Eruptive melanocytic nevi in patients with renal allografts: report of 10 cases with dermoscopic findings

Eruptive melanocytic naevi following initiation of elexacaftor/ivacaftor/tezacaftor for cystic fibrosis

A 29 year old woman with cystic fibrosis (CF) presented to CF clinic following the sudden development of over 200 pigmented naevi located predominately on the trunk and limbs 3 months after commencing elexacaftor/tezacaftor/ivacaftor, a novel triple-therapy CFTR modulator therapy for CF. Skin biopsy confirmed benign naevi and the clinical presentation was consistent with eruptive melanocytic naevi. Elexacaftor/tezacaftor/ivacaftor received marketing authorisation in August 2020 and this is the first report of associated naevi. The individual described here remains clinically well, and continues on elexacaftor/tezacaftor/ivacaftor with dermatology follow-up.

Regulatory T Cells Play an Important Role in the Prevention of Murine Melanocytic Nevi and Melanomas

Melanocytic nevi are benign proliferations of pigment cells that can occasionally develop into melanomas. There is a significant correlation between increased nevus numbers and melanoma development. Our previous reports revealed that 7,12-dimethylbenz(a)anthracene (DMBA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) induced dysplastic nevi in C3H/HeN mice, with a potential to transform into melanomas. To understand the immune mechanisms behind this transformation, we applied increasing DMBA doses followed by TPA to the skin of C3H/HeN mice. We observed that increased doses of DMBA correlated well with increased numbers of nevi. The increased DMBA dose induced diminished immune responses and promoted the expansion of regulatory T cells (Treg) that resulted in increased IL10 and reduced IFNγ levels. Mice with increased nevus numbers had loss of p16 expression. These mice had increased migration of melanocytic cells to lymph nodes (LN) and a greater percent of LNs produced immortalized melanocytic cell lines. DMBA-induced immunosuppression was lost in CD4-knockout (KO) mice. Lymphocytes in the CD4KO mice produced less IL10 than CD8KO mice. Furthermore, CD4KO mice had significantly reduced nevus numbers and size compared with wild-type and CD8KO mice. These results suggest that Tregs play a vital role in the incidence of nevi and their progression to melanoma.Prevention Relevance: There has been little progress in developing novel strategies for preventing premalignant dysplastic nevi from becoming melanomas. In this study in mice, regulatory-T cells enhanced progression of benign nevi to malignant melanomas; and by inhibiting their activity, melanomas could be retarded. The findings identify new possibilities for melanoma prevention in high risk individuals.

Eruptive Spitz nevus, a striking example of benign metastasis

Metastasis is generally considered a characteristic of malignant tumors. Herein, we describe a patient with more than one hundred discrete Spitz nevi scattered all over her skin. Molecular analysis from three of the lesions identified a ROS1 fusion oncogene with identical genomic breakpoints, indicating that the nevi arose from a single transformed melanocyte and then disseminated throughout the integument. The demonstration of widespread distribution of a benign tumor with limited proliferative capability indicates that metastatic dissemination is not contingent on full malignant transformation. Thus, eruptive Spitz nevus is a striking example of benign metastasis, demonstrating that metastasis can occur before malignant transformation.

Eruptive Melanocytic Nevi: A Review

Eruptive melanocytic nevi (EMN) is a phenomenon characterized by the sudden onset of nevi. Our objective was to compile all published reports of EMN to identify possible precipitating factors and to evaluate the clinical appearance and course. We conducted a systematic bibliographic search and selected 93 articles, representing 179 patients with EMN. The suspected causes were skin and other diseases (50%); immunosuppressive agents, chemotherapy or melanotan (41%); and miscellaneous, including idiopathic (9%). The clinical manifestations could largely be divided into two categories: EMN associated with skin diseases were frequently few in number (fewer than ten nevi), large, and localized to the site of previous skin disease, whereas those due to other causes presented most often with multiple small widespread nevi. In general, EMN seem to persist unchanged after their appearance, but development over several years or fading has also been reported. Overall, 16% of the cases had at least one histologically confirmed dysplastic nevus. Five cases of associated melanoma were reported. We conclude that the clinical appearance of EMN may differ according to the suggested triggering factor. Based on the clinical distinction, we propose a new subclassification of EMN: (1) widespread eruptive nevi (WEN), with numerous small nevi, triggered by, for example, drugs and internal diseases, and (2) Köbner-like eruptive nevi, often with big and few nevi, associated with skin diseases and most often localized at the site of previous skin disease/trauma. The nature of the data precluded assessment of risk of malignant transformation.

[Anti-TNF alpha-induced eruptive nevi: Three cases]

BACKGROUND

Eruptive melanocytic nevi (EMN) are a rare phenomenon characterized by simultaneous rapid onset of multiple nevi. The condition has been described in different contexts: immunosuppression, immunosuppressive drugs, targeted therapies, bullous diseases, and chemical melanocytic stimulation. We report 3 cases of EMN following anti-TNF alpha treatment.

PATIENTS AND METHODS

Case 1 - A 51-year-old female patient was receiving adalimumab for spondyloarthritis (the first treatment for this patient). A few months after the start of treatment, multiple nevi were noted on the 4 limbs, and in particular on the right palm. The patient confirmed the absence of these lesions before initiation of treatment. A diagnosis was made of adalimumab-induced EMN. Case 2 - A 49-year-old male patient was receiving etanercept for spondyloarthritis (the first biologic in this patient). Multiple small nevi developed on the trunk in the months after the start of treatment. The patient indicated that these lesions had appeared after the start of treatment. A diagnosis was made of etanercept-induced EMN. Case 3 - A 20-year-old woman with hidradenitis suppurativa was treated with infliximab. After 1.5 months, she reported the outbreak of various pigmented lesions 2-3mm in diameter on the trunk and one lesion on her right palm. The clinical diagnosis was EMN. After follow-up of 4 months to 5 years, no transformation to melanoma was noted in any of these 3 patients.

CONCLUSION

EMN remains a rare phenomenon in patients on anti-TNF alpha. These cases, associated with the description of a moderate increased risk of developing cutaneous carcinoma under anti-TNF alpha, underscore the need for dermatological follow-up and increased sun protection in patients receiving this treatment.

The High Multiplicity of Prenatal (Congenital Type) Nevi in Adolescents and Adults

In the absence of work on prenatal nevogenesis, it has long been necessary to define congenital melanocytic nevi by clinical detection on neonatal skin examination. They are seen in approximately 1% of newborns, with multiplicity in approximately 3% of cases. Melan-A staining of grossly normal fetal skin recently demonstrated fetal nevi, whose features validated certain traditional histologic criteria for "congenital type" nevi that may not have been detectable at birth. This suggested that many clinically acquired nevi actually formed in utero, like congenital nevi. Prenatal nevi has been suggested as a preferred synonym for "congenital type" nevi. Prenatal nevi were detected in 6 of 25 fetuses (24%), a strikingly higher incidence than congenital nevi in newborns. In this series of 354 patients with prenatal (congenital type) nevi encountered in routine practice at a community hospital, over 30% of both adolescents and adults had multiple prenatal nevi; a strikingly higher rate of multiplicity than congenital nevi in newborns. This high multiplicity may reflect origin beneath the epidermis, with many prenatal nevi working their way up to the surface of the skin decades after birth.

Melanocytic nevi and melanoma: unraveling a complex relationship

Approximately 33% of melanomas are derived directly from benign, melanocytic nevi. Despite this, the vast majority of melanocytic nevi, which typically form as a result of BRAF^V600E-activating mutations, will never progress to melanoma. Herein, we synthesize basic scientific insights and data from mouse models with common observations from clinical practice to comprehensively review melanocytic nevus biology. In particular, we focus on the mechanisms by which growth arrest is established after BRAF^V600E mutation. Means by which growth arrest can be overcome and how melanocytic nevi relate to melanoma are also considered. Finally, we present a new conceptual paradigm for understanding the growth arrest of melanocytic nevi in vivo termed stable clonal expansion. This review builds upon the canonical hypothesis of oncogene-induced senescence in growth arrest and tumor suppression in melanocytic nevi and melanoma.

Drug-induced eruptive melanocytic nevi

INTRODUCTION

The sudden eruption of melanocytic nevi has been associated with a number of conditions, such as bullous skin diseases, immunodeficiency and immunosuppression. The exact mechanisms leading to the development of eruptive melanocytic nevi are unknown. Areas covered: The aim of this article is to review the literature concerning eruptive melanocytic nevi following the administration of immunosuppressive drugs and other medications. Expert opinion: The literature regarding the development of eruptive nevi in association with pharmacological therapies includes a relatively low number of reports. Prevalence of this phenomenon is likely to be underestimated, thus reporting should be encouraged in order to better define the actual significance and related clinical implications. The development of multiple melanocytic nevi during immunosuppressive treatments highlights the importance of immune system integrity in the regulation of nevi growth. The observation of eruptive nevi as an unexpected effect of targeted therapies for specific types of cancer, including melanoma, provided intriguing hints to understand the mechanisms underlying this paradoxical event. The synergistic role of additional triggers in the occurrence of drug-induced eruptive nevi has not been explored and may be an interesting area of research.

Melan-A positive dermal cells in malignant melanoma in situ

The presence of Melan-A positive dermal cells in excisions for melanoma in situ represents a frequent conundrum for pathologists. These cells may represent superficially invasive melanoma, benign, incidental, dermal nevi or non-specific staining of dermal melanophages. Occasionally, rare, Melan-A positive dermal cells are present which do not clearly correspond to the above three categories. Our objective was to further characterize these Melan-A positive dermal cells. To do this, immunoperoxidase staining for Melan-A and SOX-10 was performed on 188-cutaneous excisions, including examples of melanoma in situ, atypical junctional melanocytic hyperplasia and non-melanocytic tumors. These were evaluated for the presence of Melan-A and SOX-10 positive dermal cells. Dermal cells, positive for both markers, were identified in 17% of the excisions. The cells were present in 10% of cases from the melanocytic group and 31% of the cases from the non-melanocytic group. These cells did not exhibit cytologic atypia and resembled neither the co-existing neoplasm nor melanophages. We conclude that positivity of these rare Melan-A positive cells for SOX-10 argues that they represent true melanocytes and not non-specific staining. The absence of cytologic atypia in these cells and their presence in excisions of non-melanocytic neoplasms argues that they are benign, reactive, dermal melanocytes.

[Childhood eruptive nevi: a case report]

"Eruptive nevi" is a phenomenon characterized by a rapid appearance of multiple melanocytic nevi. It is mainly developed in three groups of patients: those with systemic immunosuppression, bullous cutaneous disorders, and a melanocytic stimulation drug. We report on the case of an 11-year-old boy who was diagnosed with acute lymphoblastic leukemia. A few months after the beginning of the chemotherapy, he developed multiple pigmented lesions over the skin. Eruptive nevi syndrome has been described in the literature in 29 cases in the context of severe bullous disease and in immunosuppression. Nevi most often appear on the trunk and extremities, notably on the feet in the context of immunosuppression. They are localized in areas of bullous lesions in bullous diseases. Due to an increased melanocytic stimulation in eruptive nevi patients, long-term surveillance of individuals who have developed eruptive nevi is required, and increased sun prevention should be suggested.

Clinical and histologic findings in patients with uveal melanomas after taking tumor necrosis factor-α inhibitors

OBJECTIVE

To describe the progression of uveal melanocytic lesions to melanomas after initiation of tumor necrosis factor-α (TNF-α) inhibitors.

PATIENTS AND METHODS

We report 3 cases of uveal melanoma occurring after treatment with TNF-α inhibitors, 2 from Mayo Clinic and 1 from Yale University. The study took place from February 27, 2009, through July 15, 2013.

RESULTS

Two women and one man with inflammatory disease who received TNF-α inhibitors had subsequent development of uveal melanomas. The 2 women had inflammatory bowel disease and had been followed up for melanocytic tumors that grew markedly within 1 year after beginning treatment with TNF-α inhibitors to the point of requiring treatment. One had histologic confirmation of the melanoma. The male patient had rheumatoid arthritis that was being treated with TNF-α inhibitors. Serial ultrasonography was performed to monitor bilateral diffuse scleritis, and within 16 months of initiation of TNF-α inhibitor therapy, a choroidal mass was detected that continued to grow over the next 3 months. The patient elected to have enucleation, which revealed uveal melanoma and thinning of the sclera from the previous scleritis.

CONCLUSION

Our 3 cases of uveal melanocytic tumors occurring after the use of TNF-α inhibitors add to the growing literature suggesting a correlation between TNF-α inhibitors and the development of malignant neoplasms. Considering the association between cutaneous melanoma and TNF-α inhibitors, we recommend that patients have an eye examination before initiation of TNF-α inhibitors, and those with preexisting nevi should be followed up at regular intervals.

Eruptive Melanocytic Nevi Induced by Interferon for Nodal Metastatic Melanoma: Case Report and Review of the Literature

Background:

The rapid appearance of multiple new melanocytic nevi is known as eruptive nevi and has been well documented to occur with certain medications, in particular chemotherapeutic agents.

Methods:

We report a case of a woman with melanoma complicated by nodal metastasis who developed multiple melanocytic nevi while on high-dose interferon.

Results:

Serial photographs confirmed that the pigmented lesions were of new onset, whereas histology documented that the lesions were dysplastic nevi. A survey of the literature documented numerous causes of eruptive nevi, which we review. To date, interferon has not been linked to eruptive nevi.

Conclusions:

The phenomenon of eruptive nevi has been attributed to medications, bullous dermatoses, immunosuppression, and systemic conditions and is possibly a paraneoplastic disorder. Interferon appears to be another possible cause of this disorder.

[Eruptive melanocytic nevi during azathioprine therapy in myasthenia gravis]

While being treated with azathioprine and dexamethasone, a 21-year old man with myasthenia gravis suddenly developed rapidly progressing brown macules, predominantly on the trunk, palms and soles. We made a diagnosis of eruptive melanocytic nevi (EMN). This rare entity can appear after blistering skin diseases, in immunocompromised patients, and, in particular, during immunosuppressive therapy for autoimmune diseases. Since therapeutic regimens including azathioprine have been frequently reported in association with EMN, we recommended to our patient a treatment switch to mycophenolic acid to prevent the development of more nevi.

A case with postchemotherapy eruptive compound nevus

An 8-year-old male patient who had been diagnosed as acute lymphoblastic leukemia (ALL) 4 years ago and received 120 cures of chemotherapy presented at our clinic complaining of spots on his body 3 months after the end of chemotherapy. Anamnesis of the patient revealed that the lesions started 3 months after the last cure of chemotherapy on the abdomen and spread throughout the body. It was learnt that the number of spots increased very rapidly in a period of 2 months, and exceeded 100. A dermatological examination of the patient showed 142 hyperpigmented macules, the largest of which was 1 cm × 1 cm and the smallest was 0.2 cm × 0.2 cm in size, diffusely scattered to the skin and oral mucosa. When the biopsy material taken from the lesions was histopathologically examined, nest structures composed of nevus cells with oval nuclei and eosinophilic cytoplasm starting from the dermoepidermal junction and extending toward the lower epidermis were observed and found to be consistent with the compound nevus. We present this rare case who was diagnosed as “eruptive compound nevus” on the basis of clinical signs, ALL diagnosis, chemotherapy history and histopathologic evaluation.

[Eruptive naevi associated with octreotide treatment]

BACKGROUND

Octreotide is a synthetic octapeptide having properties related to those of natural somatostatin, a hypothalamic hormone. We report a case of eruptive naevus in patients treated with octreotide.

PATIENTS AND METHODS

A 52-year-old man consulted for multiple achromic naevi of recent onset. He was undergoing treatment with octreotide 30 mg per month for hepatic metastases in a setting of operated colonic carcinoid tumor. Since the start of this treatment, he had presented an efflorescence of diffuse naevus comprising over 200 lesions, certain of which were highly atypical. Annual follow-up was carried out. Ten years later, the patient was still alive and undergoing octreotide therapy at the same dose. The number of naevi had stabilized and there was no evidence of melanoma.

DISCUSSION

Eruptions of naevi are rare; they may occur at the sites of lesions in bullous diseases or during immunodepression (malignant or drug induced, HIV infection). There are questions concerning possible stimulation of naevus cells and the risk of onset of melanoma. Routine monitoring of pigmented lesions is thus necessary in patients treated with octreotide.

Identification of BRAF mutations in eruptive melanocytic nevi: new insights into melanomagenesis?

Eruptive melanocytic nevi (EMN) is an unusual phenomenon characterized by the abrupt, simultaneous appearance of hundreds of melanocytic nevi on previously uninvolved sun-exposed skin. The mechanisms underlying this phenomenon are not well understood, but have been associated with both systemic immunosuppression and bullous dermatoses. The paper under evaluation brings new insight into the molecular events underlying EMN development in a patient receiving 6-mercaptopurine immunosuppressive therapy for ulcerative colitis. Sequencing of DNA from 20 eruptive nevi revealed the presence of BRAF V600E mutations in 85% of the lesions tested. The role of mutated BRAF in the initiation and progression of melanoma in conjunction with the strong correlation between nevus number and melanoma risk suggests the need for photoprotection in patients receiving thiopurine therapy. The study under evaluation further points to the possible interaction between environmental mutagens and UV radiation in the acquisition of BRAF mutations that may in turn increase the risk of melanoma development.

Activating BRAF mutations in eruptive melanocytic naevi

BACKGROUND

Eruptive melanocytic naevi (EMN) are melanocytic proliferations developing rapidly on previously unaffected skin in association with various clinical scenarios, most commonly systemic immunosuppression. However, the exact mechanism leading to development of EMN is not understood. In particular, it is not known whether EMN harbour the BRAF mutations which occur frequently in melanoma and most common naevi.

OBJECTIVES

To evaluate whether activating BRAF mutations may play a role in genesis of EMN.

METHODS

Genomic DNA was isolated from 20 EMN from a patient treated with 6-mercaptopurine (6-MP). Primary BRAF genotyping was performed by allelespecific polymerase chain reaction, followed by validation using direct sequencing.

RESULTS

The BRAF V600E mutation was identified in 85% of EMN examined.

CONCLUSIONS

Our results implicate mutational activation of the BRAF–MAPK pathway as a factor in development of EMN in the setting of 6-MP treatment. The mechanism leading to development of EMN in this, and potentially other patients, may relate to synergistic mutagenic effects of thioguanines and ultraviolet (UV) A. Together with the documented importance of BRAF mutations in melanoma development and maintenance, these findings highlight the importance of UVA protection, especially in patients treated with thiopurines such as 6-MP.

Cyclin D1 and D3 expression in melanocytic skin lesions

Cyclins, cyclin-dependent kinases, as well as proteins cooperating with them are responsible for cell cycle regulation which is crucial for normal development, injury repair, and tumorigenesis. D-type cyclins regulate G1 cell cycle progression by enhancing the activities of cyclin-dependent kinases, and their expression is frequently altered in tumors. Disturbances in cyclin expression were also reported in melanocytic skin lesions. The objective of the study was to evaluate the expression of cyclins D1 and D3 in common, dysplastic, and malignant melanocytic skin lesions. Forty-eight melanocytic skin lesions including common nevi (10), dysplastic nevi (24), and melanomas (14) were diagnosed by dermoscopy and excised. Expression of cyclin D1 and D3 was detected by immunohistochemistry and quantified as percentage of immunostained cell nuclei in each sample. In normal skin, expression of cyclins D1 and D3 was not detected. The mean percentage of cyclin D1-positive nuclei was 7.75% for melanoma samples, 5% for dysplastic nevi samples, and 0.34% for common nevi samples. For cyclin D3, the respective values were 17.8, 6.4, and 1.8%. Statistically significant differences in cyclin D1 expression were observed between melanomas and common nevi as well as between dysplastic and common nevi (p = 0.0001), but not between melanomas and dysplastic nevi. Cyclin D3 expression revealed significant differences between all investigated lesion types (p = 0.0000). The mean cyclin D1 and D3 scores of melanomas with Breslow thickness <1 mm and >1 mm were not significantly different. G1/S abnormalities are crucial for the progression of malignant melanoma, and enhanced cyclin D1 and D3 expression leading to increased melanocyte proliferation is observed in both melanoma and dysplastic nevi. In histopathologically ambiguous cases, lower cyclin D3 expression in dysplastic nevi can be a diagnostic marker for that lesion type.

Cutaneous side effects of anti-tumor necrosis factor biologic therapy: a clinical review

BACKGROUND

Anti-tumor necrosis factor (anti-TNF) biologic agents have been associated with a number of adverse events.

OBJECTIVE

To review the cutaneous reactions that have been reported in patients receiving anti-TNF therapy.

METHODS

We performed a systematic MEDLINE search of relevant publications, including case reports and case series.

RESULTS

Reported cutaneous events included infusion and injection site reactions, psoriasiform eruptions, lupus-like disorders, vasculitis, granulomatous reactions, cutaneous infections, and cutaneous neoplasms. Infusion reactions and injection site reactions were definitely associated with anti-TNF administration, whereas all other events had a varying strength of association and severity, not necessarily requiring drug discontinuation.

LIMITATIONS

Most information was derived from spontaneous case reports, where ascertainment biases and frequency of reporting may impair detection methodology and causal relationships.

CONCLUSIONS

As anti-TNF biologic agents are progressively being used in clinical practice, cutaneous adverse events will be encountered more frequently. Until more data are accumulated with respect to their pathogenesis and potential association with anti-TNF therapy, dermatologists should become more familiar with the clinical presentation and management of such events.

Immunosuppression and melanocyte proliferation

Melanocytes are pigmented cells derived from the neural crest; their proliferation is restrained by immune system. The eruption of nevi after an immunosuppressive condition is a peculiar phenomenon indicating that the immune system may play a major role in limiting proliferation of melanocytes. In this review, we analyze the role of immunosuppressive regimens on melanocyte proliferation. In particular, we discuss the eruptive nevi phenomenon, which is determined by the inability of the immune system to inhibit melanocyte proliferation. These clinical observations indicate that the immune system has a pivotal role in restraining melanocyte proliferation. However, although the role of the immune system in the development of nonmelanoma skin cancer has been shown clearly in several studies involving organ transplant patients, the role of immunosuppression in melanoma genesis has not yet been established. Further investigations are required to establish the real immunogenicity of melanoma, particularly in the light of the dichotomy between the eruptive nevi phenomenon in immunosuppressed patients and the low incidence of melanoma in transplanted patients.

[Acral eruptive nevi after chemotherapy in children with acute lymphoblastic leukemia]

Eruptive melanocytic nevi have mainly been associated with blistering cutaneous diseases and with immunosuppression, particularly after renal allograft transplantation, hematological neoplasms, or HIV infection. Thus, immunosuppression has been suggested to increase the possibility of melanocyte proliferation. We report two cases of children with acute lymphoblastic leukemia who, after receiving chemotherapy, developed severe motor polyneuropathy, and sudden onset of multiple melanocytic nevi on the soles.

[Eruptive melanocytic nevi of the palms and soles in a patient with Crohn disease]

Eruptive melanocytic nevi of the palms and soles are a rare phenomenon which has been associated with a number of different diseases. A variety of pathogenetic mechanisms have been proposed. A 22-year-old woman with Crohn disease since 1998 presented with multiple eruptive melanocytic nevi of the palms and soles. She is the second case in the literature describing the association between Crohn disease and eruptive melanocytic nevi. In contrast to the first report by Belloni-Fortina et al., in our case the melanocytic nevi appeared only on the palms and soles.

Angiotropism in Epidermotropic Metastatic Melanoma

The diagnosis of epidermotropic metastatic malignant melanoma (EMMM) can be extremely challenging for both clinicians and pathologists. The diffculties include distinguishing metastatic lesions with an epidermal component from residual incompletely excised primary melanoma, and multiple primary melanomas. This has great prognostic significance as the current American Joint Committee on Cancer guidelines consider localized metastatic disease such as satellites and intransits in the nodal (N) category of N2C or stage IIIB disease. In this report, we present a case of EMMM with angiotropism. Additionally, we discuss in detail the differential diagnosis for recurrence of malignant melanoma with an epidermal component within the scar. Angiotropism may be seen in lesions of EMMM and the current literature suggests that angiotropism is highly suggestive of metastatic melanoma. The differential diagnosis of locally recurrent melanoma with an epidermal component can be extremely challenging and the presence of angiotropism may be a clue to the diagnosis of EMMM.

Clinical and dermatoscopic fading of post-transplant eruptive melanocytic nevi after suspension of immunosuppressive therapy

Excess melanocytic nevi have been reported in several groups of immunosuppressed patients, including organ transplant recipients. We report the case of a 16-year-old transplant recipient whose post-transplant melanocytic nevi decreased in size and color after graft rejection and interruption of immunosuppressive therapy. This case may represent a visual example of an effective immunosurveillance system against melanocytic nevi.

Induction of eruptive benign melanocytic naevi by immune suppressive agents, including biologicals

BACKGROUND

Eruptive naevi have been described to potentially arise in immune compromised patients.

OBJECTIVES

We describe three patients with eruptive benign melanocytic naevi during a phase of immunosuppressive therapy. METHODS/DIAGNOSIS: Two patients with Crohn disease were treated with either azathioprine monotherapy or a combination of azathioprine and infliximab, when eruptive naevi arose particularly at the palms and soles. Our third patient with plaque psoriasis developed eruptive naevi during two episodes of treatment: during a course with the biological agent alefacept and during etanercept therapy.

CONCLUSIONS

We conclude that treatment with the recently available biological agents might be associated with the formation of eruptive naevi. Although positive evidence for the occurrence of malignant pigmented lesions is lacking, alertness to the development of eruptive melanocytic naevi during treatment with biological agents is indicated.

Nevogenesis-New Thoughts Regarding a Classical Problem

The development of melanocytic nevi is a multifactorial and heterogeneous biologic process that involves prenatal and postnatal steps. As a consequence, there are two main perspectives to nevi: that of a hamartoma and that of a benign tumor. In this review, dermatopathological studies on congenital and acquired nevi, including studies on age-related and location-dependent changes, are analyzed. These studies have lead to different hypothetical concepts on the evolution of individual lesions. In the light of findings from experimental embryology and stem cell biology, we discuss the histogenesis of nevi with special reference to the temporospatial sequence of melanocyte-basement membrane interactions and hair follicle genesis. Regarding the mechanisms of postnatal nevus development, epidemiological studies demonstrate the importance of constitutional and environmental influences, especially ultraviolet light. Possible molecular pathways of solar nevogenesis involve ultraviolet-induced alterations of the cellular microenvironment (eg, changes in the expression of cytokines and melanocyte adhesion molecules). Recent results and future directions of clinical and experimental research are presented.