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Background: Clinical information on histologic referral sheets is usually very limited, and particularly for inflammatory skin disorders, dermatopathologists often ask referring physicians for clinical correlation., Objective: In this study we tested the value of clinicopathologic correlation in the histopathologic diagnosis of inflammatory skin disorders., Methods: One-hundred biopsy specimens were digitalized and stored on 3 DVDs along with the clinical images. All cases were evaluated by 9 independent full-time dermatopathologists, initially without looking at the clinical pictures and subsequently after checking them. All diagnoses were finally compared with the "reference" diagnosis established in Graz, Austria, and the results were statistically analyzed., Results: After evaluation of the clinical images, the number of dermatopathologists making a correct diagnosis was increased in 70 cases, unchanged in 25 cases, and decreased in 5 cases. The total number of correct diagnoses increased from 332 (diagnoses before evaluation of clinical pictures) to 481 (diagnoses after evaluation of clinical pictures), with a 16.6% increase in the total., Limitations: The computerized setting is different from real-life dermatopathology and physical examination of patients., Conclusion: Our study clearly shows that clinical pictures should be added to biopsy request slips of inflammatory skin disorders whenever possible, as they allow a better interpretation of histopathologic findings., (Copyright © 2009 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.)

Galli-Galli disease (GGD), a rare genodermatosis in the spectrum of reticulate hyperpigmentation, is regarded as an acantholytic variant of Dowling-Degos disease. We herein report two patients with GGD exhibiting erythematous scaly plaques and lentigo-like macules on the trunk and lower extremities, rather than the characteristic reticulate hyperpigmented macules of large body folds. Digitate elongations of rete ridges coupled with foci of acantholysis were the clues to the diagnosis. A high index of suspicion is needed to diagnose GGD that lacks the characteristic reticulate hyperpigmentation of large body folds.

Objectives: We sought to evaluate the frequency and clinical characteristics of pruritic dermatoses in pregnancy and to assess a rationalized classification., Methods: Data of 505 pregnant patients seen at two university-based dermatologic hospitals (1994-2004) were retrospectively studied., Results: Diagnoses included eczema in pregnancy (49.7%), polymorphic eruption of pregnancy (PEP) (21.6%), pemphigoid gestationis (PG) (4.2%), intrahepatic cholestasis of pregnancy (ICP) (3%), prurigo of pregnancy (0.8%), pruritic folliculitis of pregnancy (0.2%), and miscellaneous dermatoses (20.6%). Eczema in pregnancy, prurigo of pregnancy, and pruritic folliculitis of pregnancy showed considerable overlap and were summarized as atopic eruption of pregnancy (AEP). While PEP, PG, and ICP presented in late pregnancy, AEP started significantly earlier. Primigravidae and multiple gestations were characteristic for PEP, abdominal involvement for PEP and PG, and a history of affected pregnancies for ICP., Limitations: This was a retrospective study., Conclusion: We propose classifying the dermatoses of pregnancy as PG, PEP, AEP, and ICP. Stereotypic immunofluorescence and laboratory findings are diagnostic of PG and ICP, whereas distinct clinical characteristics facilitate discrimination between PEP and AEP.

Acrodermatitis chronica atrophicans, the characteristic cutaneous manifestation of late Lyme borreliosis, typically occurs in elderly women. To our knowledge, only 4 cases of acrodermatitis chronica atrophicans in children have been described. Prompt diagnosis and treatment are important to prevent progression of disease and extracutaneous complications. We describe a 15-year-old girl with acrodermatitis chronica atrophicans of the left leg that had been misdiagnosed as chronic venous insufficiency for 6 years. Because of the long-standing disease course, skin changes expanded and progressed to marked atrophy. The correct diagnosis was finally based on clinical, histopathologic, and serologic findings. The girl was treated with oral doxycycline for 6 weeks, but her skin changes did not fully normalize. This case illustrates the possibility of acrodermatitis chronica atrophicans appearing in childhood and the difficulties in differentiating vascular disorders from acrodermatitis chronica atrophicans on the basis of the clinical appearance alone.

Background: Rituximab is a genetically engineered antibody directed against the CD20 antigen. Intravenous administration of rituximab has been used for the treatment of patients with low-, intermediate-, and high-grade B-cell non-Hodgkin's lymphomas and is a registered treatment modality for this indication. Treatment of primary cutaneous B-cell lymphoma (CBCL) with intralesionally or systemically administered rituximab has been described only in a few cases., Objective: Our purpose was to assess the efficacy of rituximab in the treatment of CBCL., Methods: We performed a retrospective study on 9 patients with CBCL who were treated with intralesional or systemic administration of rituximab., Results: Two patients treated with systemic rituximab achieved complete remission. Complete remission could be observed in 6 of 7 patients after 1 to 8 cycles of intralesional treatment with rituximab. In one patient one of two lesions showed a partial remission after 4 cycles of treatment, whereas the second showed complete remission. A local recurrence was observed in one patient after 27 months of follow-up and in two patients recurrences developed at other body sites after 12 and 14 months of follow-up. No severe side effect occurred except for slight pain during intralesional injection., Conclusion: Rituximab therapy is a well-tolerated and effective treatment for primary CBCL. In comparison to intravenous administration, intralesional application of the drug allows the use of lower dosages. Intralesional therapy with rituximab deserves further investigation and comparison to systemic administration of the drug in controlled multicenter studies.

Background: Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma. In early stages of the disease many different clinicopathologic variants have been observed., Observation: We report 6 patients with early manifestations of MF characterized by the sole presence of papules which, unlike the papules of lymphomatoid papulosis, did not show a tendency for spontaneous resolution. Histologic examination confirmed the diagnosis of MF in all cases. Immunohistochemical staining for CD30 was negative in all cases. Follow-up data showed the nonaggressive behavior of the disease, confirming that the lesions were not manifestations of advanced MF., Conclusion: Papular MF is a new variant of early MF characterized by the presence of papules in the absence of more conventional early lesions (patches) of the disease. This variant should be added to the long list of clinicopathologic subtypes of MF.

Background: The carcinogenic potential of 8-methoxypsoralen photochemotherapy (psoralen-UVA [PUVA]) is correlated with the total number of treatments and cumulative UVA dose applied during oral PUVA therapy., Objective: We sought to determine whether reducing treatment frequency and UVA dose affects the therapeutic efficacy of oral PUVA for patients with chronic plaque psoriasis., Methods: This was a prospective, randomized, half-side study performed in a photodermatology department in a dermatology hospital. Eighteen consecutive patients with chronic plaque psoriasis received paired PUVA regimens (0.5 minimal phototoxic dose [MPD] 4 times/wk vs 1 MPD twice/wk, 0.5 MPD twice/wk vs 1 MPD twice/wk, and 0.5 MPD twice/wk vs 0.75 MPD twice/wk). The PUVA regimens were assessed for reduction of Psoriasis Area and Severity Index (PASI) score and the number of treatments and cumulative UVA dose required to reduce PASI score to defined end points (ie, PASI reductions of 25%, 50%, and 75%) or to induce complete remission (PASI < 3)., Results: Reducing the number of treatments while maintaining the same UVA dose per week did not reduce overall therapeutic efficacy. Reducing the number of treatments to twice a week and reducing the UVA dose from 1 MPD to 0.75 or 0.5 MPD per treatment only slightly affected intermediate therapeutic efficacy (between the second and seventh weeks of therapy) but had no effect on final clearance rates. The time to complete clearance did not significantly differ between regimens. The mean cumulative UVA dose was significantly lower for the least intensive dose regimen (0.5 MPD twice/wk) than for the more intensive regimens., Conclusions: Reducing treatment frequency and UVA dose does not substantially compromise the therapeutic efficacy of PUVA.

Background: Benign pigmented lesions of the genitalia, such as genital lentigines and melanocytic nevi, often show clinical and histopathologic features highly suggestive of malignant melanoma (MM). Superimposed changes of lichen sclerosus (LS) may cause real concern and lead to an erroneous diagnosis of MM., Objective: This study was performed to assess clinicopathologic characteristics of genital lentigines and melanocytic nevi with associated LS., Methods: We performed a retrospective review of 5 cases., Results: Histopathologic sections of the 2 cases of genital lentigines with concurrent changes of LS showed a lichenoid lymphocytic infiltrate and pigment incontinence with melanophages in a fibrosed papillary dermis, features reminiscent of completely regressed MM. The 3 cases of genital melanocytic nevi and superimposed LS were sharply circumscribed, relatively symmetric, but revealed confluent nests varying in size and shape and pagetoid upward spread of melanocytic nests and single melanocytes. Changes of LS extended beyond the melanocytic proliferation., Conclusion: Genital lentigines and melanocytic nevi with associated LS may show features that mimic MM.

Various exogenous factors (eg, drugs, dietary antigens, trauma, infections, radiographs, and UV radiation) are known to induce or aggravate skin diseases. UV radiation in particular is known to induce or aggravate the autoimmune bullous diseases of pemphigus foliaceus, pemphigus vulgaris, and bullous pemphigoid. Its role in linear IgA dermatosis, however, is not well recognized. We report the second case of linear IgA dermatosis induced by intense sun exposure in which blistering was induced by UVA radiation. Furthermore, a review of the literature on photoinduced autoimmune bullous diseases and the wavelengths responsible for the induction of blistering is presented and several proposed mechanisms of action for the blister induction, including release or unmasking of antigens, promotion of antibody fixation by UV radiation, and launching of an inflammatory process, are discussed. We conclude that linear IgA dermatosis should be added to the list of autoimmune bullous diseases induced and/or aggravated by UV radiation.

We report an unusual case of congenital melanocytic nevus presenting in a 19-year-old African woman as widespread papules and variably sized nodules and tumors affecting the entire body, including the palms, soles, and oral mucous membrane. Histopathologic examination of 3 representative skin lesions showed mainly dermal aggregations of round to oval, focally pigmented, monomorphous melanocytes, arranged in nodular and plexiform patterns. Scattered areas with spindle-shaped dendritic melanocytes surrounded by fibrosis were also noted in the center of the lesions. The clinical and histopathologic findings were similar to those in 2 other previously reported cases, except that in 1 of the earlier cases the skin nodules were composed of spindle-shaped cells, suggesting a type of blue nevus. The findings in our case indicate a broader spectrum of morphologic features in this condition, with dermal aggregations of melanocytes showing congenital features, representing a common histopathologic denominator. Based on this observation, we suggest the term "widespread congenital dermal nevus with large nodules" to be the most appropriate for this rare, but distinctive, type of congenital nevus.

Background: Hypopigmented mycosis fungoides (MF) is a rare variant of cutaneous T-cell lymphoma. It is more frequent in dark-skinned or Asian patients, particularly children. Only 9 cases in Caucasian patients have been reported in the literature so far., Observation: We describe 7 Caucasian patients (2 children and 5 adults) with hypopigmented MF. Histologic examination confirmed the diagnosis in all cases. The phenotype of neoplastic lymphocytes was T helper in 4 cases and T suppressor in 3 (2 of them children). Monoclonality of the T lymphocytes could be detected in hypopigmented lesions in all 7 cases with the use of a polymerase chain reaction technique. In 4 patients, polymerase chain reaction analysis of T-cell receptor-gene rearrangement after laser-based microdissection of the specimen revealed that the monoclonal population of T lymphocytes was confined mainly to the epidermis., Conclusion: Hypopigmented lesions of MF can be observed in Caucasian patients. Children affected by MF often present with this rare clinical variant of the disease. Persistent or unusual hypopigmented lesions should be subjected to biopsy to avoid delay in the diagnosis of MF, especially in children.

Background: There is a need for better standardization of the dermoscopic terminology in assessing pigmented skin lesions., Objective: The virtual Consensus Net Meeting on Dermoscopy was organized to investigate reproducibility and validity of the various features and diagnostic algorithms., Methods: Dermoscopic images of 108 lesions were evaluated via the Internet by 40 experienced dermoscopists using a 2-step diagnostic procedure. The first-step algorithm distinguished melanocytic versus nonmelanocytic lesions. The second step in the diagnostic procedure used 4 algorithms (pattern analysis, ABCD rule, Menzies method, and 7-point checklist) to distinguish melanoma versus benign melanocytic lesions. kappa Values, log odds ratios, sensitivity, specificity, and positive likelihood ratios were estimated for all diagnostic algorithms and dermoscopic features., Results: Interobserver agreement was fair to good for all diagnostic methods, but it was poor for the majority of dermoscopic criteria. Intraobserver agreement was good to excellent for all algorithms and features considered. Pattern analysis allowed the best diagnostic performance (positive likelihood ratio: 5.1), whereas alternative algorithms revealed comparable sensitivity but less specificity. Interobserver agreement on management decisions made by dermoscopy was fairly good (mean kappa value: 0.53)., Conclusion: The virtual Consensus Net Meeting on Dermoscopy represents a valid tool for better standardization of the dermoscopic terminology and, moreover, opens up a new territory for diagnosing and managing pigmented skin lesions.

Background: The clinicopathologic spectrum of warty dyskeratoma (WD) is not well characterized and the pathogenesis of this unusual lesion is still unclear., Objective: We reviewed the clinical and histopathologic spectrum of WD and investigated a possible involvement of human papillomavirus (HPV) infection in onset of this lesion., Methods: A total of 46 cases of WD were analyzed clinically and histopathologically. Polymerase chain reaction (PCR) analysis for HPV-DNA was performed in 13 lesions of WD., Results: A total of 46 lesions of WD from 45 patients (M/F ratio, 1:1.8; mean age 59.8 years, median 61 years, age range 3-88 years) presented as solitary papules or small nodules on the head and neck (32 cases), trunk (9 cases), lower extremities (4 cases), and upper extremities (1 case). One patient had 2 lesions. No patient had clinical signs of Darier's or Grover's disease. Histopathologically on scanning magnification, lesions showed mainly 3 architectural patterns, namely, cup-shaped (29 cases), cystic (6 cases), and nodular (2 cases). In 9 cases, a combination of two of these morphologic patterns was observed. Characteristically, the epithelial component in all WDs displayed foci of acantholytic dyskeratosis. Variable features suggestive of follicular differentiation toward the infundibular portion of a normal hair follicle were also observed, including a focal contiguity to pilosebaceous units in most cases (63%), and the presence of small infundibular cystic structures in a subset of lesions (46%). The majority of lesions (83%) also revealed a hyalinized or fibrous stroma with intrastromal clefts. PCR analysis for HPV-DNA performed in 13 cases inclusive of all representative architectural patterns was negative., Conclusion: We conclude that WD shows a wider spectrum of morphologic features than previously recognized. Despite some histopathologic similarities to viral warts, WD is not a manifestation of HPV infection. On the other hand, the majority of these lesions display overall histopathologic features consistent with a follicular adnexal neoplasm. On the basis of this finding, we propose the alternative term follicular dyskeratoma to better reflect the distinctive features of this peculiar lesion.

Oil of bergamot is an extract from the rind of bergamot orange (Citrus aurantium ssp bergamia) that has a pleasant, refreshing scent; until a few years ago it had been widely used as an ingredient in cosmetics but was restricted or banned in most countries because of certain adverse effects. More recently, oil of bergamot preparations have been gaining renewed popularity in aromatherapy. Oil of bergamot possesses photosensitive and melanogenic properties because of the presence of furocoumarins, primarily bergapten (5-methoxypsoralen [5-MOP]). However, 5-MOP is also potentially phototoxic and photomutagenic. Despite its increasing application, there are only a few recent reports of phototoxic reactions to bergamot aromatherapy oil. We describe two patients with localized and disseminated bullous phototoxic skin reactions developing within 48 to 72 hours after exposure to bergamot aromatherapy oil and subsequent ultraviolet exposure. One patient (case 2) had no history of direct contact with aromatherapy oil but developed bullous skin lesions after exposure to aerosolized (evaporated) aromatherapy oil in a sauna and subsequent UVA radiation in a tanning salon. This report highlights the potential health hazard related to the increasing use of psoralen-containing aromatherapy oils.

Cutaneous immunocytomas are low-grade malignant B-cell lymphomas that arise in the skin as solitary or multiple papules, plaques, or nodules. We describe a female patient with lymphoplasmocytic lymphoma who presented with multiple, brown-red to bluish macules and papules on the left thigh. The proliferation was monoclonal as evaluated by positive staining of the plasma cells with antibodies against IgG heavy chain and lambda-light chain and with polymerase chain reaction showing immunoglobulin heavy-chain gene rearrangement. Neither paraproteinemia nor involvement of bone marrow was present.

Therapy with medicinal leeches (Hirudo medicinalis) is now frequently applied in plastic surgery and in the management of chronic venous insufficiency. We observed a patient in whom firm, brown-red, pea-sized papules developed at each site where leeches had been applied on the lower legs. Histology, immunohistology, and molecular analysis of T-cell receptor and immunoglobulin heavy chain gene rearrangement proved these lesions to be follicular pseudolymphomas.

The CHILD syndrome (congenital hemidysplasia with ichthyosiform nevus and limb defects) is usually characterized by lateralization of all associated anomalies. It has been assumed that the event of X-inactivation coincides and interferes with a clone of organizer cells controlling a large developmental field. A 16-year-old girl with bilateral manifestations of CHILD syndrome is described. The inflammatory skin lesions affected the body folds (ptychotropism) in a symmetrical distribution, although only the right side of the neck was involved. In addition, absence of several facial muscles, vertebral defects, and shortening of the leg on the right side were noted, and a ventricular septum defect was present. This unusual case may be explained by the assumption that X-inactivation did not coincide with the origin of inducer cell clones controlling large morphogenetic fields on either side of the body.

Background: Overexpression of adhesion molecules in tissues of human neoplasms, including malignant melanoma, has been reported to be clinically relevant, but the predictive value of circulating adhesion molecules for clinical outcome and life expectancy in patients with primary malignant melanoma (PMM) and metastases of primary malignant melanoma (MMM) remains undetermined., Objective: Our purpose was to examine the prognostic relevance of circulating adhesion molecules, namely circulating CD44 standard (cCD44std), and the isoforms CD44v5 (cv5), CD44v6 (cv6), and CD44v10(cv10), circulating intercellular adhesion molecule-1 (cICAM-1), and circulating platelet/endothelial cell adhesion molecule-1 (cPECAM-1, CD31)., Methods: Levels of cCD44std, cv5, cv6, cv10, cICAM-1, and PECAM-1 were measured by enzyme-linked immunosorbent assays in 119 patients with PMM and MMM, in 12 persons with dysplastic nevi (Clark's nevi), and in 28 patients with inflammatory cutaneous diseases., Results: Patients with PMM, MMM, and inflammatory cutaneous diseases showed an elevation in levels of cCD44std and cICAM-1 compared with normal blood donors, but these levels were not significantly increased. Levels of cv5, cv6, and cv10 were not increased, and cPECAM-1 was only marginally elevated. Even in patients with clinically provable systemic or cutaneous metastases and in five patients who died of MMM, levels did not differ significantly compared with normal blood donors; this was also independent of the mode of therapy., Conclusion: Circulating CD44std and the isoforms cv5, cv6, and cv10, cICAM-1, and cPECAM-1 were detectable in persons with dysplastic nevi and in patients with PMM and MMM. None of the measured adhesion molecules was significantly elevated and of prognostic relevance in any of the subgroups studied. However, some of the patients with PMM and MMM showed high levels of cCD44std and cICAM-1; that finding should prompt us to examine these patients in more detail.

We describe a 53-year-old HIV-negative white man who had chronic CD4+ T lymphocytopenia and photoaccentuated erythroderma with lymphoma-like histologic changes. The erythroderma completely responded to 5-methoxypsoralen and UVA (PUVA), interferon alfa-2b, and extracorporeal photopheresis. During therapy opportunistic skin infections, including tinea corporis, warts, and disseminated molluscum contagiosum, developed. Although the patient met the current definition of idiopathic CD4+ T lymphocytopenia (ICTL), we cannot rule out the possibility that this peripheral CD4+ T lymphocytopenia resulted from sequestration of CD4+ T lymphocytes in erythrodermic skin.

Nevoid basal cell carcinoma (BCC) syndrome is a genetically linked disorder characterized by multiple BCCs associated with various skeletal abnormalities and sometimes with mental retardation. Because of the large number of lesions, treatment of BCCs in these patients may be extremely difficult. The value of different therapeutic options was assessed in a patient with multiple, disfiguring nevoid BCC syndrome. Surgical excision and split-skin grafting was used to remove three larger tumors. Photodynamic therapy led to healing of flat lesions; small papules within the treated areas, however, did not respond to this type of management. Three nodular BCCs treated with intralesional application of interferon alfa-2b were markedly reduced in size. Still, complete healing could not be achieved. Nodular lesions vaporized with the CO2 laser disappeared and showed no recurrence after 2 years of follow up. Our experience indicates that CO2 laser vaporization of BCCs allows the treatment of a large number of lesions in a single session, and is indicated when surgical treatment is not feasible for all lesions. Photodynamic therapy with 5-amino-levulinic acid may be a valid therapeutic option for flat lesions only. Intralesional application of interferon alfa-2b removes papular lesions of small size.

Background: High-resolution sonographic measurement of skin tumors, especially of malignant melanomas, allows presurgical assessment of the most important prognostic factor--tumor thickness. A good correlation between ultrasonographic and histopathologic thickness measurement has been reported. Procedures for preparing tissue for histopathologic examination, such as excision, fixation in formalin, dehydration in alcohol, and embedding in paraffin, may cause the tissue to retract and shrink and may therefore affect thickness measurement results., Objective: Our purpose was to evaluate the influence of skin preparation procedures on ultrasound measurement results and to compare tumor thickness values obtained sonographically versus those obtained histopathologically., Methods: Sixty-three epithelial (n = 37) and melanocytic (n = 26) tumors, benign as well as malignant, were measured by ultrasound before and immediately after excision and after overnight fixation. Sonographically and histopathologically determined tumor thicknesses were compared., Results: Loss of skin tension after excision led to an increase in measured tumor thickness because of spherical retraction of the specimen. Subsequent fixation, dehydration, and embedding reversed this effect, so that altogether, histopathologically assessed tumor thickness was only slightly lower than ultrasound-derived thickness before excision. This was true for melanocytic as well as epithelial lesions., Conclusion: Loss of skin tension after excision and tissue preparation procedures seem to offset each other and lead to a good overall correlation between ultrasonographic and histopathologic measurements.

Filiform hyperkeratosis of the palms and soles is a rare disorder. We describe a 70-year-old man with a 2-year history of multiple, filiform, keratotic projections on the palms and a nodular malignant melanoma on the back. Histopathologic examination of the palmar lesions revealed that each single keratotic projection was composed of a well-defined, compact parakeratotic column. The underlying epidermis showed a thinned granular layer. Five other cases of palmoplantar filiform hyperkeratosis in association with malignant neoplasms have been reported. Filiform hyperkeratosis of the palms and soles may represent a distinct paraneoplastic condition.

Background: Topical photodynamic therapy with endogenous porphyrins consists of irradiation of a tumor with visible light after the application of exogenous 5-aminolevulinic acid., Objective: To assess the effectiveness of this modality, patients with precancerous conditions and various skin cancers were treated., Methods: Thirteen patients with 70 skin lesions were enrolled. Standard treatment involved the topical application of 20% 5-aminolevulinic acid in an oil-in-water emulsion. The emulsion was applied under an occlusive dressing for 4 to 8 hours before exposure to photoactivating light., Results: We observed a complete response after a single treatment for all 9 solar keratoses, 5 of 6 early invasive squamous cell carcinomas, and 36 of 37 superficial basal cell carcinomas. Only 1 of 10 nodulo-ulcerative basal cell carcinomas completely resolved. Eight cutaneous metastases of malignant melanoma were therapeutic failures., Conclusion: Topical photodynamic therapy with endogenous porphyrins is effective for superficial epithelial skin tumors.

The occurrence of lymphomatoid papulosis in patients with cutaneous lymphoma, particularly mycosis fungoides, has been described in medical literature. A 68-year-old woman affected by mycosis fungoides in the plaque stage noticed that multiple papulonodular lesions of lymphomatoid papulosis developed suddenly after a few sessions of PUVA therapy. The PUVA induction of lymphomatoid papulosis was confirmed by the appearance of new lesions after a second cycle of PUVA exposure on a limited area of the body. Complete regression of all PUVA-induced lymphomatoid papulosis lesions was achieved within a few weeks with oral prednisone and topical steroids. During the entire treatment the patches and plaques of mycosis fungoides persisted unchanged.

Four cases of large eccrine acrospiroma (three benign, one malignant) are reported. The benign tumors involved the lower extremities of two women and one man (73 to 89 years of age). The duration of the lesions ranged from 10 to 20 years. The malignant tumor involved the left side of the chest of a 60-year-old man. Its occurrence in a lesion that had been present for 40 years suggested malignant transformation of a pre-existing benign eccrine acrospiroma. Each tumor showed little to no cellular atypia. Mitotic rates (mitotic figures per 10 high-power fields) varied both between and within lesions. Average mitotic rates did not differentiate the benign from the malignant tumors. The most important distinguishing features of large benign eccrine acrospiromas are the relative circumscription, the lack of cellular atypia, and the absence of stromal, perineurial, and angiolymphatic invasion.

A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections was compared with a panel of antibodies reactive in frozen sections for the immunophenotyping of cutaneous lymphoproliferative disorders. Three T cell-associated markers (UCHL1, MT-1, MT-2, six B cell-associated markers (MB-1, MB-2, LN-1, LN-2, L-26, 4KB5), immunoglobulin heavy and light chains, anti-LCA antibody, two markers for Reed-Sternberg cells (Ber-H2, Leu-M1), one marker for macrophages (Mac-387) and anti-S-100 protein antibody were tested on normal skin, inflammatory skin diseases, and cutaneous lymphomas and pseudolymphomas. On the basis of the results in frozen sections, 12 inflammatory T cell diseases, 14 T cell lymphomas and pseudolymphomas, and 10 B cell lymphomas and pseudolymphomas were identified. In addition, two cases of specific skin infiltrates of Hodgkin's disease have been examined. Among T cell markers, the greatest sensitivity was exhibited by UCHL1, which stained all but one specimen of T cell infiltrate; it was negative in one specimen of mycosis fungoides that progressed into a T-immunoblastic lymphoma. The combined use of MB-2, LN-2, and 4KB5 identified all B cell proliferations. LN-1 marked germinal centers in all cases of follicular lymphoma and pseudolymphoma. Ber-H2 stained the Reed-Sternberg cells in both cases of Hodgkin's disease and the large cells in the histiocytic type of lymphomatoid papulosis. Mac-387 and anti-S-100 protein antibody recognized macrophages and T-zone histiocytes (Langerhans cells and interdigitating cells), respectively. A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections is proposed that facilitates the identification of most B and T cell infiltrates in the skin.