Melanoma is the most aggressive type of skin cancer and is associated with environmental and genetic risk factors. It originates in melanocytes, the pigment-producing cells. Single nucleotide ...polymorphisms (SNPs) in pigmentation genes have been described in melanoma risk modulation, but knowledge in the field is still limited.
In a case-control approach (107 cases and 119 controls), we investigated the effect of four pigmentation gene SNPs (TYR rs1126809, HERC2 rs1129038, SLC24A5 rs1426654, and SLC45A2 rs16891982) on melanoma risk in individuals from southern Brazil using a multivariate logistic regression model and multifactor dimensionality reduction (MDR) analysis.
Two SNPs were associated with an increased risk of melanoma in a dominant model: rs1129038AA and rs1426654AA OR = 2.094 (95% CI: 1.106-3.966), P = 2.3 10
and OR = 7.126 (95% CI: 1.873-27.110), P = 4.0 10
, respectively. SNP rs16891982CC was associated with a lower risk to melanoma development in a log-additive model when the allele C was inherited OR = 0.081 (95% CI: 0.008-0.782), P = 3 10
. In addition, MDR analysis showed that the combination of the rs1426654AA and rs16891982GG genotypes was associated with a higher risk for melanoma (P = 3 10
), with a redundant effect.
These results contribute to the current knowledge and indicate that epistatic interaction of these SNPs, with an additive or correlational effect, may be involved in modulating the risk of melanoma in individuals from a geographic region with a high incidence of the disease.
Abstract
Background
The influence of the novel human coronavirus disease (COVID‐19) pandemic on skin cancer characteristics in Latin America is still poorly elucidated.
Methods
This was a ...cross‐sectional study which included patients diagnosed with skin cancer (basal cell carcinoma BCC, cutaneous squamous cell carcinoma cSCC, and primary cutaneous melanoma cMM) during the first year of the COVID‐19 pandemic (from March 1, 2020, to February 28, 2021) and the preceding year at our institution. The total number of skin cancer diagnoses and surgeries, as well as their topography, clinicopathological staging at diagnosis, and treatment delay were compared between the two periods.
Results
There was a 31.8% reduction in skin cancer diagnoses during the first year of the COVID‐19 pandemic at our institution. There was an increase in the proportion of low‐risk cancers according to the NCCN guidelines for BCCs (40.8–49%,
P
< 0.001) and cSCCs (41.7–49.6%,
P
= 0.03), but there was no difference in the distribution of other staging systems for the three types of cancer. We also found a significant reduction in surgeries for BCCs (−57.6%,
P
< 0.001) and cSCCs (−44.7%,
P
< 0.001) but not for cMM.
Conclusions
The first year of the COVID‐19 pandemic was associated with reduced numbers of skin cancer diagnoses and surgeries at our institution. This study provides an assessment of skin cancer characteristics during the first year of the pandemic in the Latin American population.
Actinic keratoses are dysplastic proliferations of keratinocytes with potential for malignant transformation. Clinically, actinic keratoses present as macules, papules, or hyperkeratotic plaques with ...an erythematous background that occur on photoexposed areas. At initial stages, they may be better identified by palpation rather than by visual inspection. They may also be pigmented and show variable degrees of infiltration; when multiple they then constitute the so-called field cancerization. Their prevalence ranges from 11% to 60% in Caucasian individuals above 40 years. Ultraviolet radiation is the main factor involved in pathogenesis, but individual factors also play a role in the predisposing to lesions appearance. Diagnosis of lesions is based on clinical and dermoscopic examination, but in some situations histopathological analysis may be necessary. The risk of transformation into squamous cell carcinoma is the major concern regarding actinic keratoses. Therapeutic modalities for actinic keratoses include topical medications, and ablative and surgical methods; the best treatment option should always be individualized according to the patient.
The presence of myofibroblast differentiation has been proposed as an invading mechanism in basal cell carcinomas. However, small studies regarding α-smooth muscle actin positivity have led to ...conflicting results. This review of 100 cases examines the association between α-smooth muscle actin positivity on immunohistochemical studies and the clinical and histopathological characteristics of the tumor, including tumor size, thickness, subtype, topography, ulceration, 5-year recurrence rate, and age at diagnosis.
Summary
Spitzoid lesions represent a challenging and controversial group of tumours, in terms of clinical recognition, biological behaviour and management strategies. Although Spitz naevi are ...considered benign tumours, their clinical and dermoscopic morphological overlap with spitzoid melanoma renders the management of spitzoid lesions particularly difficult. The controversy deepens because of the existence of tumours that cannot be safely histopathologically diagnosed as naevi or melanomas (atypical Spitz tumours). The dual objective of the present study was to provide an updated classification on dermoscopy of Spitz naevi, and management recommendations of spitzoid‐looking lesions based on a consensus among experts in the field. After a detailed search of the literature for eligible studies, a data synthesis was performed from 15 studies on dermoscopy of Spitz naevi. Dermoscopically, Spitz naevi are typified by three main patterns: starburst pattern (51%), a pattern of regularly distributed dotted vessels (19%) and globular pattern with reticular depigmentation (17%). A consensus‐based algorithm for the management of spitzoid lesions is proposed. According to it, dermoscopically asymmetric lesions with spitzoid features (both flat/raised and nodular) should be excised to rule out melanoma. Dermoscopically symmetric spitzoid nodules should also be excised or closely monitored, irrespective of age, to rule out atypical Spitz tumours. Dermoscopically symmetric, flat spitzoid lesions should be managed according to the age of the patient. Finally, the histopathological diagnosis of atypical Spitz tumour should warrant wide excision but not a sentinel lymph‐node biopsy.
What's already known about this topic?
Spitzoid lesions represent a challenging and controversial group of tumours, in terms of clinical recognition, biological behaviour and management strategies.
Dermoscopy improves the clinical recognition of Spitz naevi, but a morphological overlap between Spitz naevi and spitzoid melanoma does exist.
Histopathologically, some tumours cannot be safely diagnosed either as Spitz naevi or as melanomas.
These controversies result in a significant inconsistency of management of spitzoid tumours among clinicians.
What does this study add?
Three dermoscopic patterns may be considered as suggestive of a Spitz naevus: starburst pattern, regularly distributed dotted vessels and globular pattern with reticular depigmentation.
Dermoscopically asymmetric lesions with spitzoid features (both flat/raised and nodular) should be excised to rule out melanoma.
Dermoscopically symmetric spitzoid nodules should also be excised or closely monitored, irrespective of the age, to rule out atypical Spitz tumours.
Dermoscopically symmetric flat spitzoid lesions should be managed according to the age of the patient.
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Normally, activation of tropomyosin-related kinase (TRK) receptors by neurotrophins (NTs) stimulates intracellular pathways involved in cell survival and proliferation. Dysregulation of NT/TRK ...signaling may affect neoplasm prognosis. Data on NT and TRK expression in melanomas are limited, and it is unclear whether NT/TRK signaling pathways are involved in the origin and progression of this neoplasm.
We examined whether NT/TRK expression differs across different cutaneous melanoma grades and subtypes, and whether it is associated with melanoma prognosis and survival. A cross-sectional study was performed in which the expression of TrkA, TrkB, nerve growth factor (NGF), and brain-derived neurotrophic factor (BDNF) was analyzed by immunohistochemistry of 154 melanoma samples. We investigated NT/TRK expression associations with prognostic factors for melanoma, relapse-free survival (RFS), and overall survival (OS).
Of the 154 melanoma samples, 77 (55.4%) were TrkA immunopositive, 81 (58.3%) were TrkB immunopositive, 113 (81.3%) were BDNF immunopositive, and 104 (75.4%) were NGF immunopositive. We found NT/TRK expression associated strongly with several clinical prognostic factors, including the tumor-node-metastasis stage (p < 0.001), histological subtype (p < 0.001), and Clark level (p < 0.05), as well as with a worse OS (p < 0.05 for all, except TrkB) and RFS (p < 0.05 for all).
Our results show strong associations of NT/TRK expression with melanoma stage progression and a poor prognosis.
Actinic keratoses (AKs) are dysplastic proliferations of keratinocytes. Studies evaluating nonfacial dermatoscopic pattern of AKs are scarce.
This study aimed to evaluate the dermatoscopic patterns ...of AKs located in nonfacial sites and to compare their patterns with facial lesions.
Patients with concomitant facial and nonfacial AKs were recruited to participate and evaluated by clinical and dermatoscopic images of their AKs.
Sixty-eight patients were included in the study. A total of 258 nonfacial AKs and 68 facial AKs were analyzed. The most frequent nonfacial AK dermatoscopic structures were white opaque scales (97.3%) and erythema (57.4%). When analyzed in combination, white scales plus erythema were found in 55.4% of nonfacial AKs. Pigmented structures were observed in 22.5% nonfacial AKs. Homogeneous brown pigmentation was the most prevalent pigmented structure in nonfacial pigmented AK (pAK) (93.1%). There was a positive association between patients having concomitant pigmented facial and nonfacial AKs (p < .001).
The combinations of erythema and white opaque scales or yellow opaque scales and homogeneous pigmentation are suggestive, respectively of nonpigmented and pigmented nonfacial AKs. Pigmented AKs occur concomitantly in facial and nonfacial areas.