[1262] Architectural vs. Nuclear Atypia Defined FIGO Grade 2 Endometrial Endometrioid Adenocarcinoma (EEC): A Clinicopathologic Comparison of 154 Cases

Whitney Winham, Douglas Lin, Pam Stone, Marisa Nucci, Matt Quick. UAMS, Little Rock, AR; Brigham and Women's Hospital, Boston, MA

Background: FIGO grade 2 EEC carries a 88% five year survival rate. They are defined by >5% but <50% solid epithelial component. A small subset may display <5% solid growth, but display marked nuclear atypia and are therefore designated grade 2. We compared tumor characteristics, staging, and clinical outcome of patients with architectural versus atypia defined grade 2 EEC.
Design: 154 cases of grade 2 EEC were reviewed to confirm grade; percent solid growth, and presence/absence of atypia. Only marked atypia (characterized by significant nuclear pleomorphism identifiable at low power magnification or a pattern of enlarged nuclei, 1.5-2 x normal, with irregular nuclear contours, dispersed chromatin and prominently enlarged nucleoli) increased the FIGO grade one level. Depth of invasion, tumor stage, lymph node status and clinical outcomes were then compared.
Results: 154 cases were evaluated. 23 were eliminated based on review (6 to grade 3, 17 to grade 1). Of the remaining 131 FIGO II cases, 19 (15%) were grade 2 based on the presence of severe atypia and 112 (85%) met the architecturally defined criteria (Tables 1 & 2).

Pathologic features of architecturally and atypia defined tumors

	Invasive	<50% Invasive	>50% Invasive	Cervix +	Nodes +	Recurrance
Atypia Defined	17 (89%)	10 (53%)	7 (37%)	2 (11%)	2 (11%)	1 (5%)
Architecturally Defined	89 (79%)	63 (56%)	26 (23%)	3 (12%)	5 (4%)	8 (7%)

Recurrent cases - Clinicopathologic Features

Atypia	% Solid	Depth (%)	LVI \ LN	Stage	Recur site \ Time (months)	Adjuvant	Status
Severe	0	55	- \ 0	IB	Vaginal Cuff \ 6	No	NED
NS	5	0	- \ 0	IB	Unknown \ 10	No	NED
NS	30	25	+ \+	1A	Lung \ 16	+	LFU
NS	5	40	+ \ 0	1A	Lung, LN\ 27	+	DOD
NS	5	90	+ \ 0	1B	Unknown \ 46	+	LFU
NS	10	20	- \0	2	Port Site \ 24	+	NED
NS	10	50	+ \ 0	3	Lung \ 7	+	LFU
NS	40	100	+ \ 0	2	Unknown \ 12	+	AWD
NS	5	>90	0 \ 0	4	Lung \ 1	+	LFU

LVI-Lymph Vascular Invasion, LN-Lymph Node (0= not available), NS-Not severe, NED-No Evidence of Disease, LFU-Lost to Follow Up, DOD-Died of Disease, AWD-Alive with Disease


Conclusions: Atypia defined vs. architecturally defined grade 2 ECC's show no significant difference in stage and prognosis. An increase in grade based on presence of nuclear atypia stratifies patients at increased risk since 89% of these patients have myoinvasion at the time of hysterectomy which is in distinct contrast to our previous study (Mod Path 24 (1), 2011; 264A, Abstract 1119) where 70% of Grade I cases were non-invasive. No significant correlation between percentage of solid component and risk of recurrence was identified in this study.
Category: Gynecologic & Obstetrics

Tuesday, March 20, 2012 9:30 AM

Poster Session III # 174, Tuesday Morning