- Thin (≤1.0 mm) nodular melanoma (NM) has distinct clinicopathological features and outcomes compared with thin superficial spreading melanoma (SSM).
Why this matters
- There are limited data on patients with thin NM and their prognoses.
- Thin NMs were more likely to have head/neck location (OR, 2.16; 95% CI, 1.27-3.69), mitoses (OR, 1.97; 95% CI, 1.33-2.93), and regional metastasis (OR, 1.77; 95% CI, 1.02-3.05) compared with SSMs.
- Thin NMs were less likely to have regression (OR, 0.46; 95% CI, 0.29-0.72) or nevus remnants (OR, 0.60; 95% CI, 0.42-0.85) compared with thin SSMs.
- Patients with thin NM had higher risk for melanoma-specific death compared with patients with thin SSM (HR, 2.10 [95% CI, 1.24-3.56] vs HR, 2.20 [95% CI, 1.28-3.78] after adjustment for center heterogeneity).
- After stratification for tumor spread, there was no increased risk for melanoma-specific death for NM vs SSM among each stratum for localized melanomas (OR, 1.08; 95% CI, 0.89-1.30) or cases with regional metastasis (OR, 1.11; 95% CI, 0.94-1.32).
- 5062 patients with NM and 15,070 patients with SSM were analyzed for clinicopathological features and outcomes.
- Funding: Institute of Dermatologic Research Education; funding of individual authors is listed in the manuscript.
- Retrospective study.
- No central pathology review.