Epidemiology of Squamous Cell Carcinoma of the Lip in the United States: A Population-Based Cohort Analysis.
Squamous cell carcinoma of the lip (lip SCC) composes more than 25% of all oral cancers. Most of the demographic and prognostic indicators for lip SCC are only available through retrospective case series.



To examine the incidence, treatment, overall survival, and disease-specific survival (DSS) of patients with lip SCC.



Population-based cohort analysis using the Surveillance, Epidemiology, and End Results database identified patients with lip SCC between January 1, 1973, and December 31, 2012.



Overall survival and DSS.



A total of 15 832 cases of lip SCC were identified. The cohort was composed of 12 945 men (81.8%) and 2887 women (18.2%). The mean age at diagnosis was 66.1 years. White patients accounted for 98.4% of the cases. Most of the tumors presented in the lower lip (77.8% external and 10.2% mucosal), whereas the external upper lip, mucosal upper lip, and the oral commissure represented 8%, 1%, and 1.2% of all cases, respectively. Of the patients, 91.2% underwent surgical therapy, 7.7% received radiation therapy, and 4.7% received both. Overall survival at 2 years, 5 years, and 10 years was 85.5%, 69.9%, and 50.2%, respectively. Multivariate analysis revealed that age, primary site, T stage, and N stage were determinants of overall survival and DSS. Kaplan-Meier survival analysis showed that SCC of the upper and lower lip had similar overall survival (163.6 months vs 163.8 months) and DSS (418.6 months vs 423.6 months). In contrast, SCC of the oral commissure had significantly lower overall survival (128.5 months) and DSS (286.7 months).



Our study demonstrates that lip SCC predominantly affects white men in their mid-60s. The determinants of survival for lip SCC include age at diagnosis, primary site, T stage, and N stage. Squamous cell carcinoma of the upper lip and lower lip had similar survival, whereas SCC of the oral commissure was associated with decreased survival.
Department of Head and Neck Surgery, David Geffen School of Medicine at University of California, Los Angeles.
Albert Y
AY
Han
Department of Head and Neck Surgery, David Geffen School of Medicine at University of California, Los Angeles.
Edward C
EC
Kuan
Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco Medical Center.
Jon
J
Mallen-St Clair
Department of Head and Neck Surgery, David Geffen School of Medicine at University of California, Los Angeles.
Jose E
JE
Alonso
Department of Orthopaedic Surgery, David Geffen School of Medicine at University of California, Los Angeles.
Armin
A
Arshi
Department of Head and Neck Surgery, David Geffen School of Medicine at University of California, Los Angeles4Jonsson Comprehensive Cancer Center, University of California, Los Angeles Medical Center5University of California, Los Angeles Head and Neck Cancer Program, University of California, Los Angeles Medical Center.
Maie A
MA
St John
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008048:Lip Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D018714:Radiotherapy, Adjuvant; D018426:SEER Program; D017678:Sex Distribution; D014481:United States / Q000453:epidemiology; D055815:Young Adult