. The surgery usually is a fertility-sparing unilateral salpingo-oophorectomy. For malignant tumours, the surgery may be radical and usually is followed by adjuvant chemotherapy, sometimes by radiation therapy. In all cases, initial treatment is followed by surveillance. Because in many cases Sertoli–Leydig cell tumour does not produce elevated tumour markers, the focus of surveillance is on repeated physical examination and imaging. Given that many cases of Sertoli–Leydig cell tumor of the ovary are hereditary, referral to a clinical genetics service should be considered.

The prognosis is generally good as the tumour tends to grow slowly and usually is benign: 25% are malignant. For malignant tumours with undifferentiated histology, prognosis is poor.

Women with benign germ cell tumors such as mature teratomas (dermoid cysts) are cured by ovarian cystectomy or oophorectomy. In general, all patients with malignant germ cell tumors will have the same staging surgery that is done for epithelial ovarian cancer. If the patient is in her reproductive years, an alternative is unilateral salpingoophorectomy, while the uterus, the ovary, and the fallopian tube on the opposite side can be left behind. This isn't an option when the cancer is in both ovaries. If the patient has finished having children, the surgery involves complete staging including salpingoophorectomy on both sides as well as hysterectomy.

Most patients with germ cell cancer will need to be treated with combination chemotherapy for at least 3 cycles. The chemotherapy regimen most commonly used in germ cell tumors is called PEB (or BEP), and consists of bleomycin, etoposide, a platinum-based antineoplastic (cisplatin).

The 1997 International Germ Cell Consensus Classification is a tool for estimating the risk of relapse after treatment of malignant germ cell tumor.

A small study of ovarian tumors in girls reports a correlation between cystic and benign tumors and, conversely, solid and malignant tumors. Because the cystic extent of a tumor can be estimated by ultrasound, MRI, or CT scan before surgery, this permits selection of the most appropriate surgical plan to minimize risk of spillage of a malignant tumor.

Access to appropriate treatment has a large effect on outcome. A 1993 study of outcomes in Scotland found that for 454 men with non-seminomatous (non-germinomatous) germ cell tumors diagnosed between 1975 and 1989, 5-year survival increased over time and with earlier diagnosis. Adjusting for these and other factors, survival was 60% higher for men treated in a cancer unit that treated the majority of these men, even though the unit treated more men with the worst prognosis.

Choriocarcinoma of the testicles has the worst prognosis of all germ cell cancers

GCNIS is generally treated by radiation therapy and/or orchiectomy. Chemotherapy used for metastatic germ cell tumours may also eradicate GCNIS.

Embryonal carcinoma is a relatively uncommon type of germ cell tumour that occurs in the ovaries and testes.

Serous tumours are part of the surface epithelial-stromal tumour group of ovarian neoplasms, which derive from Mullerian epithelium.

They are common neoplasms with a strong tendency to bilaterality, and they account for 50% of all ovarian tumours.

Sixty percent are benign (cystadenoma), 10% are borderline and 30% are malignant (cystadenocarcinoma).

Wide excision is the treatment of choice, although attempting to preserve hearing. Based on the anatomic site, it is difficult to completely remove, and so while there is a good prognosis, recurrences or persistence may be seen. There is no metastatic potential. Patients who succumb to the disease, usually do so because of other tumors within the von Hippel-Lindau complex rather than from this tumor.

10-year survival rates for mucinous tumors is excellent in the absence of invasion.

In the case of borderline tumors confined to the ovary and malignant tumors without invasion, the survival rates are 90% or greater. In invasive mucinous cystadenocarcinomas, the survival is approximately 30%

It is associated with hormone replacement therapy (estrogen). The risk is higher in white women than other ethnicities, incidence, prevalence, age distribution, and sex ratio

Aggressive surgical removal of the tumor and any enlarged sublumbar lymph nodes is essential for treatment of the tumor and associated hypercalcaemia. There is a high recurrence rate, although removal of lymph nodes with metastasis may improve survival time. Radiation therapy and chemotherapy may be helpful in treatment. Severe hypercalcaemia is treated with aggressive IV fluid therapy using sodium chloride and medications such as loop diuretics (increased kidney excretion of calcium) and aminobisphosphonates (decreased calcium release from bones). A poorer prognosis is associated with large tumor size (greater than 10 cm), hypercalcaemia, and distante metastasis. Early, incidental diagnosis of small anal sac masses may lead to a better prognosis with surgery alone (ongoing study).

For malignant teratomas, usually, surgery is followed by chemotherapy.

Teratomas that are in surgically inaccessible locations, or are very complex, or are likely to be malignant (due to late discovery and/or treatment) sometimes are treated first with chemotherapy.

This is a very rare tumor, since only about 1 in 35,000 to 40,000 people have VHL, of whom about 10% have endolymphatic sac tumors. Patients usually present in the 4th to 5th decades without an gender predilection. The tumor involves the endolymphatic sac, a portion of the intraosseous inner ear of the posterior petrous bone.

Wide, radical, complete surgical excision is the treatment of choice, with free surgical margins to achieve the best outcome and lowest chance of recurrence. Radiation is only used for palliation. In general, there is a good prognosis, although approximately 50% of patients die from disease within 3–10 years of presentation.

Surface epithelial-stromal tumors are a class of ovarian neoplasms that may be benign or malignant. Neoplasms in this group are thought to be derived from the ovarian surface epithelium (modified peritoneum) or from endometrial or Fallopian tube (tubal) tissue. Tumors of this type are also called ovarian adenocarcinoma. This group of tumors accounts for 90% to 95% of all cases of ovarian cancer. Serum CA-125 is often elevated but is only 50% accurate so it is not a useful tumor marker to assess the progress of treatment.

Ovarian tumors, or ovarian neoplasms, are tumors arising from the ovary. They can be benign or malignant (ovarian cancer).

In light of the ethical issues surrounding the source of human stem cells, teratomas are being looked at as an alternative source for research because they lack the potential to grow into functional human beings.

Polyembryoma is a rare, very aggressive form of germ cell tumor usually found in the ovaries. Polyembryoma has features of both yolk sac tumour and undifferentiated teratoma/embryonal carcinoma, with a characteristic finding of embryoid bodies lying in a loose mesenchymal stroma.

It has been found in association with Klinefelter syndrome.

Germinomas, like several other types of germ cell tumor, are sensitive to both chemotherapy and radiotherapy. For this reason, treatment with these methods can offer excellent chances of longterm survival, even cure.

Although chemotherapy can shrink germinomas, it is not generally recommended alone unless there are contraindications to radiation. In a study in the early 1990s, carboplatinum, etoposide and bleomycin were given to 45 germinoma patients, and about half the patients relapsed. Most of these relapsed patients were then recovered with radiation or additional chemotherapy.

Germ cell neoplasia in situ, abbreviated GCNIS, represents the precursor lesion for many types of testicular germ cell tumors. As the name suggests, it represents a neoplastic process of germ cells that is confined to the spermatogonial niche.

The term GCNIS was introduced with the 2016 edition of the WHO classification of urological tumours. It replaces the previous term intratubular germ cell neoplasia, abbreviated ITGCN or IGCN and also known as testicular intratubular germ cell neoplasia and intratubular germ cell neoplasia of the testis. GCNIS more accurate describes the lesion as it arises between the basement membrane and Sertoli cells (the cells that 'nurse' the developing germ cell). The common, unspecified variant of the entity was once considered to be a carcinoma in situ although the term "carcinoma "in situ"" is now largely historical as it is not an accurate description of the process.

Brenner tumors are an uncommon subtype of the surface epithelial-stromal tumor group of ovarian neoplasms. The majority are benign, but some can be malignant.

They are most frequently found incidentally on pelvic examination or at laparotomy. Brenner tumours very rarely can occur in other locations, including the testes.

Transitional cell carcinoma of the ovary, abbreviated TCC of the ovary, is a rare type of ovarian cancer that has an appearance similar to urothelial carcinoma (also known as transitional cell carcinoma).

Fertility subsequent to treatment of surface epithelial-stromal tumors depends mainly on histology and initial

staging to separate it into early borderline (or more benign) versus advanced stages of borderline (or more malignant). Conservative management (without bilateral oophorectomy) of early stage borderline tumors have been estimated to result in chance of over 50% of spontaneous pregnancy with a low risk of lethal recurrence of the tumor (0.5%). On the other hand, in cases of conservative treatment in advanced stage borderline tumors, spontaneous pregnancy rates have been estimated to be 35% and the risk of lethal recurrence 2%.

Prognosis and treatment is the same as for the most common type of ovarian cancer, which is epithelial ovarian cancer.

The median survival of primary peritoneal carcinomas is usually shorter by 2–6 months time when compared with serous ovarian cancer. Studies show median survival varies between 11.3–17.8 months. One study reported 19-40 month median survival (95% CI) with a 5-year survival of 26.5%.

Elevated albumin levels have been associated with a more favorable prognosis.

Sertoli–Leydig cell tumour is a group of tumours composed of variable proportions of Sertoli cells, Leydig cells, and in the case of intermediate and poorly differentiated neoplasms, primitive gonadal stroma and sometimes heterologous elements.

Sertoli–Leydig cell tumour is a member of the sex cord-stromal tumour group of ovarian and testicular cancers. The tumour is rare, comprising less than 1% of testicular tumours. While the tumour can occur at any age, it occurs most often in young adults. Recent studies have shown that many cases of Sertoli–Leydig cell tumor of the ovary are caused by germline mutations in the "DICER1" gene. These hereditary cases tend to be younger, often have a multinodular thyroid goiter and there may be a personal or family history of other rare tumors such as pleuropulmonary blastoma, Wilms tumor and cervical rhabdomyosarcoma.

Closely related terms include arrhenoblastoma and androblastoma. Both terms are classified under Sertoli–Leydig cell tumour in MeSH.