Detection of microinvasion in vulvar and cervical intraepithelial neoplasia using double immunostaining for cytokeratin and basement membrane components.
BACKGROUND
Identification of early invasion in vulvar intraepithelial neoplasia 3 (VIN 3) and cervical intraepithelial neoplasia 3 (CIN 3) may be difficult with the use of routine hematoxylin-eosin staining. Presence of obscuring inflammation and tangential tissue sectioning are the most common diagnostic pitfalls.


OBJECTIVE
To examine the utility of double immunostaining for cytokeratin-collagen IV or cytokeratin-laminin in the detection of early invasion in VIN 3 and CIN 3.


METHODS
The study group consisted of 10 cases of "VIN 3, suspicious for invasion" and 10 cases of "CIN 3, suspicious for invasion." The negative control group consisted of VIN 3 (n = 15) and CIN 3 (n = 10). The positive control group consisted of cases of invasive vulvar carcinoma (n = 11) and invasive cervical carcinoma (n = 25). All cases were double immunostained for cytokeratin and collagen IV and, in a separate reaction, for cytokeratin and laminin. The continuity of the basement membrane and the presence of stromal invasion were assessed in the stained sections.


RESULTS
The staining for collagen IV and laminin yielded identical results. A well-defined, continuous basement membrane was visualized in all cases of VIN 3 and CIN 3. A discontinuous or absent basement membrane was observed around the malignant cells on the invasive tumor front in all cases of vulvar and cervical carcinoma. In 2 of 10 cases of VIN 3, suspicious for invasion and in 4 of 10 cases of CIN 3, suspicious for invasion definitive foci of microinvasion were identified with the use of double immunostaining. A well-defined, continuous basement membrane was present in the remaining cases "suspicious for invasion."


CONCLUSIONS
Double immunostaining for cytokeratin- collagen IV or cytokeratin-laminin is useful for evaluation of early invasion in equivocal cases of VIN 3 and CIN 3.
Rush
Demaretta
D
Department of Pathology and Laboratory Medicine, Malcolm Randall VA Medical Center, and University of Florida College of Medicine, Gainesville, USA.
Hyjek
Elizabeth
E
Baergen
Rebecca N
RN
Ellenson
Lora H
LH
Pirog
Edyta C
EC
D000230:Adenocarcinoma / Q000737:chemistry / Q000473:pathology; D001485:Basement Membrane / Q000737:chemistry / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis; D024141:Collagen Type IV / Q000032:analysis; D005260:Female; D006801:Humans; D007633:Keratins / Q000032:analysis*; D007797:Laminin / Q000032:analysis; D009361:Neoplasm Invasiveness; D012189:Retrospective Studies; D002583:Uterine Cervical Neoplasms / Q000737:chemistry / Q000473:pathology*; D014846:Vulvar Neoplasms / Q000737:chemistry / Q000473:pathology*; D002578:Uterine Cervical Dysplasia / Q000737:chemistry / Q000473:pathology*
D014408:Biomarkers, Tumor; D024141:Collagen Type IV; D007797:Laminin; D007633:Keratins