Australian Society of Cytology

Case of the Month

March 2003 - Answer and Discussion

Invasive endocervical adenocarcinoma

Discussion

This specimen was reported as benign by the primary screener, who noted the conventional smear was unsatisfactory while the ThinPrep specimen was satisfactory for assessment. The slide was referred for rescreening due to the abnormal clinical history. The rescreener queried abnormal glandular cells and referred the slides to the pathologist who reported the specimen as Inconclusive: Possible high-grade glandular abnormality.

Follow-up cone biopsy at another laboratory revealed an invasive endocervical adenocarcinoma. The patient underwent a total hysterectomy but unfortunately died as a result of operative complications.

The smear reported two years previously was found to be benign on review with no endocervical component present.

This case highlights the both the importance of rescreening smears from high risk patients, i.e. abnormal clinical history and the difficulty in diagnosing invasive endocervical adenocarcinoma on cytology.

On the conventional smear, cellular material was obscured by blood and inflammatory exudate and there were scanty squamous cells present. There were moderate numbers of glandular cells which were obscured by the blood, but on low power showed hyperchromasia and crowding. Some prominent nucleoli were noted. These groups were difficult to assess on high power due to the excessive blood and consequent poor fixation.

The ThinPrep slide was easier to assess. There was a significant reduction in contamination by blood and inflammation, although there was some background debris present. On review, this may be interpreted as diathesis, however, this is a diagnostically difficult area in ThinPrep specimens. The hyperchromatic crowded groups of glandular cells were better preserved and crowding of nuclei, hyperchromasia and prominent nucleoli were more easily recognised. There were some smaller groups of glandular cells noted also.

The difficulties in detection and diagnosis of invasive adenocarcinoma have been well documented. It is recognised that in the screening setting, a higher false negative rate for cervical adenocarcinoma than squamous cell carcinoma is to be expected (1).

In a recent study from Western Australia, Schoolland et al undertook a review of cervical smears from patients with histologically proven endocervical adenocarcinoma (2). Their review highlighted some useful criteria which may have been under-emphasised in standard text books that discuss features of endocervical adenocarcinoma. These include heavy bloodstaining with accompanying abundant glandular material and scanty squamous cells. Heavy bloodstaining may be a more useful marker than the presence of necrosis of tumor 'diathesis'. The authors also noted that since these specimens are often heavily contaminated by blood, they are often reported as unsatisfactory, when on review, abnormal material is present.

Glandular abnormalities have been reported as a difficult area in ThinPrep specimens (3). In this case the cells were more easily evaluated than on the conventional smear due to the reduction in blood and improved cellular preservation.

The incidence of endocervical adenocarcinoma is relatively low in most routine screening cytology laboratories and most cytologists and pathologists get little opportunity to gain experience in this area. This case has served to highlight some important clues in diagnosis:

Beware

Unsatisfactory due to blood
Scanty squamous cells
Abundant glandular epithelial cells

Rule out -

Invasive carcinoma