Verification of a formula for determination of preexcision surgical margins from fixed-tissue melanoma specimens.
BACKGROUND
Recently our group reported on the shrinkage of 199 malignant melanoma surgical-excision specimens. In that report, a multivariate analysis revealed that the age of the patient was the only factor that significantly affected the percentage shrinkage of a surgical specimen. In addition, a formula was presented that extrapolates the actual surgical margins (in vivo) from the (contracted) fixed-tissue pathology report measurement and the reported in vivo lesion diameter.


OBJECTIVE
The goals of this study are to verify that shrinkage of surgical specimens is approximately 20% and that the margin formula can be successfully applied to a different group of patients.


METHODS
Four hundred seven patients with malignant melanoma were prospectively enrolled to measure preexcision (outlined with ink) surgical margins, fixed-tissue (contracted) surgical margins, and overall specimen shrinkage.


RESULTS
It is verified that overall shrinkage of cutaneous surgical specimens is approximately 20%. Surgical specimens from patients younger than 50 years of age have approximately 25% shrinkage. Those specimens from patients 50 to 59 years of age have approximately 20% shrinkage and those from patients 60 years of age or older have about 15% shrinkage. The surgical margins predicted by the margin formula were within +/- 3.5 mm of the actual measured surgical margin 86.5% of the time.


CONCLUSIONS
The actual surgical margins (in vivo) of a malignant melanoma can be reasonably estimated from the fixed-tissue pathology measurement via the margin formula. The shrinkage of a surgical specimen is 15% to 25% depending on the patient's age.
Silverman
M K
MK
Melanoma Cooperative Group, New York University Medical Center, New York.
Golomb
F M
FM
Kopf
A W
AW
Grin-Jorgensen
C M
CM
Vossaert
K A
KA
Doyle
J P
JP
Levenstein
M J
MJ
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D062109:Dermatologic Surgical Procedures; D006801:Humans; D008545:Melanoma / Q000473:pathology* / Q000601:surgery*; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012867:Skin / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology* / Q000601:surgery*; D016707:Tissue Fixation