Trend Analysis of Cutaneous Squamous Cell Carcinoma of the External Lip From 1975 to 2016

Abstract

utaneous squamous cell carcinoma (cSCC) is the second most common nonmelanoma skin cancer, with an incidence between 5 and 96 per 100 000 individuals. 1,2 Most patients with this malignant neoplasm are diagnosed early and treated surgically with disease-free survival. However, between 3.7% and 5.8% of cases metastasize, leading to 4000 to 9000 deaths annually in the United States. 3 Cutaneous SCC of the head and neck (cHNSCC) is a primary site of special concern. Commonly affected sites in this region are the external lip and ear. Cutaneous HNSCC accounts for up to 49% to 60% of all cSCC cases, and the anatomical structures of this region predispose to high morbidity with invasive tumors. [4][5][6][7] Analyses of cSCC have found a strong correlation between UV radiation and immunosuppression with disease incidence. 2,5,8,9 These risk factors contribute to the varying in-cidence found within populations, with patients exposed to immunosuppressive drugs or higher UV index more likely to develop this malignant neoplasm. As such, geography is an important risk factor for patients. Individuals living in the more southern regions of the United States have traditionally been targeted as an at-risk group.Localized cases of cSCC are treated surgically, with minimum margins of 4.0 mm (T1) or 6.0 mm (T2) and are curative in 95% of cases. 6 Locally advanced tumors, T3 or greater, are at least 4 cm in size or invade bone or perineural structures. 2 These malignant neoplasms are almost always treated surgically, with either standard excision or Mohs micrographic surgery. Perineural invasion occurs in 2% to 14% of cases, with a high risk of recurrence (47%) and metastasis (35%). 10 Treatment of metastatic disease is multidisciplinary; lymphadenec-IMPORTANCE Cutaneous squamous cell carcinoma (cSCC) is the second most common nonmelanoma skin cancer and commonly affects the head and neck. Increasing regional reports of aggressive cases warrant an analysis of population-based trends of cSCC of the head and neck. OBJECTIVE To assess demographic, clinical, and survival trends among patients with cSCC of the external lip. DESIGN, SETTING, AND PARTICIPANTS This was a retrospective, population-based cohort study of 15 171 cases of cSCC of the external lip registered in the Surveillance, Epidemiology, and End Results (SEER) database between 1975 and 2016. Statistical analyses were conducted in October 2020. MAIN OUTCOMES AND MEASURESThe primary outcome was clinical characteristics (tumor site, stage, and tumor grade). Demographic characteristics, incidence, treatment characteristics, and survival outcomes were also assessed. RESULTSIn total, 15 171 cases of cSCC were extracted from the SEER database (80.3% of patients were male, and 97.0% identified as being of White race/ethnicity). Incidence among male patients decreased from 4.4 to 0.8 per 100 000 during the study period, whereas the female patients' share cases increased from 8.4% in 1975 to 1979 to 26.1% by 2016. Cases increased in the US Pacific Coast and eastern regions, and along...

Trends in cutaneous squamous cell carcinoma on the lip incidence and mortality in the United States, 2000–2019

“…People with fair skin have less melanin and less protection against UVR ( 20 – 22 ). Consistent with the results of previous studies, cSCC on the lips was most common in white people ( 22 ) and less common in black people, Indians, and Asians ( 23 , 24 ). It is more common in men than in women, with a male-to-female ratio of up to 4:1 ( 22 , 25 ).…”

“…cSCC on the lips is prevalent in people over 40 years of age, with the highest incidence in 60–79 years, and incidence-based morbidity increases over 80 years old. The elderly were relatively vulnerable, and the 5-year disease-specific survival rate of patients aged over 75 years old, especially those over aged 85 years old, is relatively poor ( 23 ). A study has found that old age is not a risk factor for poorer survival in metastatic cSCC on the lips, which might be limited to metastatic cSCC on the lips disease ( 48 ).…”

Sex Disparity for Patients with Cutaneous Squamous Cell Carcinoma of the Head and Neck: A Systematic Review

“… Proportion of males with cSCC of the total head and neck region [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 ...…”

“… Proportion of males with cSCC of lips [ 17 , 21 , 23 , 35 , 38 , 45 , 48 , 49 , 51 , 54 , 62 , 70 ]. …”