Clinical guidelines for the treatment of melanoma are based largely on the behavior of thicker tumors. As a result, little is known about survival differences among patients with thinner tumors.
To investigate the variability in survival for American Joint Committee on Cancer stage T1 thin melanoma tumors, defined as tumors less than 1 mm thick at diagnosis.
This population-based series included 43,008 non-Hispanic whites in whom cutaneous melanoma was diagnosed between 2004 and 2013 from the California Cancer Registry. Survival outcomes were estimated using the Kaplan-Meier method. Cox proportional hazard models were used to estimate risk of death.
Survival for patients with thin ulcerated tumors was comparable to that for patients with stage II tumors, who are currently treated more aggressively. At 12 months, patients with thin ulcerated tumors had approximately 6% lower survival (92.5% [95% confidence interval (CI), 90.6%-93.9%]) compared with patients with thin nonulcerated tumors (98.2% [95% CI, 98.0%-98.3%]). At 24 months, this survival difference increased (85.2% [95% CI, 82.8%-87.4%] vs 96.1% [95% CI, 95.8-96.3%] for those with thin ulcerated and thin nonulcerated tumors, respectively) and a greater than 15% survival difference was seen at 60 months.
Previous reports of cancer registry data have noted some evidence of miscoding of thin tumors.
The poorer survival in patients with ulcerated tumors less than 1 mm thick implies the need for additional studies to determine potential benefits of more aggressive treatment.Le texte complet de cet article est disponible en PDF.
Key words : melanoma, staging, survival, tumor thickness
Abbreviations used : CI, SEER, SES, SLN, SLNB
| Funding sources: Supported by grant R01CA158407 from the National Cancer Institute and the National Institute of Child Health and Human Development. The collection of cancer incidence data used in this study was supported by the California Department of Public Health pursuant to California Health and Safety Code Section 103885; the Centers for Disease Control and Prevention's National Program of Cancer Registries, under cooperative agreement 5NU58DP003862-04/DP003862; and the National Cancer Institute's Surveillance, Epidemiology and End Results Program under contract HHSN2 61201000140C awarded to the Cancer Prevention Institute of California, contract HHSN261201000035C awarded to the University of Southern California, and contract HHSN261201000034C awarded to the Public Health Institute. Supported in part by the Population Health Shared Resource of the University of Colorado Cancer Center (P30CA046934).
| Conflicts of interest: None disclosed.
| The ideas and opinions expressed herein are those of the author(s) and do not necessarily reflect the opinions of the State of California, Department of Public Health, the National Cancer Institute, and the Centers for Disease Control and Prevention or their contractors and subcontractors.
| Reprints not available from the authors.