Ovarian tumours + cysts

Question 1

Ovarian cysts

Answer 1

1. Physiological (follicular cyst, corpus luteal cyst)

2. Pathological cysts (endometrioma, cystic component of benign or malignant ovarian neoplasms)

Question 2

Non-neoplastic cysts

Answer 2

Physiological

1. Follicular cysts (normally

Question 3

Benign neoplastic tumours

Answer 3

Epithelial tumours

1. Serous cystadenoma (usually unilocular and 20-30% are bilateral, may have septations)
2. Mucinous cystadenoma (often multiloculated, but usually unilateral, can get extremely large, >150kg)
3. Brenner tumours (1-2% of ovarian tumours, unilateral, and have solid grey, white or yellow appearance to cut surface, fibrous elements and transitional epithelium)

Other

4. Benign germ cell tumours (mature teratoma or dermoid cyst) - 10% bilateral, 90% in women of reproductive age, usually full of sebaceous material and hair, but may contain teeth, skin, cartilage, fat or bone; can cause chemical peritonitis if contents spill
5. Sex-cord stromal tumours (rare) - e.g. fibroma

Question 4

Benign ovarian cysts - presentation + general management

Answer 4

1. Most cysts presenting acutely will present with lower abdominal pain, but without signs of peritonism or systemic upset -> manage conservatively with analgesia; most will resolve spontaneously
2. If the woman presents with an acute abdomen +/- signs of systemic upset, due to ovarian torsion, rupture or haemorrhage of a cyst, urgent diagnostic laparoscopy or laparotomy may be required`

Question 5

Benign ovarian cysts - ix and mx (adolescent/premenopausal women)

Answer 5

1. Perform USS and CA125. Calculate RMI and rescan in 6 weeks. Note - transvaginal cyst aspiration under USS guidance has no advantage over expectant management
2. If cyst still persists or is >5cm, consider laparoscopic cystectomy
   3, If cyst 5cm or is a dermoid, aim to prevent spillage of contents (e.g. cystectomy and removal of cyst in an ‘endobag’)
3. If suspicious findings at laparoscopy, abandon procedure (take peritoneal biopsy for dx), refer to cancer centre for full staging laparotomy

Question 6

Benign ovarian cysts - ix/mx (post-menopausal women)

Answer 6

1. TVUSS, CA125 - calculate RMI

If low RMI (250):
1. Refer to cancer centre for full staging laparotomy

Question 7

Ovarian cancer - histology

Answer 7

• The ovary is a collection of several different cell types, each of which can have neoplastic development
• But 90% are epithelial ovarian cancers and are commonly referred to as ovarian cancer

Question 8

Ovarian cancer - incidence

Answer 8

Peak incidence is in women aged 75-84y

Question 9

Ovarian cancer - etiology

Answer 9

Believed to be due to irritation of ovarian surface epithelium by damage due to ovulation; increased risk if multiple ovulations and decreased risk if ovulation suppressed

Question 10

Ovarian cancer - risk factors

Answer 10

1. Nulliparity
2. Early menarche
3. Late menopause
4. BRCA 1 and BRCA 2 mutations (also lead to increased risk of breast cancer)
5. HNPCC (Lynch II syndrome) - rarer than BRCA1 and BRCA2 mutations

Question 11

Ovarian cancer - protective factors (2)

Answer 11

1. COCP

2. Pregnancy

Question 12

Ovarian cancer - presentation

Answer 12

Often present with a range of vague, common symptoms, which may be interpreted as other conditions, e.g. irritable bowel syndrome or diverticular disease

1. Abdominal distension (often described as bloating, but persistent)
2. Increased girth
3. Urinary symptoms
4. Change in bowel habit
5. Abnormal vaginal bleeding

Question 13

Ovarian cancer - ex

Answer 13

1. Pelvic/abodminal mass (fixed/mobile)
2. Ascites
3. Omental mass (common site for metastasis, may involve whole omentum - omental cake)
4. Pleural effusion
5. Supraclavicular lymph nodes

Question 14

Ovarian cancer - ix

Answer 14

1. FBE, UEC, LFTs, albumin
2. Tumour markers - CA125 (increased in 80% of epithelial cancers, calculate RMI), CEA (carcinoembryonic antigen - raised in colorectal cancer but normal in ovarian cancer), CA19.9 (may be raised in mucinous tumours, which are also more likely to have normal CA125 (also raised in pancreatic and breast cancer), tumour markers for rarer ovarian tumours if appropriate (AFP, hCG, LDH, inhibin, estradiol)

Imaging

3. Abdominal/pelvic U/S (presence of pelvic mass and ascites)
4. CXR (pleural effusion or lung metastases - for staging and preoperative work up)
5. CT abdomen/pelvis - omental caking, peritoneal implants, liver metastases, para-aortic lymph nodes

Question 15

Ovarian cancer - mx of ascites and pleural effusion

Answer 15

Diagnosis
1. Ascitic/pleural fluid should be sampled and sent for cytology, microbiology and biochemistry

Symptom control

2. Drainage of massive tense ascites or a pleural effusion preoperatively
3. For ascitic drainage use a pig-tail drain, aseptic technique and instill LA into skin and through abdominal wall
4. U/S guidance, especially if bowel metastases are suspected or previous abdominal surgery
5. Albumin may decrease precipitously following ascitic drainage (suggest dietitian referral and the use of high-protein supplements to avoid problems with hypoalbuminaemia and severe generalised oedema)

Question 16

Ovarian cancer - mx

Answer 16

1. Staging laparotomy performed through midline incision
2. Ideally performed at cancer centre by gynaecological oncologist
3. Laparotomy should aim to remove as much tumour as possible - ideally with no macroscopic tumour remaining (survival directly related to amount of residual disease)
4. Six cycles of cytotoxic chemotherapy - combination of carboplatinum + paclitaxel
5. If disease left behind, tumour response evaluated by imaging studies. If no residual disease, CA125 useful to ensure chemotherapy is effective

Question 17

Borderline epithelial tumours - overview

Answer 17

1. 15% of all ovarian tumours
2. Usually of serous or mucinous type where the glandular cells are clearly neoplastic, but this does not present with invasion into the ovarian stroma
3. Uncommon for spread to occur outside the ovary
4. Mx = removal of tumours without the need for a more extensive staging approach
5. Adjuvant tx not required unless there are invasive implants detected from borderline tumours

Question 18

Germ cell tumours - background (3)

Answer 18

1. Can arise anywhere down tract of embryological genital ridge, but most occur in the ovaries
2. Degree of differentiation of primordial germ cell affects the type of tumour produced
   a. Undifferentiated germ cells = dysgerminoma
   b. Cells that have undergone initial differentiation can undergo embryonal or extra-embryonal differentiation, to produce choriocarcinoma/endodermal sinus tumours (yolk sac) or teratomas, respectively
3. Most commonly occur in young women; account for 70% of ovarian tumours in under 20s

What about dermoid cysts?

Question 19

Germ cell tumours - classification

Answer 19

Three broad categories:

1. Primitive germ cell tumours
2. Biphasic or triphasic teratomas
3. Monodermal teratomas (rare) and somatic-type tumours associated with dermoid cysts

Question 20

Primitive germ cell tumours - subtypes

Answer 20

Six recognised subtypes; these contain malignant germ cell elements other than teratoma

1. Dysgerminoma
2. Yolk sac tumour
3. Embryonal carcinoma (rare)
4. Polyembryoma (rare)
5. Non-gestational choriocarcinoma (rare)
6. Mixed germ cell tumour (composed of at least two different germ cell elements)

Question 21

Biphasic and triphasic teratomas - subtypes

Answer 21

Most common of the ovarian germ cell tumours. Composed of derivatives of two or three primary germ layers - ectoderm, mesoderm or endoderm (can give rise to any tissue that may be seen in the body). Divided into immature and mature subtypes, which also correlates with malignant or benign nature

1. Immature teratomas - tumours that contain a varying amount of immature tissue
2. Mature teratoma or ovarian dermoid cysts - benign cysts composed of mature tissues, most frequently sebaceous material, hair and bone (present at any age from 2-80y, mean age 32y); ovarian torsion is a common cause for presentation

Question 22

Monodermal teratomas - background

Answer 22

1. Rare group of tumours made up of teratomas comprised of a single tissue type, derived from one embryonic layer (include struma ovarii - mature teratomas containing thyroid tissue that may be benign or malignant)

Question 23

Germ cell tumours - presentation

Answer 23

Variable

1. May be non-specific with abdominal distension
2. May have finding of a mass with associated bladder or bowel symptoms
3. May cause severe abdominal pain, particularly when associated with ovarian torsion or cyst rupture
4. Tumours that release hCG may present with menstrual irregularities or symptoms of pregnancy such as nausea and breast tenderness
5. > 2/3 of malignant germ cell tumours are stage I at the time of dx, involving the ovary only (metastasis via peritoneal spread or lymphatic system)

Question 24

Germ cell tumours - ix

Answer 24

1. Tumour markers - CA125, CA19.9, alpha fetoprotein (AFP), beta hCG, lactate dehydrogenase (LDH)
2. FBE, UEC, LFTs (?)
3. Pelvic ultrasound (transvaginal where appropriate

Once malignant germ cell tumour suspected:

4. CT abdomen, pelvis
5. CXR or CT chest

Question 25

Germ cell tumours - mx

Answer 25

1. Dermoid cysts = simple cystectomy (conserving the ipsilateral ovary)
2. For suspected malignant germ cell tumours, surgery including peritoneal washings for cytology, unilateral salpingo-oophorectomy, omental and peritoneal biopsies, and biopsies of any suspicious lesions in abdomen and pelvis
3. All malignant ovarian germ cell tumours need adjuvant chemotherapy = bleomycin + etoposide + cisplatin (except stage Ia dysgerminomas and well-differentiated stage Ia, immature teratomas)
4. Following dx and tx, review pt every 2-4mo for the first 2y and yearly thereafter, until 10y post-tx (hx, ex, evaluation of all tumour markers, U/S or radiological imaging if raised tumour markers/ symptomatic/ suspicious examination findings)
5. Persistent disease following chemotherapy requires second-line chemotherapy rather than surgery

Note - overall 10y survival is high at 90%