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

Expression of mast cell tryptase and immunoglobulin E is increased in cutaneous photodamage: implications for carcinogenesis

Purpose: Mast cells, their serine proteinase tryptase, and immunoglobulin E (IgE) can be involved in cutaneous carcinogenesis.Materials and methods: To study the association of tryptase+ and IgE+ cells with photodamage and skin cancers 385 adult patients (201 males, 184 females, 75 with immunosuppression) at risk of any type of skin cancer were examined. Skin biopsies were taken from the sun-protected medial arm and from the photodamaged dorsal forearm skin followed by immunohistochemical staining for tryptase and IgE.Results: The results show that tryptase+ and IgE+ cells are significantly higher in number in the photodamaged than sun-protected skin, both in immunocompetent and -compromised subjects, and there is a strong correlation between tryptase+ and IgE+ cells. The numbers of forearm tryptase+ and especially IgE+ cells associated significantly with the forearm photodamage severity. In the logistic regression analysis, the forearm to upper arm ratio of IgE+ cells produced a univariate odds ratio of 1.521 (p = .010) and a multivariate one of 3.875 (p = .047) for the history of squamous cell carcinoma. The serum level of total IgE correlated significantly to the IgE to tryptase ratio in both skin sites.Conclusions: Therefore, IgE+ mast cells participate in photodamage and carcinogenesis, though it is unclear whether they are tumor-protective or -causative.

Spectrum of malignant and premalignant skin lesions in 505 adult subjects at risk of skin cancers

Patients at risk of skin cancers can develop varying types of cutaneous malignancies. However, some subjects may develop only one type of lesion. In this cross-sectional study, the spectrum of premalignant (PM) and malignant skin lesions and their risk factors were studied. Therefore, 505 adult subjects (aged 21-79 years, 256 males and 249 females, 96 with immunosuppression) at risk of any type of skin cancer were examined for cutaneous malignancies, nevi, actinic keratoses, photodamage, and possible risk factors. First, 12 different groups were identified with a varying set of PM and/or malignant skin lesions. Next, 5 larger groups were formed from them: basal cell carcinoma (BCC) only, malignant melanoma (MM) only, squamous cell carcinoma (SCC) and/or PM, BCC + SCC and/or PM, and MM + keratinocyte carcinoma (KC) and/or PM. The groups with BCC or MM only were younger and showed less photodamage than the mixed groups, while SCC/PM showed similarity with them. In logistic regression analyses, the platelet-to-lymphocyte ratio was associated with an increased risk of concomitant KC (OR 1.028, p = 0.023) or SCC/PM (OR 1.009, p = 0.047) in subjects with MM or BCC, respectively. Actinic keratoses produced ORs 0.246-0.252 (p = 0.008-0.020) for BCC in subjects with SCC/PM. Interestingly, atypical mole syndrome decreased the risk of SCC/PM in subjects with BCC (OR 0.092, p = 0.001). Advanced age was a significant risk factor for an additional type of lesion in all 3 comparisons (ORs 1.088-1.388, p = 0.001). In conclusion, even though there are numerous patients with only one lesion type, advancing age may determine the final lesion multiplicity.

Melanomas and mast cells: an ambiguous relationship

Mast cells (MCs) accumulate in a broad range of tumors, including melanomas. While MCs are potent initiators of immunity in infection, and in allergic inflammation, the function of MCs in anti-melanoma immunity is unclear. MCs have the potential to release tumoricidal cytokines and proteases, to activate antigen-presenting cells and to promote anti-tumor adaptive immunity. However, within the immunosuppressive tumor microenvironment (TME), MC activation may promote angiogenesis and contribute to tumor growth. In this review, the relationship between MCs and melanomas is discussed with a focus on the impact of the TME on MC activation.

Elevated IgE Levels-An Allergy or an Underlying Inborn Error of Immunity in Children with Recurrent Infections?

Elevated immunoglobulin E (IgE) is a hallmark of allergic diseases. However, high IgE levels also occur in a number of other infectious and noninfectious diseases. In most cases, elevated IgE levels indicate allergy, eczema, or chronic skin infection. Very high IgE levels are not uncommon in patients with active eczema but more often indicate monogenic atopic disorder or inborn errors of immunity with an atopic phenotype. We conducted a retrospective study of 385 children with suspected immune deficiency referred to the clinic over a 9-year period. Measurement of IgE, IgG, IgA, IgM, and IgG subclasses in blood samples revealed that nearly one-third of the patients had elevated serum IgE levels. Most of the cases with elevated IgE were children with underlying atopy-mainly atopic dermatitis and, to a lesser extent, bronchial asthma-whereas 40.12% (37 children) had no atopy at all. In the most severe cases (with extremely elevated IgE or severe dermatitis), we confirmed genetic mutations for underlying immunodeficiency. Our results indicate that allergic phenotype should not be underestimated and that children with more severe allergic disease should be evaluated for an underlying inborn error of immunity. If inborn error of immunity (IEI) is suspected, a comprehensive immunologic evaluation is required. Genetic testing helps identify the specific genetic abnormality, which provides important insight into the immunopathogenesis of the disease and accurate determination of optimal therapy.