Digital Interventions to Modify Skin Cancer Risk Behaviors in a National Sample of Young Adults: Randomized Controlled Trial.

BACKGROUND: Young adults engage in behaviors that place them at risk for skin cancer. Dissemination of digital health promotion interventions via social media is a potentially promising strategy to modify skin cancer risk behaviors by increasing UV radiation (UVR) protection and skin cancer examinations. OBJECTIVE: This study aimed to compare 3 digital interventions designed to modify UVR exposure, sun protection, and skin cancer detection behaviors among young adults at moderate to high risk of skin cancer. METHODS: This study was a hybrid type II effectiveness-implementation randomized controlled trial of 2 active interventions, a digital skin cancer risk reduction intervention (UV4.me [basic]) compared with an enhanced version (UV4.me2 [enhanced]), and an electronic pamphlet (e-pamphlet). Intervention effects were assessed over the course of a year among 1369 US young adults recruited primarily via Facebook and Instagram. Enhancements to encourage intervention engagement and behavior change included more comprehensive goal-setting activities, ongoing proactive messaging related to previously established mediators (eg, self-efficacy) of UVR exposure and protection, embedded incentives for module completion, and ongoing news and video updates. Primary outcome effects assessed via linear regression were UVR exposure and sun protection and protection habits. Secondary outcome effects assessed via logistic regression were skin self-exams, physician skin exams, sunscreen use, indoor tanning, and sunburn. RESULTS: The active interventions increased sun protection (basic: P=.02; enhanced: P<.001) and habitual sun protection (basic: P=.04; enhanced P=.01) compared with the e-pamphlet. The enhanced intervention increased sun protection more than the basic one. Each active intervention increased sunscreen use at the 3-month follow-up (basic: P=.03; enhanced: P=.01) and skin self-exam at 1 year (basic: P=.04; enhanced: P=.004), compared with the e-pamphlet. Other intervention effects and differences between the Basic and Enhanced Intervention effects were nonsignificant. CONCLUSIONS: The active interventions were effective in improving several skin cancer risk and skin cancer prevention behaviors. Compared with the basic intervention, the enhanced intervention added to the improvement in sun protection but not other behaviors. Future analyses will explore intervention engagement (eg, proportion of content reviewed). TRIAL REGISTRATION: ClinicalTrials.gov NCT03313492; http://clinicaltrials.gov/ct2/show/NCT03313492.

Sunscreen use and affordability attitudes based on ethnicity, socioeconomic status, and Fitzpatrick skin type.

IMPORTANCE: One in five Americans will develop skin cancer during their lifetime. While use of sunscreen can help prevent the development cutaneous cancer, regular use remains low nationwide. OBJECTIVE: To assess and better understand health care consumer preferences for sun protection products and perceived product accessibility and availability based on socioeconomic factors, race, and ethnicity. DESIGN: This quantitative survey study was conducted March through June of 2023. SETTING: Participants were recruited from two university family medicine clinical sites in the Buffalo, New York area, one located in a low and one located in a middle-to-upper socioeconomic neighborhood. PARTICIPANTS: Eligible participants were 18 years or older, fluent in English, and residents of the Buffalo, New York area. Surveys and consent forms were distributed by scripted verbal invitation, inviting all clinic patients who met eligibility criteria to participate. Participants were asked to self-report their racial/ethnic group as well as other demographic information including age, gender identification, household income, and household size. Information regarding sun exposure behaviors, and affordability/access was obtained using a combination of multiple choice and yes/no questions. A total of 405 participants were recruited. After excluding 235 incomplete responses, 170 surveys were available for analysis. INTERVENTIONS: None. MAIN OUTCOMES AND MEASURES: Our study aim was to expose health care consumer preferences as well as barriers to access based on socioeconomic factors, race, and ethnicity. RESULTS: Using a 25-question anonymous survey, 405 participants from two university family medicine clinical sites representing low- and middle-to-high-income neighborhoods, participated in the survey. 170 participants completed the survey questions and were included for analysis. Of those, 61.8% identified as female, 37.6% as male, and 0.6% as other. 51.2% of participants identified as lower income, 38.2% as middle-income, and 10.6% as upper income. The results of the survey revealed disparities in sunscreen use and affordability perceptions across demographic groups. Compared with Hispanics, Caucasians exhibited higher rates of sunscreen use (85 Caucasians, 7 Hispanics; p = 0.0073), prioritized SPF (95 Caucasians, 10 Hispanics; p = 0.0178), and were more likely to perceive sunscreen as unaffordable (6 Caucasians, 4 Hispanics; p = 0.0269). Analysis by Fitzpatrick Skin Type demonstrated differences in sunscreen utilization, with Types I-III using more compared to Types IV-VI (70 Types I-III, 51 Types IV-VI; p = 0.0173); additionally, Type I-III individuals were significantly more likely to cite cost as barrier to sunscreen purchase (40 Type I-III, 65 Types IV-VI; p < 0.0001). Moreover, lower-income individuals were significantly more likely to perceive sunscreen as unaffordable (12 lower-income, 1 middle & upper income; p = 0.0025) and cited cost as a barrier to purchase (46 lower-income, 59 middle & upper income; p = 0.0146) compared to middle-to-upper income counterparts. Though statistical significance was not established, respondents from middle & upper income groups reported higher sunscreen usage rates compared with their lower-income peers. CONCLUSIONS AND RELEVANCE: These findings highlight the importance of socioeconomic factors and ethnicity on accessibility to sunscreen and the impact of disparities in utilization among different ethnic and socioeconomic groups.

A prospective cohort study exploring the joint influence of sunlight exposure and tanning bed use on basal cell carcinoma, squamous cell carcinoma, and melanoma risk.

Exposure to solar ultraviolet (UV) radiation and use of UV-emitting tanning devices are known risk factors for skin cancer. Few studies have explored the interaction between these risk factors, namely how the risk of skin cancer increases among those who both have been exposed to high levels of natural sunlight and regularly use tanning beds. Nurses' Health Study II followed 116,430 women, aged 25-42, from 1991 to 2011. Cumulative average UV exposure was based on participants' residences at follow-up periods. History of severe sunburn during ages 15-20 was used as a proxy for early-life sunlight exposure. Tanning bed use in early life data was collected. Participants reported melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC) diagnoses. We built multivariable Cox regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of skin cancer associated with joint effects of sunlight exposure and tanning bed use. Participants with high sunlight exposure and tanning bed use during high school/college had an increased risk of BCC (HR = 1.53, 95% CI 1.37-1.71, Pinteraction=0.01; vs. low sun exposure and no tanning bed use). Participants with a history of severe sunburns and tanning bed use during high school/college were at increased risk of BCC (HR = 1.62, 95% CI 1.47-1.79, Pinteraction=0.02; vs. no sunburns and no tanning bed use). No significant interactions were found between sunlight exposure and tanning bed use on SCC and melanoma risk. We found significant interactions between sunlight exposure and tanning bed use on the risk of BCC.

A photoaging smartphone application to promote sun safety behaviors among youth in late childhood and adolescence.

BACKGROUND: Ultraviolet (UV)-exposure behaviors can directly impact an individual's skin cancer risk, with many habits formed during childhood and adolescence. We explored the utility of a photoaging smartphone application to motivate youth to improve sun safety practices. METHODS: Participants completed a preintervention survey to gather baseline sun safety perceptions and behaviors. Participants then used a photoaging mobile application to view the projected effects of chronic UV exposure on participants' self-face image over time, followed by a postintervention survey to assess motivation to engage in future sun safety practices. RESULTS: The study sample included 87 participants (median [interquartile (IQR)] age, 14 [11-16] years). Most participants were White (50.6%) and reported skin type that burns a little and tans easily (42.5%). Preintervention sun exposure behaviors among participants revealed that 33 (37.9%) mostly or always used sunscreen on a sunny day, 48 (55.2%) experienced at least one sunburn over the past year, 26 (30.6%) engaged in outdoor sunbathing at least once during the past year, and zero (0%) used indoor tanning beds. Non-skin of color (18 [41.9%], p = .02) and older (24 [41.4%], p = .007) participants more often agreed they felt better with a tan. Most participants agreed the intervention increased their motivation to practice sun-protective behaviors (wear sunscreen, 74 [85.1%]; wear hats, 64 [74.4%]; avoid indoor tanning, 73 [83.9%]; avoid outdoor tanning, 68 [79%]). CONCLUSION: The findings of this cross-sectional study suggest that a photoaging smartphone application may serve as a useful tool to promote sun safety behaviors from a young age.

Does Male Skin Care Content on Instagram Neglect Skin Cancer Prevention?

This research letter assesses male skin care content on social media in order to bring to light the lack of content regarding skin cancer prevention posted on Instagram for male audiences.

A Prospective Cohort Study Exploring the Joint Influence of Sunlight Exposure and Tanning Bed Use on Basal Cell Carcinoma, Squamous Cell Carcinoma, and Melanoma Risk.

Exposure to solar ultraviolet (UV) radiation and use of UV-emitting tanning devices are known risk factors for skin cancer. Few studies have explored the interaction between these risk factors, namely how the risk of skin cancer increases among those who both have been exposed to high levels of natural sunlight and regularly use tanning beds. Nurses' Health Study II followed 116,430 women, aged 25-42, from 1991 to 2011. Cumulative average UV exposure was based on participants' residences at follow-up periods. History of severe sunburn during ages 15-20 was used as a proxy for early-life sunlight exposure. Tanning bed use in early life data was collected. Participants reported melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC) diagnoses. We built multivariable Cox regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of skin cancer associated with joint effects of sunlight exposure and tanning bed use. Participants with high sunlight exposure and tanning bed use during high school/college had an increased risk of BCC (HR=1.53, CI 1.37-1.71, P interaction =0.01; vs. low UV exposure and no tanning bed use). Participants with a history of severe sunburns and tanning bed use during high school/college were at increased risk of BCC (HR=1.62, CI 1.47-1.79, P interaction =0.02; vs. no sunburns and no tanning bed use). No significant interactions were found between sunlight exposure and tanning bed use on SCC and melanoma risk. We found significant interactions between sunlight exposure and tanning bed use on the risk of BCC.

Sharing and seeking information about skin cancer risk and prevention among Hispanic people from Florida and Puerto Rico.

Objective: To explore factors associated with communication and information-seeking after receipt of skin cancer prevention information among Hispanic individuals. Methods: Multivariable logistic regression was used to analyze existing data on demographics, personal experience, salience, and beliefs variables collected from Hispanic individuals to determine independent associations with sharing and seeking information about skin cancer prevention. Results: Of 578 participants, 53% reported any communication about skin cancer prevention behaviors or skin cancer genetic risk; and 31% and 21% sought additional information about preventive behaviors or genetic risk, respectively. Female sex, greater perceived severity, higher comparative chance of getting skin cancer, and lower health literacy were associated with greater communication, while having no idea of one's own skin cancer risk was related to less communication. Greater health numeracy and higher cancer worry were associated with information-seeking about prevention behaviors and genetic risk. Conclusion: Up to half of participants reported communication or information-seeking, although factors associated with specific activities differed. Future studies should evaluate how to promote communication behaviors in the Hispanic community and how sharing and seeking information influence an individual's network prevention practices. Innovation: Several factors related to communication behaviors among Hispanic people after obtaining skin cancer prevention information were identified.Trial registration: This trial was registered on clinicaltrials.gov (NCT03509467).

Patient Perception of Skin Cancer Reduction by Nicotinamide Correlates With Use.

Introduction Nicotinamide (Vitamin B3) has been shown to reduce the rate of non-melanoma skin cancers by 23%, yet most patients do not know that this supplement reduces skin cancer. Understanding patient beliefs about skin cancer reduction attributed to nicotinamide is important to appropriately counsel patients on oral supplement use and ultimately to prevent non-melanoma skin cancers. Objective The objective of this study was to determine the association between nicotinamide use and perceived efficacy in skin cancer reduction. Methods Patients who underwent Mohs surgery in 2019 were sent an online survey assessing nicotinamide use, efficacy compared to sunscreen, and perceived skin cancer risk reduction. Results Data from 50 surveys revealed a perceived risk reduction attributed to nicotinamide of 31.2% for basal cell carcinoma (BCC), 30.2% for squamous cell carcinoma (SCC), and 24.3% for melanoma. In the subset of respondents taking nicotinamide, the perceived risk reduction was significantly higher at 41.2% for BCC and 38.3% for SCC (p<0.05) and positively correlated with reported nicotinamide use (p<0.05). The perceived risk reduction of melanoma was not significantly increased in patients taking nicotinamide (31.6%); however, the perceived risk reduction was correlated with nicotinamide use (p<0.05). In addition, 15.6% of respondents believed that nicotinamide was more effective than sunscreen at preventing skin cancer. Conclusion A larger perceived reduction of non-melanoma skin cancers attributed to nicotinamide is associated with increased oral nicotinamide use. Better patient education regarding the reduction of skin cancers with oral nicotinamide will need to be implemented to change patients' perceptions of the value of nicotinamide.

Understanding the Perceived Relationship between Sun Exposure and Melanoma in Atlantic Canada: A Consensual Qualitative Study Highlighting a "Sunscreen Paradox".

Globally, cutaneous melanoma (CM) incidence is increasing, with sun exposure identified as a key modifiable risk factor. The Atlantic provinces of Canada display varied CM incidence rates: New Brunswick aligns with the national average, while Nova Scotia and Prince Edward Island exceed it, and Newfoundland and Labrador fall below this benchmark. We investigated the relationship between sun exposure and CM in these provinces. Twenty-two focus groups encompassing 95 Atlantic Canada residents were conducted and transcribed. A thematic analysis was conducted in MAXQDA using the social-ecological model as a framework. Residents of high-CM incidence provinces demonstrated greater sun exposure awareness, consulting UV indices, and using sunscreen and sun-protective clothing. However, they received greater UV exposure due to warmer climates and outdoor work and cultural activities. Conversely, those in low-incidence provinces used sunscreen and sun-protective clothing less often, engaged in occupations and hobbies affording less sun exposure, and lived in cooler climates. Our data supports a possible "sunscreen paradox", whereby increased sunscreen use is correlated with augmented sun exposure, leading to a deceptive sense of security. Public health initiatives in Atlantic Canada promoting sun safety must address this paradox while integrating community-specific behaviors and norms in order to develop tailored campaigns.

Sun exposure practices, attitudes and knowledge among students and teachers at a University School of Health Sciences in Ecuador.

Skin cancer incidence is increasing worldwide. Late adolescence and young adulthood are fundamental stages of life to acquire good sun exposure practices, regarding both personal involvement in skin cancer prevention and being a role model for others, especially in a health education environment. This descriptive cross-sectional study is based on the validated CHACES questionnaire to study sun exposure and photoprotection behavior among students and teachers at the School of Health Sciences in the National University of Chimborazo, Riobamba (Ecuador). University members (814 students (89.8 %) and 93 teachers (10.2 %)) were studied, with a predominance of females and light-skin phototypes in both groups. Similar results were obtained regarding sun exposure, with higher recreative exposure in the teachers' group and higher occupational exposure in students. However, students significantly showed lower avoiding midday sun (41.9 % vs 60.9 %), and lower use of sunglasses (10.1 % vs. 41.6 %). Attitudes towards the sun and photoprotection knowledge issues were also equivalent between students and teachers (6.1/10 vs 6.2/10). Students' sunburn rate last year reaches 88.4 % and 52.7 % in teachers (p < 0.001). Using a multivariable logistic regression model, we identified risk factors associated with a greater risk of sunburn in our population. This study highlights areas to be improved regarding knowledge, attitudes and, especially, practices of photoprotection, among students and teachers at the University of Chimborazo. These results point out that awareness-raising campaigns should be implemented to reduce sunburns, morbidity and mortality of skin cancer in this environment.

Patterns of Sun Protection Behaviours among Australian Adolescents and Adults over a Six-Year Period.

The major cause for skin cancer is the excessive and unprotected exposure to ultraviolet radiation (UVR), which can be prevented by engaging in sun protection behaviours. As longitudinal studies on both adolescents' and adults' performances of sun protection behaviours are limited, the current study aimed to investigate changes in sun protection in these population segments in Western Australia, a region with high annual UVR. During six summer seasons (2015/16 to 2020/21), cross-sectional surveys were conducted among 1806 adolescents (14 to 17 years old) and 1808 adults (18-45 years old), investigating the frequency of five sun protection behaviours (wearing clothing, applying sunscreen, wearing a hat, wearing sunglasses, and seeking shade) and sun avoidance (staying indoors). Over the six-year period, staying indoors increased in both groups. Among adolescents, a decrease in wearing clothing and sunglasses and an increase in seeking shade was demonstrated, and hat and sunscreen use remained relatively stable. Among adults, an increase in sunscreen use was shown, whereas all other sun-related behaviours remained consistent over the six-year period. The results from this study can provide directions for health communications focusing on improving sun protection behaviours among both adolescent and adult populations.

Assessing Skin Cancer Risk Factors, Sun Safety Behaviors and Melanoma Concern in Atlantic Canada: A Comprehensive Survey Study.

BACKGROUND: The incidence of cutaneous melanoma (CM) is increasing at an alarming rate in Canada and elsewhere around the world. Significant regional differences in CM incidence have been identified in Atlantic provinces. The goal of this study is to compare ultraviolet exposure, sun protective behaviours, level of worry and baseline CM knowledge in provinces with a high versus low incidence of CM as well, as between various demographic groups. METHODS: A cross-sectional survey study was conducted in Atlantic provinces between July 2020 and August 2022. All participants aged ≥ 16 years with a completed survey were eligible. Survey responses were summarized using frequency counts, percentages, and means. Two-sided Z-tests for equality of proportions and logistic regression models were used to compare the survey results between geographic and demographic groups. RESULTS: In total, 7861 participants were included (28.0% men; mean age 61.3 years; response rate 28%). Our results (gender- and age-adjusted odds ratio, 95% confidence interval) show that high-incidence provinces for CM (Prince Edward Island and Nova Scotia) had significantly more sunburns (OR 2.00, 1.72-2.31), total sun exposure (OR 2.05, 1.68-2.50), recreational sun exposure (OR 1.95, 1.61-2.35) and tans (OR 1.77, 1.53-2.05) than individuals in low-incidence provinces (Newfoundland and Labrador). However, individuals in high-incidence provinces displayed more protective behaviors: there were less tanning bed users (OR 0.82, 0.71-0.95), they checked their skin more frequently for new moles (OR 1.26, 1.06-1.51) and practiced more sun protection overall. Additional analyses are presented based on education, income, sexual orientation and gender. DISCUSSION: These findings suggest that future efforts aimed at reducing the CM burden in Atlantic Canada should be tailored for target geographic and/or demographic groups. LIMITATIONS: the study participants are not representative of the population in Atlantic Canada due to recruitment strategies.

Sunburn and sun protection during recreational outdoor sport in summer: Findings from the German general population aged 16-65 years.

BACKGROUND: Sunburn can increase one's risk of developing skin cancer. We aimed to quantify the prevalence of sunburn during recreational outdoor sport (ROS) in summer, to explore the use of different sun protection measures, and to examine factors associated with sunburn during ROS using a population-based sample from Germany. METHODS: For this cross-sectional study, 2081 individuals aged 16-65 years who reported being engaged in ROS in summer were surveyed via standardized telephone interviews in 2020 (National Cancer Aid Monitoring, NCAM). RESULTS: Overall, 16.7% reported experiencing at least one sunburn during ROS in the past twelve months. Sunburn occurrence was negatively associated with the age of the participants (e.g. OR = 0.49 in 56-65 year-olds, p < .001), and positively associated with skin type I/II (OR = 1.55, p < .001) and with having a higher number of nevi (OR = 1.42, p = .005). While wearing sleeved shirts was the most frequently-used sun protection measure during ROS (74.9%), wearing headgear was least common in our sample (29.0%). In multivariate analyses, sunburn was positively associated with the use of sun protection measures (e.g. OR = 1.32 for wearing sleeved shirts, p = .02). CONCLUSIONS: Our nationwide data show that ROS is one of the settings where sun protection should play a greater role. Especially in organized sports, particular attention should be devoted to organizational (e.g. exercise outside peak hours) or contextual measures (e.g. shade by the natural or built environment) to prevent skin cancer in later life.

Metastatic Melanoma: A Consequence of the COVID-19 Pandemic.

Metastatic melanoma, though less common than other skin cancers, remains one of the deadliest, particularly in late-stage disease. Our report aims to highlight the importance of early detection and treatment to reduce the morbidity, mortality, and significant disfigurement associated with advanced melanoma. The subject of this case is an 81-year-old female who presented to our emergency department as a trauma patient after being found lying down by a neighbor for an unknown amount of time. She was discovered to have a large fungating nasal mass which was subsequently diagnosed as highly invasive melanoma. A thorough workup revealed a metastatic cerebellar lesion, a large ulcerated basal cell carcinoma eroding her calvarium, and a hemorrhagic lesion within her internal capsule that left her with right-sided hemiparesis. During hospitalization, she underwent palliative resection of the primary nasal mass with flap reconstruction, radiation therapy for her cerebellar lesion, and daily physical therapy. Additional surgery was required for hematoma evacuation and pedicle dissection. Though lockdowns were an important part of the pandemic, they were not without their drawbacks, many of which are still being elucidated. Particularly, by utilizing telehealth services, our patient may have had earlier recognition of her melanoma and a better outcome. Regardless, enhancing patient education and maintaining access to care even through lockdowns poses a potential target for improving melanoma survivability while decreasing associated morbidity.

Setting-based skin cancer prevention at the workplace: A survey among German outdoor workers.

BACKGROUND: Outdoor workers are at increased risk of developing skin cancer. Setting-based prevention at the workplace can reduce the UV exposure of outdoor workers through appropriate technical or organizational measures. We explored the implementation of setting-based UV protection at the workplace in Germany from the perspective of outdoor workers. METHODS: A Germany-wide sample of 319 outdoor workers from different employment sectors (64.3% male) was surveyed via telephone on different technical and organizational measures for UV protection at the workplace. Bivariate analyses were performed to explore associations with job-related characteristics. RESULTS: In general, 28.0% were rarely or never provided with a place in the shade during working hours, and 27.4% rarely or never provided with a shaded place during breaks. One-third had rarely or never the opportunity to work in the shade on hot summer days. Overall, 51.9% reported receiving protective clothing from their employer, 45.5% were provided with headgear, and 25.1% with sunscreen. About one-third had often or always the option of starting work earlier in the morning on hot summer days to work less in the sun, while 18.6% had to work overtime on such days. One-third (35.4%) had been educated at work about risks of solar radiation and sun protection measures. CONCLUSIONS: Our study is among the first to present findings on the implementation of different setting-based UV protection measures at the workplace and provides starting points for employers and policy makers to improve UV protection at the workplace.

Incorporating Decision Simulation Technology in a Skin Cancer Prevention E-Training for Massage Therapists.

Decision simulation technology is known to augment health practitioner education and training; little is known about its use for educating lay health practitioners about cancer prevention. We report the development and evaluation of a decision simulation component of a skin cancer risk reduction electronic training (e-training) for massage therapists (MTs). Simulation facilitated tracking and analysis of MTs' selected dialog options leading to client-focused helping conversations (MT conversations intended to encourage client pro-health behavior) regarding skin cancer risk reduction. The tracking also enabled further assessment of the e-training competencies. We constructed five decision simulation cases in the DecisionSim™ online platform, mimicking MT-client encounters pertaining to skin cancer risk reduction, allowing MTs to apply training knowledge to initiate a helping conversation. We scored each simulation by tracking conversation pathways via selected dialog options (optimal, feedback required, suboptimal), analyzing total scores and real time spent on each case. MTs rated satisfaction with the simulations on a 5-point Likert scale. Eighty-one MTs completed the simulations in an average of 2.7 min. Most (91%) MTs selected feedback required or suboptimal dialog options for at least one of the five cases, often incorrectly choosing conversation statements reflecting their own feelings. The majority (86%) agreed/strongly agreed that they enjoyed the simulations (mean score 4.31); 92% found the simulations helpful to include in the training (mean score 4.36). Decision simulations integrated into e-training are useful for assessing lay practitioners' practical application of cancer risk reduction knowledge and skills and use of appropriate helping conversations.

Preventative Options and the Future of Chemoprevention for Cutaneous Tumors.

Chemoprophylaxis against nonmelanoma skin cancer (NMSC) should be considered in high-risk populations such as those with certain genetic disorders, immunosuppressive states, chronic radiation, excessive UV exposure, or extensive personal or family history of NMSC. The methods for chemoprevention have progressed beyond traditional sunscreen into more effective strategies including DNA repair enzymes, nicotinamide, systemic retinoids, and nonsteroidal anti-inflammatory drugs. Other therapies are still being investigated and include treatments that target premalignant lesions, capecitabine, hedgehog inhibitors, difluoromethylornithine, metformin, and nutritional factors.