Diagnostic Ultrasound - Abdomen and Pelvis

Serous Ovarian Cystadenoma/Carcinoma
Diagnoses: Female Pelvis
TERMINOLOGY
• Serous epithelial neoplasm, which can be benign (serous
cystadenoma), borderline (low malignant potential) or
malignant (serous cystadenocarcinoma)
IMAGING
• Large, thin-walled, unilocular mass ± papillary projections
• Bilateral in 25% of benign tumors and 65% of malignant
tumors
• Variable size but often large
• Typically unilocular or with few septations even in
malignant tumors
• May see ascites and peritoneal implants in metastatic
disease
• Ultrasound ideal method for lesion detection and
characterization
• CT preferred for tumor staging
○ Evaluate along paracolic gutters and capsule of liver for
peritoneal disease
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• Mucinous cystadenoma/carcinoma
PATHOLOGY
• Metastatic spread
○ Intraperitoneal dissemination most common
○ Direct extension into surrounding organs
○ Lymphatic spread to paraaortic and pelvic nodes
CLINICAL ISSUES
• Pelvic discomfort/pain from large tumors
• 70% of patients with malignant tumors have peritoneal
involvement at time of diagnosis
• Serous tumors most common epithelial neoplasm
• Malignant 25%, borderline 15%, benign 60%
DIAGNOSTIC CHECKLIST
• Serous cystadenoma is most likely diagnosis for large,
anechoic, unilocular cyst in postmenopausal woman
(Left) Typical serous epithelial
neoplasms are large with thin
walls and unilocular. This
ovarian serous cystadenoma
measured up to 18 cm in
diameter on this
transabdominal grayscale
ultrasound. (Right) Gross
pathology after the fluid has
been drained shows the thin
wall typical of a serous
cystadenoma. They are
typically unilocular or have
few septations.
(Left) Close evaluation of this
serous cystadenoma reveals
subtle nodularity along the
right lateral margin of the
wall st. (Right) Axial CECT of
the same patient shows subtle
enhancing nodules st at the
site of the sonographic
finding, which correlated with
areas of focal borderline
neoplasm.
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