Ovarian Cancer Screening:

BiomarkersAmandeep K Anand, MD, FICOGConsultant GynecologistJ&K Health Services

Overview•Introduction•Epidemiology•Ovarian cancers•Biomarkers•Landmark trials•Biomarker panels•Conclusion

2

Introduction•Even though there are a lot of options in

treating gynecological malignancies, ovarian cancer still remains a leading cause of death.

•Diagnosis at an early stage is the most important determinant of survival.

•Current diagnostic options have limited success in early detection.

•Discovery of new diagnostic biomarkers/panels for early diagnosis of ovarian cancer is one of the main challenges of modern medicine.

Epidemiology…• Fourth most common cause of tumor-related

death in women. • Ovarian Ca accounts for nearly 4% of all Ca

among women.• Malignant epithelial ovarian Ca account for 90%

of all malignancies of the ovary• The overall lifetime risk of developing ovarian Ca

for women in the US is 1.4% to 1.8%. ▫ Varies from 0.6% for women with no family history, at

least three term pregnancies, and four or more years of oral contraceptive use, to 3.4% for nulliparous women with no oral contraceptive use.

▫ For women with a family history, the lifetime risk is estimated at 9.4%.

Epidemiology• Worldwide highest rates: Northern and Western

Europe, notably Scandinavia, and in North America.

• In India, cancer of the ovary is one of the most common cancers in females and occupied third/fourth rank among cancers occurring in women during the year 2004-05 in various Indian registries.

• Ovarian cancers have shown a steady increase from 1968 to 2005

Ovarian cancers•“Silent Killers”•Lack of symptoms in early stages of

disease•75% of cases are diagnosed in late stage

(stage III/IV)•90% cure rate in stage I/IIa•Five year survival rate with late stage

disease is <20% compared to upto 90% with early stage disease.

•Early detection is therefore critical for curative Rx interventions.

Biomarker• A substance secreted by tumor tissues

and not by normal tissues or tumor specific immune marker easily detectable in a body fluid.

• Ideally, a biomarker must be : – Sufficiently non-invasive– Inexpensive to allow wide spread

availability– Given the prevalence of ovarian Ca must

have high sensitivity for early stage disease (>75%) and extremely high specificity (99.6%) to attain a PPV of at least 10%.

• Ideal biomarker is not yet available

Potential biomarkers for ovarian cancer diagnosis

Types of markers Strategies or technologies Markers (Reference)

Gene-based ovarian cancer biomarkers

Inherited gene mutations

Mutations BRCA1 and BRCA2, hMLH1 and hMSH2

Epigenetic changes Hypermethylation BRCA1, RASSF1A, APC, p14ARF, p16INK4a, DAPKinase

Gene expression

Microarray technology Gene expression profiling

SAGE technology CLDN3, HE4, FOLR1, COL18A1, CCND1, FLJ12988

Protein-based ovarian cancer biomarkers

Proteomic technologies(Mass spectrometry)

Proteomic pattern analysisIdentification of single, novel biomarkers, such as cleavage fragment of inter-alpha-trypsin inhibitor heavy chain H4, transferrin, Afamin

MicroRNA-based ovarian cancer biomarkers

Microarray miRNA expression profiles: over-expressed miRNA, such as miR-200a and, miR-200b and, miR-200c and , miR-141 and, miR-21, miR-203, miR-205, and miR-214; Down-modulated miRNAs, such as miR-199a, miR-140, miR-145, and miR-125b1

Real-time PCR Up-regulated miRNA, such as miR-21, miR-92, miR-9, miR-126, and miR-29a; down-regulated miRNA, such as miR-155, miR-127, and miR-99b

Metabolite-based ovarian cancer biomarkers

NMR spectroscopy Metabolomic profile

Mass spectrometry Metabolic profiling

EDRN “Top Ten” Biomarkers for Detection of Ovarian Ca1. CA1252. HE43. CA 15-34. CA 72-45. B7-H4 (Ov-110)6. Transthyretin7. IGFBP-28. SMRP (Mesomark™)9. HK610.Cytokeratin 19 (CYFRA 21-1)

http://edrn.nci.nih.gov/

Cancer Antigen 125 (CA125)• Bast and colleagues (1981) • A 200 kd glycoprotein• “Gold Standard”• Elevated in the pre-clinical asymptomatic

phase of the disease (3 months)• Elevated in 50% of Stage I disease and

80% of epithelial ovarian cancers• Specificity is improved by addition of TVS • Numerous studies have confirmed the

usefulness of CA125 levels in monitoring the progress of patients with epithelial ovarian cancer.

CA125• Reference range: <35 U/mL• Disease recurrence: Doubling of this level

▫In patients with normalization of this marker after primary treatment

▫From the lowest levels in patients with an elevated serum marker value that never normalizes after primary treatment.

• Limitations:▫ Elevates also in benign gynecological disease▫ Low sensitivity in Stage I ovarian Ca▫ Annual CA125 alone lacks sufficient specificity in

the avg. risk population in post menopausal women.

Prostate, Lung, Colorectal and Ovarian (PLCO) Trial• Aim: To evaluate the effect of screening for ovarian cancer on

mortality• Methods: Randomized controlled trial of 78,216 women aged 55 to

74 years assigned to undergo either annual screening or usual care at 10 screening centers across the United States between November 1993 and July 2001. 

• Outcome measures: ▫ Primary: Mortality from ovarian Ca, including primary peritoneal and

fallopian tube cancers. ▫ Secondary: Ovarian Ca incidence and complications associated with

screening examinations and diagnostic procedures. • Conclusion:

▫ Among women in the general US population, simultaneous screening with CA125 and TVS compared with usual care did not reduce ovarian cancer mortality.

▫ Diagnostic evaluation following a false-positive screening test result was associated with complications

▫ However, compliance with screening was high in the intervention group.

JAMA. 2011 Jun 8;305(22):2295-303. doi: 10.1001/jama.2011.766.

UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS)

UKCTOCS Trial • Aim: Whether screening can save lives?• Methods: 202,638, postmenopausal women aged

50 and above were recruited through thirteen centres in England, Wales and Northern Ireland between 2001 and 2005. ▫Randomly assigned to two groups – control group

who received no screening (to reflect the current situation in the UK) and screen group who had annual screeningusing two tests: CA125 for those in the multimodal group A mathematical formula called the Risk of Ovarian

Cancer algorithm (ROCA) which assigned risk depending on the CA125 level. 

Regular

CA125 Test

Risk of Ovarian Cancer Calculation

based on longitudinal CA125 values (ROCC)

Normal

ROCC < low

Intermediate

low < ROCC < high

Elevated

ROCC > high

Repeat CA125

In 3 months Ultrasound

+ CA125

Maximum of 3 intermediate results per

year

Skates JCO 2003

ROCA: Risk of Ovarian Cancer Algorithm

UKCTOCS Trial •If an abnormality was seen, the scan was

repeated. In both groups women had more extensive testing with referral for surgery if there was persistent abnormality.

•The preliminary results show that screening has encouraging sensitivity for picking up ovarian cancer. 

•In late 2015, the main outcome (did less women die from ovarian cancer in the screen when compared to control group) will be analysed.

Human Epididymis Protein 4 (HE4)• Over expressed in 93% of serous, 100% of

endometrioid, and 50% of clear cell ovarian carcinomas.

• Elevated in more than half of the ovarian cancer patients who did not have elevated CA125 levels; therefore, the combination of markers provided slightly improved ovarian cancer diagnostic sensitivity.

• Higher sensitivity when comparing ovarian Ca to gynecological disease.

• FDA approved for monitoring disease recurrence/progression but NOT for screening

HE4•Certain histological types of ovarian cancer

(mucinous or germ cell tumors) rarely express HE4, therefore not recommended for monitoring of patients with these types of ovarian cancer.

•Reference value: Females: <140 pmol/L•Interpretation:

▫Increase HE4 suggests recurrence or disease progression, while a decrease suggests therapeutic response.

▫A change in serum HE4 concentration of >20% is considered significant.

Biomarker panels•CA125 + HE4 + CEA + VCAM-1

▫Sensitivity-86%▫Specificity-98%

•CA125 + Mesothelin + HE4▫Begins to increase 3 years before diagnosis

•CA-125 + leptin + prolactin + osteopontin + insulin-like growth factor II (IGF-II) + macrophage inhibitory factor (MIF)▫Sensitivity-95.3%▫Specificity-99.4% 

Conclusion• Development in genomics and proteomics, have shown a number of

promising biomarkers and also provided new insights into ovarian cancer diagnosis, but few have turned out to be useful in clinic.

• It still remains unclear, whether a single biomarker, a panel of biomarkers, or multiplexed information will yield the most accurate approaches to ovarian cancer detection.

• At present, the research on ovarian cancer biomarkers is still under way in three main aspects: ▫ One is further validation and the ongoing clinical trials of available or

potential biomarkers. ▫ Another is investigation of novel more specific and sensitive ovarian cancer

biomarkers. ▫ The third is development of multiple biomarkers for generating panels to

maximize the sensitivity and specificity of detection. • In the future, through effective integration of various more advanced

technologies and help of bioinformatics, more useful biomarkers for ovarian cancer diagnosis are likely to emerge.

• Furthermore, sharing of information among the scientific community will quicken the pace in the field of biomarker research from different angles.