Case discussion
01Clinical context
An adnexal cystic lesion identified on prior imaging was referred for dedicated MRI characterisation.
02Key imaging findings
MRI demonstrates a 7.0 × 5.4 cm predominantly cystic right ovarian mass containing an enhancing mural solid/nodular component up to approximately 2.0 cm in thickness. The solid tissue shows heterogeneous post-contrast enhancement with areas of diffusion restriction. A rim of residual normal ovarian parenchyma along the anterior margin confirms ovarian origin. No macroscopic or chemical-shift fat, no visceral invasion, no lymphadenopathy, ascites or peritoneal disease.
03Diagnostic reasoning
Characterisation rested on the multiparametric protocol. Post-contrast sequences identified an enhancing mural solid/nodular component up to 2.0 cm, and diffusion-weighted imaging with ADC showed restricted diffusion within that tissue, establishing it as genuine enhancing solid tissue rather than debris or clot. Chemical-shift/fat-sensitive sequences showed no macroscopic fat, arguing against a teratomatous component. A residual rim of normal ovarian parenchyma along the anterior margin confirmed ovarian origin. The remainder of the pelvis was surveyed for visceral invasion, nodes, ascites and peritoneal disease, all of which were absent. The report assigned O-RADS MRI 4 on the available morphologic and enhancement information; it did not state which enhancement criterion applied, and none is inferred here.
04Questions for clinical practice
Does O-RADS MRI 4 mean cancer? No. It denotes intermediate risk of malignancy; it is a risk category, not a histological diagnosis. Tissue assessment at surgery provides the definitive answer. What happens next? The report recommends referral to a gynaecologist or gynaecologic oncologist for further management and surgical assessment, with correlation to serum tumour markers to assist preoperative risk stratification. Did the MRI show spread? No — there was no evidence of local visceral invasion, pelvic lymphadenopathy, ascites or peritoneal disease within the imaged field.
05Teaching point
The report assigned O-RADS MRI 4 — intermediate risk of malignancy — and recommended referral to a gynaecologist or gynaecologic oncologist for further management and surgical assessment. O-RADS MRI risk assessment rests on the applicable assessment pathway; the report did not state which criterion applied, so this case records the category as assigned rather than explaining what earns it. The category expresses imaging risk, not a histological diagnosis.
Shown for education. De-identified — no identifiable patient data. A radiology report is a specialist opinion and must be read with the full clinical context by the treating physician.