[508] Nevi with Epithelioid Cytomorphology and Architectural Disorder

Jennifer Kaplan, Steven R Tahan. Beth Israel Deaconess Medical Center, Boston

Background: Dysplastic nevi (dysN) were recognized over 30 years ago as melanocytic proliferations with distinctive architectural and cytologic features in families with relatively high incidence of melanoma. Numerous descriptions of dysN have been published; however nevi with epithelioid cytologic features and architectural disorder (NACED) have not been as well described.
Design: To further understand the clinical and histologic characteristics of NACED, we reviewed all 40 identified cases of NACED diagnosed at our institution from 1997 to 2010. Medical records were reviewed, and patients were separated into categories based on personal history of multiple dysN, personal history of malignant melanoma in situ and/or invasive melanoma, and family history of melanoma. Histologic sections were reviewed and 23 pathologic features were compared among the groups of patients.
Results: No single histologic feature statistically correlated with personal history of multiple dysN or melanoma, family history of melanoma, or lack of personal or family history. 89% of patients with a personal or family history of melanoma had lesions that were categorized to have overall high-grade morphology. Conversely, only 64% of patients without a personal or family history of melanoma had similar lesions (Table).

Histologic Features of Nevi with Epithelioid Cytomorphology and Architectural Disorder

Histologic Feature	All Patients (%)	No Personal or Family History of Melanoma (%)	Multiple DysN (%)	Personal History of MMIS or Melanoma (%)	Family History of Melanoma (%)	Personal or Family History of Melanoma (%)
Overall High Grade	75	64	64	86	100	89
High N/C Ratio	20	18	36	43	25	33
Large Nucleoli	55	41	55	71	50	67
Coarse Chromatin	38	41	46	43	50	33
Intraepidermal Mitoses	48	41	64	43	25	33
Kamino Bodies	35	36	46	29	50	33
Pagetoid Lateral Spread	50	41	18	14	25	22
Lack of Lateral Circumscription	68	67	73	86	50	78
Clefts Around Nests	25	23	9	29	0	22
Bridging of >3 Rete	18	82	82	14	50	67
Focal Atrophy	23	18	18	17	25	11
Dermal Mitoses	31	28	27	17	0	14
Lack of Dermal Maturation	80	22	18	71	0	14

Conclusions: In this largest series to date of NECAD, there was no correlation between a wide array of histologic features and personal or family history of melanoma. While high grade morphology was more frequent in patients with a personal or family history of melanoma, this could not be statistically validated with this small data set. These findings raise the possibility that these lesions may not have the same prognostic significance as traditional dysplastic nevi.
Category: Dermatopathology

Wednesday, March 21, 2012 1:00 PM

Poster Session VI # 125, Wednesday Afternoon