[1054] Atypical Tubal Metaplasia in Endometrial Samplings Is Not Associated with Increased Risk of Developing Hyperplasia or Carcinoma: A Long Term Follow-Up Study of 63 Cases

SL Peng, RA Simon, MR Quddus, C Zhang, WD Lawrence, CJ Sung. Brown University Alpert Medical School, Providence, RI; National Cheng Kung University, Tainan, Taiwan

Background: Tubal metaplasia (TM) of the endometrium, characterized by ciliated cells with round vesicular nuclei and eosinophilic cytoplasm, is a well-recognized benign entity, often seen with dysfunctional uterine bleeding (DUB). In some cases, ciliated epithelia may exhibit worrisome cytologic features (ATM) and present a diagnostic dilemma regarding its clinical significance. The aim of our study is to evaluate the natural history of ATM and the risk of subsequent endometrial hyperplasia and neoplasia through a long term follow-up.
Design: We identified 63 cases of ATM within benign endometrial samplings including: 30 poorly active endometria; 16 atrophic endometria, 2 weakly proliferative endometria, 3 disordered proliferative endometria, 8 proliferative endometria with breakdown, and 4 endometrial polyps. No concomitant hyperplasia or malignancy was present. The criteria for cytologic atypia included: variably-sized and shaped enlarged nuclei; smudgy hyperchromatism and prominent nucleoli; variable amounts of eosinophilic granular cytoplasm, often abundant; and cuboidal and hobnail configurations. Follow-up information was available in all 63 cases. The controls consisted of 200 cases of benign endometrium from patients with DUB and no cytologic atypia. Fisher Exact Test was utilized for statistical analysis.
Results: The median age was 56 years (range 24-84) for ATM patients versus 54 years (range 27-85) for the controls. After a median follow-up period of 46 months (range 0.5-88), the ATM group developed 3 cases of simple hyperplasia (SH), one complex atypical hyperplasia (CAH) and one endometrioid carcinoma, the latter diagnosed 88 months after the initial biopsy showing ATM. The control group was followed by 7 cases of hyperplasia (4 simple and 3 complex), 1 atypical SH and 3 CAH (median follow-up 91 months).

	Hyperplasia without atypia	Atypical hyperplasia/carcinoma
ATM (63)	3 (4.8%)	2 (3.2%)
Control (200)	7 (3.5%)	4 (2%)
	p=0.44	p=0.44

Conclusions: Our study suggests that the entity of ATM per se is not a direct precursor to atypical endometrial hyperplasia or endometrioid carcinoma and its presence in endometrial specimens does not portend a greater risk for patients to develop those lesions as compared to the control population. Recognition of ATM in endometrial samplings is important and may prevent unwarranted aggressive clinical management.
Category: Gynecologic

Wednesday, March 11, 2009 1:00 PM

Poster Session VI # 138, Wednesday Afternoon