Ovarian serous tumors

Ovarian serous neoplasms are the commonest of four general types of the epithelial ovarian tumors, and are more prevalent than the mucinous ovarian tumors.

Serous ovarian neoplasms are subdivided into benign, borderline, and malignant lesions according to their malignant potential and clinical behavior (see Pathology - Classification section below).

Epidemiology

Approximately 60% are benign and ~15% of borderline malignancy; These occur most commonly in women of reproductive age. The malignant tumors comprise of 25% of cases and tend to occur in older patients.

Pathology

Serous ovarian tumors are defined by a histologic resemblance to normal Fallopian tubal epithelium .

Classification

The most recent 2014 WHO classification system for serous ovarian neoplasia identifies three categories of tumor:

• benign - no cellular proliferation or invasion
  • serous cystadenoma
  • serous cystadenofibroma
  • serous surface papilloma
• borderline - cellular proliferation + minor nuclear atypia without invasion
  • borderline serous cystadenoma
• malignant - cellular proliferation + nuclear atypia + stromal invasion
  • low grade serous carcinoma
  • high grade serous carcinoma - most common serous carcinoma (85-90% serous carcinomas), highest associated mortality

Radiographic features

Imaging evaluation may be performed preferably with ultrasound or MRI, with CT usually reserved for staging purposes. In general, the cell type (e.g. serous, mucinous) often cannot be determined on the imaging basis of appearances.

Serous ovarian tumors are typically smaller than mucinous tumors on presentation. They are typically unilocular and homogeneous. They are often bilateral, and this is particularly so for the malignant subtypes. Psammomatous calcification is a feature of serous, but not mucinous subtypes.

Features that suggest a malignant over a benign cystic neoplasm include:

• large cystic mass
• thick irregular walls and septa
• papillary projections
• large soft tissue component
• ascites
• evidence of invasive spread or adenopathy

Differential diagnosis

Considerations include:

• ovarian functional cyst
  • usually smaller
  • thin walls with no septations 
  • tend to change or resolve in the next menstrual cycle
• para ovarian cyst
  • ovaries can be individualized apart from the cyst 
• ovarian mucinous tumors
  • tend to be multiseptated 
  • often larger than serous tumors
  • monolateral rather than bilateral
  • cystic loculi with variable signal intensities on MRI giving the appearances of "stained glass"

See also

• ovarian tumor
• ovarian cancer staging

• benign serous cystadenoma / serous cystadenofibroma
• borderline cystadenoma
• malignant serous cystadenocarcinoma

Siehe auch:

• seröses Boderline-Zystadenom des Ovars
• seröses Zystadenom des Ovars
• Serous inclusion cysts of the ovary
• seröses Zystadenokarzinom des Ovars
• seromuzinöses Zystadenom des Ovars