Predictors of occult nodal metastasis in patients with thin melanoma.
OBJECTIVE
Thin primary lesions are largely responsible for the rapid increase in melanoma incidence, making identification of appropriate candidates for nodal staging in this group critically important. We hypothesized that common clinical variables may accurately estimate the risk of nodal metastasis after wide excision and determine the need for sentinel node biopsy.


METHODS
Review of prospectively acquired data in a large melanoma database.


METHODS
A tertiary referral center.


METHODS
A total of 2211 patients with thin melanoma treated by wide local excision alone were identified in the database between January 1, 1971, and December 31, 2005. Of those, 1732 met entry criteria.


METHODS
We examined the rate of regional nodal recurrence and the impact of clinical and demographic variables by univariate and multivariate analyses.


RESULTS
The overall nodal recurrence rate was 2.9%; median time to recurrence was 38.3 months. Univariate analysis of 1732 patients identified male sex (P < .001), increased Breslow thickness (P < .001), and increased Clark level (P < .001) as significant for nodal recurrence. Multivariate analysis identified male sex (hazard ratio, 3.5; 95% confidence interval, 1.8-7.0; P < .001), younger age (0.45; 0.24-0.86; P = .001), and increased Breslow thickness (2.5; 1.6-3.7; categorical P < .001) as significant for nodal recurrence. The Clark level was no longer significant (P = .63). Breslow thickness, age, and sex were used to develop a scoring system and nomogram for the risk of nodal involvement. Predictions ranged from 0.1% in the lowest-risk group to 17.4% in the highest-risk group.


CONCLUSIONS
Many patients with thin melanoma will have nodal recurrence after wide excision alone. Three simple clinical variables may be used to estimate recurrence risk and select patients for sentinel node biopsy.
John Wayne Cancer Institute, 2200 Santa Monica Blvd., Santa Monica, CA 90404, USA. fariesm@jwci.org
Mark B
MB
Faries
Leslie A
LA
Wanek
David
D
Elashoff
Byron E
BE
Wright
Donald L
DL
Morton
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D006801:Humans; D015994:Incidence; D008197:Lymph Node Excision; D008297:Male; D008545:Melanoma / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012878:Skin Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D016019:Survival Analysis; D055815:Young Adult