GC118 Pelvic Mass Ovarian Cancer And Cysts; Uterine Fibroid; Pelvic Imaging
Pelvic masses encompass ovarian cysts and cancers as well as uterine fibroids, evaluated through imaging modalities such as ultrasound, CT, and MRI to determine their origin, characteristics, and malignant potential.
Pelvic Mass: Ovarian Cancer & Cysts, Uterine Fibroids, and Pelvic Imaging
This GC 118 lecture by Dr. Ka Yu Tse covers the systematic clinical approach to a pelvic mass — from history and examination through differential diagnosis, investigation (with emphasis on pelvic imaging), to management. The three pillars are:
- Uterine fibroids (leiomyomas) — the most common uterine neoplasm
- Ovarian cysts — benign adnexal masses and their complications
- Ovarian cancer — malignant ovarian tumours with staging, risk stratification tools (IOTA, RMI, ROMA, ADNEX), and management principles
Why this matters for exams: Pelvic mass is a favourite exam topic because it tests history-taking structure, systematic DDx generation, ultrasound interpretation, tumour marker knowledge (CA-125 pitfalls), and management decision-making based on age, menopausal status, and malignancy risk. Past papers have directly tested fibroid management (2018 SAQ Q11), ovarian mass ultrasound features (2022 SAQ Q12), and pelvic imaging modality choice (2025 MCQ Q1). [1][2][3][4]
How the lecture is structured:
- A. History taking → B. Physical examination → C. Differential diagnoses → D. Investigation & Pelvic imaging → E. Treatment
A. History Taking for Pelvic Mass
The lecture emphasises a structured gynaecological history: Age → Chief complaint details → Related symptoms → Menstrual history → Obstetric history → Sexual/contraception history → Family/drug/medical/surgical/allergy history. [1]
| Element | Why It Matters |
|---|---|
| Onset: how was the mass discovered | Incidental finding on imaging vs. patient-noticed lump changes your differential (incidental = more likely benign/asymptomatic fibroid) |
| Size and site | Suprapubic midline → uterine origin; lateral → adnexal; right iliac fossa → must also consider appendiceal/caecal pathology |
| Duration and change since first noted | Rapid growth raises concern for malignancy (especially sarcoma if uterine) or pregnancy |
| Associated symptoms: distension, pressure symptoms | Distension may be the mass itself OR ascites (critical distinction — ascites suggests malignancy) |
Menstrual pattern (regularity, amount), dysmenorrhoea, and associated symptoms (abdominal pain pattern, urinary/bowel symptoms, constitutional symptoms). [1]
- Compare with previous pattern — this is crucial. A woman who has always had heavy periods is different from one whose flow suddenly changed.
- Timing: Duration of flow, cycle length
- Amount of flow: Number of pads/tampons, clots, flooding, double protection
- Anaemic symptoms: Fatigue, dyspnoea on exertion, palpitations, dizziness
- DDx for heavy menstrual flow: fibroid, adenomyosis [1]
| Type | Features | DDx |
|---|---|---|
| Primary | Early onset (from menarche) | Structural abnormality should be considered |
| Secondary | No previous history of dysmenorrhoea; associated with menorrhagia, subfertility | Adenomyosis is the key DDx; also endometriosis, fibroids |
Why distinguish? Primary dysmenorrhoea starting from menarche is usually prostaglandin-mediated and functional. Secondary dysmenorrhoea developing later in life with new heavy bleeding or subfertility strongly points to structural pathology (adenomyosis, endometriosis, fibroids).
Due to pressure effect or invasion. DDx includes gynaecological diseases, non-gynaecological pathologies, and secondary ovarian cancer from bowel primary. [1]
Exam Trap
Don't forget that a pelvic mass causing bowel symptoms could be a primary bowel cancer (e.g., sigmoid/caecal carcinoma) or a secondary ovarian cancer from a bowel primary (Krukenberg tumour). The lecture explicitly flags this.
| Pathology | Symptoms (from lecture slides) |
|---|---|
| Fibroid | Asymptomatic; Menorrhagia; Abdominal distension; Pressure effect; Anaemia; Others — dysmenorrhoea can happen but not typical |
| Ovarian cyst | Asymptomatic; Abdominal distension (due to cyst or free fluid); Pressure symptoms (urinary/bowel); Abdominal pain due to mass effect or complications — sudden or chronic (torsion, haemorrhage, rupture); Dysmenorrhoea (endometriosis) |
| Ovarian cancer | Asymptomatic; Non-specific GI upset; Abdominal distension; Abdominal pain; Pressure symptoms; Complications (haemorrhage, rupture); Systemic symptoms (weight loss, appetite loss, unexplained fever, lower limb swelling, lymphadenopathy); Symptoms related to metastasis |
Key Discriminator
Fibroid = menorrhagia is the dominant symptom, pain is NOT typical (except red degeneration). Ovarian cyst = pain from complications (torsion/rupture/haemorrhage) is the distinguishing feature. Ovarian cancer = systemic/constitutional symptoms + non-specific GI upset are classic; distension may be from ascites rather than the mass itself.
B. Physical Examination
Manner: professionalism, privacy, chaperone. [1]
- Vital signs, pregnancy test, BMI, performance status — always exclude pregnancy first!
- Pallor (anaemia from menorrhagia or malignancy)
- Lymphadenopathy (metastatic disease — Virchow's node/left supraclavicular = Troisier's sign)
- Lower limb — oedema (DVT from pelvic mass compressing iliac veins, or malignancy-related)
- Systematic examination of cardiovascular, respiratory systems
Shape of abdomen; Mass (location, size, mobility, regular, consistency); Tenderness; Ascites. [1]
Key points from senior notes on abdominal mass assessment [5]:
- Can you get below it? If NO → likely liver/spleen/kidney. If YES → pelvic origin (bladder, uterus, ovary)
- Mobility: Uterine masses (fibroids) move with palpation but NOT with respiration. A mass that moves side-to-side is uterine. A mass that is fixed may be advanced malignancy or severe inflammation.
- Ascites: Shifting dullness. Ascites + pelvic mass = ovarian cancer until proven otherwise.
Lower genital tract → Uterus → Adnexal mass (size, tenderness, mobility, arising from pelvis) → Pouch of Douglas (nodularity, thickening, tenderness in endometriosis) → Rectal examination. [1]
| Pathology | Findings |
|---|---|
| Fibroid | Pallor?; Usually non-tender (except red degeneration); Symmetric/asymmetric/irregular; Firm mass arising from pelvis, rubbery consistency; Mass moved with the cervix. Special: pedunculated/subserosal fibroids, fibroid polyps |
| Ovarian cyst | Vital signs if in pain; Mobility, tenderness, peritoneal signs, consistency; Usually separated from uterus; Less mobile if adhesions/endometriosis; Usually no ascites; May not be palpable if small or soft. Special: complications, Meigs' syndrome |
| Ovarian cancer | General condition; Signs of metastasis (lymphadenopathy, DVT, pleural effusion, organomegaly, deposits in Pouch of Douglas); Ascites + abdominal/pelvic mass; Mobile/fixed non-tender mass arising from pelvis; Rectal exam |
Meigs' Syndrome — High Yield
Meigs' syndrome = ovarian fibroma (benign sex cord stromal tumour) + ascites + pleural effusion. It resolves completely after tumour removal. Important because it mimics ovarian cancer on presentation but is BENIGN. Don't confuse this with pseudo-Meigs' (any pelvic tumour + effusion).
Why does fibroid mass move with the cervix?
Because fibroids arise from the uterine myometrium. The cervix is the lower part of the uterus. When you push the cervix during bimanual exam, the entire uterus (and its fibroids) moves as one unit. An ovarian mass, being separate from the uterus, will NOT move with cervical excitation (unless adhered by endometriosis or malignancy).
Differential diagnoses for pelvic mass: [1]
| Category | Examples |
|---|---|
| Gynaecological | Uterine fibroid, adenomyosis; Pregnancy (undiagnosed, molar); Ovarian cyst, paraovarian cyst, hydrosalpinx; Malignancies: ovarian cancer, uterine sarcoma, metastatic |
| Gastrointestinal | Mesenteric cyst, tumour, hernia, diverticulum, dilated bowel |
| Urological | Distended bladder, diverticulum, pelvic kidney, transplanted kidney |
| Retroperitoneal | Sarcoma (usually not palpable) |
| Others | Pseudocyst, abscess |
Urgent DDx — Don't Miss These
Attend patients who need URGENT management: Shock, severe pain (peritoneal signs) → May require straight laparotomy. Exclude ovarian cyst complications and pregnancy complications. [1]
Always do a pregnancy test before any invasive investigation or surgery. An undiagnosed ectopic pregnancy presenting as pelvic pain + mass is a surgical emergency.
D. Investigations and Pelvic Imaging
Pelvic ultrasound is a common investigation tool. [1]
| Investigation | When to Use | Why |
|---|---|---|
| Pelvic USS | First-line for all pelvic masses | Non-invasive, no radiation, excellent for characterising cystic vs. solid, uterine vs. adnexal |
| Pregnancy test | Always in reproductive-age women | Exclude pregnancy before further workup or treatment |
| CBP | For menorrhagia | Assess degree of anaemia — guides urgency of management |
| CA-125 | Suspected ovarian cancer | Risk stratification (but low specificity — see below) |
| HE4 | With CA-125 for ROMA calculation | Better specificity than CA-125 alone, especially premenopausal |
| CT / MRI / PET-CT | Suspected ovarian cancer | Staging, surgical planning, detect metastases |
| Pre-operative work-up | Before planned surgery | ECG, CXR, bloods, group & save |
The most appropriate initial imaging test for pelvic pain in a young patient is ultrasound of the pelvis. This was directly tested in 2025 MCQ Q1. [4]
i. Fibroids (Leiomyomas) — Detailed
Most common neoplasms of the uterus. Develops in 20-40% of reproductive age women. Benign smooth muscle tumour. Usually multiple causing asymmetrical enlargement of the uterus. Cause mass effect on the myometrium and surface lobularity. [1]
Why are fibroids so common? They are oestrogen- and progesterone-dependent tumours. This explains why:
- They grow during reproductive years (high oestrogen)
- They may enlarge during pregnancy (high oestrogen)
- They shrink after menopause (declining oestrogen)
- GnRH agonists (which create a pseudo-menopausal state) can shrink them
Types: 1. Intramural; 2. Subserosal; 3. Submucosal; 4. Pedunculated; 5. Intraligamentary; 6. Parasitic; 7. Cervical [1]
| Type | Location | Clinical Significance |
|---|---|---|
| Intramural | Within myometrium | Most common; causes menorrhagia and bulk symptoms |
| Subserosal | Outer surface of uterus | Causes pressure symptoms but less menorrhagia; can mimic ovarian mass |
| Submucosal | Protrudes into uterine cavity | Most likely to cause heavy menstrual bleeding (even when small) and subfertility; can be removed hysteroscopically |
| Pedunculated | On a stalk (subserosal or submucosal) | Can undergo torsion → acute pain; pedunculated subserosal can be confused with ovarian mass |
| Intraligamentary | Between layers of broad ligament | Can be difficult to remove surgically; can obstruct ureter |
| Parasitic | Detached from uterus with alternative blood supply | Rare; can be found anywhere in pelvis |
| Cervical | In the cervix | Can cause dystocia in pregnancy; may prolapse through os |
Transvaginal — for small fibroids. Transabdominal — for large fibroids. Well-circumscribed; Pseudocapsule from surrounding compressed myometrium. Hypoechoic / heterogeneous echoes. [1]
- Sonohysterogram (saline infusion sonography) is used to assess submucosal fibroids — it outlines the uterine cavity to show how much of the fibroid protrudes into it.
- On USS, fibroids typically look like well-defined, hypoechoic masses within the myometrium with posterior acoustic shadowing (especially if calcified).
From radiology notes: a case of a 50/F with menorrhagia shows a uterine mass on transabdominal USS that is very vascular on Doppler — impression: leiomyoma. [6]
Degenerative changes: Hyaline, Myxoid, Calcific, Cystic, Hemorrhagic (red), Sarcomatous, Fatty [1]
| Degeneration | Mechanism & Clinical Relevance |
|---|---|
| Hyaline | Most common; replacement of muscle by hyaline tissue; usually asymptomatic |
| Myxoid | Gelatinous degeneration; can mimic malignancy on imaging |
| Calcific | Usually postmenopausal; visible on plain X-ray ("popcorn calcification") |
| Cystic | Follows hyaline/myxoid degeneration; creates fluid-filled spaces |
| Red (haemorrhagic) | Classically occurs in pregnancy when fibroid outgrows blood supply → venous thrombosis → haemorrhagic infarction → acute pain + tenderness + low-grade fever. This is the one time fibroids are tender. Managed conservatively (analgesia, NOT surgery). |
| Sarcomatous | Extremely rare ( < 1%); rapid growth, especially post-menopause, should raise suspicion. Uterine leiomyosarcoma. |
| Fatty | Rare; may be seen on CT |
Red Degeneration — Exam Favourite
Red degeneration is the classic cause of painful fibroid in pregnancy. It presents with acute localised uterine tenderness, low-grade fever, and mildly elevated WBC. Treatment is conservative (rest, hydration, analgesia — paracetamol, avoid NSAIDs in pregnancy). Do NOT operate unless diagnosis is uncertain.
ii. Adnexal Masses — Ovarian Cysts and Cancer
Types of benign ovarian masses: [1]
| Category | Entities |
|---|---|
| Functional | Follicular cyst, corpus luteal cyst, theca luteal cyst |
| Inflammatory | Endometriotic cyst, tuboovarian abscess |
| Germ cell | Mature teratoma (dermoid cyst) |
| Epithelial | Serous cystadenoma, mucinous cystadenoma, clear cell cystadenoma |
| Sex cord stromal | Fibroma, thecoma |
| Others | Ovarian ectopic |
Functional cysts are the most common ovarian cysts in premenopausal women. They arise from normal ovulatory physiology:
- Follicular cyst: A follicle fails to rupture or fails to regress → continues to fill with fluid → usually resolves spontaneously within 2-3 cycles
- Corpus luteal cyst: The corpus luteum fails to regress → can cause delayed menstruation (mimicking pregnancy) → may rupture causing haemoperitoneum
- Theca luteal cyst: Associated with high β-hCG levels (molar pregnancy, multiple pregnancy, ovarian hyperstimulation)
Endometriotic cyst (endometrioma / "chocolate cyst"): Contains old blood → ground glass appearance on USS → classic for endometriosis. DDx for dysmenorrhoea + subfertility + pelvic pain.
Mature teratoma (dermoid cyst): Contains tissues from all three germ layers (hair, teeth, sebum, thyroid tissue). USS shows mixed echogenicity, fat-fluid levels, Rokitansky nodule. X-ray may show teeth. Most common ovarian tumour in young women. Risk of torsion because of its weight. [6]
The lecture references a classification slide. The main categories are:
| Category | Subtypes | Key Features |
|---|---|---|
| Epithelial (~90% of ovarian cancers) | High-grade serous (most common), Low-grade serous, Mucinous, Endometrioid, Clear cell | Most are diagnosed late (Stage III/IV). BRCA1/2 mutations strongly associated with high-grade serous. |
| Germ cell | Dysgerminoma, Immature teratoma, Yolk sac tumour, Choriocarcinoma | Young women; good prognosis with chemotherapy; check AFP, β-hCG, LDH |
| Sex cord stromal | Granulosa cell tumour, Sertoli-Leydig cell tumour, Fibroma | May produce hormones (oestrogen → endometrial hyperplasia, androgens → virilisation) |
| Metastatic | Krukenberg tumour (from stomach/colon), breast, lymphoma | Bilateral, solid masses. Always exclude GI primary! |
Cyst content: [1]
- Anechoic (black) — simple fluid; most likely benign
- Low-level echoes — homogeneous low echogenicity; may be mucinous or haemorrhagic
- Ground glass appearance — homogeneous dense echoes; classic for endometrioma
- Hemorrhagic — thread-like fibrin strands; corpus luteal cyst or haemorrhagic cyst
- Mixed (heterogeneous) — as seen in teratoma
- Mixed with blood-fluid or fat-fluid level — teratoma
- Mixed (abscess) — tuboovarian abscess
Unilocular-solid cyst → Multilocular cyst → Multilocular-solid cyst with papillary projection → Solid tumour [1]
As you move along this spectrum, malignancy risk increases. A simple unilocular anechoic cyst is almost certainly benign. A multilocular-solid cyst with papillary projections and Doppler flow is highly suspicious for malignancy.
Indicators of malignancy: Papillary projections ( > 3 mm in height); Solid-cystic masses; Strong intratumoral colour flow [1]
| Feature | Suggests Benign | Suggests Malignant |
|---|---|---|
| Walls | Thin, smooth | Thick, irregular |
| Septations | Thin ( < 3 mm) | Thick ( > 3 mm) |
| Content | Anechoic/ground glass | Solid components, mixed |
| Papillary projections | Absent | Present ( > 3 mm) |
| Doppler flow | Absent/peripheral | Strong intratumoral flow |
| Laterality | Unilateral | Bilateral |
| Ascites | Absent | Present |
Risk Stratification Tools
IOTA (International Ovarian Tumor Analysis) simple rules: [1]
- Classified MALIGNANT: at least 1 M feature and no B feature
- Classified BENIGN: at least 1 B feature and no M feature
- Inconclusive: if no B or M features present, or if both B and M features are present Sensitivity 95%, specificity 91%, positive likelihood ratio 10.37, negative likelihood ratio 0.06 [1]
IOTA B-rules (benign features):
- Unilocular cyst
- Solid component where largest solid component < 7 mm
- Acoustic shadows
- Smooth multilocular tumour < 100 mm
- No blood flow (colour score 1)
IOTA M-rules (malignant features):
- Irregular solid tumour
- Ascites
- At least 4 papillary structures
- Irregular multilocular-solid tumour ≥ 100 mm
- Very strong blood flow (colour score 4)
RMI I sensitivity 78% (95% CI 71-85%), specificity 87% (95% CI 83-91%) [1]
RMI = U × M × CA-125
Where:
- U = Ultrasound score: 0 points if 0 features; 1 point if 1 feature; 3 points if ≥2 features (features: multilocular, solid areas, bilateral, ascites, metastases)
- M = Menopausal status: 1 if premenopausal; 3 if postmenopausal
- CA-125 = serum level in U/mL
| RMI Score | Interpretation |
|---|---|
| < 25 | Low risk |
| 25-250 | Moderate risk |
| > 250 | High risk → refer to gynae-oncology centre |
This was tested in 2022 SAQ Q12(e): "Name the score to guide further management" → RMI [3]
RMI — Why the Formula Works
The RMI multiplies three independent risk factors: ultrasound features (morphology), menopausal status (baseline risk), and CA-125 (biomarker). Postmenopausal women get a higher multiplier (M=3) because any ovarian mass in a postmenopausal woman has a higher prior probability of malignancy (ovaries should be quiescent). This is also why CA-125 is more specific in postmenopausal women — fewer confounding causes of elevation.
Celomic epithelium related glycoprotein. Present in most serous, endometrioid, and clear cell ovarian carcinomas. Mucinous tumours express it less frequently. Also found in epithelium of fallopian tubes, endometrium, and uterine cervix. [1]
Usual cut-off: 35 U/mL. Low specificity. More sensitive and specific in postmenopausal women. More useful in follow-up of patients after treatment for proven CA ovary and with elevated CA-125 level before treatment. [1]
Causes of Elevated CA-125 (Exam Favourite!)
Elevated in: [1]
- Menstruating and pregnant women
- Benign ovarian tumours (10%)
- Endometriosis (20-30%)
- Acute PID
- Fibroids
- Liver cirrhosis (60-70%)
- Pancreatitis (30%)
- etc.
CA-125 — The Specificity Trap
CA-125 has low specificity, especially in premenopausal women. Many benign conditions elevate it. A raised CA-125 in a 25-year-old with a pelvic mass is far more likely to be endometriosis or PID than ovarian cancer. In contrast, in a postmenopausal woman with ascites and a complex adnexal mass, an elevated CA-125 is much more meaningful. The lecture explicitly states CA-125 is most useful for follow-up after treatment, not as a screening tool.
This was tested: 2022 SAQ Q12(b): "What is the most appropriate blood test to confirm the diagnosis of her pelvic mass [ovarian cancer]?" → CA-125 [3]
ROMA uses a predictive index (PI) combining HE4 and CA-125: [1]
- Premenopausal: PI = −12 + 2.38 × LN[HE4] + 0.0626 × LN[CA-125]
- Postmenopausal: PI = −8.09 + 1.04 × LN[HE4] + 0.732 × LN[CA-125] ROMA = exp(PI) / [1 + exp(PI)] × 100
| Premenopausal | Postmenopausal | |
|---|---|---|
| Low-risk | *** < 11.4%*** | *** < 29.9%*** |
| High-risk | ≥ 11.4% | ≥ 29.9% |
| Sensitivity | 100.0% | 89.5% |
| Specificity | 77.6% | 82.8% |
| PPV | 15.0% | 57.6% |
| NPV | 100.0% | 96.7% |
Why does ROMA include HE4? HE4 (Human Epididymis protein 4) is less frequently elevated in benign conditions compared to CA-125. Adding HE4 improves specificity, especially in premenopausal women where CA-125 alone performs poorly.
Note the 100% sensitivity and 100% NPV in premenopausal women — ROMA is excellent at ruling OUT ovarian cancer in this group (if low-risk, you can be very confident it's benign).
ADNEX Model is referenced by the lecture as another risk stratification tool. [1]
The IOTA ADNEX model uses multiple ultrasound parameters plus CA-125 to provide probabilities for: benign, borderline, stage I cancer, stage II-IV cancer, and secondary metastatic cancer. It is available as an online calculator. Know that it exists and is more granular than RMI.
| Modality | Role in Pelvic Mass |
|---|---|
| Pelvic USS | First-line for all pelvic masses |
| CT abdomen/pelvis/chest | Staging for suspected ovarian cancer — detect omental cake, peritoneal deposits, lymphadenopathy, liver mets, pleural effusion |
| MRI pelvis | Better soft tissue characterisation — useful for complex adnexal masses (indeterminate on USS), fibroid mapping pre-surgery, adenomyosis |
| PET-CT | Staging, restaging, monitoring treatment in ovarian cancer; uses 18F-FDG [7] |
| Plain X-ray | May show calcified fibroid or teeth in dermoid cyst |
From interventional radiology notes: uterine artery embolisation (UAE) is an IR procedure for fibroids — particles are injected into uterine arteries to devascularise fibroids, causing them to shrink. [8]
E. Management
Management principles: Review history, physical examination; Review investigation results, diagnosis, +/- previous treatment; Benign/malignant; acute/chronic; Presence of symptoms/signs; Patient's fitness; Patient's wishes; Individualised. [1]
Fibroids: [1]
- Asymptomatic — observation
- Symptomatic:
- a. Symptomatic relief: e.g., tranexamic acid (Transamin), Mirena IUS
- b. Surgical removal: myomectomy vs. hysterectomy; approach: open/laparoscopic/vaginal/hysteroscopic
- c. Other modalities: uterine artery embolisation (UAE), high-intensity focused ultrasound (HIFU)
| Treatment | Indication | Key Points |
|---|---|---|
| Observation | Asymptomatic, small fibroids | Most fibroids don't need treatment; will shrink after menopause |
| Tranexamic acid | Menorrhagia | Antifibrinolytic — reduces bleeding by 40-50%; does NOT shrink fibroids |
| Mirena IUS | Menorrhagia; also contraception | Releases levonorgestrel → endometrial thinning → reduces bleeding; does NOT shrink fibroids but excellent symptom control |
| GnRH agonists | Pre-operative shrinkage; bridge to menopause | Creates pseudo-menopausal state → fibroids shrink 40-60%; max 6 months due to bone loss; rebound growth after stopping |
| Myomectomy | Fertility preservation desired | Can be done laparoscopically, hysteroscopically (submucosal), or open; risk of recurrence |
| Hysterectomy | Definitive treatment; family complete | Total abdominal hysterectomy (TAH), laparoscopic, vaginal approach |
| UAE | Alternative to surgery; preserve uterus | Interventional radiology procedure; 80-90% symptom improvement; risk of post-embolisation syndrome (pain, fever) |
| HIFU | Non-invasive; outpatient | Focused ultrasound ablation guided by MRI or USS; destroys fibroid tissue thermally |
From 2018 SAQ Q11: A 46-year-old with heavy menstrual bleeding → physical exam focus (abdominal exam for mass, pelvic exam), investigations (CBP, pelvic USS, endometrial sampling), DDx (fibroid, adenomyosis), complications of hysterectomy (haemorrhage, infection, injury to ureter/bladder/bowel, VTE, vaginal vault prolapse). [2]
Hysterectomy Complications — Exam Must-Know
- Intraoperative: Haemorrhage, injury to bladder, ureter, or bowel
- Early postoperative: Infection (wound, pelvic, UTI), VTE, secondary haemorrhage
- Late: Vaginal vault prolapse, premature menopause (if ovaries removed), psychosexual issues
Premenopausal: [1]
- Asymptomatic: can observe and repeat ultrasound (3-6 months)
- Symptomatic: possible complications, needs removal
- Persistent cyst: consider removal to confirm diagnosis (cystectomy vs. salpingo-oophorectomy; laparoscopy vs. laparotomy)
- Suspected cancer: refer oncology, exclude secondary from colon, stomach, breast etc., staging surgery +/- chemotherapy
Why observe functional cysts? Most functional cysts (follicular, corpus luteal) resolve spontaneously within 2-3 menstrual cycles. Repeating USS in 3-6 months confirms resolution. A cyst that persists beyond this is no longer "functional" and warrants further evaluation or removal.
Conservative management criteria (ALL must be met): [1]
- Simple
- Unilateral
- Unilocular cyst < 5 cm
- Normal CA-125
- Unchanged after serial assessment
All other cysts should be removed (generally BSO, laparotomy or laparoscopy)
Why is the threshold lower for postmenopausal women? After menopause, ovaries should be quiescent — there should be no new functional cysts. Any new ovarian mass carries a higher prior probability of malignancy. Hence, only the simplest, smallest cysts with normal markers can be safely observed.
Why BSO (bilateral salpingo-oophorectomy)? In postmenopausal women, there is no fertility to preserve. Removing both ovaries and tubes reduces future ovarian cancer risk and eliminates the need for future surgery on the contralateral ovary.
Depends on stage and fitness of patients: [1]
- Early stage: surgery +/- chemotherapy
- Late stage: surgery AND chemotherapy +/- targeted therapy
Surgical principles for ovarian cancer:
- Staging surgery (early stage): Total abdominal hysterectomy (TAH), bilateral salpingo-oophorectomy (BSO), omentectomy, peritoneal washings/biopsies, pelvic + para-aortic lymph node sampling
- Debulking/cytoreductive surgery (late stage): Aim for optimal debulking (no residual disease > 1 cm). Complete gross resection correlates with better survival.
- Chemotherapy: Platinum-based (carboplatin) + paclitaxel is standard first-line
- Targeted therapy: PARP inhibitors (e.g., olaparib) for BRCA-mutated tumours; bevacizumab (anti-VEGF)
From molecular pathology: BRCA1/BRCA2 germline mutation testing is recommended for all high-grade serous ovarian carcinoma patients — this guides use of PARP inhibitors AND has implications for family screening. [9][10]
From 2021 SAQ Q2: Applications of molecular genetic testing in gynaecological cancers — BRCA testing in ovarian cancer, MMR/MSI testing in endometrial cancer, FOXL2 in granulosa cell tumours, DICER1 in Sertoli-Leydig cell tumours. [11]
| Complication | Presentation | Management |
|---|---|---|
| Torsion | Sudden severe unilateral pelvic pain, nausea/vomiting, adnexal tenderness, may have peritonism | Emergency laparoscopy → untwist (detorsion) if viable; oophorectomy if necrotic |
| Rupture | Sudden pain, may have haemoperitoneum and hypovolaemic shock | Supportive if haemodynamically stable; laparoscopy/laparotomy if significant bleeding |
| Haemorrhage (into cyst) | Acute pain, enlarging mass | Usually conservative; surgery if unstable |
| Infection | Fever, pelvic tenderness, purulent discharge | Antibiotics; drainage if tuboovarian abscess |
From 2024 MCQ Q13: Pelvic pain + 8 weeks amenorrhoea + heterogeneous mass separate from ovary + fluid in POD → this is an ectopic pregnancy scenario, not a simple ovarian cyst. The correct answer required serial βhCG and/or diagnostic laparoscopy depending on clinical stability. [12]
| Imaging | First-line? | Strengths | Limitations |
|---|---|---|---|
| Pelvic USS (TVS + TAS) | YES | No radiation, readily available, excellent for cyst characterisation, cheap | Operator-dependent, limited by body habitus, gas |
| Sonohysterogram | For submucosal pathology | Outlines uterine cavity with saline; excellent for submucosal fibroids/polyps | Invasive, requires patent cervix |
| MRI pelvis | Second-line | Superior soft tissue contrast, fibroid mapping, adenomyosis, indeterminate masses | Expensive, not always available, no real-time |
| CT abdomen/pelvis | Staging | Detects metastases, lymphadenopathy, omental cake | Radiation, poor soft tissue contrast in pelvis cf. MRI |
| PET-CT | Staging/restaging | Functional + anatomical; detects metabolically active disease | Expensive, radiation, false positives with inflammation |
| Plain X-ray (AXR) | Not routine | Can show calcified fibroid, teeth in dermoid | Low sensitivity |
Uterine fibroid, ovarian mass and cancer are important differential diagnoses of pelvic mass. History and physical examination usually help to suggest a diagnosis. Pelvic ultrasound is commonly performed. Management will depend on the age, symptom, condition and wish of the patient. [1]
Based on past papers (2018 SAQ Q11, 2019 SAQ Q1, 2020 minicase, 2021 MCQ Q14-16, 2022 SAQ Q12, 2024 MCQ Q13, 2025 MCQ Q1) and lecture content:
-
SAQ: "A 55-year-old postmenopausal woman presents with abdominal distension. USS shows a multiloculated pelvic mass with solid areas and free fluid in POD."
- (a) Most likely diagnosis → Ovarian cancer
- (b) Most appropriate blood test → CA-125
- (c) Name 5 USS features to assess → Size, bilateral/unilateral, cystic/solid content, septations, ascites, Doppler flow
- (d) Management of distension → Treat the underlying cause; staging surgery (TAH + BSO + omentectomy) +/- neoadjuvant chemotherapy. For symptomatic ascites: therapeutic paracentesis.
- (e) Score to guide management → RMI (Risk of Malignancy Index)
-
MCQ: Which imaging modality is most appropriate for initial assessment of pelvic mass → Pelvic ultrasound (not CT, not MRI)
-
SAQ: "46-year-old with heavy menstrual bleeding, uterus 14-week size on exam. Name 2 DDx." → Fibroid, adenomyosis (also consider endometrial polyp, endometrial hyperplasia)
-
MCQ/SAQ: "Name conditions that elevate CA-125 other than ovarian cancer" → Endometriosis, PID, fibroids, liver cirrhosis, pregnancy, menstruation, pancreatitis
-
Minicase/OSCE: Approach to pelvic mass — structured history + exam + DDx + investigation plan
-
MCQ: Postmenopausal ovarian cyst that can be observed → Must be simple, unilateral, unilocular, < 5 cm, normal CA-125, unchanged on serial assessment
High Yield Summary
Pelvic mass = Fibroid vs. Ovarian cyst vs. Ovarian cancer until proven otherwise in a gynaecological context.
Always do a pregnancy test.
Fibroid: Most common uterine neoplasm. Firm, rubbery, moves with cervix. Menorrhagia is the key symptom. USS: well-circumscribed, hypoechoic, pseudocapsule. Types: intramural (commonest), submucosal (most bleeding), subserosal (pressure), pedunculated (torsion risk). Red degeneration = painful fibroid in pregnancy. Mx: observe if asymptomatic; tranexamic acid/Mirena/GnRH agonists for symptoms; myomectomy/hysterectomy/UAE/HIFU for definitive treatment.
Ovarian cyst: Functional cysts resolve in 2-3 cycles → repeat USS in 3-6 months. Complications = torsion, rupture, haemorrhage. Endometrioma = ground glass on USS. Dermoid = mixed echoes, fat-fluid level, teeth on X-ray. Postmenopausal cyst: conservative only if simple + unilateral + unilocular + < 5 cm + normal CA-125 + unchanged on serial USS.
Ovarian cancer: Often presents late with non-specific GI symptoms, distension (ascites), weight loss. USS: solid-cystic, papillary projections > 3 mm, strong Doppler flow, ascites. CA-125 (cut-off 35 U/mL) — low specificity premenopausal, better postmenopausal. IOTA simple rules (B/M features), RMI (U × M × CA-125), ROMA (CA-125 + HE4). Management: early stage = surgery ± chemo; late stage = surgery + chemo ± targeted therapy (PARP inhibitors for BRCA+).
Pelvic USS is the first-line imaging for all pelvic masses.
Active Recall - Pelvic Mass, Ovarian Cancer & Cysts, Uterine Fibroids, Pelvic Imaging
[1] Lecture slides: GC 118. Pelvic mass ovarian cancer and cysts; uterine fibroid; pelvic imaging.pdf (all pages) [2] Past papers: 2018 Fourth Summative SAQ.pdf (Question 11) [3] Past papers: 2022 Fourth Summative SAQ.pdf (Question 12) [4] Past papers: 2025 Fourth Summative MCQ.pdf (Question 1) [5] Senior notes: Ryan Ho Fundamentals.pdf (p76-77, Approach to Palpable Mass) [6] Senior notes: Ryan Ho Radiology.pdf (p33, Pelvic imaging cases) [7] Senior notes: Ryan Ho Diagnostic Radiology.pdf (p74, PET-CT applications) [8] Lecture slides: IR 2025_VLau.pdf (p10, Interventional radiology for fibroids) [9] AOS material: AOS - Pathology.pdf (p20, Molecular genetic testing in gynaecological cancers) [10] Lecture slides: Molecular Pathology Seminar 7_Molecular genetic testing in gynaecological cancers_Sept 2023 Handout.pdf [11] Past papers: 2021 Fourth Summative SAQ.pdf (Question 2) [12] Past papers: 2024 Fourth Summative MCQ.pdf (Question 13)
GC117 I Want To Have A Baby Male And Female Infertility
Male and female infertility refers to the inability of a couple to achieve pregnancy after 12 months of regular unprotected intercourse, resulting from disorders of sperm production or function, ovulatory dysfunction, tubal damage, uterine abnormalities, or unexplained factors in either partner.
GC119 Vaginal Discharge Obstetric And Gynaecological Infections
Vaginal discharge resulting from obstetric and gynaecological infections encompasses abnormal genital tract secretions caused by pathogens such as Candida, bacterial vaginosis organisms, Trichomonas, Chlamydia, or Neisseria gonorrhoeae during pregnancy or in the gynaecological setting, requiring prompt identification and treatment to prevent complications.