Uterine sarcoma are rare, out of all malignancies of the uterine body only about 4% will be uterine sarcomas. Generally, the cause of the lesion is not known, however patients with a history of pelvic radiation are at higher risk. Most tumors occur after menopause.

Women who take long-term tamoxifen are at higher risk.

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%

Alcohol consumption does not appear to be related to ovarian cancer. Other factors that have been investigated, such as smoking, low levels of vitamin D in the blood, presence of inclusion ovarian cysts, and infection with human papilloma virus (the cause of some cases of cervical cancer), have been disproven as risk factors for ovarian cancer. The carcinogenicity of perineal talc is controversial, because it can act as an irritant if it travels through the reproductive tract to the ovaries. Case-control studies have shown that use of perineal talc does increase the risk of ovarian cancer, but using talc more often does not create a greater risk. Use of talc elsewhere on the body is unrelated to ovarian cancer. Sitting regularly for prolonged periods is associated with higher mortality from epithelial ovarian cancer. The risk is not negated by regular exercise, though it is lowered.

Increased age (up to the 70s) is a risk factor for epithelial ovarian cancer because more mutations in cells can accumulate and eventually cause cancer. Those over 80 are at slightly lower risk.

Smoking tobacco is associated with a higher risk of mucinous ovarian cancer; after smoking cessation, the risk eventually returns to normal.A diet high in animal fats may be associated with ovarian cancer, but the connection is unclear. Diet seems to play a very small role, if any, in ovarian cancer risk.

Higher levels of C-reactive protein are associated with a higher risk of developing ovarian cancer.

Industrialized nations, with the exception of Japan, have high rates of epithelial ovarian cancer, which may be due to diet in those countries. Caucasian are at a 30–40% higher risk for ovarian cancer when compared to Black and Hispanic people, likely due to socioeconomic factors; white women tend to have fewer children and different rates of gynecologic surgeries that affect risk for ovarian cancer.

Cohort studies have found a correlation between dairy consumption and ovarian cancer, but case-control studies do not show this correlation. There is mixed evidence regarding the effect of red meat and processed meat in ovarian cancer.

Tentative evidence suggests that talc, pesticides, and herbicides increase the risk of ovarian cancer. The American Cancer Society notes that as of now, no study has been able to accurately link any single chemical in the environment, or in the human diet, directly to mutations that cause ovarian cancer.

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

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%.

Some investigators suggest that this distribution arises as a consequence of abnormal migration of germ cells during embryogenesis. Others hypothesize a widespread distribution of germ cells to multiple sites during normal embryogenesis, with these cells conveying genetic information or providing regulatory functions at somatic sites.

Extragonadal germ cell tumors were thought initially to be isolated metastases from an undetected primary tumor in a gonad, but it is now known that many germ cell tumors are congenital and originate outside the gonads. The most notable of these is sacrococcygeal teratoma, the single most common tumor diagnosed in babies at birth.

Of all anterior mediastinal tumors, 15–20% are germ cell tumors of which approximately 50% are benign teratomas.

A malignant mixed Müllerian tumor, also known as malignant mixed mesodermal tumor, MMMT and carcinosarcoma, is a malignant neoplasm found in the uterus, the ovaries, the fallopian tubes and other parts of the body that contains both carcinomatous (epithelial tissue) and sarcomatous (connective tissue) components. It is divided into two types, homologous (in which the sarcomatous component is made of tissues found in the uterus such as endometrial, fibrous and/or smooth muscle tissues) and a heterologous type (made up of tissues not found in the uterus, such as cartilage, skeletal muscle and/or bone). MMMT account for between two and five percent of all tumors derived from the body of the uterus, and are found predominantly in postmenopausal women with an average age of 66 years. Risk factors are similar to those of adenocarcinomas and include obesity, exogenous estrogen therapies, and nulliparity. Less well-understood but potential risk factors include tamoxifen therapy and pelvic irradiation.

Since gestational choriocarcinoma (which arises from a hydatidiform mole) contains paternal DNA (and thus paternal antigens), it is exquisitely sensitive to chemotherapy. The cure rate, even for metastatic gestational choriocarcinoma, is around 90–95%.

At present, treatment with single-agent methotrexate is recommended for low-risk disease, while intense combination regimens including EMACO (etoposide, methotrexate, actinomycin D, cyclosphosphamide and vincristine (Oncovin) are recommended for intermediate or high-risk disease.

Hysterectomy (surgical removal of the uterus) can also be offered to patients > 40 years of age or those for whom sterilisation is not an obstacle. It may be required for those with severe infection and uncontrolled bleeding.

Choriocarcinoma arising in the testicle is rare, malignant and highly resistant to chemotherapy. The same is true of choriocarcinoma arising in the ovary. Testicular choriocarcinoma has the worst prognosis of all germ-cell cancers.

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

The uterine sarcomas form a group of malignant tumors that arises from the smooth muscle or connective tissue of the uterus.

For surface epithelial-stromal tumors, the most common sites of metastasis are the pleural cavity (33%), the liver (26%), and the lungs (3%).

Benign tumors of the ovary include ovarian cysts, such as borderline tumor cysts.

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).

Choriocarcinoma of the placenta during pregnancy is preceded by:

- hydatidiform mole (50% of cases)

- spontaneous abortion (20% of cases)

- ectopic pregnancy (2% of cases)

- normal term pregnancy (20–30% of cases)

- hyperemesis gravidarum

Rarely, choriocarcinoma occurs in primary locations other than the placenta; very rarely, it occurs in testicles. Although trophoblastic components are common components of mixed germ cell tumors, pure choriocarcinoma of the adult testis is rare. Pure choriocarcinoma of the testis represents the most aggressive pathologic variant of germ cell tumors in adults, characteristically with early hematogenous and lymphatic metastatic spread. Because of early spread and inherent resistance to anticancer drugs, patients have poor prognosis. Elements of choriocarcinoma in a mixed testicular tumor have no prognostic importance.

Choriocarcinomas can also occur in the ovaries.

There is debate over the naming of MMMT; the term carcinosarcoma was formerly used to describe lesions with homologous tumors, and "malignant mixed Müllerian tumor" or "mixed mesodermal tumor" was used to describe heterologous tumors. While "carcinosarcoma" now considered standard, "malignant mixed Müllerian tumor" has a lengthy history within gynecological literature and is expected to continue to be used. The naming issue to a certain extent reflects histological characteristics and development of the tumors, in which the different types of tissues are believed to either develop separately and join into a single mass (the "collision" theory), that an adenocarcinoma stimulates the stroma to create a tumor (the "composition" theory), or that the tumor is the result of a stem cell that differentiates into different cell types (the "combination" theory). "Collision" tumors are normally easily recognized and not considered true MMMTs; the "combination" theory is most widely held, and is due to evidence that the tumors develop from a single line of cells, developing in a fashion similar to the fundus of the uterus from the Müllerian duct - first from a stem cell into a population of cells, that then differentiates into epithelial and stromal components.

There is evidence that some tumors are better explained by the composition theory, due to the aggressive nature of the epithelial cells involved which tend to metastasize much more readily than the sarcomal component. The behavior of MMMT overall is more related to the type and grade of the epithelium than the sarcoma, which suggests the sarcomal portion is an atypical "bystander" than primary driver of the tumor. Despite this, when purely endometrial tumors are compared to MMMTs, the MMMT tumor tends to have a worse prognosis.

The prognosis is determined primarily by the cancer stage. Most tumours are discovered at an early stage and have a good prognosis, especially when compared to uterine carcinosarcoma. Five year survival for stage I and stage III tumours is approximately 80% and 50% respectively.

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.

The average age at time of EIN diagnosis is approximately 52 years, compared to approximately 61 years for carcinoma. The timeframe and likelihood of EIN progression to cancer, however, is not constant amongst all women. Some cases of EIN are first detected as residual premalignant disease in women who already have carcinoma, whereas other EIN lesions disappear entirely and never lead to cancer. For this reason, treatment benefits and risks must be individualized for each patient under the guidance of an experienced physician.

Risk factors for development of EIN and the endometrioid type of endometrial carcinoma include exposure to estrogens without opposing progestins, obesity, diabetes, and rare hereditary conditions such as hereditary nonpolyposis colorectal cancer. Protective factors include use of combined oral contraceptive pills (low dose estrogen and progestin), and prior use of a contraceptive intrauterine device.

Uterine adenosarcoma, also adenosarcoma of the uterus, and Müllerian adenosarcoma of the uterus, is an uncommon form of cancer that arises from mesenchymal tissue of the uterus and has a benign glandular component.

Mucinous tumors are part of the surface epithelial-stromal tumor group of ovarian neoplasms, and account for approximately 36% of all ovarian tumors.

Approximately 75% are benign, 10% are borderline and 15% are malignant.

Rarely, the tumor is seen bilaterally; approximately 5% of primary mucinous tumors are bilateral.

"Benign" mucinous tumors are typically multilocular (have several lobes), and the cysts have a smooth lining of epithelium that resembles endocervical epithelial cells with small numbers of gastrointestinal-type epithelial cells.

"Borderline" and "malignant" mucinous tumors often have papillae and solid areas.

There may also be hemorrhage and necrosis.

It is well documented that malignancy may be only focally present in mucinous neoplasms of the ovary, so thorough sampling is imperative.

The major distinguishing features of mucinous tumors are that the tumors are filled with a mucus-like material, which gives them their name; this mucus is produced by mucus-secreting goblet cells very similar to the cells lining normal intestine.

These tumors may become very large, some have been weighed as large as 25 kilograms.

Cystadenocarcinomas (malignant tumors) contain a more solid growth pattern with the hallmarks of malignancy: cellular atypia and stratification, loss of the normal architecture of the tissue, and necrosis. The appearance can look similar to colonic cancer.

Clear stromal invasion is used to differentiate borderline tumors from malignant tumors.

Pseudomyxoma peritonei may present as a result of an ovarian mucinous tumor, however this is a rare cause of this condition, which is a rare condition. A more common cause of pseudomyxoma peritonei is a mucin-producing tumor of the appendix.

Since mucinous tumors arising from the ovary usually only involve one ovary, the presence of involvement in both ovaries with a mucinous tumor suggests that the tumor may have arisen in another location, and further study is warranted.

The risk of mucinous tumors is significantly associated with smoking: relative risk for current smokers 2.22 (2.22 times the risk for non-smokers) and 2.02 for past smokers. Risk is also associated with smoking duration: relative risk per 20 years was 1.44. See article by Tworoger SS in Cancer March 1, 2008 using data from the Nurses Health Study.

"Benign" serous tumours are unilocular (have one lobe); however if very large may be multilocular, contain clear fluid and have a smooth lining composed of columnar epithelial cells with cilia. On gross examination, the serous tumor may present as either a cystic lesion in which the papillary epithelium is contained within a few fibrous walled cysts, or the papillary projections may be away from the surface epithelium. Surgery is curative.

A mixed tumor is a tumor derived from one cell type that has divergent differentiation.

Examples include pleomorphic adenoma and Mixed Müllerian tumor.

Although the precise causes are not known, a link with certain variants of BRCA1/2 has been described. Furthermore, women with BRCA1/2 mutation have a 5% risk of developing primary peritoneal cancer even after prophylactic oophorectomy.

Primary peritoneal carcinoma shows similar rates of tumor suppressor gene dysfunction (p53, BRCA, WT1) as ovarian cancer and can also show an increased expression of HER-2/neu.

An association with vascular endothelial growth factor has been observed.

Dysgerminoma is the most common type of malignant germ cell ovarian cancer. Dysgerminoma usually occurs in adolescence and early adult life; about 5% occur in pre-pubertal children. Dysgerminoma is extremely rare after age 50. Dysgerminoma occurs in both ovaries in 10% of patients and, in a further 10%, there is microscopic tumor in the other ovary.

Seminoma is the second most common testicular cancer; the most common is mixed, which may contain seminoma.

Abnormal gonads (due to gonadal dysgenesis and androgen insensitivity syndrome) have a high risk of developing a dysgerminoma. Most dysgerminomas are associated with elevated serum lactic dehydrogenase (LDH), which is sometimes used as a tumor marker.

Metastases are most often present in the lymph nodes.