Panniculitis with vasculitis.

Panniculitides encompass a great number of different entities; however, once a vasculitis has been detected histopathologically within the subcutaneous tissue, the differential diagnosis is mainly restricted to polyarteritis (panarteritis) nodosa (PAN), nodular vasculitis (NV), and Bazin's erythema induratum (EI). Patients with PAN may have the disease confined to the skin, but must be followed over a long period because many of them develop late systemic disease. The NV/EI group represents by far the most common type of lobular panniculitis with vasculitis; we prefer keeping the distinction between the two entities by underlining the equation NV positive tuberculin skin test = EI. Other lobular panniculitides with vasculitis are exceedingly rare and set in a systemic background which can be infectious (lepromatous leprosy panniculitides) or autoimmune/dysreactive (neutrophilic lobular panniculitis in rheumatoid arthritis, lobular panniculitis in inflammatory bowel disease).

p53 mutations and chromosome instability in basal cell carcinomas developed at an early or late age.

Tumor DNA from 45 primary basal cell carcinoma (BCC) biopsies was screened for p53 gene mutations, chromosome 9 allele loss, and microsatellite instability. p53 mutation frequency increased significantly as a function of the age at BCC onset ranging from 6% (1/16) in early BCC (before age 40 years) to 35% (10/29) in late BCC. All p53 mutations found implicated sunlight as the mutagen. Chromosome 9 instability (allele loss or microsatellite instability) was detected at high frequency (38%) independently of age at tumor onset. Allelic loss was confined to chromosome 9q, whereas microsatellite instability was observed prevalently on chromosome 9p often in association with a replication error (RER+) phenotype. Most of our late BCC patients reported occupational sun exposure, while early BCC patients recalled childhood (0-20 years) recreational sun exposure. These data suggest that chronic exposure to sunlight is responsible for accumulation of p53 mutations and thus for late BCC appearance, whereas acute UV exposure in childhood and adolescence leads to early skin cancer development in genetically susceptible individuals via a p53-independent pathway.

Melanocytic nevi of palms and soles: a histological study according to the plane of section.

Melanocytic nevi of palms and soles (MNPS) cause diagnostic problems to dermatopathologists because they share histologic features with malignant melanoma (MM). Early MNPS frequently display a striate appearance, suggesting that, in this subset of nevi, both melanocytes and melanin might have a particular distribution in relation to dermatoglyphics. To verify this hypothesis, we undertook a histological study on 78 junctional MNPS sampled along a plane either perpendicular or parallel to dermatoglyphics. Histologic examination revealed symmetry in 56% of the lesions, circumscription in 60%, intraepidermal scatter of melanocytes in 79%, and melanin columns in 61%. Interestingly, comparison between histologic features of nevi sampled perpendicularly and those of nevi cut parallely to dematoglyphics showed that features of benignity, namely symmetry, circumscription and melanin columns, were significantly more frequent in lesions dissected along a perpendicular plane. Moreover, in 70% of perpendicular samples, intraepidermal scatter of melanocytes and melanin columns were strictly concentrated in furrows. Therefore, to avoid diagnostic pitfalls in the differentiation between junctional MNPS and MM, we strongly suggest to dissect MNPS along a plane perpendicular to skin markings. We hypothesize that mechanical stress can be responsible for concentration of intraepidermal scatter of melanocytes and melanin columns in skin furrows.

Primary cutaneous marginal zone B-cell lymphoma: a recently described entity of low-grade malignant cutaneous B-cell lymphoma.

Recently a new classification of primary cutaneous B-cell lymphomas (PCBCLs) has been proposed by the European Organization for Research and Treatment of Cancer (EORTC)--Cutaneous Lymphoma Project Group. The marginal zone B-cell lymphomas (MZLs) were not included as a distinct entity because of insufficient experience and controversial opinions. We have studied 32 patients (M:F ratio 1.5:1; age range 25-93 years; mean age 49.6 years; median age 50 years) to determine the diagnostic criteria of primary cutaneous MZL and the relationship with other low-grade malignant PCBCLs. For comparison, three patients with immunocytoma were included in the study. Clinically, patients presented with solitary or clustered reddish or red-brown papules, nodules, and plaques, sometimes surrounded by an erythematous halo. Histopathologic sections showed nodular or diffuse infiltrates involving the dermis and subcutaneous fat. Cytomorphologically small to medium-sized cells with indented nuclei and abundant pale cytoplasm (marginal zone cells, centrocyte-like cells) predominated. In addition, scattered blasts, lymphoplasmacytoid cells, and plasma cells were observed below the epidermis and at the periphery of the infiltrates. Reactive germinal centers were present in 75% of the cases. The three cases of immunocytoma showed a more monomorphous pattern with predominance of lymphoplasmacytoid cells. The marginal zone cells showed a CD20+, CD79a+, CD5- and Bcl-2+ immunophenotype. They expressed immunoglobulin G in the majority of the cases. Staining with the monocytoid B cell-related antibody KiM1p gave positive results in all specimens with a typical intracytoplasmic granular pattern. A monoclonal distribution of immunoglobulin light chains was observed in marginal zone cells in 75% of the cases. Germinal centers, when present, were either polyclonal or negative for both kappa and lambda light chains. Monoclonal rearrangement of the JH gene was detected via polymerase chain reaction (PCR) in 18 of 26 investigated specimens. Analysis in 12 patients of the bcl-2/immunoglobulin heavy chain gene rearrangement using PCR yielded negative results. Lesions were treated by surgical excision followed in some patients by local radiotherapy. Systemic antibiotic therapy was administered to three patients, with good response in two. The prognosis is excellent. After a mean follow-up of 47.9 months (range 6-252; median 24) all patients are alive without signs of systemic lymphoma. Primary cutaneous MZL represents a distinct clinicopathologic subtype of low-grade malignant PCBCL.

Infantile acute hemorrhagic edema of the skin.

Infantile acute hemorrhagic edema (AHE) of the skin is an uncommon form of cutaneous leukocytoclastic vasculitis that occurs in children younger than 3 years. We describe a 10-month-old boy with AHE, in whom the disease appeared after antibiotic treatment for an acute respiratory illness. AHE presented with fever, acral edema, and rosette-shaped purpuric plaques on the face and limbs. The causes of AHE are unclear, as is its nosologic position. Some authors consider the disease as a purely cutaneous form of Henoch-Schönlein purpura, and others believe that AHE should be regarded as a distinct clinicobiologic entity within the spectrum of leukocytoclastic vasculitis.

Basal cell and squamous cell carcinomas. Clinico-histological features.

Basal cell and squamous cell carcinomas are the most common skin cancers, occurring mainly on sun-damaged skin of old persons. Basal cell carcinoma is a neoplasm of follicular germinative cells which may infiltrate and destroy adjacent tissues, but rarely metastasizes. Five clinico-pathologic types of basal cell carcinomas can be recognized, namely, nodulo-ulcerative, superficial, morpheiform, fibroepithelial, and infundibulo-cystic. Actinic keratosis and Bowen's disease are intrepidermal proliferation of atypical keratinocytes that eventually may progress to become over squamous cell carcinoma. Lesions arising in sites of chronic injury or scarring bear an higher risk of metastases. Keratoacanthoma is a rapidly evolving tumor of keratinocytes that resolves spontaneously. Keratoacanthoma might represent a self-healing type of squamous cell carcinoma.

[Tricholemmal hamartoma]. / Amartoma tricolemmale.

A 23-year-old man with a keratotic-nodular lesion localized on the neck since infancy is reported. Histologically, there was a funnel-shaped follicle with central horny material and multiple digitations of the follicular sheath epithelium with some features resembling dilated pore of Winer. In addition, there were pale dyskeratotic epithelial cells in the infundibular portion of the tumor and in the surrounding epidermis. For this unusual tumor the term of tricholemmal hamartoma is proposed.

Granulocyte/macrophage colony-stimulating factor treatment of human chronic ulcers promotes angiogenesis associated with de novo vascular endothelial growth factor transcription in the ulcer bed.

Summary Background Granulocyte/macrophage colony-stimulating factor (GM-CSF), a cytokine with pleiotropic functions, has been successfully employed in the treatment of chronic skin ulcers. The biological effects underlying GM-CSF action in impaired wound healing have been only partly clarified. Objectives To investigate the effects of GM-CSF treatment of chronic venous ulcers on lesion vascularization and on the local synthesis of the angiogenic factors vascular endothelial growth factor (VEGF) and placenta growth factor (PlGF). Methods Patients with nonhealing venous leg ulcers were treated with intradermal injection of recombinant human GM-CSF, and biopsies were taken at the ulcer margin before and 5 days after administration. Wound vascularization was analysed by immunohistochemistry using antiplatelet endothelial cell adhesion molecule-1/CD31 and anti-alpha-smooth muscle actin antibodies. VEGF and PlGF transcription was assessed by in situ hybridization. To identify the cell populations transcribing VEGF within the ulcer bed, the VEGF hybridization signal was correlated with the immunostaining for different cell type markers on serial sections. Direct induction of VEGF transcription by GM-CSF was investigated in GM-CSF-treated cultured macrophages and keratinocytes. Results Blood vessel density was significantly increased in the ulcer bed following GM-CSF treatment. VEGF transcripts were localized in keratinocytes at the ulcer margin both before and after GM-CSF treatment, whereas a VEGF hybridization signal was evident within the ulcer bed only following administration. PlGF mRNA was barely detectable in keratinocytes at the ulcer margin and was not visibly increased after treatment. Unlike VEGF, a specific PlGF hybridization signal could not be detected in cells within the ulcer following GM-CSF administration. Monocytes/macrophages were the main cell population transcribing VEGF after GM-CSF treatment. In vitro analysis demonstrated that VEGF transcription can be directly stimulated by GM-CSF in a differentiated monocytic cell line, but not in keratinocytes. Conclusions Our data show that increased vascularization is associated with GM-CSF treatment of chronic venous ulcers and indicate that inflammatory cell-derived VEGF may act as an angiogenic mediator of the healing effect of GM-CSF in chronic ulcers.

Persistent unilateral orbital and eyelid oedema as a manifestation of Melkersson-Rosenthal syndrome.

Melkersson-Rosenthal syndrome (MRS) is a complex neuromucocutaneous disorder characterized by localized orofacial oedema and cranial nerve dysfunction, frequently associated with minor signs, including furrowed tongue. Complete forms are rare whereas mono- and oligosymptomatic variants are more common. A 71-year-old man presented with a 2-year history of relapsing and progressively persistent oedema of the right eyelids and periorbital region. A fissured tongue and telangiectatic rosacea had been present since the age of 50 and 60 years, respectively. The patient was also affected by essential hypertension and diabetes mellitus. A skin biopsy showed a marked upper dermal oedema, and small epithelioid cell granulomas arranged in perivascular and perilymphatic location. Collections of small epithelioid cells were occasionally observed within lymphatic spaces. No acid-fast bacteria, fungi or foreign bodies were detected. Intralesional corticosteroids induced transient improvement, whereas minocycline, clofazimine and dapsone have been ineffective. MRS may present with unilateral eyelid and periorbital swelling. Differential diagnoses of such cases may include a variety of cutaneous, ophthalmic and systemic diseases.

Tufted folliculitis of the scalp: a distinctive clinicohistological variant of folliculitis decalvans.

Tufted folliculitis is an uncommon folliculitis of the scalp that resolves with patches of scarring alopecia within which multiple hair tufts emerge from dilated follicular orifices. The clinicohistological data from a group of 15 patients with tufted folliculitis were reviewed and compared with those of seven patients with folliculitis decalvans, five with acne keloidalis nuchae, four with dissecting cellulitis of the scalp, three with kerion celsi and 20 with follicular lichen planus. It was found that tufted folliculitis could be differentiated from folliculitis decalvans only by finding several hair tufts scattered within patches of scarring alopecia. Histologically, a single tuft consisted of peculiar clustering of adjacent follicular units opening at the bottom of an epidermal depression. Conversely, the presence of keloidal plaques in acne keloidalis nuchae, coalescing nodules discharging purulent material in dissecting cellulitis of the scalp, erythematous plaques covered by pustules replete with fungal elements in kerion celsi, and the absence of follicular pustules in follicular lichen planus distinguished these diseases from tufted folliculitis. On the basis of these findings, it is suggested that tufted folliculitis should be considered as a distinctive clinicohistological variant of folliculitis decalvans. Tufting of hair is caused by clustering of adjacent follicular units due to a fibrosing process and to retention of telogen hairs within the involved follicular units.

Purely cutaneous Rosai--Dorfman disease.

Cutaneous lesions of Rosai-Dorfman disease (RDD) are usually associated with nodal or other extranodal localization. We describe a female patient with RDD clinically limited to the skin. The patient presented with asymptomatic red-brown papules and nodules on the legs, arms, back, and nose. Histologically, the lesions consisted of a proliferation of large histiocytes occasionally showing emperipolesis. Histiocytes were also observed within dilated lymphatic vessels. Immunohistochemical study showed that histiocytes expressed S-100 protein and both macrophage and monocyte markers. All lesions resolved completely with Roentgen therapy. No recurrence has been observed over a 3-year follow-up period.

Multinucleate cell angiohistiocytoma.

We report a case of multinucleate cell angiohistiocytoma occurring in a 50-year-old woman and presenting with a 4-year history of asymptomatic red papules on the face. Histologically, there was a dermal vascular proliferation associated with numerous multinucleate cells. Immunohistochemical studies showed vascular spaces surrounded with mature vascular endothelial cells, and the presence of numerous interstitial factor XIIIa+ cells. Multinucleate cells exhibited intermediate filaments of the vimentin type, but were not stained by endothelial cell or macrophage markers, and were factor XIIIa-. This condition must be addressed in the differential diagnosis of other skin vascular proliferations, such as Kaposi's sarcoma and angiofibromas.

Cutaneous phaeohyphomycosis due to Cladosporium cladosporioides.

A 54-year-old man, affected by pemphigus vulgaris and severe steroid-induced diabetes, developed seven red-brown, firm, slightly raised 0.1-1 cm papular lesions on the anterior aspect of both knees and thighs. A cutaneous biopsy showed a granulomatous infiltrate with numerous fungal elements scattered in the dermis and also within giant cells. Cultures of cutaneous biopsy fragments on Sabouraud glucose agar in presence of chloramphenicol resulted in the growth of dark-green colonies at 25 degrees C. They were identified as typical Cladosporium cladosporioides. As far as we know, this species was previously isolated only in an HIV-seropositive patient as opportunistic pathogen in the site of skin testing.

Nucleolar organizer regions in malignant melanoma and melanocytic nevi. Comparison of two counting methods.

Using a silver staining technique, we studied nucleolar organizer regions (AgNOR) in paraffin sections of junctional nevi, compound nevi, intradermal nevi, blue nevi, dysplastic nevi, Spitz nevi, lentigo maligna, malignant melanomas in nevus, superficial spreading melanomas, and nodular melanomas. Two methods of counting black dots within nuclei were employed. One method was to count the discrete black dots within the nuclei, including the tiny black dots seen within the nucleolus; the second method did not take into account the subsidiary cluster of tiny black dots seen within the nucleolus, instead treating these dots as a single structure. Whichever method we used, a significant difference was found between the pooled mean AgNOR numbers for benign and malignant lesions. We found an overlap, however, between benign, in particular Spitz and dysplastic nevi, and malignant lesions when considering individual counts of AgNOR using both methods. We conclude that studying AgNOR does not seem to be a useful technique to differentiate Spitz and dysplastic nevi from malignant melanomas.

Cutaneous metastasis of chordoma.

A chordoma metastatic to the skin of the nose is reported. The patient (a 40-year-old man) had undergone excision of a sacral chordoma 16 months previously. In patients whose clinical histories are unknown, cutaneous metastases of chordoma can be confused with mixed tumors of sweat glands. Cytological features, including the presence of physaliphorous cells, and immunohistochemical coexpression of low molecular weight keratins and S-100 protein are helpful features that lead to a correct diagnosis.

Minimally differentiated acute myeloid leukaemia revealed by specific cutaneous lesions.

Minimally differentiated acute myeloid leukaemia (AML-MO) is a poorly differentiated type of acute myeloid leukaemia. Its myeloid differentiation can only be demonstrated by the immunohistochemical or ultrastructural finding of cytoplasmic myeloperoxidase in bone marrow blasts and/or by the immunohistochemical expression of at least one lineage-specific myeloid antigen, with no reactivity for lymphoid antigens. We describe a man with a cutaneous nodular eruption that represented the first clinical manifestation of AML-MO. Histological examination showed extensive proliferation of blasts with scant basophilic cytoplasm. Immunohistochemically, these expressed neither myeloid nor lymphoid-specific antigens, whereas they were focally positive for CD45. The diagnosis of AML-MO was confirmed by immunophenotypic analysis of a bone marrow smear. A complete remission was achieved following parenteral steroid therapy. The disease relapsed some months later, and the patient died within a few weeks.

Congenital dermatofibrosarcoma protuberans.

Congenital dermatofibrosarcoma protuberans occurred in a 16-year-old girl. The lesion was a hard cutaneous plaque on the abdomen. It was present at birth and slowly enlarged during the patient's lifetime. Histologic examination was essential to establish the diagnosis and to differentiate it from other congenital fibrohistiocytic proliferations.