On colposcopy, a lesion is described using the 2011 IFCC classification. The squamocolumnar junction cannot be fully visualised because it lies partly within the endocervical canal. This corresponds to which transformation zone type?

• A Type 1
• B Type 2
• C Type 4
• D Type 3 ✓

Explanation

In the IFCC classification, a type 1 transformation zone is completely ectocervical, type 2 has partial extension into the canal but remains fully visible, and type 3 extends beyond the visible limits of the external os so the upper margin of the SCJ cannot be assessed. Type 3 TZ implies an incomplete colposcopic examination and favours excisional treatment so that occult canal disease is removed rather than missed.

Reference: Berek and Novak's Gynecology, 16th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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