Ovarian Cancer and Ovarian Cysts😊

Types of Ovarian Cancer (WHO Classification)

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Epithelial ovarian tumor
(
m/c : 90%)
CA 125 (Tumor marker for all)
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Serous tumor (m/c)
• BRCA1
• In elderly
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Mucinous tumor
CEA > Ca 19-9
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Brenner tumor
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Endometrioid tumor
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Clear cell Ca
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Germ cell tumor
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Teratoma/dermoid cyst
• Malignant/immature
• Benign/mature cystic
↳
m/c teratoma
↳
MC germ cell tumor
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Dysgerminoma
MC malignant germ cell tumor
Markers
• LDH >>
• PLAP
• hCG
• OCT3/4, NANOG

Never Produce: AFP
Daughter in LH → LDH, HCG → For PLAB → No Protein (AFP)

Daughter/Son (Seminoma)
Yolk sac tumor
(
Endodermal sinus tumour)
AFP > LDH

Never Produce: hCG
Y’all → AFP >> LDH

Yolk → to all → except HEN (HCG)

Protein kittan (afp) → Yolk eduthitt (yolk sac) → 2 times chill (duval schiller) cheyth
Embryonal cancer
AFP + hCG + CD30
Embryo ondavumbo → AFP, hcg
Choriocarcinoma
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ch → hc → HCG
Sex cord stromal tumor:
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↳ Estrogen secreting
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Granulosa cell tumor
Inhibin B & AMH
Granpa In (Inhibin) Aunties (Antimullarian) house
↳ Androgen secreting
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Arrhenoblastoma/Adenoblastoma
m/c virilising tumor of ovary
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Sertoli cell
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Leydig cell
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Hilus cell tumor
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↳ Stromal tumor:
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Fibroma
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Thecoma
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Fibrothecoma
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Metastatic tumor:

  • Krukenberg tumor
    • Stomach > Breast/ Colon
    • Signet Ring Cells
    • Retrograde lymphatic spread

p53 and Gyne Cancers

  • Ca Cervix
    • E6 → P53
    • E7 → Rb gene
  • Ca Ovary
    • Serous cystadenocarcinoma
      • p53 (90%) m/c
      • BRCA1 (10%)
  • Type 2 Endometrial Ca

m/c ovarian tumor a/w

  • Endometriosis:
    • Clear cell Ca > endometrioid tumor.
    • Endometriosis → Clear the problem
  • Endometrial Ca:
    • Endometrioid tumor > granulosa cell tumor.
    • Oid → tumor

Note

  • Only 2 solid benign tumors of ovary
    • Brenner
    • Fibroma
  • Mnemonic: Solid FiBre (Fibroma, Brunners)
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Screening of Ovarian Cancer

  • Not done universally.
  • Indication:
    • H/o familial ovarian Ca (10%).
      • Family history (1st degree relative):
      • Occurs a decade earlier (5th decade).
        ↓
  • BRCA gene 1/2 testing

    ↓ (if positive)
 
  • Perform TAH + BSO once family is complete OR
    patient
    >40 years of age.

    ↓
  • Screening with TVS + CA 125 annually.

Protocol for Adnexal Mass on P/V

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  • TVS (Next step).
  • Features suggestive of malignancy:
      1. Solid component.
      1. Bilateral.
      1. Papillary excrescences.
      1. Thick septa.
      1. Increased vascularity in septa.
      1. Ascites/LN involvement/matted bowel loop.

Types of Ovarian Tumors

Epithelial Ovarian Tumors

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  • m/c ovarian tumors.
  • m/c type: Serous cystadenoma Ca.
  • Seen in >60 years.
  • Mostly unilateral.
  • Mutations:
    • Low grade tumors: KRAS/PTEN.
    • High grade tumors: p53.
  • Ovarian Ca a/w pseudomyxoma peritonei: mucinous tumor.
Tumor Type
Key Characteristics / Associations
Microscopy
Mnemonic
Serous Ovarian
Single cyst, 
Serous fluid
c(S)iliated epithelium, 
pSammoma bodies.
SSS
Mucinous Ovarian
Multiple cysts, 
Mucinous fluid
Mucinous epithelium (empty cells)
MMM
Brenner Tumor
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Bladder (transitional) epithelium
Beans (
Coffee bean nuclei)
BBB
Clear Cell Tumor
A/w DES daughters.
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Endometrioid Type
A/w endometriosis.
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Prognosis

  • Not good.
  • Non-specific signs & symptoms initially.
  • Present in advanced stage directly.

Pseudomyxoma peritonei

  • Causes:
    • Appendix Ca (m/c).
    • Mucinous ovarian tumor.
    • Mucocele of appendix.
  • ↑↑ recurrence rate: Bad prognosis.

Syndromes a/w Ascites & Right Side Pleural Effusion

Meigs's syndrome:

  • Any 1 of the following
    • Fibroma >>
    • Granulosa cell tumor.
    • Brenner tumor (Solid benign tumor).
    • Thecoma.
  • Mnemonic:
    • The (thecoma) Baby (Brennur) in Family (Fibroma) Guy (Granulosa)
      • notion image

Pseudo Meig Syndrome

  • When associated with any other condition
    • (Eg: Fibroids, mucinous ovarian tumors).

Brenner's Tumor

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Features

  • Epithelial cell type
  • Solid consistency
    • Mnemonic: FiBre (Fibroma, Brunner)
  • Unilateral (U/L)
  • Benign tumor

Histopathology (HPE)

  • Coffee bean nucleus present
  • Walthard cell nest present
    • notion image

Epithelium

  • Transitional epithelium
  • Mnemonic:
    • Valathi kili cell nest (Walthard cell nest) → Bru coffee (Coffe bean)
    • BBBB → Bruners, Bladder epi, bfenign, Bean (coffee bean)

Germ Cell Tumor (GCT)

Demographics

  • Common age group: 10–30 years

Laterality

  • Mostly unilateral (U/L)
    • Always U/L:
      • Yolk sac tumor
        • Mnemonic: Yolk → Y → Yuni → unilateral
    • Bilateral (B/L) in:
      • 2-10% of dermoid cysts
      • 15-20% of dysgerminomas

Most Common GCT

  • Dermoid cyst / mature teratoma

Most Common Malignant GCT

  • Immature teratoma

Prognosis

  • Good prognosis
    • Due to detection at early age
  • Best prognosis:
    • Dysgerminoma
  • Worst prognosis:
    • Yolk sac tumor

Progression

  • Rapid progression:
    • Yolk sac tumor
      • Presents with acute abdomen

Radiosensitivity

  • Only radiosensitive ovarian tumor:
    • Dysgerminoma
    • Mnemonic: Germs are radiosensitive
    • notion image

Note on Radiosensitivity

  • Most radiosensitive organ: Ovaries
  • Ovarian CA are radioresistant

Teratoma/Dermoid Cyst

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Features

  • Most common benign ovarian tumor in women of reproductive age.
  • Found in reproductive age & pregnancy
  • During pregnancy, it’s the most common persistent (non-functional) ovarian tumor.
      • First trimester cyst → Corpus luteum cyst
      • Later persistent cyst → Dermoid cyst (most common benign tumor during pregnancy)
      • Most common complication → Torsion
      • Preferred time for elective surgery → Second trimester (16–20 weeks)
  • Mostly unilateral (U/L)
  • Bilateral (B/L) in 10%
  • Mostly benign

Types:

  • Mature Teratoma:
    • Benign.
  • Immature Teratoma:
    • Malignant (cancer in protuberance possible).

Monodermal Teratoma:

  • Contains only one type of tissue.
    • notion image
    • Struma Ovarii: 
      • Thyroid gland tissue in ovary.
        • Grossly:
          • Appears golden brown colored.
        • Microscopy:
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          • Shows areas with pink colloid.
        • Functional: Produces T3/T4, potentially causing hyperthyroidism.
  • A/w Totipotent stem cell
    • Stem Cell Type
      Potency
      Ability
      Function / Fate
      Totipotent
      Highest
      Differentiate into all cell types — embryonic and extraembryonic
      Can form a complete organism (e.g. zygote, 2-cell, 4-cell stage)
      Pluripotent
      High
      Differentiate into 3 germ layers: ectoderm, mesoderm, endoderm
      Form all embryonic tissues, but not extraembryonic tissues
      Multipotent
      Moderate
      Differentiate into multiple, but closely related cell types
      Give rise to a specific tissue lineage
      (e.g. hematopoietic → blood cells)
      Lineage Stem Cells
      Low
      Differentiate into specific lineages only
      Limited to a defined differentiation pathway

Grossly:

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  • Contains tissues from multiple germ layers (bone, skin, hair, teeth).
  • Most common component: Ectodermal tissue
  • Features a Rokitansky protuberance (solid area for cancer examination).

Malignancy

  • Risk: 0.2-2%
  • Common site of malignancy: Rokitansky protuberance
  • Common malignant type: Squamous Cell Carcinoma

USG Findings in Teratoma Ovary

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  • Tip of iceberg appearance
  • Dot & dash appearance
  • Rokitansky protuberance visualization

CT Scan of Pelvis Teratoma ovary

  • Mass with Calcification (white) + Fat (dirty black)
    • indicates a Teratoma/Dermoid.
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Management (mx)

  • Cystectomy recommended
    • Due to maximum risk of torsion
  • Oophorectomy performed
    • If family is complete

Dysgerminoma
(Seminoma in testes)

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  • Tumor markers: LDH, PLAP are increased.

Features

  • Usually unilateral (U/L)
  • GCT with highest risk of bilaterality:
    • 15-20% of cases
    • Mnemonic: Germs are both sides, germs are radiosensitive

Radiosensitivity

  • Only radiosensitive ovarian tumor:
    • Dysgerminoma
    • Mnemonic: Germs are radiosensitive
    • notion image

Grossly:

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  • Looks like a "cut potato".
    • Solid tumor
    • Fleshy consistency
    • Lobulated shape
    • Tan in color

Microscopy: 

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  • Nests of cells
    • Separated by fibrous septa
    • Lobules with Septa infiltrated by lymphocytes and plasma cells
  • "Fried egg appearance",
  • Mnemonic: Potato () um fried egg () um cut chyth vachapo → Germ (dysgerminoma) keri

Yolk Sac Tumor / Endodermal Sinus Tumor

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  • Commonly seen in children.
  • Tumor markers: Alpha-fetoprotein (AFP), Alpha 1 antitrypsin.

Features

  • Most malignant GCT
    • Note: m/c malignant GCT → Malignant Teratoma
    • Most rapidly progressing tumor
    • GCT with worst prognosis
  • Can present as acute abdomen
  • Always unilateral (100% U/L)

Histopathology (HPE)

Schiller Duval bodies
Schiller Duval bodies
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  • Schiller Duval bodies present
    • Similar to glomeruloid bodies
    • central blood vessel → two layers of tumor cells → space in between.
      • notion image

Choriocarcinoma

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  • Grossly: Appears hemorrhagic and necrotic.
  • Tumor marker: hCG (Human Chorionic Gonadotropin).
  • Microscopy: Two cell types:
    • Cytotrophoblast: Cells with one nucleus.
    • Syncytiotrophoblast: Cells with multiple nuclei (cluster).
  • Mnemonic:
    • Chori comes alone (Cyto) or in groups (synsitio)
    • Chori attack → full of blood

Sex Cord Stromal Tumors

Granulosa Cell Tumor

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  • Typically seen in postmenopausal patients.
  • Releases much estrogen → hyperestrogenism.
  • Presence: Any age.
  • Gene Defect: FoxL2 gene.
  • Estrogen Production:
    • Increased risk of endometrial carcinoma.
    • Requires endometrial biopsy.
  • Presentation:
    • Puberty: Puberty menorrhagia.
    • Reproductive/Perimenopausal Age: Abnormal Uterine Bleeding (AUB).
    • Menopausal: Postmenopausal bleeding.
  • Microscopy:
    • Coffee bean nuclei.
    • Call-Exner bodies (round bodies with pink material).
      • notion image
  • Tumor marker: Inhibin.
  • CD marker: CD99 positive.
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  • Granny story Mnemonic
      • Cystic BRAIN TUMORS
        • Craniopharyngioma
        • JPA
      Marker
      Positive In
      Mnemonic / Note
      Cytokeratin (CK)
      Carcinoma
      C for C
      Vimentin
      Sarcoma
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      CD45 / LCA
      Leucocyte Common Antigen
      Lymphoma
      L for L
      HMB45
      S 100
      Melanoma
      M for M
      CD1A
      Langerhans Cell Histiocytosis (LCH)
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      CD99
      Granulosa Cell Tumor (ovary)
      99-year-old granny
      (MIC2)
      Ewing Sarcoma (bone)
      Mitu → childhood tumor
      Glial Fibrillary Acidic Protein (GFAP)
      Tumor markers in glioma
      (Astrocytoma,
      Glioblastoma multiforme)
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      Lamin
      Progeria:
      Disorder of premature ageing
      (Hutchinson Gilford)
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      • Mnemonic:
        • Sarcoma
          • Vimal Sar
          • Also remember Rape (Rhabdomyosarcoma) Syn (Synovial) Mnemonic
        • Car
          • Sit (Cytokeratin) inside Car
          • Remember car → bike → took another route
            • Helmet (HCC → Fibrolamellar)
            • Rc book (RCC)
            • Phone (Follicular CA)
        • Granulosa cell tumor mnemonic
          • 99 year old granny ex ne vilikkan poi.
          • (99 (CD 99) year old granny → hyper estrogenism () → Called Ex (Call exner) → offered coffee (coffee bean) → she shouldve inhibited (inhibin) her)
        • Ewings sarcoma Mnemonic:
          • Mittu (MIC2) (11 year old) → Onion () kazhichapo wings () vannu → to Wings to Fly (EWS-FLI1) in Right (Homer wright) direction to get Pasta (Pas +ve).
          • Mittu thirichu vannapo 22 vayassai (t(11:22))
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      Condition
      Feature
      NF1
      Chromosome 17
      NF2
      Chromosome 22
      DermatoFIBROSARCOMA protrubans
      t (17;22)
      Nodular Fascitis
      t (22;17)
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Sertoli-Leydig Cell Tumor / Pure Leydig Cell Tumor

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  • Microscopy:
    • Presence of Reinke's crystalloids (characteristic of Leydig cells).
  • Mnemonic: Renga (Reinke) annante Lady (leidig)
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Fibroma

  • Associated with Meigs Syndrome:
    • Pelvis: Fibroma of ovaries.
    • Abdomen: Ascites.
    • Chest: Right-sided hydrothorax.
  • Associated with Gorlin Syndrome (for INIC aspirants): BBB Mnemonic
    • Bilateral fibromas (both ovaries).
    • Basal cell carcinoma (facial).
    • Blastoma (desmoplastic medulloblastoma in brain).
    • PTCH → Tumor Suppressor Gene
  • Gore Appearance for Halloween
    • Brain middle (Medulloblatoma) cut
    • Cut on face (BCC)
    • Fibre around neck (B/L Fibroma)

Krukenberg Tumor

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  • Type: Metastatic tumor of ovary.

CDH gene (E-cadherin):

  • Chromosome 16
  • "Glue" for cell-to-cell connection.

Loss/mutation

  • Mnemonic: Kadich (CDH) → Breastlum Vyarilum
  • "Golu" tumors/Kadicha tumors
      1. Diffuse Gastric Cancer
        1. Lauren's Classification
          Intestinal
          Lauren's Classification
          Diffuse
          Lauren's Classification
          Epidemiological
          Environmental
          Familial
          Pathology
          Gastric atrophy,
          intestinal metaplasia
          Blood Group A
          Sex
          m > F
          F > M
          Age
          ↑ Incidence with ↑Age
          Younger age
          Morphology
          Gland formation
          Round glands
          Poorly differentiated
          Cell Type
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          • Gross: Linitis plastica 
          ("leather bottle appearance").

          • Microscopy: Signet ring cells.
          Genetics
          APC gene mutations,
          Microsatellite instability
          p53, p16 inactivation
          Loss of E-cadherin
          (↓ E-cadherin)
          p53, p16 inactivation
          Invasion
          Hematogenous spread
          Transmural/Lymphatic spread
      1. Lobular Carcinoma Breast
          • Indian File/Single File Pattern
            • notion image
          • Mnemonic: File (Indian file) of Breast Ca patients
      1. Claudin low → EMT positive breast cancer

  • Krukenberg tumor
    • Stomach > Breast/ Colon
    • Signet Ring Cells
    • Retrograde lymphatic spread

NOTE: Miscellaneous one liners

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Intercalated Discs – Cardiac Muscle
Intercalated Discs – Cardiac Muscle
  • Most common primary source: 
    • Stomach CA (Pyloric end).
    • Also in breast and colon
  • Route of Spread: 
    • Retrograde lymphatics.
  • Bilateral Involvement: 
    • 80% cases.
  • Characteristics:
    • Symmetrical ovarian enlargement.
      • Shape retained.
    • Waxy.
    • Mobile.
    • Intact capsule.
  • On HPE: Signet ring cells.
    • Filled with mucin.
    • Nuclei pushed to periphery by large mucin vacuole.

Management of Ovarian Cancer

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Staging Laparotomy/Surgical Staging

  • Performed in all cases.
  • Steps:
      1. Ascitic fluid/peritoneal wash sample.
      1. Multiple peritoneal biopsies.
      1. Infracolic omentectomy (Not omental biopsy)
      1. Total Abdominal Hysterectomy (TAH) + Bilateral Salpingo-Oophorectomy (BSO).
      1. Pelvic & para-aortic lymph node dissection (LND).

Clinical Approach to Epithelial Ovarian Cancer

  • Investigation: CT scan to stage tumor.

Based on Tumor Stage:

  • Early Stage (1 or 2):
    • Staging laparotomy.
    • Post-operative/Adjuvant Chemotherapy (CT):
      • Carboplatin + Paclitaxel (6 cycles).
      • Add-on Drugs:
        • Bevacizumab (both BRCA positive/negative).
        • Olaparib (if BRCA positive).
          • Mnemonic: Olaparambu → Bra
    • Maintenance: PARP inhibitors (Olaparib, Niraparib) + Bevacizumab.
  • Advanced Stage (3 or 4):
    • Resectable Tumor:
      • Debulking/Cytoreductive surgery.
      • Adjuvant Chemotherapy (CT):
        • Carboplatin + Paclitaxel (6 cycles).
      • Maintenance:
        • PARP inhibitors + Bevacizumab.
    • Tumor Not Resectable:
      • Neoadjuvant Chemotherapy (3 cycles):
        • Carboplatin + Paclitaxel.
      • Re-assessment Post-Chemo:
        • If Resectable:
          • Debulking surgery.
          • Remaining 3 cycles of CT.
        • If Still Not Resectable:
          • Remaining 3 cycles of CT without surgery.
  • Mnemonic:
    • Car (Carboplatin) Park (Paclitaxel) cheythu → Ola (Olaparib) de mukalil Walk (Bevacizumab) cheythu
    • Sis Flu (5 FU) → Cervix
    • Sis (Cisplatin) Pack (Paclitaxel) → Uterus

Features of Non-Resectable Tumors:

  • Peritoneal caking.
  • Involves vital organs:
    • Stomach, liver, great vessels, intestine, mesentery.

Management of Germ Cell Tumors

  • Surgery: 
    • Unilateral salpingo-oophorectomy (typically for young females).
  • Chemotherapy:
    • Given for all stages.
    • Bleomycin, Etoposide, Cisplatin.
    • Exception: 
      • Dysgerminoma Stage I (may not need chemo).

Surveillance During Treatment (Platinum Free Interval)

↑↑ in CA 125 Levels while on surveillance:

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  • While on Platinum-Based CT:
    • Refractory to Drugs
      • DOC: Pegylated Liposomal Doxorubicin (PLD).
  • After Stopping CT:
    • Platinum free interval (PFI)
      • < 6 months.
        • Platinum Resistant Relapse
          • DOC: Paclitaxel, Bevacizumab.
      • > 6 months.
        • Platinum Sensitive Relapse
          • DOC: Carboplatin, Paclitaxel.
  • Note: Partial platinum resistance does not exist.

CASE 1

Functional Ovarian Cysts

  • Most common type of cyst
  • Occurs due to hormonal disturbances
  • Temporary, typically resolves spontaneously
    • Specific treatment is not usually required

Types of Functional Ovarian Cysts

  1. Follicular Cyst
      • Most Common
      • Size of follicle is ≥ 3 cm.
      • Presentation
        • Unilocular, Thin walled, Anechoeic cyst
        • Mobile tender cystic adnexal mass
        • Lower Abdominal pain
        • Reproductive age group
      • Recurrent Cyst
        • OCPs
  1. Corpus Luteum Cyst
      • Most common cyst to rupture.
        • Stage of Pregnancy
          Most Common Cyst Type
          First trimester
          Corpus luteum cyst
          Second & third trimester
          [Overall]
          Dermoid cyst
          (
          mature cystic teratoma)
  1. Theca Lutein Cyst
      • Occurs due to ↑↑ HCG levels.
      • Seen in:
        • Molar pregnancy
        • Twin pregnancy
        • Infertility treatment:
          • Clomiphene
          • HMG
  1. Hemorrhagic cyst
      • Reticular / Fish Net Pattern
  1. Endometrioma (Chocolate Cyst)
      • Thick walled
        • notion image
      • First investigation:
        • TVS (rules out other disorders)
          • Ground glass echogenicity
          • Homogenous Internal Echoes
          • Ground glass echogenicity
            Ground glass echogenicity
      • If patient desires pregnancy:
        • Do not treat (conservatively managed)
        • Pregnancy rates
          • 60% in moderate disease
          • 35% in severe disease
      • If patient does not desire pregnancy:
        • Asymptomatic and <5 cm:
          • Follow-up with USG
        • Asymptomatic and ≥5 cm or symptomatic cyst:
          • Laparoscopic cystectomy + HPE
  1. Malignant cyst
      • Solid cyst
      • Thick septae
      • Papillary excrescences
      • ↑ Vascularity in septae
  1. Abscess
      • Internal echoes
      • Heterogenous
      • ↑ Vascularity → ↑ Doppler flow
  1. Ovarian Torsion
      • Twisted pedicle
      • ↓ Vascularity
  1. Dermoid cyst
      • Shows calcification
      • Rokitansky Protuberance
  1. Serous cystadenoma
      • Unilocular

Ovarian Cysts Without Features of Malignancy on Ultrasound

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Important Notes

  • Malignant Transformation of Ovarian Masses:
    • 30% in postmenopausal.
    • 7% in premenopausal.
  • CA 125
    • Reproductive Age Group:
      • ≥ 200 IU: Significant (suggests malignancy).
    • Postmenopausal
      • ≥35 IU: Significant

Approach

  • Reproductive Age Group:
    • Size
      Action
      < 5 cm
      Watch
      5-7 cm
      Serial ultrasound monitoring
      > 7 cm
      Surgical excision if risk of torsion
  • Extremes of Age
    • Post-menopausal
      • Check CA 125,
    • Pre-pubertal
      • Suspect dysgerminoma
        • AFP, HCG, LDH levels.
      • If abnormal, consider malignancy.

CASE 2

Ovarian Cysts in Pregnancy

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  • Clinical Approach Based on Symptoms
    • Symptomatic Cyst:
      • Surgery irrespective of gestational age.
    • Asymptomatic Cyst:
      • 1st Trimester:
        • Wait & watch (mostly corpus luteal cyst).
      • 2nd/3rd Trimester:
        • Surgery if
          • malignant features OR
          • size ≥ 10 cm on ultrasound.

Important Notes

  • Most Common Benign Tumor: Dermoid cyst.
  • Most Common to Undergo Torsion: Dermoid cyst.
  • Most Common at End of 1st Trimester/During Puerperium: Dermoid cyst.
  • Most Common Ovarian Cancer in Pregnancy: Dysgerminoma.