There is no simple and reliable way to test for ovarian cancer in women who do not have any signs or symptoms. The Pap test does not screen for ovarian cancer.

Screening is not recommended in women who are at average risk, as evidence does not support a reduction in death and the high rate of false positive tests may lead to unneeded surgery, which is accompanied by its own risks.

Ovarian cancer is usually only palpable in advanced stages. Screening is not recommended using CA-125 measurements, HE4 levels, ultrasound, or adnexal palpation in women who are at average risk. Risk of developing ovarian cancer in those with genetic factors can be reduced. Those with a genetic predisposition may benefit from screening. This high risk group has benefited with earlier detection.

Ovarian cancer has low prevalence, even in the high-risk group of women from the ages of 50 to 60 (about one in 2000), and screening of women with average risk is more likely to give ambiguous results than detect a problem which requires treatment. Because ambiguous results are more likely than detection of a treatable problem, and because the usual response to ambiguous results is invasive interventions, in women of average risk, the potential harms of having screening without an indication outweigh the potential benefits. The purpose of screening is to diagnose ovarian cancer at an early stage, when it is more likely to be treated successfully.

Screening with transvaginal ultrasound, pelvic examination, and CA-125 levels can be used instead of preventative surgery in women who have BRCA1 or BRCA2 mutations. This strategy has shown some success.

A prospective study of ovarian sex cord–stromal tumours in children and adolescents began enrolling participants in 2005.

A retrospective study of 83 women with sex cord–stromal tumours (73 with granulosa cell tumour and 10 with Sertoli-Leydig cell tumour), all diagnosed between 1975 and 2003, reported that survival was higher with age under 50, smaller tumour size, and absence of residual disease. The study found no effect of chemotherapy. A retrospective study of 67 children and adolescents reported some benefit of cisplatin-based chemotherapy.

Presence of an ovarian tumour plus hormonal disturbances suggests a Leydig cell tumour, granulosa cell tumour or thecoma. However, hormonal disturbances, in Leydig tumours, is present in only 2/3 of cases. Testicular Leydig cell tumours can be detected sonographically, ultrasound examinations may be ordered in the event of a palpable scrotal lump, however incidental identification of these lesions is also possible.

A conclusive diagnosis is made via histology, as part of a pathology report made during or after surgery. Reinke crystals are classically found in these tumours and help confirm the diagnosis, although they are seen in less than half of all Leydig cell tumours. See also Sex cord-stromal tumour. Immunohistochemical markers of Leydig cell tumours include inhibin-alpha, calretinin, and melan-A.

Routine screening of asymptomatic people is not indicated, since the disease is highly curable in its early, symptomatic stages. Instead, women, particularly menopausal women, should be aware of the symptoms and risk factors of endometrial cancer. A cervical screening test, such as a Pap smear, is not a useful diagnostic tool for endometrial cancer because the smear will be normal 50% of the time. A Pap smear can detect disease that has spread to the cervix. Results from a pelvic examination are frequently normal, especially in the early stages of disease. Changes in the size, shape or consistency of the uterus and/or its surrounding, supporting structures may exist when the disease is more advanced. Cervical stenosis, the narrowing of the cervical opening, is a sign of endometrial cancer when pus or blood is found collected in the uterus (pyometra or hematometra).

Women with Lynch syndrome should begin to have annual biopsy screening at the age of 35. Some women with Lynch syndrome elect to have a prophylactic hysterectomy and salpingo-oophorectomy to greatly reduce the risk of endometrial and ovarian cancer.

Transvaginal ultrasound to examine the endometrial thickness in women with postmenopausal bleeding is increasingly being used to aid in the diagnosis of endometrial cancer in the United States. In the United Kingdom, both an endometrial biopsy and a transvaginal ultrasound used in conjunction are the standard of care for diagnosing endometrial cancer. The homogeneity of the tissue visible on transvaginal ultrasound can help to indicate whether the thickness is cancerous. Ultrasound findings alone are not conclusive in cases of endometrial cancer, so another screening method (for example endometrial biopsy) must be used in conjunction. Other imaging studies are of limited use. CT scans are used for preoperative imaging of tumors that appear advanced on physical exam or have a high-risk subtype (at high risk of metastasis). They can also be used to investigate extrapelvic disease. An MRI can be of some use in determining if the cancer has spread to the cervix or if it is an endocervical adenocarcinoma. MRI is also useful for examining the nearby lymph nodes.

Dilation and curettage or an endometrial biopsy are used to obtain a tissue sample for histological examination. Endometrial biopsy is the less invasive option, but it may not give conclusive results every time. Hysteroscopy only shows the gross anatomy of the endometrium, which is often not indicative of cancer, and is therefore not used, unless in conjunction with a biopsy. Hysteroscopy can be used to confirm a diagnosis of cancer. New evidence shows that D&C has a higher false negative rate than endometrial biopsy.

Before treatment is begun, several other investigations are recommended. These include a chest x-ray, liver function tests, kidney function tests, and a test for levels of CA-125, a tumor marker that can be elevated in endometrial cancer.

Diagnosis of ovarian cancer starts with a physical examination (including a pelvic examination), a blood test (for CA-125 and sometimes other markers), and transvaginal ultrasound. Sometimes a rectovaginal examination is used to help plan a surgery. The diagnosis must be confirmed with surgery to inspect the abdominal cavity, take biopsies (tissue samples for microscopic analysis), and look for cancer cells in the abdominal fluid. This helps to determine if an ovarian mass is benign or malignant.

Ovarian cancer's early stages (I/II) are difficult to diagnose because most symptoms are nonspecific and thus of little use in diagnosis; as a result, it is rarely diagnosed until it spreads and advances to later stages (III/IV). Additionally, symptoms of ovarian cancer may appear similar to irritable bowel syndrome. In patients in whom pregnancy is a possibility, BHCG level can be measured during the diagnosis process. Serum alpha-fetoprotein, neuron-specific enolase, and lactate dehydrogenase can be measured in young girls and adolescents with suspected ovarian tumors as younger patients are more likely to have malignant germ cell tumors.

A physical examination, including a pelvic examination, and a pelvic ultrasound (transvaginal or otherwise) are both essential for diagnosis: physical examination may reveal increased abdominal girth and/or ascites (fluid within the abdominal cavity), while pelvic examination may reveal an ovarian or abdominal mass. An adnexal mass is a significant finding that often indicates ovarian cancer, especially if it is fixed, nodular, irregular, solid, and/or bilateral. 13–21% of adnexal masses are caused by malignancy; however, there are other benign causes of adnexal masses, including ovarian follicular cyst, leiomyoma, endometriosis, ectopic pregnancy, hydrosalpinx, tuboovarian abscess, ovarian torsion, dermoid cyst, cystadenoma (serous or mucinous), diverticular or appendiceal abscess, nerve sheath tumor, pelvic kidney, ureteral or bladder diverticulum, benign cystic mesothelioma of the peritoneum, peritoneal tuberculosis, or paraovarian cyst. Ovaries that can be felt are also a sign of ovarian cancer in postmenopausal women. Other parts of a physical examination for suspected ovarian cancer can include a breast examination and a digital rectal exam. Palpation of the supraclavicular, axillary, and inguinal lymph nodes may reveal lymphadenopathy, which can be indicative of metastasis. Another indicator may be the presence of a pleural effusion, which can be noted on auscultation.

When an ovarian malignancy is included in a list of diagnostic possibilities, a limited number of laboratory tests are indicated. A complete blood count and serum electrolyte test is usually obtained; when an ovarian cancer is present, these tests often show a high number of platelets (20–25% of people) and low blood sodium levels due to chemical signals secreted by the tumor. A positive test for inhibin A and inhibin B can indicate a granulosa cell tumor.

A blood test for a marker molecule called CA-125 is useful in differential diagnosis and in follow up of the disease, but it by itself has not been shown to be an effective method to screen for early-stage ovarian cancer due to its unacceptable low sensitivity and specificity. CA-125 levels in premenopausal people over 200 U/mL may indicate ovarian cancer, as may any elevation in CA-125 above 35 U/mL in post-menopausal people. CA-125 levels are not accurate in early stage ovarian cancer, as fully half of stage I ovarian cancer patients have a normal CA-125 level. CA-125 may also be elevated in benign (non-cancerous) conditions, including endometriosis, pregnancy, uterine fibroids, menstruation, ovarian cysts, systemic lupus erythematosus, liver disease, inflammatory bowel disease, pelvic inflammatory disease, and leiomyoma. HE4 is another candidate for ovarian cancer testing, though it has not been extensively tested. Other tumor markers for ovarian cancer include CA19-9, CA72-4, CA15-3, immunosuppressive acidic protein, haptoglobin-alpha, OVX1, mesothelin, lysophosphatidic acid, osteopontin, and fibroblast growth factor 23.

Use of blood test panels may help in diagnosis. The OVA1 panel includes CA-125, beta-2 microglobulin, transferrin, apolipoprotein A1, and transthyretin. OVA1 above 5.0 in premenopausal people and 4.4 in postmenopausal people indicates a high risk for cancer. A different set of laboratory tests is used for detecting sex cord-stromal tumors. High levels of testosterone or dehydroepiandrosterone sulfate, combined with other symptoms and high levels of inhibin A and inhibin B can be indicative of an SCST of any type.

Current research is looking at ways to consider tumor marker proteomics in combination with other indicators of disease (i.e. radiology and/or symptoms) to improve diagnostic accuracy. The challenge in such an approach is that the disparate prevalence of ovarian cancer means that even testing with very high sensitivity and specificity will still lead to a number of false positive results, which in turn may lead to issues such as performing surgical procedures in which cancer is not found intraoperatively. Genomics approaches have not yet been developed for ovarian cancer.

CT scanning is preferred to assess the extent of the tumor in the abdominopelvic cavity, though magnetic resonance imaging can also be used. CT scanning can also be useful for finding omental caking or differentiating fluid from solid tumor in the abdomen, especially in low malignant potential tumors. However, it may not detect smaller tumors. Sometimes, a chest x-ray is used to detect metastases in the chest or pleural effusion. Another test for metastatic disease, though it is infrequently used, is a barium enema, which can show if the rectosigmoid colon is involved in the disease. Positron emission tomography, bone scans, and paracentesis are of limited use; in fact, paracentesis can cause metastases to form at the needle insertion site and may not provide useful results. However, paracentesis can be used in cases where there is no pelvic mass and ascites is still present. A physician suspecting ovarian cancer may also perform mammography or an endometrial biopsy (in the case of abnormal bleeding) to assess the possibility of breast malignancies and endometrial malignancy, respectively. Vaginal ultrasonography is often the first-line imaging study performed when an adnexal mass is found. Several characteristics of an adnexal mass indicate ovarian malignancy; they usually are solid, irregular, multilocular, and/or large; and they typically have papillary features, central vessels, and/or irregular internal septations. However, SCST has no definitive characteristics on radiographic study.

To definitively diagnose ovarian cancer, a surgical procedure to inspect the abdomen is required. This can be an open procedure (laparotomy, incision through the abdominal wall) or keyhole surgery (laparoscopy). During this procedure, suspicious tissue is removed and sent for microscopic analysis. Usually, this includes a unilateral salpingo-oophorectomy, removal of a single affected ovary and Fallopian tube. Fluid from the abdominal cavity can also be analyzed for cancerous cells. If cancer is found, this procedure can also be used to determine the extent of its spread (which is a form of tumor staging).

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

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

Presence of an ovarian tumour plus hormonal disturbances suggests a Sertoli–Leydig cell tumour. However, hormonal disturbance is present in only 2/3 of cases. A conclusive diagnosis is made via histology, as part of a pathology report made during or after surgery. See also Sex cord-stromal tumour.

Diagnosis of endometrial cancer is made first by a physical examination and dilation and curettage (removal of endometrial tissue; D&C). This tissue is then examined histologically for characteristics of cancer. If cancer is found, medical imaging may be done to see whether the cancer has spread or invaded tissue.

Blood tests may detect the presence of placental alkaline phosphatase (PLAP) in fifty percent of cases. However, PLAP cannot usefully stand alone as a marker for seminoma and contributes little to follow-up, due to its rise with smoking. Human chorionic gonadotropin (hCG) may be elevated in some cases, but this correlates more to the presence of trophoblast cells within the tumour than to the stage of the tumour. A classical or pure seminoma by definition do not cause an elevated serum alpha fetoprotein . Lactate dehydrogenase (LDH) may be the only marker that is elevated in some seminomas. The degree of elevation in the serum LDH has prognostic value in advanced seminoma.

The cut surface of the tumour is fleshy and lobulated, and varies in colour from cream to tan to pink. The tumour tends to bulge from the cut surface, and small areas of hemorrhage may be seen. These areas of hemorrhage usually correspond to trophoblastic cell clusters within the tumour.

Microscopic examination shows that seminomas are usually composed of either a sheet-like or lobular pattern of cells with a fibrous stromal network. The fibrous septa almost always contain focal lymphocyte inclusions, and granulomas are sometimes seen. The tumour cells themselves typically have abundant clear to pale pink cytoplasm containing abundant glycogen, which is demonstrable with a periodic acid-Schiff (PAS) stain. The nuclei are prominent and usually contain one or two large nucleoli, and have prominent nuclear membranes. Foci of syncytiotrophoblastic cells may be present in varied amounts. The adjacent testicular tissue commonly shows intratubular germ cell neoplasia, and may also show variable spermatocytic maturation arrest.

POU2AF1 and PROM1 have been proposed as possible markers.

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%.

After removal, the testicle is fixed with Bouin's solution because it better conserves some morphological details such as nuclear conformation. Then the testicular tumor is staged by a pathologist according to the TNM Classification of Malignant Tumors as published in the AJCC Cancer Staging Manual. Testicular cancer is categorized as being in one of three stages (which have subclassifications). The size of the tumor in the testis is irrelevant to staging. In broad terms, testicular cancer is staged as follows:

- Stage I: the cancer remains localized to the testis.

- Stage II: the cancer involves the testis and metastasis to retroperitoneal and/or paraaortic lymph nodes (lymph nodes below the diaphragm).

- Stage III: the cancer involves the testis and metastasis beyond the retroperitoneal and paraaortic lymph nodes. Stage 3 is further subdivided into non-bulky stage 3 and bulky stage 3.

Further information on the detailed staging system is available on the website of the American Cancer Society.

The usual chemotherapy regimen has limited efficacy in tumours of this type, although Imatinib has shown some promise. There is no current role for radiotherapy.

The usual treatment is surgery. The surgery for females 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 Leydig cell tumour does not produce elevated tumour markers, the focus of surveillance is on repeated physical examination and imaging.

In males, a radical inguinal orchiectomy is typically performed. However, testes-sparing surgery can be used to maintain fertility in children and young adults. This approach involves an inguinal or scrotal incision and ultrasound guidance if the tumour is non-palpable. This can be done because the tumour is typically unifocal, not associated with precancerous lesions, and is unlikely to recur.

The prognosis is generally good as the tumour tends to grow slowly and usually is benign: 10% 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 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.

Intratesticular masses that appear suspicious on an ultrasound should be treated with an inguinal orchiectomy. The pathology of the removed testicle and spermatic cord indicate the presence of the seminoma and assist in the staging. Tumors with both seminoma and nonseminoma elements or that occur with the presence of AFP should be treated as nonseminomas. Abdominal CT or MRI scans as well as chest imaging are done to detect for metastasis. The analysis of tumor markers also helps in staging.

The preferred treatment for most forms of stage 1 seminoma is active surveillance. Stage 1 seminoma is characterized by the absence of clinical evidence of metastasis. Active surveillance consists of periodic history and physical examinations, tumor marker analysis, and radiographic imaging. Around 85-95% of these cases will require no further treatment. Modern radiotherapy techniques as well as one or two cycles of single-agent carboplatin have been shown to reduce the risk of relapse, but carry the potential of causing delayed side effects. Regardless of treatment strategy, stage 1 seminoma has nearly a 100% cure rate.

Stage 2 seminoma is indicated by the presence of retroperitoneal metastasis. Cases require radiotherapy or, in advanced cases, combination chemotherapy. Large residual masses found after chemotherapy may require surgical resection. Second-line treatment is the same as for nonseminomas.

Stage 3 seminoma is characterized by the presence of metastasis outside the retroperitoneum—the lungs in "good risk" cases or elsewhere in "intermediate risk" cases. This is treated with combination chemotherapy. Second-line treatment follows nonseminoma protocols.

The main way testicular cancer is diagnosed is via a lump or mass inside a testis. More generally, if a young adult or adolescent has a single enlarged testicle, which may or may not be painful, this should give doctors reason to suspect testicular cancer.

Other conditions may also have symptoms similar to testicular cancer:

- Epididymitis or epididymoorchitis

- Hematocele

- Varicocele

- Orchitis

- Prostate infections or inflammations (prostatitis), bladder infections or inflammations (cystitis), or kidney (renal) infections (nephritis) or inflammations which have spread to and caused swelling in the vessels of the testicles or scrotum

- Testicular torsion or a hernia

- Infection, inflammation, retro-peritonitis, or other conditions of the lymph nodes or vessels near the scrotum, testicles, pubis, anorectal area, and groin

- Benign tumors or lesions of the testicles

- Metastasis to the testicles from another, primary tumor site(s)

The nature of any palpated lump in the scrotum is often evaluated by scrotal ultrasound, which can determine exact location, size, and some characteristics of the lump, such as cystic vs solid, uniform vs heterogeneous, sharply circumscribed or poorly defined. The extent of the disease is evaluated by CT scans, which are used to locate metastases.

The differential diagnosis of testicular cancer requires examining the histology of tissue obtained from an inguinal orchiectomy - that is, surgical excision of the entire testis along with attached structures (epididymis and spermatic cord). A biopsy should not be performed, as it raises the risk of spreading cancer cells into the scrotum.

Inguinal orchiectomy is the preferred method because it lowers the risk of cancer cells escaping. This is because the lymphatic system of the scrotum, through which white blood cells (and, potentially, cancer cells) flow in and out, links to the lower extremities, while that of the testicle links to the back of the abdominal cavity (the retroperitoneum). A transscrotal biopsy or orchiectomy will potentially leave cancer cells in the scrotum and create two routes for cancer cells to spread, while in an inguinal orchiectomy only the retroperitoneal route exists.

Blood tests are also used to identify and measure tumor markers (usually proteins present in the bloodstream) that are specific to testicular cancer. Alpha-fetoprotein, human chorionic gonadotropin (the "pregnancy hormone"), and LDH-1 are the typical tumor markers used to spot testicular germ cell tumors.

A pregnancy test may be used to detect high levels of chorionic gonadotropin; however, the first sign of testicular cancer is usually a painless lump. Note that only about 25% of seminomas have elevated chorionic gonadotropin, so a pregnancy test is not very sensitive for making out testicular cancer.

A pelvic examination may detect an adnexal mass. A CA-125 blood test is a nonspecific test that tends to be elevated in patients with tubal cancer. More specific tests are a gynecologic ultrasound examination, a CT scan, or an MRI of the pelvis.

Occasionally, an early fallopian tube cancer may be detected serendipitously during pelvic surgery.

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%

Inhibin, a hormone, has been used as tumor marker for granulosa cell tumor.

Dysgerminomas, like other seminomatous germ cell tumors, are very sensitive to both chemotherapy and radiotherapy. For this reason, with treatment patients' chances of long-term survival, even cure, is excellent.

Gonadoblastomas can contain elements of both germ cells and gonadal stroma.

Formerly, gonadoblastoma was sometimes regarded as a subset of dysgerminoma. In modern literature, it is sometimes considered to progress to dysgerminoma.

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.

Prognosis depends to a large degree on the stage of the condition. In 1991 it was reported that about half of the patients with advanced stage disease survived 5 years with a surgical approach followed by cisplatinum-based chemotherapy.