Adnexal mass at initial imaging — structured oral station (12 minutes)

Opening prompt — "How would you characterise this mass?"

Model response — say it in this order: ^[1][2]

• "I would describe the mass in IOTA terminology — size in three dimensions, locularity, solid components, papillary projections, acoustic shadows, ascites and a colour Doppler score — and then apply the IOTA Simple Rules."
• "Five B features predict benignity, five M features predict malignancy. One or more M and no B means malignant; the reverse means benign; both or neither is inconclusive — and then I would use the ADNEX model or expert subjective assessment."
• "In the Timmerman prospective validation of 1938 masses, the Simple Rules were conclusive in 77% and gave a sensitivity of 92% and specificity of 96%. In IOTA phase 6 — the nationwide Italian validation of 1431 patients — every IOTA model outperformed the Risk of Malignancy Index, all clustering at AUC 0.91 to 0.92. The RMI is a tool of the past."^[1][9]

Probe 1 — "Would you send CA-125, AFP, hCG and inhibin?"

• "No — not routinely, in pregnancy. CA-125 is expressed by peritoneum, decidua and amniotic fluid and rises physiologically, peaking in the first trimester and at delivery. AFP, hCG and inhibin are produced by the pregnancy itself. Mid-range values are non-informative; I would interpret only an extreme value or a rising trend."
• "I would trust the imaging. If characterisation remained inconclusive, my second-line test would be non-contrast MRI — in Ray's JAMA cohort of over 1.4 million pregnancies, first-trimester MRI was not associated with fetal or childhood harm, but gadolinium at any gestation was associated with stillbirth, neonatal death and rheumatological or inflammatory skin outcomes. Gadolinium is out at any gestation."^[8]

Probe 2 — "She has endometriosis, and the mass has papillary projections with flow. Oncology referral?"

• "Not on these features alone — this is the classic decidualised endometrioma, the great mimic of this topic: progesterone-driven stromal change producing vascular papillary projections that imitate IOTA M features."
• "In the Barcroft two-step IOTA pilot in 291 pregnant women, decidualisation occurred in 31.1% of endometriomas and had resolved in 89.5% by the first postnatal scan. ADNEX misclassified 34% of benign masses as malignant — over half of them decidualised endometriomas."
• "Management is to resist surgery, obtain expert subjective assessment, follow with serial imaging, and rescan postnatally."^[4]

Probe 3 — "She re-presents at 13 weeks with sudden severe right iliac fossa pain and vomiting."

• "This is ovarian torsion until proven otherwise. IVF pregnancies carry a markedly higher risk — in Dvash's series, 47.9% of torsion cases in pregnancy followed IVF or ovulation induction, and three-quarters occurred in the first trimester."
• "The history makes the diagnosis; I would not delay theatre for definitive imaging. Analgesia, IV access, bloods, nil by mouth, anaesthetics and theatre, fetal heart documented."
• "At operation: laparoscopic detorsion with ovarian conservation — a dusky ovary usually recovers, and oophorectomy is reserved for confirmed necrosis. In Dvash's cohort, live birth was 92.5% and preterm delivery 19.4%."^[5]

Probe 4 — "If she needs elective surgery, when and how?"

• "Elective surgery belongs in the second trimester — after organogenesis and while access is still good. The counterweight: necessary surgery is never deferred for gestational age; a torsion at 32 weeks still goes to theatre."
• "Laparoscopy is preferred. In the Cagino meta-analysis, laparoscopy versus laparotomy showed no significant increase in spontaneous abortion (OR 1.53, 95% CI 0.67 to 3.52) or preterm delivery (OR 0.95, 95% CI 0.47 to 1.89), with a shorter stay — 2.5 versus 5.3 days. Elective surgery carried a lower preterm risk than emergency."
• "Technique: open or optical entry above the fundus, insufflation at 12 to 15 mmHg or less, capnography, left lateral tilt, minimal uterine manipulation, thromboprophylaxis, and the fetal heart documented before and after."^[6]

Probe 5 — "She asks: will surgery harm my baby?"

• "Surgery in pregnancy is generally safe — the attributable risk is low — but I would give her the absolute numbers from Balinskaite's cohort of 6.5 million pregnancies: one additional stillbirth per 287 operations, one additional preterm delivery per 31, one additional low-birthweight baby per 39, one additional caesarean per 25."
• "I would frame it honestly: the absolute risk to her pregnancy is small, and the operation is only offered for a good reason — torsion, symptoms, or a real concern about malignancy."^[7]

Probe 6 — "What if it had M features and ascites from the start?"

• "Then this stops being a watch-and-wait problem. I would refer to gynaecological oncology, stage with non-contrast MRI, and plan a multidisciplinary approach informed by ESGO/INCIP principles — in pregnancy exactly as outside it."
• "Only around 1% of adnexal masses that come to surgery in pregnancy are malignant, and borderline tumours dominate in this age group; the plan would usually be fertility-sparing where feasible, and iatrogenic prematurity is the avoidable harm."^[6]