Presenting Author Information
Adela Cimic, MD
Columbia University Irving Medical Center
New York, NY 

Second Author Information
Simon Sung, MD
Columbia University Irving Medical Center
New York, NY

Disclosure:  We do not have any affiliations or financial interests in any of the corporate organizations involved with the products to which our case study will refer.

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Clinical History

43-year-old female, with no significant past medical history, presents to the physician’s office for the annual medical exam. A Pap smear is taken and the results for high-risk human papillomavirus testing (HR-HPV) are pending at this time. Based on the above images what is the most likely origin of these cells?

Educational Objective 1: The student should be able to identify abnormal cells in the Pap test.

Educational Objective 2: The student should be able to distinguish between dysplastic cervical cells and rare benign mimickers.

Educational Objective 3: The student should be able to give a preliminary diagnosis and seek.

Educational Objective 4: Recognize diagnostic pitfalls of this lesion additional history for the adequate interpretation.

Cytopathology Features

Hormonal stimulation in pregnancy can cause morphological changes (decidualization) in both cervical and endometrial stromal cells. Decidual cells can sometimes be present in the Pap test of pregnant or postpartum women. Their cytomorphologic features have been described as large polygonal cells that present singly and in clusters. In thin-layer preparations (ThinPrep), these cells are usually seen singly. They have smooth, round nuclear contours, sometimes with hyperchromasia, if degenerative changes are present. Also, they can have occasional prominent nucleoli. Decidual cells can have both low and high nuclear-to-cytoplasmic ratio (N/C ratio), but if they have cytoplasm, the cytoplasm is usually abundant basophilic or eosinophilic finely granular and peripherally vacuolated. Given the aforementioned features, the most helpful finding, besides the morphologic appearance, would be a positive pregnancy test. If HR-HPV is negative, interpretation of negative for intraepithelial lesion or malignancy should be rendered.

In this particular case, the review of medical records revealed elevated beta-hCG and unexpected pregnancy. Her HR-HPV test was negative.

Figure 1:  Single cells with oval, smooth nuclear contours and translucent cytoplasm.  (60x, ThinPrep Papanicolaou stain)

Figure 2:  A row of slightly hyperchromatic cells with dense and focally vacuolated cytoplasm. (20x, ThinPrep Papanicolaou stain)

Figure 3:  Cluster of cells with rare prominent nucleoli. (40x, ThinPrep Papanicolaou stain)