Page 528 - Concise Pathology for Exam Preparation ( PDFDrive )

18 Female Genital System 513

• Five to ten percent of ovarian carcinomas are familial and may be caused by mutations
in BRCA1 and BRCA2 genes (mutations in these genes may increase risk for both
ovarian and breast carcinoma).
• The protein HER2/neu is overexpressed in 35% of ovarian cancers and its over-expression
is associated with a poor prognosis.
• KRAS is expressed in 30% of tumours (mostly mucinous cystadenocarcinomas).
• p53 is mutated in about 50% of all ovarian cancers.
Low-grade serous adenocarcinomas show KRAS, BRAF or ERBB2 mutations. High-
grade tumours show TP53 mutations and lack KRAS or BRAF mutations.

Clinical Features of Ovarian Tumours

• Generally produce no signs or symptoms till they are advanced.
• Clinical presentation is similar despite morphological diversity.
• Functional tumours produce hormones causing endocrinopathies.
• Benign tumours generally produce pressure symptoms due to their size (pain, urinary
frequency and gastrointestinal symptoms) and malignant tumours may present with
weakness, weight loss and cachexia.
• Torsion of tumours on their pedicles may present as an acute emergency.
• Fibromas and malignant tumours may produce ascites.

Screening Modalities for Ovarian Tumours
• Radiology
• Elevation of markers like glycoprotein CA-125 and osteopontin is noted in 75–90% of
women with epithelial ovarian cancers (CA-125 may also be increased, however, in
benign conditions as well as nonovarian cancers and may be undetectable in a large
number of women with ovarian cancer with no extra ovarian spread).

Salient Features of Different Ovarian Tumours
1. Epithelial ovarian tumours (surface epithelial tumours)
Behaviour of surface epithelial tumours depends on their pathological features:
• Benign tumours show simple, nonstratified epithelium, with no cytological atypia.
• Atypical proliferative tumours (borderline tumours) show epithelial proliferation
with stratification and tufting, variable mitotic activity and nuclear atypia, but no
stromal invasion.
• Malignant tumours (carcinomas) show stromal invasion and marked cytological atypia.
Types:
• Serous: Lining resembles fallopian tube epithelium.
• Mucinous: Lining resembles gastrointestinal tract or endocervical epithelium.
• Endometrioid: Lining resembles proliferative endometrium.
• Clear cell: Lining resembles gestational endometrium.
• Transitional cell (Brenner): Lining resembles urinary tract epithelium.
(a) Serous tumours
• Most frequent ovarian tumours.
• Sixty percent are benign tumours, 15% of low malignant potential and 25%
malignant.
• Twenty percent of the benign and 60% of the malignant tumours are bilateral.
• Average size is smaller than mucinous tumours.
• Lining may be smooth or papillary (cauliflower-like masses composed of soft
brittle tissue may be seen in malignant tumours). Cysts are filled with clear fluid
and lined by cuboidal epithelium with apical mucin.
• Changes suggestive of malignancy are
- Predominance of papillary projections and solid areas
- Presence of haemorrhage and necrosis
- Invasion of cyst wall
- Irregular nodular surface due to penetration of the serosal covering by the tumour.

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