Congenital melanocytic nevi and DNA content. An analysis by flow and image cytometry.
BACKGROUND
Potential risk factors for the development of melanoma in congenital melanocytic nevi (CMN) are not well established. DNA aneuploidy may constitute such a risk factor but has not been sufficiently studied in CMN.


METHODS
In the present study, DNA analysis of eight giant CMN, nine medium CMN (1.5-20 cm), and eight small CMN (< 1.5 cm) was assessed by flow cytometry and selected lesions (six nevi) by DNA image cytometry. DNA content was correlated with patient age, nevus size, and degree of cytologic atypia.


RESULTS
DNA aneuploidy was detected by flow cytometry in two giant CMN from adult patients and in a small CMN from a child. DNA aneuploidy was not observed in any of the six CMN studied by image cytometry, although an increased S-phase was noted in a markedly atypical giant CMN. No DNA aneuploidy was detected in medium-sized CMN or in the CMN of nine patients 1 year of age or younger.


CONCLUSIONS
In contrast to previous studies, it was observed that abnormal DNA content does tend to correlate with cytologic atypia, particularly in giant CMN with atypia or melanoma, in adults. Conversely, frank DNA aneuploidy in any CMN in children younger than 1 year of age, irrespective of histologic findings, was not detected. Finally, based on these limited studies, greater sensitivity of image over flow cytometry for detection of DNA aneuploidy cannot be verified.
Department of Pathology, Brigham and Women's Hospital, Boston, MA 02114.
R L
RL
Barnhill
M
M
Aguiar
C
C
Cohen
S
S
Kang
J
J
Kennedy
B
B
Schmidt
A J
AJ
Sober
A R
AR
Solomon
D000293:Adolescent; D000328:Adult; D000368:Aged; D000782:Aneuploidy; D002467:Cell Nucleus / Q000648:ultrastructure; D002648:Child; D002675:Child, Preschool; D003094:Collagen; D003584:Cytological Techniques; D004273:DNA, Neoplasm / Q000032:analysis* / Q000235:genetics; D004171:Diploidy; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008544:Melanocytes / Q000473:pathology; D008545:Melanoma / Q000235:genetics / Q000473:pathology; D009508:Nevus, Pigmented / Q000151:congenital* / Q000235:genetics* / Q000473:pathology; D012307:Risk Factors; D012878:Skin Neoplasms / Q000151:congenital* / Q000235:genetics* / Q000473:pathology
D004273:DNA, Neoplasm; D003094:Collagen