Treatment of Squamous Metaplasia in Pap Smear
Squamous metaplasia alone requires no treatment—it is a normal physiological process and should be managed with routine age-appropriate cervical cancer screening only.
Understanding Squamous Metaplasia
Squamous metaplasia is a benign, normal transformation of columnar epithelium to squamous epithelium at the cervical transformation zone. This is not an abnormal finding requiring intervention 1.
The key distinction is that squamous metaplasia is fundamentally different from the abnormal cytology categories that require management:
- ASC-US (atypical squamous cells of undetermined significance)
- LSIL (low-grade squamous intraepithelial lesion)
- ASC-H (atypical squamous cells—cannot exclude HSIL)
- HSIL (high-grade squamous intraepithelial lesion)
- Invasive carcinoma 1
Management Algorithm for a 29-Year-Old Woman
For a 29-year-old woman with squamous metaplasia only on Pap smear:
- Continue routine screening with cervical cytology every 3 years 1
- Do not perform colposcopy 1
- Do not perform HPV testing (cotesting is not recommended for women aged 21-29 years) 1
- Reassure the patient that this is a normal finding
Important Clinical Pitfall
The critical error to avoid is confusing squamous metaplasia with dysplasia or squamous intraepithelial lesions. Recent research demonstrates that even when p16-positive squamous metaplasia is identified histologically (which may indicate transcriptionally active HPV), this represents early or morphologically non-evident SIL requiring close follow-up—but this is a histologic finding, not a cytologic diagnosis of "squamous metaplasia" 2.
If the Pap smear report states only "squamous metaplasia" without any qualifiers suggesting atypia or dysplasia, this represents normal cervical remodeling and requires no intervention beyond routine screening 1.
When to Deviate from Routine Screening
Only consider more frequent screening or immediate colposcopy if:
- The patient is immunocompromised (HIV infection) 1
- History of in utero diethylstilbestrol exposure 1
- History of previous cervical cancer 1
- The Pap smear shows any cytologic abnormality beyond benign squamous metaplasia 1
For this 29-year-old woman with isolated squamous metaplasia and no high-risk factors, the next Pap smear should occur in 3 years 1.