Epidermoid cysts in kidney transplant patients receiving tacrolimus.

We present a series of three kidney transplant patients developing epidermoid cysts after receiving oral tacrolimus for long-term prevention of rejection of the allograft. Cyclosporin A has been known to show this cutaneous adverse drug reaction, but this is the first series of patients with epidermoid cysts following tacrolimus to the best of our knowledge.

[Eruptive epidermoid cysts after imiquimod treatment of recurrent basal cell carcinoma : A case report]. / Eruptive Epidermoidzysten nach Imiquimod-Therapie eines rezidivierenden Basalzellkarzinoms : Ein Fallbericht.

Eruptive epidermoid cysts are a rare adverse event of imiquimod treatment for basal cell carcinoma. Up to date, 8 cases have been described in the literature. We present the case of a 75-year-old Caucasian woman with recurrent basal cell carcinoma on the nose. After multiple excisions and treatment with vismodegib, imiquimod 5% cream was administered 5 times per week over 6 weeks. Two months after the end of treatment, the patient presented with eruptive epidermoid cysts.

RASopathic comedone-like or cystic lesions induced by vemurafenib: a model of skin lesions similar but not identical to those induced by dioxins MADISH.

BACKGROUND: Patients treated with vemurafenib for metastatic melanoma often develop skin lesions similar to those observed after exposure to dioxin-like compounds. We previously called these lesions MADISH (metabolizing acquired dioxin-induced skin hamartoma) when analysing a case of acute dioxin poisoning. OBJECTIVE: We performed a clinical trial aimed at comparing the skin lesions observed under vemurafenib treatment with MADISH in order to bring to light a possible crosstalk between vemurafenib and dioxin pathways. METHODS: In this case series study, we explored the histological aspect of skin lesions in 10 cases treated with vemurafenib for malignant melanoma. We also analysed the ability of vemurafenib and tyrosine kinase inhibitors to induce dioxin-AhR pathway. RESULTS: All patients had skin lesions diagnosed as 'non-inflammatory acneiform eruption' by dermatologists. These were predominantly facial with notable retroauricular involvement and clinically compatible with chloracne/MADISH when assessed by dioxin expert. Histological analysis showed mostly comedone-like lesions and dermal cysts containing epithelial wall with basal or lateral epithelial projections and lamellar keratinization and alterations of remaining sebaceous glands. The expression of CYP1A1, a gene highly induced following dioxin exposure, was not observed in these lesions. Vemurafenib and the tyrosine kinase inhibitors erlotinib and gefitinib did not induce CYP1A1 activity. DISCUSSION: Although the skin lesions under vemurafenib treatment were morphologically similar to MADISH, the absence of CYP1A1 expression in dermal cysts of patients and the absence of CYP1A1 activation by vemurafenib led us consider that these skin lesions were different from true MADISH and not mediated by a crosstalk of AhR signalling, but rather to a hyperactivation of PI3K-Akt pathway as a consequence of vemurafenib treatment. A strong expression of CYP1A1 in the epithelial wall of dermal cysts must be required, parallel to the morphology of the lesions, to make the diagnosis of MADISH, the hallmark of an exposure to dioxin-like/chloracnegen compounds.

Cutaneous Epithelial Lesions Induced by N-Methyl-N-nitrosourea in Male Sprague-Dawley Rats: A Possible Animal Model for Human Keratoacanthoma.

A single intraperitoneal injection of 50 or 75 mg/kg N-methyl-N-nitrosourea in male Sprague-Dawley rats at 4 weeks of age, dose-dependently resulted in cutaneous epithelial cysts and tumors of pilosebaceous origin. Cysts were composed of epidermal cysts or mixed epidermal and inner root sheath hybrid cysts. The majority of induced tumors were keratoacanthomas. A few tumors were trichofolliculomas, trichoblastomas, pilomatricomas, or sebaceous adenomas. All tumors were benign pilosebaceous tumors. Keratoacanthomas were crater-shaped tumors with thick infoldings of epithelium containing keratohyalin granules (epidermal lip) that abruptly changed to epithelium containing trichohyalin granules. The morphological similarity and resemblance of keratin 1, 10, and 14 profiles, and p63 and ß-catenin expression between mixed epidermal and inner root sheath hybrid cysts and keratoacanthomas suggests that hybrid cysts progressed to keratoacanthomas, and the cells from infundibular cells to inner root sheath cells of the pilar segment seem to be the origin of rat keratoacanthomas. Immunohistochemical localization of keratins 1, 10 and 14, p63, and ß-catenin in trichofolliculoma, trichoblastoma, and pilomatricoma, as well as keratoacanthoma, may indicate tumor histogenesis.

Enfuvirtide and cutaneous injection-site reactions.

Enfuvirtide belongs to a newer class of antiretroviral (ARV) agents called fusion inhibitors for the treatment of human immunodeficiency virus type 1 (HIV-1) infection. Enfuvirtide blocks attachment, binding, and entry of the viral capsid into the host CD4+ cell. Administration is only available subcutaneously in a twice-daily regimen particularly for those patients who have previously failed more than one ARV regimen. Common side effects of enfuvirtide administration include fatigue, insomnia, nausea, and diarrhea; however, injection-site reactions are the most common side effect and present in nearly all individuals undergoing treatment. The spectrum of cutaneous manifestations ranges from little to no reaction to cysts, nodules, induration, or sclerodermalike lesions. These reactions are mostly variants of iatrogenically induced hypersensitivity and are self-limited.

Multiple and clustered eruptive epidermoid cysts following treatment with topical imiquimod.

A 61-year-old woman developed multiple and clustered eruptive epidermoid cysts at the site of treatment of a basal cell carcinoma located on her nose with imiquimod 5% cream (5 times/week for 6 weeks). Clearing was achieved after topical treatment with tretinoin 0.025% cream (1 application/day for 1 month).

Classification of cystic keratinizing squamous lesions of the rat lung: report of a workshop.

An international workshop of toxicologic pathologists reviewed cystic keratinizing squamous lesions of the rat lung. These lesions develop in response to the chronic inhalation of diverse particulate materials. Controversy exists over the biological significance of these changes and their relevance to humans. For the first time, in one place, a group of pathologists analyzed slides from all available studies. The workshop reached a consensus as to classification of these unique pulmonary tissue responses and offers diagnostic criteria for application. Although additional research is needed, this working classification scheme should serve as a practical interim approach for pathologists and regulatory agencies.

N-ethyl-N-nitrosourea treatment of multiple intestinal neoplasia (Min) mice: age-related effects on the formation of intestinal adenomas, cystic crypts, and epidermoid cysts.

The timing of intestinal tumor initiation in B6-Min/+ mice has been examined by treating mice at 5-35 days of age with a single i.p. injection of the direct-acting alkylating agent N-ethyl-N-nitrosourea (ENU). Treatment of Min/+ mice at 5-14 days of age resulted in a 3.8-fold increase in intestinal tumor multiplicity over untreated mice. Mice treated at 20-35 days of age showed only a 1.6-fold increase in tumor number. These results, in conjunction with examination of tumor multiplicities of untreated Min/+ mice as a function of age, suggest that the majority of intestinal tumors in Min/+ mice are initiated relatively early in life. Min/+ mice treated with ENU also showed an increase in the number of cystic intestinal crypts. However, the relationship between age at ENU treatment and cystic crypt multiplicity was distinct from that seen for intestinal adenomas. Mice treated at 5-9 days of age showed only a 1.9-fold increase in cystic crypts over untreated animals. By contrast, the increase in average cystic crypt multiplicity for mice treated at 10-35 days of age was 4.5-fold. In addition, 60% of Min/+ mice treated with ENU before 25 days of age developed epidermoid cysts, an extracolonic manifestation commonly associated with familial adenomatous polyposis in humans.

Immunohistochemical localization of estrogen receptors in the submandibular gland tumors of female rats.

The localization of estrogen receptors (EsR) in the tumor tissues of submandibular glands was examined in female rats, using the indirect immunoperoxidase method in combination with the in situ hybridization technique. Tumors were experimentally produced by 9,10-dimethyl-1,2-benzanthracene (DMBA), and the tumor tissues were fixed with formalin or paraformaldehyde and then embedded in paraffin. In the DMBA-induced submandibular gland tumors, immunoreactivity to EsR-peroxidase conjugate was found in nuclei of the tumor cells which occupied the peripheral rim of the tumor cell nests. In contrast, the reactivity in the normal submandibular glands without tumor was mostly confined to nuclei of the duct cells. When EsR mRNA expression was analyzed in the tumor tissue by in situ hybridization with a cDNA probe, its distribution was identical with that of immunoreactivity to EsR. These data suggest that the ductal cells of the submandibular gland are responsive to ovarial steroids, and that estrogens may play an important role in the maintenance of growth of the submandibular gland tumors.

[Epidermal cysts and folliculitis caused by cyclosporin A]. / Epidermalzysten und Follikulitiden durch Cyclosporin A.

A 66-year-old man was treated with cyclosporin A (Sandimmun) after a kidney transplant and developed numerous epidermal cysts, comedones and folliculitis in the 2nd year of the immunosuppressive therapy. The eruptions were more marked on the back and in the temporal and retroauricular regions of the face. Histological examination of a cystic tumour revealed a follicular cyst of the acro-infundibular type. While hypertrichosis and gingival hyperplasia are now well known as side effects of cyclosporin A, cystic and acneiform skin lesions must also be attributed to this drug.

Multiple epidermoid cysts in a renal transplant recipient taking cyclosporine A.

A forty-two-year-old male recipient of a cadaver renal transplant showed multiple nodulocystic lesions on his back and lateral aspects of his neck four months after beginning immunosuppressive therapy with cyclosporine A and prednisone. Results of histopathologic studies revealed that they were epidermoid infundibular cysts. We note the relationship between this clinical appearance and cyclosporine A, as well as this agent's cutaneous side effects.

Eruptive epidermal cysts and multiple squamous cell carcinomas after therapy for cutaneous T-cell lymphoma.

Both topical nitrogen mustard and psoralen photochemotherapy may induce benign and malignant alterations in the skin. We describe the explosive appearance of multiple epidermal cysts and squamous cell carcinomas in a patient whose cutaneous T-cell lymphoma was treated sequentially with these two types of therapy. This is the first report of both processes in the same patient with cutaneous T-cell lymphoma. It strongly supports the concept of lesion induction, while raising the question of an additive or even synergistic effect of these types of therapy.

Clobetasol-induced milia.

Milia developed in two patients with different chronic dermatoses after 2 weeks of treatment with clobetasol propionate ointment. Routine histologic and immunohistochemical analysis showed the cysts to be of eccrine gland origin.

Epithelial cutaneous lesions induced in Dunkin-Hartley albino guinea-pigs by means of 7,12-dimethyl-benzanthracene.

We carried out a clinicopathological study of epithelial cutaneous lesions induced in Dunkin-Hartley albino guinea-pigs by means of the topical application of 7,12-dimethyl-benzanracene. By the end of the study we had observed 4451 lesions. Most frequently observed were epithelial hyperplasia and dysplasia (2544 lesions). Neoplasias consisted of 244 carcinomas in situ, and 88 squamous carcinomas. Basal-cell epitheliomas were few. Epidermal cysts were a frequent finding.

Otologic manifestations of the hydantoin syndrome.

The temporal bones of a newborn infant with hydantoin syndrome showed multiple middle ear and inner ear anomalies. There was a constellation of bony and membranous defects involving the oval and round windows, cochlear ducts, cochlear aqueducts, endolymphatic ducts and sacs, and vestibular labyrinths. To the authors' knowledge, supernumerary vestibular sensory epithelial structures and an inner ear epidermoid cyst have not been previously reported. Wide communications between the subarachnoid space and inner ear were of surgical relevance.