Management of Endocervical and/or Squamous Metaplastic Cells on Pap Smear
The presence of endocervical and/or squamous metaplastic cells on a Pap smear indicates adequate sampling of the transformation zone and requires no additional management beyond routine screening if the cytology is otherwise negative for intraepithelial lesion or malignancy.
When endocervical and/or squamous metaplastic cells are present with negative cytology, the specimen is considered satisfactory and the patient should return to routine age-appropriate screening intervals. 1
Understanding Specimen Adequacy
The presence of endocervical cells and/or squamous metaplastic cells serves as a quality indicator that the transformation zone—where most cervical cancers originate—has been adequately sampled. 1, 2
Key points about specimen adequacy:
- A satisfactory Pap smear should describe the presence or absence of the endocervical/transformation zone component in the adequacy statement 1
- The transformation zone contains both endocervical columnar cells and squamous metaplastic cells, which are immature squamous cells replacing columnar epithelium 2, 3
- Approximately 91-96% of properly collected cervical samples will contain these cellular components 3
Clinical Significance of These Cells
The presence of endocervical and/or metaplastic cells alone has no pathologic significance—it simply confirms adequate sampling. 2 However, certain metaplastic changes warrant closer attention:
- Intestinal metaplasia is strongly associated with both glandular and squamous neoplasias (p = 0.0002) and requires close follow-up even if no lesion is initially identified 4
- Ciliated cell (tubal) metaplasia shows weaker association with cervical abnormalities (p < 0.04), with over one-third of cases having no associated pathology 4
- Benign-appearing glandular cells after hysterectomy (from accessory ducts, adenosis, or fallopian tube prolapse) have no clinical significance 1
Management Algorithm
For negative cytology with endocervical/metaplastic cells present:
- Return to routine screening based on age and risk factors 1
- No additional testing or earlier repeat is needed 1
For absent endocervical/metaplastic cells with negative cytology:
- The specimen may still be satisfactory if other quality indicators are met 1
- Consider repeat sampling if clinical suspicion exists, though absence of these cells does not automatically indicate inadequate sampling 5
Common Pitfalls to Avoid
Do not assume that presence of endocervical/metaplastic cells guarantees detection of all abnormalities. Studies show that 25-30% of carcinoma in situ or dysplasia cases and 75% of invasive carcinoma cases may lack endocervical or metaplastic cells on cytology. 5 Conversely, 50% of false-negative smears contained these cell types despite missing dysplastic cells. 5
Do not confuse the presence of these normal cellular components with atypical glandular cells (AGC). If AGC is reported instead, immediate colposcopy with endocervical sampling is required for all patients, plus endometrial sampling for women ≥35 years or those with risk factors. 1, 6
For women ≥40 years with benign-appearing endometrial cells noted on cytology: Endometrial sampling is recommended even though this represents a separate finding from endocervical/metaplastic cells, as 0.5-1.8% of such specimens are associated with significant endometrial pathology. 1