Basaloid follicular hamartomas in pediatric Basal Cell Nevus Syndrome: A diagnostic challenge

Basal Cell Nevus Syndrome (BCNS) is an autosomal dominant inherited disease caused by PTCH1 (9q22.3‐q31) germline mutations. Skin manifestations are mainly characterized by hyperkeratosis of the palms and soles, palmoplantar pits and a strong predisposition to develop multiple basal cell carcinomas (BCCs). Recently, it has been hypothesized that basaloid follicular hamartomas (BFH) could be included in BCNS skin features. We present three pediatric cases of GS with BCCs and BFHs. Clinical, dermoscopic and immunohistochemical tools are reported.

Unraveling the role of microRNA/isomiR network in multiple primary melanoma pathogenesis

Malignant cutaneous melanoma (CM) is a potentially lethal form of skin cancer whose worldwide incidence has been constantly increasing over the past decades. During their lifetime, about 8% of CM patients will develop multiple primary melanomas (MPMs), usually at a young age and within 3 years from the first tumor/diagnosis. With the aim of improving our knowledge on MPM biology and pathogenesis, we explored the miRNome of 24 single and multiple primary melanomas, including multiple tumors from the same patient, using a small RNA-sequencing approach. From a supervised analysis, 22 miRNAs were differentially expressed in MPM compared to single CM, including key miRNAs involved in epithelial-mesenchymal transition. The first and second melanoma from the same patient presented a different miRNA profile. Ten miRNAs, including miR-25-3p, 149-5p, 92b-3p, 211-5p, 125a-5p, 125b-5p, 205-5p, 200b-3p, 21-5p, and 146a-5p, were further validated in 47 single and multiple melanoma samples. Pathway enrichment analysis of miRNA target genes revealed a more differentiated and less invasive status of MPMs compared to CMs. Bioinformatic analyses at the miRNA isoform (isomiR) level detected a panel of highly expressed isomiRs belonging to miRNA families implicated in human tumorigenesis, including miR-200, miR-30, and miR-10 family. Moreover, we identified hsa-miR-125a-5p|0|-2 isoform as tenfold over-represented in melanoma than the canonical form and differentially expressed in MPMs arising in the same patient. Target prediction analysis revealed that the miRNA shortening could change the pattern of target gene regulation, specifically in genes implicated in cell adhesion and neuronal differentiation. Overall, we provided a putative and comprehensive characterization of the miRNA/isomiR regulatory network of MPMs, highlighting mechanisms of tumor development and molecular features differentiating this subtype from single melanomas.

BRAF-mutated malignant melanoma with chondrosarcomatous differentiation in inguinal nodal metastasis

We report the case of a young woman who developed metastatic melanoma in the inguinal nodal region, which acquired chondrosarcomatous differentiation and preserved the BRAF mutation found in the primary tumor. The patient was treated with a BRAF/MEK inhibitor combination therapy (dabrafenib/trametinib), which was demonstrated to be effective and well-tolerated.

Oral Manifestations in Melanoma Patients Treated with Target or Immunomodulatory Therapies

BACKGROUND

BRAF (v-raf murine sarcoma viral oncogene homolog B1) and MEK (mitogen activated protein kinase) inhibitors, as well as immunotherapy against cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death 1 (PD-1) receptor and its ligand (PD-L1), have shown good results in improving the disease-free survival of patients with metastatic melanoma (MM). The aim of this review is to summarize the main oral adverse events (oAEs) occurring in patients undergoing target or immunotherapy. We proposed two separate sections: oAEs during the treatment with (1) target therapies with BRAF and MEK inhibitors and tyrosine kinase inhibitors (gingival hyperplasia, pigmentation disorders, squamo-proliferative lesions) and (2) immunotherapies with CTLA-4 or PD1 inhibitors (lichenoid reactions, immuno-bullous reactions, xerostomia and other reactions). Adverse events frequently include oAEs, although these are often misdiagnosed and under-reported. Indeed, the oral cavity is not routinely evaluated during clinical practice. The symptomatology related to oAEs is significant since it may represent the first manifestation of a severe systemic reaction, possibly leading to difficulties in nutrition with a consequent impact on patients' quality of life. A careful examination of the oral cavity is recommended during the evaluation of oncologic patients in order to promptly detect the onset of new manifestations.

Diagnosis of Melanonychia

Melanonychia has many causes and can involve one or several fingernails or toenails, and may occur at any age. Dermoscopy is used routinely in the evaluation of a pigmented nail. If pigmentation is caused by melanin produced by nail matrix, identify whether the pigmentation is caused by an activation or proliferation of nail melanocytes. When melanocytic proliferation is suspected, biopsy with histopathologic examination is the gold standard for diagnosis and is recommended when a longitudinal melanonychia occurs in an adult and is localized in a single digit, in the absence of local or systemic causes that may explain its onset.

Cutaneous and Mucosal Melanomas of Uncommon Sites: Where Do We Stand Now?

Melanomas arising at uncommon sites include a group of lesions related to unusual localizations in specific ethnic groups. The rarity of the disease often represents a limit to the participation of patients in specific trials. However, this peculiar genetic scenario has important therapeutic implications regarding new oncologic therapies. The aim of this article is to review the clinical features, somatic alterations and therapeutic options for melanomas of uncommon sites. They can be classified as cutaneous and mucosal lesions affecting the nail apparatus, palms/soles, oral mucosa, genital area and scalp. The prognosis may be worse compared to melanomas of other districts, and a prompt diagnosis may dramatically influence the outcome. Dermatologists and oncologists should therefore distinguish this melanoma subgroup in terms of surgical intervention and medical treatment. Due to the lack of mutations in genes usually found in cutaneous melanomas, the discovery of novel targets is required to develop new strategies and to change the prognosis of non-responders or wild-type patients.

Eruptive Cherry Angiomas and Skin Melanoma: Further Insights into an Intriguing Association

BACKGROUND

Some risk factors for malignant melanoma (MM) are recognized.

OBJECTIVE

To compare the strength of association between MM and eruptive cherry angiomas (CAs) with that of other well-known associations.

METHODS

This cross-sectional study included all subjects referred to the Outpatient Dermatology-Oncology and Dermoscopy Units of the Universities of Ferrara and Bologna, Italy, over a 5-month period and submitted to total body skin examination. We recorded: age, sex, cutaneous and non-cutaneous malignancies, presence of CAs, arbitrarily considered as "eruptive" when >10, >40 common melanocytic naevi or >2 clinically atypical naevi. The strength of association between the possible risk factors and MM was calculated by odds ratio in both the whole population and age quartiles. Variables associated with MM were included in multiple logistic regression analysis.

RESULTS

1,190 subjects were included; 615 had malignant skin tumours, 462 MM, 85 extracutaneous tumours. Five hundred and eighty-seven subjects had eruptive CAs, 485 subjects >40 melanocytic naevi and 368 more than 2 atypical melanocytic naevi. Eruptive CAs, especially in subjects younger than 70, and >2 atypical melanocytic naevi, mostly in subjects older than 50, were significantly associated with MM. The strength of these 2 associations was similar. The presence of >40 melanocytic naevi was not associated with MM.

CONCLUSIONS

These findings confirmed an association between MM and eruptive CAs, which was as strong as the one between MM and >2 atypical melanocytic naevi. CAs seem an intriguing model of interaction between heterogeneous variables, like immunocompetence, stimuli inducing endothelial cell proliferation, and oncogenesis, which deserves further investigation.

Latest Evidence Regarding the Effects of Photosensitive Drugs on the Skin: Pathogenetic Mechanisms and Clinical Manifestations

Photosensitivity induced by drugs is a widely experienced problem, concerning both molecule design and clinical practice. Indeed, photo-induced cutaneous eruptions represent one of the most common drug adverse events and are frequently an important issue to consider in the therapeutic management of patients. Phototoxicity and photoallergy are the two different pathogenic mechanisms involved in photosensitization. Related cutaneous manifestations are heterogeneous, depending on the culprit drug and subject susceptibility. Here we report an updated review of the literature with respect to pathogenic mechanisms of photosensitivity, clinical manifestations, patient management, and prediction and evaluation of drug-induced photosensitivity. We present and discuss principal groups of photosensitizing drugs (antimicrobials, nonsteroidal anti-inflammatory drugs, anti-hypertensives, anti-arrhythmics, cholesterol, and glycemia-lowering agents, psychotropic drugs, chemotherapeutics, etc.) and their main damage mechanisms according to recent evidence. The link between the drug and the cutaneous manifestation is not always clear; more investigations would be helpful to better predict drug photosensitizing potential, prevent and manage cutaneous adverse events and find the most appropriate alternative therapeutic strategy.

Folliculotropism in head and neck lentigo maligna and lentigo maligna melanoma

BACKGROUND

Lentigo maligna (LM) and lentigo maligna-melanoma (LMM) are histotypes of melanoma arising in skin with cumulative solar radiation damage. The extension of atypical melanocytes to the hair follicle (folliculotropism) is a histopathological feature of LM/LMM. Its role has not been totally clarified, but it may be correlated to treatment response in LM or to progression in LMM.

OBJECTIVE

This retrospective, multicentric study aims to identify dermatoscopic features associated with folliculotropism in LMs/LMMs.

PATIENTS AND METHODS

We analyzed cases of head and neck LMs/LMMs diagnosed between 2005-2014 at Melanoma Units, University of Bologna/Modena/Florence/Siena (Italy), Nice (France): 25 LMs and 73 LMMs were included.

RESULTS

Grey circles (44 %) indicated an isthmic/bulb level of involvement, which were completely absent in the infundibular LM lesions (P = 0.041). In the group of LMMs, light/dark brown pseudonetwork and light brown structureless areas were an indicator of diffuse distribution of malignant melanocytes in the follicular units (P < 0.001 and P = 0.001, respectively), while grey circles indicated focal or diffuse distribution (P < 0.001).

CONCLUSIONS

A better understanding of the extension of malignant melanocytes is helpful, aiding clinicians in their decision to perform a radical excision or obtaining a biopsy in the most invasive area of the lesion, which includes potential folliculotropism.

Melanomas of the scalp: is hair coverage preventing early diagnosis?

BACKGROUND

Scalp melanomas are usually thicker and show worse prognosis than other sites and other head and neck melanomas. One hypothesis to explain this aggressive behavior could be diagnosis delay attributed to hair concealment of lesions.

METHODS

Primary melanomas of the scalp diagnosed over two decades at four reference centers in Australia and Italy were included. Hair coverage and visibility of the lesions were assessed on preoperative photographic documentation by two investigators and correlated with some prognostic factors (Breslow thickness, mitotic rate, and ulceration). Patients records and pathology reports provided clinical and histological data.

RESULTS

The majority of 113 melanomas included were located on easily visible areas of the scalp - hairless scalp (49%) or hairline (15%). The remaining ones (36%), considered to be hair-covered, showed more frequently thinning of hair (63%) than a dense hair coverage (37%). Melanomas of "hairy scalps" were more frequently invasive (81%) and had higher median Breslow (0.8 ± 1.3 mm) than those arising on bald scalps or areas with thinning of hair (43%; 0 ± 0.6 mm), P = 0.004. However, when considering only the invasive cases (n = 55), Breslow thickness and mitotic rate were not statistically different between concealed and easily visible areas. Melanomas detected by a doctor were thinner than those first noticed by the patient, relatives, or a hairdresser (P < 0.001).

CONCLUSIONS

Most scalp melanomas arose on easily visible areas, which are more prone to ultraviolet damage. Hair-covered ones, despite rare, could be overlooked during examination. Proactive screening of the scalp area should be encouraged.

Cauliflower-like exophytic mass on the skin: polypoid melanoma. Clinical, dermoscopic, and histologic features

Polypoid melanoma is a variant of nodular melanoma, whose poor prognosis depends on its thickness and the presence of ulceration at the time of diagnosis. The authors report two cases of polypoid melanoma, presenting as broad, cauliflower-like, polypoid masses. Dermoscopy was characterized by a multicolored pattern, atypical polymorphic vessels, and the fiber sign. Clinical and dermoscopic features can help to diagnose polypoid melanoma and exclude other possible differential diagnoses. However, histology remains mandatory to confirm the diagnostic suspicion.