The lack of a relationship between atopic dermatitis and nonmelanoma skin cancers

Incidence and profile of skin cancers in patients following ultraviolet phototherapy without psoralens: A retrospective cohort study

BACKGROUND

Psoralen + ultraviolet-A (PUVA) is associated with photocarcinogenesis. However, carcinogenic risk with other ultraviolet phototherapies remains unclear.

OBJECTIVE

Evaluate whether phototherapy without psoralens increases skin cancer risk.

METHODS

Retrospective cohort study of patients treated at a teaching-hospital phototherapy center (1977-2018). Skin cancer records were validated against pathology reports. Age-standardized incidence rates (ASIRs) of skin cancer were evaluated for gender, skin phototype, diagnosis, ultraviolet modality, anatomical site; and compared to provincial population incidence rates (2003).

RESULTS

In total, 3506 patients treated with broadband-ultraviolet-B, narrowband-UVB and/or combined UVAB were assessed with a mean follow-up of 7.3 years. Majority of patients had psoriasis (60.9%) or eczema (26.4%). Median number of treatments was 43 (1-3598). Overall, 170 skin cancers (17 melanoma, 33 squamous cell carcinoma and 120 basal cell carcinoma) occurred in 79 patients. Patient-based and tumor-based ASIR of skin cancer was 149 (95% CI: 112-187)/100,000 and 264 (219-309)/100,000 person-years, respectively. There was no significant difference between tumor-based ASIRs for melanoma, squamous cell carcinoma, and basal cell carcinoma compared to the general population; or in phototherapy patients with-psoriasis or eczema; or immunosuppressants. No cumulative dose-response correlation between UVB and skin cancer was seen.

LIMITATIONS

Treatment and follow-up duration.

CONCLUSION

No increased risk of melanoma and keratinocyte cancer was found with phototherapy.

Patients with a history of atopy have fewer cutaneous melanomas than those without atopy: a cross-sectional study in 496 patients at risk of skin cancers

The connection between atopy and skin cancers may be related to the stimulation of protective immune response, for example, through autoreactive immunoglobulin-E (IgE), or to the predisposition to carcinogenesis through chronic inflammation. The aim of this study was to investigate whether a past or present atopic disorder is associated with cutaneous photodamage, pigment cell nevi and skin cancers. For this, adult subjects at risk of any type of skin cancer (aged 21-79 years, 250 males, 246 females, 94 with immunosuppression) were examined for past or present malignancies in skin and extracutaneous site (ECS), photodamage, nevi, past or present atopic disorder in skin or mucus membranes, and possible other cancer-related factors. No association between atopy and photodamage, keratinocyte carcinomas or nevus count was found. Instead, there were fewer subjects with melanoma in 171 atopic (14.6%) than in 325 nonatopic subjects (22.2%) (P = 0.044), and the investigator-estimated risk class of skin cancers was lower in atopic than nonatopic subjects. In all subjects, the multivariate odds ratio (OR) for melanoma was 0.583 (P = 0.046; 95% confidence interval, 0.343-0.990) in atopic subjects, but in immunocompetent subjects, the reduced risk was confined to mucus membrane atopy (OR, 0.417; P = 0.020). Also, there were fewer subjects with malignancy in ECS in atopic (8.8%) than nonatopic subjects (15.7%) (P = 0.031). No association between serum total IgE and skin cancers, photodamage, nevi or malignancies in ECS was found. In conclusion, the atopy, especially mucus membrane atopy, is associated with lower percentages of subjects with a history of melanoma.

Evaluation of risk in chronic cutaneous inflammatory conditions for malignant transformation

Skin carcinomas are the most common form of cancer, and every year thousands of people die from skin cancer-related malignancies. Chronic inflammation is linked to the development and progression of cancer in multiple organ systems - about 20% of all human cancers are a result of chronic inflammation - skin included. While acute inflammation under normal circumstances is a mechanism for host defence and tissue regeneration following insult by trauma or infection by pathogens, over the long term it can drive oncogenic transformation of epithelial cells and promote cancer development, growth and metastasis. Therefore, inflammatory conditions may put individuals at a higher risk to developing skin malignancies. Many skin conditions are characterized by chronic inflammatory processes. These conditions may be particularly susceptible to malignant transformation and predispose patients to develop skin malignancies. As more pathophysiology of chronic inflammatory skin conditions is unveiled, we find that many of these conditions are characterized by immune dysregulation and signalling that result in chronic activation and upregulation of pro-inflammatory chemokines and cytokines, leading to downstream processes that further exacerbate inflammatory processes and cause abnormal cell growth and apoptosis. Here, we review the major chronic cutaneous inflammatory diseases that may have an increased risk of skin malignancies, including atopic dermatitis, psoriasis, discoid lupus erythematosus, lichen planus, hidradenitis suppurativa, prurigo nodularis, lichen sclerosus, systemic sclerosis and morphea, chronic leg ulcers, seborrheic keratoses and basal cell carcinoma. We evaluate the evidence for increased incidence and prevalence, the risk factors associated, the populations at heightened risk and the best management practices.

Noncutaneous and Cutaneous Cancer Risk in Patients With Atopic Dermatitis: A Systematic Review and Meta-analysis

Importance

Impaired skin barrier and aberrant immune function in atopic dermatitis (AD) may alter immune response to malignant cancer. Conflicting data exist on the risk of cancer in patients with AD.

Objective

To assess the risk of noncutaneous and cutaneous cancers in patients with AD compared with the general population without AD.

Data Sources

Studies identified from searches of MEDLINE and Embase that were published from 1946 and 1980, respectively, to January 3, 2019. The following search terms were used: [(exp NEOPLASMS/ OR neoplas*.tw. OR tumo*.tw. OR cancer*.tw. OR malignanc*.tw.) AND (exp Dermatitis, Atopic/ OR (atopic adj1 (dermatit* or neurodermatit*)).tw. OR eczema.tw. OR disseminated OR neurodermatit*.tw.)].

Study Selection

Included were observational studies (cohort and case-control designs) reporting a risk estimate for cancer in patients with AD compared with a control group (general population or patients without AD).

Data Extraction and Synthesis

Two independent reviewers extracted data and assessed the risk of bias using the Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) assessment tool, modified for observational exposure studies. Data were pooled using a random-effects model and expressed as standardized incidence ratios (SIRs) or odds ratios (ORs) with 95% CIs. Heterogeneity was assessed using the Cochrane Q statistic and the I2 statistic.

Main Outcomes and Measures

The main outcome of the study was risk of cancer measured by SIRs or ORs.

Results

This systematic review and meta-analysis included 8 population-based cohort studies (n = 5 726 692 participants) and 48 case-control studies (n = 114 136 participants). Among cohort studies, a statistically significant association was found between AD and keratinocyte carcinoma (5 studies; pooled SIR, 1.46; 95% CI, 1.20-1.77) as well as cancers of the kidney (2 studies; pooled SIR, 1.86; 95% CI, 1.14-3.04), central nervous system (2 studies; pooled SIR, 1.81; 95% CI, 1.22-2.70), and pancreas (1 study; SIR, 1.90; 95% CI, 1.03-3.50). Among 48 case-control studies, pooled effects showed patients with AD had statistically significantly lower odds of central nervous system cancers (15 studies; pooled OR, 0.76; 95% CI, 0.70-0.82) and pancreatic cancer (5 studies; pooled OR, 0.81; 95% CI, 0.66-0.98), contrary to the higher incidence found in cohort studies. Case-control studies also demonstrated lower odds of lung and respiratory system cancers (4 studies; pooled OR, 0.61; 95% CI, 0.45-0.82). No evidence of association was found between AD and other cancer types, including melanoma. There was substantial heterogeneity between studies for many other cancers, which precluded pooling of data, and there was moderate to serious risk of bias among included studies.

Conclusions and Relevance

Observational evidence suggests potential associations between AD and increased risk of keratinocyte carcinoma and kidney cancer as well as lower odds of lung and respiratory system cancers. Further research is needed to address the heterogeneity and limitations of current evidence and to better understand the mechanisms underlying a possible association between AD and cancer risk.

Current status and perspectives regarding the association between allergic disorders and cancer

While activation of immune system may lead to a lower risk of some diseases, it has been shown that a history of atopic allergic disorders such as asthma, hay fever, eczema, and food allergies could be related to several types of cancer. However, the evidence is not entirely conclusive. Two proposals suggest a possible mechanism for the association between allergic disorders and cancers: immune surveillance and the antigenic stimulation. The association of allergy and cancer may vary by cancer site and the type of exposure. The aim of current review was to summarize the current knowledge of the association between allergic diseases and the risk of cancers with particular emphasis on case-controls and cohort studies to estimate the cancer risk associated with allergy.

Long-term topical corticosteroid use and risk of skin cancer: a systematic review

OBJECTIVE

The objective of this systematic review was to synthesize available research evidence to determine the risk of skin cancer in patients with long-term use of topical corticosteroids (TCS).

INTRODUCTION

Topical corticosteroids are one of the most commonly prescribed medicines in dermatology and the mainstay of the treatment of atopic dermatitis and other skin conditions such as psoriasis. They are often required for months or years to control the disease and ultimately restore patients' quality of life. In some patients, TCS may have a local immunosuppressive effect and theoretically increase the risk of skin cancer, whilst on the other hand TCS may decrease the risk of skin cancer in patients where TCS are used to treat inflammatory skin disease. To date, no systematic review has been performed to collate evidence on the effect of long-term TCS use on the risk of skin cancer.

INCLUSION CRITERIA

This review considered studies that included people of all ages, genders and ethnicities, including HIV and transplant participants or participants with genetic diseases (for example, Gorlin-Goltz syndrome) This review considered studies that evaluated long-term use of topical corticosteroids. "Long-term" was defined as using TCS more than once a week for a month or longer. The review included cohort, cross-sectional and case-control observational studies exploring the association between the stated intervention and outcomes. The primary outcome measures of interest were: non-melanoma skin cancer (keratinocyte carcinoma), cutaneous squamous cell carcinoma (cSSC), basal cell carcinoma (BCC) or melanoma skin cancer. Genital and oral skin cancers are considered to be slightly different so we did not include them in this review.

METHODS

We performed a comprehensive search of MEDLINE, Embase and LILACS on November 9, 2017 to identify observational epidemiological studies assessing the association between long-term TCS use and skin cancer. We also searched EThOS at the British Library and three drug safety databases to identify unpublished work. The titles, abstracts and full text identified from the search were assessed independently by two authors against pre-specified inclusion/exclusion criteria. Methodological quality was not assessed as no articles were found which met the inclusion criteria. Data extraction was not possible as no articles were found which met the inclusion criteria. It was not possible to complete data synthesis as no articles were found which met the inclusion criteria.

RESULTS

A total of 1703 potentially relevant studies were identified following a comprehensive electronic search. After abstract and title screening, 51 full texts were assessed for eligibility criteria. Of these, no study met the inclusion criteria. No additional records were identified from searching unpublished literature.

CONCLUSIONS

We did not find any studies that could help us establish if long-term TCS use is associated with skin cancer. Future research using primary care databases might give a better understanding regarding long-term use of TCS and skin cancer.

Filaggrin loss-of-function mutations, atopic dermatitis and risk of actinic keratosis: results from two cross-sectional studies

BACKGROUND

Common loss-of-function mutations in filaggrin gene (FLG) represent a strong genetic risk factor for atopic dermatitis (AD). Homozygous mutation carriers typically display ichthyosis vulgaris (IV) and many have concomitant AD. Previously, homozygous, but not heterozygous, filaggrin gene mutations have been associated with squamous cell carcinomas.

OBJECTIVE

The first objective was to examine the association between FLG mutations and actinic keratosis (AK). The second objective was to investigate the occurrence of AK in patients with IV and AD, respectively.

METHODS

FLG mutation status in patients with AK was compared with controls from the general population. Furthermore, based on nationwide data from Danish registers, we compared the risk of AK in patients with IV, AD and psoriasis, respectively.

RESULTS

The prevalence of homozygous FLG mutations was significantly higher in the AK group (n = 4, 0.8%) in comparison with the control group (n = 18, 0.2%), whereas the prevalence of heterozygous FLG mutations was lower. In hospital registry data, patients with AD exhibited an increased risk of AK than did psoriasis controls (adjusted OR 1.46; [95% CI 1.12-1.90]), whereas no difference in risk was observed between patients with IV and AD.

CONCLUSIONS

This study indicates an increased susceptibility to AK in individuals with homozygous, but not heterozygous, FLG mutations and in patients with AD compared to psoriasis. Whether a reduction or absence of epidermal filaggrin could contribute to the susceptibility to AK in patients with IV and AD is unknown and additional research is needed to further explore this relationship.

Comorbidities of Atopic Dermatitis: Beyond Rhinitis and Asthma

PURPOSE OF REVIEW

In this review article, we summarize the current evidence about atopic dermatitis (AD)-associated comorbidities, beyond the traditional atopic and allergic conditions.

RECENT FINDINGS

Patients with AD may have an increased risk of cardiovascular diseases, certain malignancies, autoimmune diseases, and neuropsychiatric diseases. The causes of these associations are likely multifactorial and may include genetic predispositions, systemic low-grade inflammation, environmental exposures, medication, and lifestyle and behavioral risk factors. There appears to be geographical variations in prevalence of comorbidities in patients with AD, indicating that differences in ethnicity and lifestyle factors may significantly influence the risk of certain comorbidities.

SUMMARY

The reported comorbidities in recent literature emphasize the burden of disease in patients with AD. Early appropriate AD therapy, in combination with reduction of risk factors, may help prevention of certain comorbidities. The reported observations may generate hypotheses for future investigations in underlying risk factors for AD-associated comorbidities.

Association between cancer and allergies

Background

The prevalence of allergies and the incidence of cancer are both increasing worldwide. It has been hypothesized that atopy may affect the risk of some cancers.

Methods

In this study, 1525 patients (754 women and 771 men with a mean age of 52.7 ± 11.9 years) with different types of cancer were examined for the presence of allergies. Allergies were confirmed based on retrospective analysis of allergy diagnostic procedures in patients previously diagnosed with cancer. All patients were also analyzed for bronchial asthma and allergic rhinitis according to relevant guidelines. A control group of patients without cancer diagnoses was used for comparison.

Results

Patients with cancer had significantly fewer IgE-mediated allergic diseases than the control population. For the oncological group compared to the non-cancer patients, the odds ratios (ORs) for allergic rhinitis, atopic dermatitis, and bronchial asthma were 0.67 (95 % CI 0.52–0.81), 0.89 (95 % CI 0.78–0.99), and 1.03 (95 % CI 0.91–1.13), respectively. The mean serum concentrations of total IgE were significantly lower in the study population of patients with cancer than in the patients in the control group (45.98 ± 14.9 vs. 83.2 ± 40.1 IU/l; p < 0.05). There were no significant correlations between the type of cancer diagnosed and the form of allergy.

Conclusion

Our results indicate that the overall incidence of allergies, particularly allergic rhinitis, was lower in patients with some types of cancer. Further studies are needed to confirm our findings.

History of allergy and atopic dermatitis in relation to squamous cell and Basal cell carcinoma of the skin

BACKGROUND

Little is known about whether history of allergies and atopy is related to the occurrence of keratinocyte cancers. Thus, we evaluated the association between history of allergies and atopy and the incidence of squamous cell carcinoma (SCC) and early onset basal cell carcinoma (BCC).

METHODS

As part of a population-based case-control study, interviews were conducted with 1,050 residents of New Hampshire (375 early onset BCC cases and 251 controls, 254 SCC cases and 432 controls). ORs of SCC and early onset BCC and history of allergy and atopic dermatitis were computed using logistic regression, while controlling for potential confounding factors.

RESULTS

An overall inverse association was observed between a history of allergy and early onset BCC [OR, 0.61; 95% confidence interval (CI), 0.38-0.97] but not SCC (OR, 1.18; 95% CI, 0.78-1.79). Among women, we found reduced ORs of both early onset BCC and of SCC in relation to allergy history (early onset BCC OR, 0.53; 95% CI, 0.31-0.92 and SCC OR, 0.59; 95% CI, 0.29-1.19). Among men, we observed no clear association with early onset BCC (OR, 0.87; 95% CI, 0.39-1.99) and an increased risk of SCC (OR, 1.58; 95% CI, 0.93-2.69).

CONCLUSION

Our findings suggest that allergies and atopy may influence risk of early onset BCC and SCC, and that effects may be gender specific.

IMPACT

A deeper understanding of the immune mechanisms underlying allergies and atopy may provide new routes of preventing keratinocyte cancers.

Association between common allergic symptoms and cancer in the NHANES III female cohort

BACKGROUND

Previous epidemiological studies have investigated the association between allergic symptoms and cancer occurrence. However, the role of allergy in cancer has been elusive, especially for the female population.

METHODS

We examined the relationship between cancer prevalence and common allergic symptoms of rhinoconjunctivitis (RC) and wheezing (WZ) among NHANES III female participants.

RESULTS

Among 4600 people, 36.3% (n = 1669) did not have any allergic symptoms (NO), while 47.6% (n = 2188) reported RC, and 16.2% (n = 743), WZ. The proportion of cancer among NO groups was 5.43% (91/1669), among RC group, 7.63% (167/2188), and among WZ group, 11.23% (83/743) (RC group- OR 1.44 with 95% CI 1.00-2.08; p = 0.05 while for WZ group- OR 2.20 with 95%CI 1.27-3.80; p = 0.01). After adjusting for all the possible confounding variables including age, smoking, or COPD, having symptoms of RC (AOR 1.49 with 95%CI 1.12-2.36; p = 0.01) or WC (AOR 2.08 with 95%CI 1.11-3.89; p = 0.02) demonstrated consistent strong association with cancer. Among nonsmokers (n = 2505, 54.5%) only symptoms of RC showed association with cancer (AOR 1.51 with 95%CI 1.00-2.28; p = 0.05). Among former or current smokers (n = 2094, 45.5%), only symptoms of WZ demonstrated association with cancer (AOR 2.38 with 95%CI 1.16-4.87; p = 0.02). Among different types of cancers, odds of having breast cancer among participants with symptoms of RC or WZ were approximately twice the odds of having breast cancer among participants without any of these symptoms. AOR for RC group was 1.89 with 95%CI 1.04-3.42 and p = 0.04 while AOR for WC group was 2.08 with 95%CI 0.90-4.78 and p = 0.08.

CONCLUSIONS

In summary, we found associations between common allergic symptoms like rhinitis/conjunctivitis and wheezing and prevalence of cancer, specifically between rhinitis/conjunctivitis and breast cancer that were not found in previous studies. Larger prospective studies are required to validate our findings.

Predictors of basal cell carcinoma in high-risk patients in the VATTC (VA Topical Tretinoin Chemoprevention) trial

Basal cell carcinoma (BCC) is the most common cancer in the United States today, and patients who have had one are likely to have multiple carcinomas over time. Predictors of new BCCs on the face and ears among those at very high risk have not been studied in detail. We sought to do so prospectively in the context of a 6-year trial. We found that the number of BCCs in the prior 5 years was the most important predictor. Age, sun sensitivity, occupational sun exposure before the age of 30 years (but not afterward), lower educational level, history of eczema, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and more sunscreen use in the week, but not the 6 months, before enrollment were also independent predictors, but sunburns, baseline sun exposure, and other sun-protective measures, other skin cancers, and actinic keratoses were not. None of the eczema patients had a history of topical calcineurin use. The cumulative risk of BCC was 55% at 5 years. These findings document the key risk factors in this very high-risk population, suggesting that the history of eczema may increase the risk in those at high risk and that early sun exposure is important even in this group, and underscoring the need for chemopreventive strategies.

Atopic dermatitis and risk of skin cancer: a Danish nationwide cohort study (1977-2006)

BACKGROUND

Recent data suggest a reduced risk of malignant melanoma (MM) among atopic dermatitis (AD) patients, but an increased risk of other skin cancers (including basal cell carcinoma [BCC] and squamous cell carcinoma [SCC]).

OBJECTIVE

We examined the association between AD and skin cancers in a large cohort study in Denmark from 1977 through 2006.

METHODS

Our cohort consisted of 31 330 AD patients recorded in the Danish National Patient Registry, including AD patients admitted to hospitals and specialized outpatient clinics. Linkage to the Danish Cancer Registry allowed ascertainment of skin cancers. We calculated standardized incidence ratios (SIRs) and associated 95% confidence intervals (CIs) by comparing the incidence rate of skin cancers among AD patients with that among the general Danish population.

RESULTS

The overall observed number of MM cases among AD patients was 12, with 21 expected, yielding a SIR of 0.59 (95% CI 0.30, 1.02), with the most pronounced protective effect among AD patients with more than 5 years of follow-up (SIR = 0.46; 95% CI 0.19, 0.95). The corresponding SIRs for BCC and SCC were increased among AD patients (1.41 [95% CI 1.07, 1.83] and 2.48 [95% CI 1.00, 5.11], respectively).

CONCLUSIONS

Our findings support an inverse association between AD and MM, but an increased risk of BCC and SCC among AD patients.

Risk of squamous cell carcinoma of the skin in relation to IgE: a nested case-control study

BACKGROUND

Individuals diagnosed with nonmelanoma skin cancer have a high risk of developing a second skin cancer diagnosis. We assessed whether a marker of immune function related to atopic allergy, IgE, was associated with diagnosis of subsequent squamous cell carcinoma (SCC) of the skin in patients with a previous skin cancer enrolled in a skin cancer prevention trial.

METHODS

One hundred twelve individuals who developed an SCC (cases) were compared with 227 controls who did not develop SCC over the same followup period, matched on age, sex, and study center. Total, respiratory, and food-specific IgE were measured in the baseline or year one (prior to diagnosis) sera samples for each subject.

RESULTS

IgE levels were higher in cases with SCC than controls (comparing the highest quartile with the lowest, OR(total IgE) = 1.44; 95% CI: 0.73-2.85; OR(respiratory IgE) = 2.43; 95% CI: 1.16-5.06; OR(food IgE) = 2.53; 95% CI: 1.19-5.35). The association between respiratory IgE and subsequent skin cancer was strongest among individuals with a tendency to sunburn (OR(respiratory IgE) = 3.82; 95% CI: 1.05-13.88) compared with those with a tendency to tan (OR(respiratory IgE) = 0.95; 95% CI: 0.20-4.76). Among 25 subjects with repeat IgE measurements taken over several years, IgE levels were remarkably stable (interclass coefficient = 0.90 for total IgE).

CONCLUSION

These results indicate that allergy or allergy-associated IgE may be indicative of an immune phenotype that enhances risk of SCC, possibly via immune-associate inflammatory mediators.

IMPACT

Our results indicate that controlling allergy and IgE levels may be a new avenue of skin cancer prevention in susceptible populations, and implicate immune mechanisms in skin carcinogenesis.

Evaluation of cancer risk related to atopic dermatitis and use of topical calcineurin inhibitors

Cases of lymphoma or cutaneous cancer have been observed following use of topical calcineurin inhibitors (TCIs), but it is unclear whether TCI use increases cancer risk. We used published literature to assess the extent to which atopic dermatitis (AD) or TCI use is associated with lymphoma, melanoma, basal cell carcinoma and squamous cell carcinoma. We searched the literature and summarized the results of all studies that provided data on the absolute or relative frequency of any malignancy among patients with AD or eczema or among patients using TCIs. The relative risk for all lymphoma in broad populations of AD or eczema ranged from 0·7 to 1·8. Available data on lymphoma following TCI use were inconsistent and insufficient to draw a conclusion about the causal role of TCIs. We found no evidence indicating that melanoma or nonmelanoma skin cancer is associated with TCI use. A bias analysis showed that cutaneous T-cell lymphomas initially misdiagnosed and treated as AD would lead to overestimation of the association between TCI use and lymphoma. However, there are only sparse data on specific malignancies among TCI-treated patients. The short duration of typical TCI exposure hinders conclusions about longer exposure. There is insufficient evidence in the epidemiological literature to infer whether TCIs do or do not cause malignancy.

Cancer risk in patients with allergic rhinitis, asthma and atopic dermatitis: a nationwide cohort study in Taiwan

It has long been a debate that whether atopy is a risk factor or protective factor for cancer. However, no large-scale study of different cancers in patients with atopic diseases has been conducted among Asians. Here, we conducted a nationwide study to evaluate the cancer risk in patients with allergic rhinitis (AR), asthma and atopic dermatitis (AD). Drawing on Taiwan's National Health Insurance Research Database, 225,315 patients with AR, 107,601 patients with asthma and 34,263 patients with AD without prior cancers were identified in the period from 1996 to 2008. The standard incidence ratio (SIR) of each cancer was calculated. Although the overall cancer risks in patients with atopic symptoms were not increased, the risks were slightly elevated in female patients with AR or asthma (SIR: 1.13 and 1.08, AR and asthma, respectively) and slightly decreased in males patients with AR. Those aged 20-39 years-old possessed the highest risk. A higher risk of developing brain cancer was found in patients with atopic diseases, and patient with AR or asthma also had an elevated risk of developing cancer of kidney and urinary bladder. In contrast, the risk of nonmelanoma skin cancer was lower in patients with AR and asthma. Compared to patients with only one atopic disease, those with more than one atopic disease had lower cancer risks. Our data suggests that the association between atopy and cancer is site-specific.

Incidence of cancer in the general population and in patients with or without atopic dermatitis in the U.K

BACKGROUND

Atopic dermatitis (AD) affects approximately 20% of children and 1-3% of adults in developed countries.

OBJECTIVE

To study the incidence of cancer in patients with AD in the U.K. general population.

METHODS

We conducted a follow-up study in the U.K. using The Health Improvement Network (THIN) database. We calculated the incidence rate (IR) of the first occurrence of overall cancer, lymphoma, melanoma and nonmelanoma skin cancer (NMSC) in the general population, in patients with AD and in individuals without AD. In addition we calculated the IR ratio (IRR) of overall cancer and subtypes of cancer in patients with AD vs. those without.

RESULTS

The study population included 4,518,131 patients [2,336,230 (51·7%) female]. There were 129,972 subjects [68,688 (52·8%) female] with a diagnosis of cancer (excluding NMSC). The IR (per 10,000 person-years) of cancer (excluding NMSC) was 42·41 [95% confidence interval (CI) 42·18-42·64]; of lymphoma 1·70 (95% CI 1·65-1·74); of skin melanoma 1·71 (95% CI 1·67-1·76) and of NMSC 11·76 (95% CI 11·64-11·88). The age- and sex-adjusted IRR for cancer (excluding NMSC) was 1·49 (95% CI 1·39-1·61); for lymphoma 2·21 (95% CI 1·65-2·98); for melanoma 1·74 (95% CI 1·25-2·41); and for NMSC 1·46 (95% CI 1·27-1·69).

CONCLUSIONS

Our results indicate an increased incidence of cancer overall as well as of specific cancer subtypes, including lymphoma, in patients with AD. Further studies are needed to disentangle the effects of treatment for AD from AD itself.

Lack of Association between Exposure to Topical Calcineurin Inhibitors and Skin Cancer in Adults

BACKGROUND

Two topical calcineurin inhibitors (TCI) are available for the treatment of atopic dermatitis and there has been concern that their use could be associated with an increased risk of nonmelanoma skin cancer (NMSC).

OBJECTIVE

To determine if TCI exposure is associated with an increased risk of NMSC in adults.

METHODS

A case-control study using a questionnaire mailed to 5,000 adults with dermatitis.

RESULTS

We received responses from 70.7% of those surveyed by mail. Overall, 25.7% reported exposure to TCI. TCI exposure was 14.4% for the cases and 30.7% for the controls. Our primary analysis was a comparison between those with NMSC and those without. The unadjusted odds ratio was 0.38 (0.31-0.47) and the adjusted (age, gender, previous NMSC, history of atopic dermatitis) was 0.54 (0.41-0.69). The odds ratio of association for NMSC decreased as the number of tubes used and the potency of the agent increased.

CONCLUSION

This early study shows that TCI use is not associated with an increased risk of NMSC in adults.

Non-melanoma skin cancer in patients with atopic dermatitis treated with topical tacrolimus

OBJECTIVE

To determine whether atopic dermatitis (AD) patients treated with tacrolimus ointment experienced an increased risk of non-melanoma skin cancer (NMSC).

METHODS

Data were collected from 9813 adult and paediatric patients with AD who applied 0.03% or 0.1% tacrolimus ointment twice daily and were examined every 3 months during the tacrolimus ointment development programme.

RESULTS

Thirteen adult patients were diagnosed with NMSC during the follow-up period. All patients with NMSC were white adults and 12 were over 40 years of age. Based on 1718 patient-years of tacrolimus ointment exposure in patients 40 years of age, the calculated incidence of NMSC did not suggest an increased risk of first NMSC over that of a similarly aged US cohort.

CONCLUSION

This study does not indicate an increased risk for the development of NMSC in patients with AD treated with tacrolimus ointment for a mean duration of 208 days with a maximum observation period of 1479 days.

Atopic dermatitis and cancer risk

BACKGROUND

Epidemiological studies have provided growing evidence of a link between atopy and cancer risk.

OBJECTIVES

To review the evidence from case-control studies and cohort studies on a possible association between atopic dermatitis (AD) and cancer risk, with particular attention to the case definition of AD.

METHODS

Studies with quantitative data on the association between AD (eczematous disease) and cancer risk were obtained from MEDLINE in combination with a review of cited references.

RESULTS

In 23 publications, AD was implicated in the risk of haematological [childhood leukaemia (n = 3), adult leukaemia (n = 3), non-Hodgkin lymphoma (NHL; n = 4) and different haematological cancers (n = 1)], pancreatic (n = 5), skin (n = 2) and brain malignancies (n = 5). The overall picture of the results of these studies shows that a history of AD may be associated with a decreased risk of pancreatic cancer, brain tumour and childhood leukaemia, although in most instances the findings were not statistically significant. No consistent associations were observed for skin cancer or NHL. The definition of AD had varying quality, and was imprecise in the majority of publications.

CONCLUSIONS

The findings of the epidemiological studies tend to support a lower risk of cancer among persons with a history of AD. Although a more careful definition of AD is needed, these epidemiological studies could provide an estimate of the background cancer risk in patients with AD when the long-term effects of treatments for AD are assessed.

Review of the potential photo-cocarcinogenicity of topical calcineurin inhibitors. Position statement of the European Dermatology Forum

Topical Calcineurin Inhibitors (TCIs) used for the treatment of atopic eczema modify the immune regulatory function of the skin and may have the potential to enhance immunosuppressive ultraviolet (UV) effects. Current recommendations on UV protection in eczema patients treated with PCIs are inconsistent and have given rise to uncertainty and anxiety in patients. Therefore, the European Dermatology Forum (EDF) developed a position statement which reviews critically the available data with regard to the problem, especially analysing and commenting the limitations of rodent models for the human situation. There is no conclusive evidence from rodent trials to indicate that long-term application of TCIs is photococarcinogenic. There is a need for further studies to investigate the validity of mouse models as well as long-term cohort studies in patients using TCIs. Available data suggest that long-term application of TCIs is safe, that there is no evidence of increased skin cancer risk and that it is ethical to treat patients with TCIs when indicated.

The risk of cancer among patients previously hospitalized for atopic dermatitis

In treatment of severe atopic dermatitis, drugs with carcinogenic potentials are used to manage the disease. We therefore analyzed whether patients having severe atopic eczema had an increased cancer risk. The study population included all individuals hospitalized in Denmark with a primary diagnosis of atopic dermatitis during 1977-1996. Follow-up was conducted in 1996 in the Danish Cancer Register. A total of 6275 persons were included. Among 2030 adult patients, an increased risk of cancer was observed, standard morbidity ratio (SMR)=1.5 (95% CI: 1.2-1.9). Half the excess cases of cancer was keratinocyte carcinomas of the skin diagnosed within the first 9 y of follow-up, SMR=2.4 (95% CI: 1.4-3.9). For men, SMR=2.7 (95%CI: 1.2-5.4). In conclusion, earlier hospitalized adult atopic dermatitis patients had an increased risk of cancer. Half the excess cases of cancer were keratinocyte carcinomas. This may be a result of a detection bias or due to the carcinogenic potentials of some of the therapies of severe atopic dermatitis.

Allergy and cancer

BACKGROUND

Conflicting results have provided support for two distinct and contradictory hypotheses: (i) allergy has a protective effect against cancer by enhanced immune surveillance, and (ii) allergy is associated with an increased risk of cancer by chronic immune stimulation. We therefore aimed us to perform a large epidemiological study with a defined allergic disease cohort.

METHODS

During the years 1988-2000, 70 136 patients tested for total serum immunoglobulin E (IgE) and 57 815 tested with Phadiatop for diagnosing allergic disease at Karolinska University Hospital, Stockholm, Sweden, were linked with the Swedish Cancer Registry for a virtually complete follow up with regard to cancer.

FINDINGS

The total number of observed cancers was normal in the total serum IgE-cohort; standardized incidence ratio (SIR) = 0.98 (95% CI: 0.92-1.04) and in the Phadiatop-cohort: SIR = 0.99 (0.92-1.06) independent of the level of IgE and positive or negative Phadiatop. Specific analysis was done for cancer of the lung, cervix, pancreas, lymphoma, and nonmelanoma skin cancer. None of these forms of cancer had increased risks.

INTERPRETATION

The study does not support the hypothesis that allergy has a protective effect against cancer, nor does it support an increased risk.