Statin use and non-melanoma skin cancer risk: a meta-analysis of randomized controlled trials and observational studies

Exposome and basal cell carcinoma: a multicenter case-control study

BACKGROUND

While ultraviolet radiation (UVR) present in sunlight is recognized as the main etiological agent of skin cancer, the most frequent form of which is basal cell carcinoma (BCC), other exposome factors like pollution, diet, and lifestyle may also contribute. This study aimed to investigate the association of BCC and exposome-related factors in the Spanish population.

METHODS

BCC cases (n = 119) and controls (n = 127) with no history of skin cancer were recruited between April 2020 and August 2022 by 13 dermatologists throughout Spain in this prospective multicenter case-control study.

RESULTS

The BCC group had a higher proportion of outdoor workers, more years of UVR exposure, and a greater consumption of drugs (statins, ASA, hydrochlorothiazide, ACE inhibitors and omeprazole), P < 0.05. Avoidance of sun exposure was the most used photoprotection measure in both groups. The use of hats or caps was higher in the BCC group (P = 0.01). The solar protection factor (SPF) used 15 years previously was higher in the control group (P = 0.04). The control group had a higher daily screen time (P < 0.001), and practiced more relaxation activities (P = 0.03). Higher linolenic acid intake and lower coffee consumption were the only dietary variables associated with BCC (P < 0.05). Statistical significance for all the aforementioned variables was maintained in the multivariate analysis (P < 0.05).

CONCLUSIONS

The study found a significant association between BCC and multiple exposome-related factors in addition to chronic sun exposure in the Spanish population. Primary prevention strategies should target specific populations, such as outdoor workers, promoting sun-safe behaviors and stress-reducing activities, and also adequate skin photoprotection in patients on certain medications associated with increased BCC risk.

The Influence of the Exposome in the Cutaneous Squamous Cell Carcinoma, a Multicenter Case-Control Study

INTRODUCTION

The concept of exposome refers to the total of harmful and beneficial environmental exposures that can help predict the organism's biological responses over time. Ultraviolet radiation (UVR) from sun exposure has been recognized as the main etiological agent of skin cancer, and squamous cell carcinoma (SCC) is one most commonly associated with chronic exposure. However, in recent years, evidence suggests that lifestyle, environmental pollution, and contaminants in water and food can have an influence.

OBJECTIVES

To study the relationship between SCC and sun exposure, pollution, stress, and lifestyle in a Spanish cohort.

MATERIALS AND METHOD

A multicenter case-control study was carried out in which 13 dermatologists from different regions of Spain recruited cases and controls between April 2020 and August 2022. The group of cases were patients diagnosed with SCC and, as a control group, people who attended Dermatology consultations as companions with no history of skin cancer.

RESULTS

A total of 62 patients with SCC and 126 controls were included (62.9% males, median age 76.46 (10.1) and 33.3%, median age 55.7 (15), respectively). The SCC group had experienced more outside work than the controls (75% vs. 22.4%, p < 0.001), less recreational exposure (sunbathing, p = 0.05, and outdoor sports, p = 0.01), and a lower annual income (p = 0.01), with an increase in tobacco exposure (p < 0.001), without differences in other carcinogens, such as ionizing radiation or chemical exposure. The control group had a higher daily screentime use (p < 0.001) and practiced more relaxation activities (p = 0.03). A higher linolenic acid intake and lower coffee consumption were the only dietary variables associated with SCC (p < 0.05). Some chronic medications (anxiolytics, antidepressants, beta-blockers, statins, hydrochlorothiazide, ACE inhibitors, metformin, and omeprazole) were also statistically associated with SCC. Statistical significance for all aforementioned variables was maintained in the multivariate analysis (p < 0.05).

CONCLUSIONS

The study found a significant association between SCC and multiple exposome-related factors in addition to chronic sun exposure in the Spanish population. Primary prevention strategies should target specific populations, such as outdoor workers promoting sun-safe behaviors and stress-reducing activities, in addition to adequate skin photoprotection in patients under certain medications associated with SCC.

Association between statins exposure and risk of skin cancer: an updated meta-analysis

This study aimed to investigate the relationship between statin (lipophilic statin and hydrophilic statin) exposure and the risk of skin cancer. The incidence of skin cancer under statin exposure was used as the primary outcome, and the relevant studies were screened from Web of Science, PubMed, Cochrane Library, and EBSCO electronic database until September 2022. Ten observational studies and two randomized controlled trials (RCTs) were included. The statistical results indicated that in lipophilic statins, the exposed group had a higher risk of skin cancer than the non-exposed group (OR: 1.09, P = 0.003). However, compared with the non-exposed group, there was no significant difference between hydrophilic statins exposure and the incidence of skin cancer (OR: 1.02, P = 0.341). Further subgroup analysis of the subtypes of statins revealed that compared with the non-exposed group, exposure to lovastatin (OR: 1.18, P = 0.048) or simvastatin (OR: 1.11, P < 0.001) was a risk factor for skin cancer. Besides, subgroup analysis based on the subtypes of skin cancer demonstrated that the risks of melanoma (OR: 1.13, P = 0.009), basal cell carcinoma (BCC) (OR: 1.05, P = 0.036), and squamous cell carcinoma (SCC) (OR: 1.13, P = 0.026) under lipophilic statin exposure were significantly higher than those in the non-exposed group. On the contrary, compared with the non-exposed group, the risk of BCC was significantly reduced under the exposure of hydrophilic statins (OR: 0.93, P = 0.031). This study showed that the relationship between statin exposure and skin cancer risk was affected by the subtypes of statins and skin cancer subtypes.

Statin Use and Skin Cancer Risk: A Prospective Cohort Study

Epidemiological studies on statin use in relation to skin cancer risk are scarce and yielded conflicting results. We explored this association in Etude Epidémiologique auprès de femmes de l'Education Nationale, a prospective cohort of French women born in 1925-1950. Health and lifestyle data were self-reported biennially and matched with drug reimbursement data, allowing the identification of participants' statin use since 2004. Multivariable cause-specific hazards regression models adjusted for skin cancer risk factors estimated hazard ratios with 95% confidence intervals. Over 2004-2014, 455 cutaneous melanoma, 1,741 basal cell carcinoma, and 268 squamous cell carcinoma cases were ascertained among 62,473 women. Compared with never use, there were no associations between ever use of statins and melanoma (hazard ratio = 1.16, 95% confidence interval = 0.94-1.44) or squamous cell carcinoma (hazard ratio = 0.89, 95% confidence interval = 0.66-1.19) risks and a decrease in basal cell carcinoma risk with ever use of statins (hazard ratio = 0.89, 95% confidence interval = 0.79-0.996). We found no trend of increasing or decreasing risks with dose, duration of use, time since first use, or age at first use and no statistically significant effect modification by pigmentary traits or residential UVR exposure. Because of the limited number of studies evaluating the associations between the use of statins and the risks of melanoma, basal cell carcinoma, and squamous cell carcinoma, these findings would deserve further investigation in other settings.

The Risk of Cutaneous Squamous Cell Carcinoma Among Patients with Type 2 Diabetes Receiving Hydrochlorothiazide: A Cohort Study

BACKGROUND

Because of continuous hyperglycemia and hyperinsulinemia and the use of photosensitizing drug, hydrochlorothiazide (HCTZ), the risk of cutaneous squamous cell carcinoma (cSCC) might be increased among patients with diabetes. This study aimed to estimate the risk of cSCC among HCTZ users with type 2 diabetes, and to determine whether thiazide-like diuretics, another drug in the same class with HCTZ, would be safer.

METHODS

We linked the benchmarking database in Dutch primary care, the Netherlands Cancer Registry, and the Dutch Personal Records Database (1998-2019). All 71,648 patients were included, except for those who had a history of skin cancer prior to cohort entry. We used Cox modeling to estimate the HRs and 95% confidence intervals for cSCC. The model was adjusted by cumulative exposure to each antihypertensive, age, sex, smoking, body mass index, blood pressure, serum creatinine, other confounding drug use at cohort entry, and cohort entry year.

RESULTS

There were 1,409 cSCC events (23 among thiazide-like diuretics users), during a follow-up of 679,789 person-years. Compared with no HCTZ use, the adjusted HRs for HCTZ use were 1.18 (1.00-1.40) for ≤2 years, 1.57 (1.32-1.88) for 2 to 4 years, and 2.09 (1.73-2.52) for >4 years. The HR was 0.90 (0.79-1.03) for an additional year of thiazide-like diuretic use.

CONCLUSIONS

In patients with diabetes, exposure to HCTZ for >2 years is associated with an increased risk of cSCC, whereas no increased risk associated with thiazide-like diuretics was observed.

IMPACT

The potential increased risk of cSCC should be a consideration when prescribing HCTZ, with thiazide-like diuretics offering a safer alternative.

Photosensitizing Medications and Skin Cancer: A Comprehensive Review

(1) The incidence of skin cancer is increasing in the United States (US) despite scientific advances in our understanding of skin cancer risk factors and treatments. In vitro and in vivo studies have provided evidence that suggests that certain photosensitizing medications (PSMs) increase skin cancer risk. This review summarizes current epidemiological evidence on the association between common PSMs and skin cancer. (2) A comprehensive literature search was conducted to identify meta-analyses, observational studies and clinical trials that report on skin cancer events in PSM users. The associated risks of keratinocyte carcinoma (squamous cell carcinoma and basal cell carcinoma) and melanoma are summarized, for each PSM. (3) There are extensive reports on antihypertensives and statins relative to other PSMs, with positive and null findings, respectively. Fewer studies have explored amiodarone, metformin, antimicrobials and vemurafenib. No studies report on the individual skin cancer risks in glyburide, naproxen, piroxicam, chlorpromazine, thioridazine and nalidixic acid users. (4) The research gaps in understanding the relationship between PSMs and skin cancer outlined in this review should be prioritized because the US population is aging. Thus the number of patients prescribed PSMs is likely to continue to rise.

Statins are associated with increased risk of squamous cell carcinoma of the skin: a whole-population study from Iceland

Statins have been associated with an increased risk of keratinocyte carcinoma but data are limited and conflicting. Statins are hypothesized to contribute to KC through immunomodulation. A whole-population case-control study of the Icelandic population was conducted using the Icelandic Cancer Registry and Icelandic Prescription Medicine Register. These are high-quality registers which include all cancer diagnoses, as well as every prescription in the country. Cases included all first-time histologically confirmed diagnoses of (BCC), in situ squamous cell carcinoma (SCCis) and invasive SCC between 2003 and 2017. Each case was paired with 10 age- and sex-matched controls. Multivariate conditional logistic regression analysis was performed. Four thousand seven hundred patients with BCC, 1167 patients with SCCis and 1013 patients with invasive SCC were identified and paired with 47,292, 11,961 and 10,367 controls, respectively. Overall statin use was associated with an increased risk of invasive SCC and SCCis but not BCC (adjusted OR [95% CI]: 1.29 [1.11-1.50]; 1.43 [1.24-1.64]; 1.03 [0.95-1.12], respectively). Subgroup analysis demonstrated that statins were significantly associated with invasive SCC and SCCis in patients over 60, but not in those under 60. Atorvastatin was only associated with an increased risk of SCCis; whereas, simvastatin was associated with an increased risk of both invasive SCC and SCCis. This whole-population study of Iceland demonstrates that statin exposure is associated with increased risk of SCC, but not BCC, in a low UV environment. The reasons are unclear, but our results may suggest that individuals receiving atorvastatin and simvastatin have differing levels of baseline keratinocyte cancer risk or that properties of a statin other than 'statin intensity' affect association with SCC.

Metformin is associated with decreased risk of basal cell carcinoma: A whole-population case-control study from Iceland

BACKGROUND

Metformin has anticarcinogenic properties and is also known to inhibit the sonic hedgehog pathway, but population-based studies analyzing the potential protective effect for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are needed.

OBJECTIVES

To delineate the association between metformin use and invasive SCC, SCC in situ (SCCis), and BCC.

METHODS

A population-based case-control study design was employed using all 6880 patients diagnosed in Iceland between 2003-2017 with first-time BCC, SCCis, or invasive SCC, and 69,620 population controls. Multivariate odds ratios (ORs) were calculated using conditional logistic regression.

RESULTS

Metformin was associated with a lower risk of developing BCC (OR, 0.71; 95% confidence interval [CI], 0.61-0.83), even at low doses. No increased risk of developing SCC was observed. SCCis risk was mildly elevated in the 501-1500 daily dose unit category (OR, 1.40; 95% CI, 1.00-1.96).

LIMITATIONS

This study was retrospective in nature with the inability to adjust for ultraviolet exposure, Fitzpatrick skin type, and comorbidities.

CONCLUSION

Metformin is associated with decreased risk of BCC development, even at low doses. Metformin might have potential as a chemoprotective agent for patients at high risk of BCC, although this will need confirmation in future studies.

Assessment of Deep Learning Using Nonimaging Information and Sequential Medical Records to Develop a Prediction Model for Nonmelanoma Skin Cancer

Importance

A prediction model for new-onset nonmelanoma skin cancer could enhance prevention measures, but few patient data-driven tools exist for more accurate prediction.

Objective

To use machine learning to develop a prediction model for incident nonmelanoma skin cancer based on large-scale, multidimensional, nonimaging medical information.

Design, Setting, and Participants

This study used a database comprising 2 million randomly sampled patients from the Taiwan National Health Insurance Research Database from January 1, 1999, to December 31, 2013. A total of 1829 patients with nonmelanoma skin cancer as their first diagnosed cancer and 7665 random controls without cancer were included in the analysis. A convolutional neural network, a deep learning approach, was used to develop a risk prediction model. This risk prediction model used 3-year clinical diagnostic information, medical records, and temporal-sequential information to predict the skin cancer risk of a given patient within the next year. Stepwise feature selection was also performed to investigate important and determining factors of the model. Statistical analysis was performed from November 1, 2016, to October 31, 2018.

Main Outcomes and Measures

Sensitivity, specificity, and area under the receiver operating characteristic (AUROC) curve were used to evaluate the performance of the models.

Results

A total of 1829 patients (923 women [50.5%] and 906 men [49.5%]; mean [SD] age, 65.3 [15.7] years) with nonmelanoma skin cancer and 7665 random controls without cancer (3951 women [51.5%] and 3714 men [48.4%]; mean [SD] age, 47.5 [17.3] years) were included in the analysis. The 1-year incident nonmelanoma skin cancer risk prediction model using sequential diagnostic information and drug prescription information as a time-incorporated feature matrix could attain an AUROC of 0.89 (95% CI, 0.87-0.91), with a mean (SD) sensitivity of 83.1% (3.5%) and mean (SD) specificity of 82.3% (4.1%). Carcinoma in situ of skin (AUROC, 0.867; -2.80% loss) and other chronic comorbidities (eg, degenerative osteopathy [AUROC, 0.872; -2.32% loss], hypertension [AUROC, 0.879; -1.53% loss], and chronic kidney insufficiency [AUROC, 0.879; -1.52% loss]) served as more discriminative factors for the prediction. Medications such as trazodone, acarbose, systemic antifungal agents, statins, nonsteroidal anti-inflammatory drugs, and thiazide diuretics were the top-ranking discriminative features in the model; each led to more than a 1% decrease of the AUROC when eliminated individually (eg, trazodone AUROC, 0.868; -2.67% reduction; acarbose AUROC, 0.870; -2.50 reduction; and systemic antifungal agents AUROC, 0.875; -1.99 reduction).

Conclusions and Relevance

The findings of this study suggest that a risk prediction model may have potential predictive factors for nonmelanoma skin cancer. This model may help health care professionals target high-risk populations for more intensive skin cancer preventive methods.

Regression of Periocular Basal Cell Carcinoma: A Report of Four Cases with Clinicopathologic Correlation

Objectives

To describe the spectrum of clinical and histopathological features of a case series of basal cell carcinoma (BCC) with spontaneous regression and to discuss this phenomenon.

Method

Four cases of BCC with complete/substantial regression were retrospectively identified. Patients' records were analyzed for demographic data, clinical appearance, and the postoperative course. Formalin-fixed, paraffin-embedded specimens were routinely processed and stained with hematoxylin and eosin and periodic acid Schiff.

Results

Complete (n = 1) or partial (n = 3) regression of BCC was observed in 4 patients. Two lesions at the medial canthus were histologically diagnosed as nodular BCC with significant regression. One lesion at the lower eyelid exhibited a complete regression which did not require surgical intervention. The other lesion at the lower eyelid presenting with ulceration and madarosis was excised. Scar tissue without evidence for a neoplasm was present histologically. Subsequently, the patient developed a recurrence with a histologically proven micronodular BCC.

Conclusions

BCC can show spontaneous substantial or complete regression. Histological tumor absence in lesions which are clinically suspicious for a neoplasm can be a hint for a regressive BCC. Recurrences may develop from remaining tumor islands warranting periodical clinical visits in cases of clinically as well as histologically suspected regressive BCC.

Identifying chemopreventive agents for obesity-associated cancers using an efficient, 3D high-throughput transformation assay

Obesity is associated with ~40% of cancer diagnoses but there are currently no effective preventive strategies, illustrating a need for chemoprevention. We previously demonstrated that fibroblast growth factor 2 (FGF2) from adipose tissue stimulates malignant transformation, as measured by growth in soft agar, the gold-standard in vitro transformation assay. Because the soft agar assay is unsuitable for high throughput screens (HTS), we developed a novel method using 3D growth in ultra-low attachment conditions as an alternative to growth in agar to discover compounds that inhibit transformation. Treating non-tumorigenic, skin epithelial JB6 P⁺ cells with FGF2 stimulates growth in ultra-low attachment conditions analogous to growth in the soft agar. This transformation HTS identified picropodophyllin, an insulin growth factor 1 receptor (IGF1R) inhibitor, and fluvastatin, an HMG-CoA reductase inhibitor, as potential chemopreventive agents. These compounds were validated for efficacy using two non-tumorigenic cell lines in soft agar. Another IGF1R inhibitor and other statins were also tested and several were able to inhibit growth in soft agar. This novel 3D HTS platform is fast, robust and has the potential to identify agents for obesity-associated cancer prevention.

Effect of Statin on Cancer Incidence: An Umbrella Systematic Review and Meta-Analysis

Statins are reported to reduce the risk of cancer, but the results of various published studies have been contradictory. We carried out an umbrella review to provide an overview and understand the strength of evidence, extent of potential biases, and validity of claimed associations between the use of statins and cancer incidence. We comprehensively re-analyzed the data of meta-analyses of randomized controlled trials (RCTs) and observational studies on associations between statin use and cancer incidence. We also assessed the strength of evidence of the re-analyzed outcomes, which were determined from the criteria including statistical significance of the p-value of random-effects, as well as fixed-effects meta-analyses, small study effects, between-study heterogeneity, and a 95% prediction interval. Using a conventional method to assess the significance of meta-analysis (p-value < 0.05), statins had a statistically significant effect on reducing cancer incidence in 10 of 18 types of cancer. When we graded the level of evidence, no cancer type showed convincing evidence, and four cancers (esophageal cancer, hematological cancer, leukemia, and liver cancer) showed suggestive evidence of a preventive effect. There was weak evidence of an association with six cancers, and no significance for the remaining eight cancers. None of the meta-analyses of RCTs on the association of statin and cancer incidence showed a statistical significance. Although there was a preventive effect of statin on cancer incidence in 10 of the 18 cancer types, the evidence supporting the use of statins to reduce cancer incidence was low. Therefore, the associations between statin use and cancer incidence should be carefully considered by clinicians.

Dose-response relation between serum total cholesterol levels and overall cancer risk: evidence from 12 prospective studies involving 1,926,275 participants

This study aimed to clarify the association between serum total cholesterol (TC) levels and overall cancer risk. Study-specific relative risks (RR) and 95% confidence intervals (CI) were pooled using a random-effects model, and dose-response relation was also evaluated. Twelve prospective studies were identified with a total of 1,926,275 participants and 13,1676 cases. High levels of serum TC showed an inverse association with overall cancer risk (RR for the highest versus the lowest category: 0.87, 95% CI: 0.83 ∼ 0.90; I² = 52.5%). A linear dose-response relation between serum TC levels and overall cancer risk was found (p = .004 for Wald test; I² = 49.6%), and the pooled RR was 0.92 (95% CI: 0.89 ∼ 0.94) for 3 mmol/L, 0.86 (95% CI: 0.81 ∼ 0.90) for 5 mmol/L, 0.80 (95% CI: 0.74 ∼ 0.87) for 7 mmol/L. Our dose-response meta-analysis of 12 prospective studies indicated that higher serum TC levels were significantly associated with reduced cancer risk.