Dysgerminoma is the most common malignant ovarian germ cell tumor, accounting for 1-2% of all ovarian malignancies. It is histologically equivalent to testicular seminoma. Occurs in young women (<30 years, peak 15-25) and is the most common ovarian malignancy in women under 30. Typically presents as a solid, homogeneous, lobulated mass. Bilateral involvement occurs in 10-15%. LDH is markedly elevated and serves as a diagnostic/follow-up marker. Highly sensitive to chemotherapy and radiotherapy — cure rate exceeds 90% even in advanced stages.
Age Range
10-30
Peak Age
20
Gender
Female predominant
Prevalence
Rare
Dysgerminoma originates from primordial germ cells. These are totipotent cells that migrate to the gonads during embryonic development. The tumor consists of uniform large round cells (clear cytoplasm rich in glycogen) and lymphocytic infiltration within fibrous septa. The solid homogeneous structure of the tumor is explained by uniform cellular composition — cystic/necrotic degeneration is rare and may be seen in large tumors. Fibrovascular septa create a lobulated appearance and are seen as contrast-retaining bands on imaging. The tumor's rich vascular structure leads to intense and uniform enhancement. Strong association with gonadal dysgenesis (46,XY DSD — Swyer syndrome, Turner mosaicism) — risk is increased 10-30 fold in these patients. Shows intermediate-high T2 signal because cells are glycogen-rich and free water content is higher than fibrous tumors. Shows diffusion restriction on DWI due to dense cellular structure.
Lobulated appearance created by fibrous septa in a solid, homogeneous, intensely enhancing ovarian mass in a young woman. These septa appear as low-density/signal bands on contrast CT/MRI, dividing the mass into lobules. This is the ovarian equivalent of the 'septated solid mass' appearance of testicular seminoma. This finding strongly suggests germ cell tumor (dysgerminoma) in the differential diagnosis of a solid ovarian mass in a young woman.
Contrast-enhanced CT shows a solid, lobulated, intensely and homogeneously enhancing ovarian mass. Fibrous septa appear as low-density bands within the mass. Cystic/necrotic degeneration is rare in small tumors, may be seen in large (>10 cm) tumors. Mass is usually well-defined and unilateral. Retroperitoneal/para-aortic lymphadenopathy may accompany.
Report Sentence
A solid, lobulated, intensely and homogeneously enhancing mass is identified in the ovarian location with low-density bands consistent with fibrous septa; dysgerminoma should be the primary consideration in a young patient.
T2-weighted MRI shows the solid mass with intermediate-high signal intensity. Fibrous septa appear as T2-hypointense bands creating a lobulated appearance. T2 signal may be variable if necrosis or hemorrhage areas are present, but the mass is generally homogeneous. T2 signal intensity is distinctly higher than muscle, lower than fluid.
Report Sentence
The solid mass shows intermediate-high signal intensity on T2-weighted sequences with a lobulated appearance created by T2-hypointense septa, consistent with germ cell tumor (dysgerminoma).
Marked diffusion restriction is seen on DWI — bright signal on high b-values and low signal on ADC map. ADC values are generally <0.8 x 10-3 mm2/s. Diffusion restriction is homogeneous throughout the mass (except fibrous septa). This marked and homogeneous diffusion restriction reflects dysgerminoma's high cellularity.
Report Sentence
Marked and homogeneous diffusion restriction is observed in the solid mass on DWI with low ADC values, consistent with high cellularity and favoring germ cell tumor.
Contrast-enhanced MRI shows intense and homogeneous enhancement of the solid mass. Fibrous septa enhance relatively less and become more conspicuous as bands within the mass with contrast retention. This intense, uniform enhancement reflects dysgerminoma's rich vascular network and is more intense than most other solid ovarian tumors.
Report Sentence
Intense and homogeneous enhancement is observed in the solid mass on contrast-enhanced MRI with fibrous septa becoming conspicuous as low-signal bands; enhancement pattern consistent with dysgerminoma.
US shows a solid, homogeneous, intermediate echogenicity lobulated mass. Fibrous septa appear as hypoechoic bands within the mass. Cystic component is usually absent or minimal. Mass is well-defined and displaces surrounding structures (not invasive-appearing). Bilateral involvement is seen at 10-15% rate and the other ovary should be evaluated.
Report Sentence
A solid, homogeneous, lobulated mass is identified in the ovarian location on US without cystic component; germ cell tumor (dysgerminoma) should be primarily considered in the differential diagnosis of a young patient.
Doppler US shows markedly increased vascular flows within the mass — both central and peripheral vascular pattern. Prominent vascular flows are seen along fibrous septa. Low-resistance arterial flows indicate malignancy. This rich vascular architecture is the US equivalent of dysgerminoma's intense enhancement.
Report Sentence
Doppler examination demonstrates markedly increased vascular flows and low-resistance arterial flow pattern in the solid mass, consistent with a highly vascular tumor.
Criteria
Pure tumor containing only dysgerminoma component. 65-70% of all dysgerminomas. AFP and hCG are normal (LDH elevated). Best prognosis subtype.
Distinct Features
Homogeneous solid mass on imaging, no significant cystic/necrotic component. Intense homogeneous enhancement. Excellent response to BEP chemotherapy and radiotherapy. Stage I survival >95%.
Criteria
Dysgerminoma combined with other germ cell tumor components (yolk sac, embryonal, teratoma, choriocarcinoma). 10-15% of all dysgerminomas.
Distinct Features
Heterogeneous appearance on imaging — solid, cystic, hemorrhagic, and calcified areas may coexist. AFP (yolk sac), hCG (choriocarcinoma) may be elevated. Treatment and prognosis are determined by the most aggressive component.
Criteria
Dysgerminoma developing in the setting of 46,XY DSD (Swyer syndrome), Turner mosaicism (45,X/46,XY), or other gonadal dysgenesis syndromes. Gonadoblastoma may be a precursor lesion.
Distinct Features
Develops in streak gonad setting. Gonadoblastoma component may accompany — calcifications on CT/MRI are a finding favoring gonadoblastoma. Bilateral risk is high. Prophylactic gonadectomy is recommended. Imaging features are similar to sporadic dysgerminoma but calcification may accompany.
Distinguishing Feature
GCT shows 'sponge/Swiss cheese' pattern (cystic foci within solid background) and T2-hypointense solid component. Dysgerminoma is entirely solid, intermediate-high T2 signal, and contains no cystic foci. GCT produces estrogen (endometrial thickening), dysgerminoma does not. GCT elevates inhibin B, dysgerminoma elevates LDH.
Distinguishing Feature
Ovarian fibroma is solid, markedly T2-hypointense (fibrous tissue), and shows minimal to no enhancement. Dysgerminoma shows intermediate-high T2 signal and intense enhancement. Fibroma may be associated with Meigs syndrome (ascites + pleural effusion). Fibroma is usually postmenopausal, dysgerminoma occurs in young women.
Distinguishing Feature
Ovarian metastasis (Krukenberg) appears as bilateral solid mass with primary tumor in another organ. Dysgerminoma occurs in young women and is a primary ovarian tumor. Signet-ring cells (if gastric origin) and primary tumor investigation differentiate. Age group is also important — metastasis usually in older age.
Urgency
urgentManagement
surgicalBiopsy
Not NeededFollow-up
3-monthTreatment is surgical — unilateral salpingo-oophorectomy + peritoneal staging (fertility preservation is priority in young patients). Highly sensitive to chemotherapy and radiotherapy — cure rate exceeds 90% with BEP chemotherapy even in advanced stages. Bilateral involvement is 10-15% so contralateral ovary must be carefully evaluated. Prophylactic gonadectomy is recommended in gonadal dysgenesis patients (46,XY DSD). Follow-up: LDH, physical exam, and imaging at 3-month intervals; after 2 years at 6-month intervals. Serum LDH re-elevates in recurrence. Urgent referral to gynecologic oncology is required when germ cell tumor is suspected in a young woman.
Dysgerminoma is highly chemosensitive (BEP regimen) with excellent prognosis (>95% 5-year survival). Fertility-sparing surgery (unilateral salpingo-oophorectomy) is possible in young patients. LDH and beta-hCG are follow-up markers.