The Accuracy of Diagnostic Colposcopy

Using ISCCP 2011 Classification

SUJOY DASGUPTA, Senior Resident,

Department of Gynecological Oncology,Chittaranjan National Cancer Institute(CNCI), Kolkata

General Assessment •Adequate/ inadequate for the reason•Squamo-columnar Junction visibility•Transformation zone types 1,2,3

Normal Colposcopic Findings

Original squamous epithelium:

Columnar epithelium

Metaplastic squamous epithelium

Deciduosis in pregnancy

Abnormal findings

General Principles

•Location of the lesion:

•Size of the lesion:

Grade 1 (Minor)

Thin aceto-white epithelium Fine mosaic, Fine punctation

Grade 2 (Major)

Dense aceto-white epithelium, Rapid acetowhitening

Coarse mosaic, Coarse punctuation

Nonspecific Leukoplakia, Erosion, Lugol’s staining

Suspicious for invasion Atypical vessels; Additional signs

Miscellaneous findings CTZ, Condyloma, Polyp, Inflammation

Stenosis, Congenital anomaly, Post treatment, Endometriosis

International Federation of Cervical Pathology & Colposcopy 2011

To determine the ability of the colposcopists to correctly identify the various categories of cervical neoplasia using IFCPC, 2011 terminology

To determine the accurarcy of coposcopy in non-cytology based screening programme

STUDY DESIGN

Prospective Study

STUDY POPULATION

Subjects participating in a community-based cervical cancer screening demonstration project

Approved by CNCI Human Research Ethics Committee

Inclusion Criteria

• Non-pregnant women

• Age 30-60 years

• Intact uterus

• Without past history of cervical precancer/ cancer

STUDY METHODOLOGY

Written Informed Consent from all the participants

Examination by trained health workers

Cervical specimen collection for Hybrid Capture 2 (HC2)

(HPV DNA of 13 high-risk types)

VIA (Visual Inspection with Acetic Acid)

STUDY METHODOLOGY (Contd.)

VIA Positive women

Colposcopy in the

same sitting

Every 10th VIA negative

Woman

HC2 positive women

(not having colposcopy in the field)

Recalled for colposcopy

IFCPC 2011 terminology for documentation

Colposcopy in the

same sitting

STUDY METHODOLOGY (Contd.)

Punch Biopsies In case of colposcopic findings of - Grade 1 or worse abnormalities - Miscellaneous findings From the worst affected areas - close to the squamo-

columnar junction (SCJ) Multiple biopsies- if the lesion extends to

>2 quadrants For HC2 +ve women with NORMAL colposcopy

- punch biopsy taken from anterior lip

STUDY METHODOLOGY (Contd.)

Colposcopic impressions were compared with the histological diagnosis as gold standard

Strength of agreement was measured using the weighted kappa statistics

Histology Colposcopy

Grade 1 Grade 2 Invasive

L-SIL Perfect agreement

H-SIL Perfect agreement

Invasive Perfect agreement

DEMOGRAPHIC VARIABLESof Screened Women

(n = 30773)

• Mean age (years) 38.7 + 8.1

• Mean age at marriage (years) 17.6 + 3.4

• Median number of pregnancies 3• Menopausal status Pre-menopausal 79.8% Post-menopausal 20.2%

SELECTION OF STUDY CASES

Total women screened 30773

Colposcopy done

Screen positive 3178

5556

Screen negative2378

Biopsy done2511

Inconclusive biopsy 45

Both colposcopy and satisfactory biopsy report

FINAL ANALYSIS

2466

AGREEMENT • Exact agreement between colposcopy and histology-

40.3% (993/2466)

* Weighted kappa <0.6 - poor agreement

>0.6 - good agreement

1.0 - excellent agreement

Weighted kappa* Impression

Overall (n= 2466) 0.17 Poor

VIA +ve (n = 1763) 0.12 Poor

HC2 +ve (n = 620) 0.35 'Fair'

Agreement in classifying cervical biopsy sample

AGRREEMENT (Contd.)

Colpo Diag

Histo Diagnosis

Normal Misc L-SIL H-SIL Inv Total

Normal175 (35.8%)

130 157 25 1 488

Misc 2225 (32.4%)

24 5 1 77

Grade 1 420 403688 (43.3%)

72 4 1587

Grade 2 35 41 10875 (28%)

8 267

Inv 2 3 5 730 (63.8%) 47

Total 654 602 982 184 44 2466

TEST PERFORMANCE OF COLPOSCOPY In Detecting H-SIL or Worse Lesions

Performance of Colposcopy

Sensitivity SpecificityPositive Predictive Value (PPV)

Negative Predictive Value (NPV)

Overall 84.8% 66.1% 10.3% 98.9%

VIA +ve women

94.6% 23% 8.7% 98.2%

HC2 +ve women 78.8% 76.7% 39.4% 94.9%

Adjusting for verification bias (IFCPC grade 1 as the threshold for referral)

DISCUSSION

Almost all the earlier studies - conducted in colposcopy clinics where women were referred for abnormal cytology (Pap smear)

Advantages of those studies-• Prior knowledge of cytological abnormalities can

influence colposcopic diagnosis

• Cytology is more specific than VIA and HC2, so less chance of False Positive Colposcopy & Histology

SALIENT FINDINGS

• Observed sensitivity to detect H-SIL+ is ≈90%, comparable to the that found in a meta-analysis of 8 longitudinal studies (60-97%)

• Colposcopy overestimates the severity of premalignant lesions, as seen in other studies

• Performs better in differentiating high grade from low grade lesions, rather than in differentiating low grade lesions from normal

• 25 HSIL cases did not have any colposcopic abnormality – suggesting ‘THIN CIN’

Accuracy of colposcopy is acceptable in non-cytology based screening using the IFCPC 2011 terminology

THANK YOU

ACKNOWLEDGEMENT

Dr Partha Basu

Dr Ranajit Mandal

Dr Pradip Das

Dr Dipanwita Banerjee

Dr Priyanka Singh

All the health workers of CPCI Project, CNCI