You see a patient for routine cervical cancer screening, perform the pap smear (and even remember to implement a few clinical pearls about cervical cytology collection from a past SOAP Note), and order the correct cytology order. Everything is awesome, or so it seems. Then a week later you get the following in your in-basket: “Sample adequate for cytologic evaluation. Endocervical component absent.”
At first glance, “endocervical component absent” doesn’t exactly inspire confidence, owing to the traditional viewpoint that the ideal cervical cytology sample would contain ectocervical, endocervical and transformation zone (TZ) cells in adequate numbers to detect abnormalities. However, there are several reasons why the endocervical component may not be present: presence of BV or bacterial/fungal infection; increased age (associated with the TZ migrating higher in the endocervical canal and making sampling more difficult); current pregnancy or parity; or inappropriate use of a sampling device.
But wait! Multiple studies have shown that the absence of endocervical cells is not associated with a higher risk of cervical disease, and high-risk HPV testing appears to be independent of TZ sampling (see Mitchell 2001, Elumir-Tanner et al 2011, Huang et al 2009, and Zhao et al 2007, among others). Furthermore, this evidence has been incorporated into the American Society for Colposcopy and Cervical Pathology’s (ASCCP) 2019 guideline for abnormal cervical cancer screening tests:
- “For patients aged 21 to 29 years with negative screening cytology and absent endocervical cells/transformation zone component (i.e., endocervical cells or squamous metaplastic cells), routine screening is recommended (BIII). When cervical cytology alone is performed for screening, HPV testing as a triage test after negative cytology and absent endocervical cells/transformation zone component in this age group is unacceptable (DIII). For patients 30 years or older with Negative for Intraepithelial Lesion or Malignancy (NILM) cytology and absent endocervical cells/transformation zone component and no or unknown HPV test result, HPV testing is preferred (BIII).”
Thus, from a clinical utility standpoint, the absence of an endocervical component has little impact on how we interpret cytology results, assuming that we continue to follow guideline recommendations.