Evidence against a role for human T-cell lymphotrophic virus type I (HTLV-I) in the pathogenesis of American cutaneous T-cell lymphoma.

We used a standard polymerase chain reaction (PCR)/Southern blot assay (sensitivity > 10(-5)) to detect human T-cell lymphotrophic virus type I (HTLV-I) proviral pX, pol, and env genes in the lesional skin of 42 American patients with cutaneous T-cell lymphoma (CTCL). As in some prior reports using similar methods, a variable proportion of PCR tests were positive (seven of 42 for pX, three of 42 for pol, and two of 37 for env), resulting in an overall positive test rate of 12 of 121 (10%). To determine the significance of these positive test results, we performed several additional studies. D1S80 polymorphism analysis of CTCL cases and HTLV-I PCR analysis of non-CTCL dermatosis controls showed no evidence that positive PCR tests resulted from sample mislabeling, gross HTLV-I contamination, or human endogenous retroviruses. We then modified the standard PCR assay to incorporate ultraviolet (UV) light to destroy low-level PCR contamination. With this modified assay (sensitivity > 10(-5)), only three of 12 previously positive cases were still positive, suggesting that the earlier positives were due to trace contamination of PCR reagents or trace contamination of sample DNA. This interpretation was also supported by: (i) a match between pX and pol sequences cloned from one PCR-positive specimen and the MT4-positive control, (ii) our inability to confirm HTLV-I in any PCR-positive case using genomic dot blotting (sensitivity > 10(-2)), and (iii) negative PCR results when new samples from two of the remaining positive cases were analyzed. Finally, we used our modified UV/ PCR/Southern blot assay to test an additional 28 cases of American CTCL for pX. All of them were negative. Although these studies of 70 cases of American CTCL do not exclude the possibility that another virus is involved in the pathogenesis of this disease, they provide strong evidence against a role for HTLV-I. Furthermore, they emphasize the need for special strategies to control for false-positive PCR tests that can result from even trace levels of contamination with viral DNA. As a consequence, associations between diseases and viruses should be viewed skeptically if they are based primarily on conventional PCR data.

HMB-45 staining of dysplastic nevi. Support for a spectrum of progression toward melanoma.

Dysplastic nevi are melanocytic tumors that occupy intermediate positions in the spectrum of melanocytic proliferations. Although they are invariably cured if completely excised, their biologic potential if left untreated is unknown. We examined a series of such lesions with HMB-45, a melanocyte-specific antibody, in order to explore protein expression within these borderline lesions. HMB-45 has previously been shown to label intraepidermal melanocytes within melanomas and within all nevi. Intradermal melanoma cells also label with HMB-45, but dermal nevus cells within common melanocytic nevi do not normally stain. In contrast, we found mild to moderate staining of nevus cells within the papillary dermis of dysplastic nevi and within residual nevus cells adjacent to malignant melanomas. In the same lesions, we demonstrated strong staining of intraepidermal melanocytes. Thus, dermal nevus cells within dysplastic nevi and within residual nevus cells adjacent to malignant melanomas are expressing low-level amounts of a protein expressed by melanoma cells, but not by dermal nevus cells within wholly benign melanocytic tumors. This lends support to the concept of these lesions as precursor lesions with undetermined biologic potential.

Value of skin biopsies in assessing prognosis and progression of acute graft-versus-host disease.

Skin biopsies are commonly performed after allogeneic bone marrow transplantation (BMT) to help establish the origin of a new skin rash in a transplant recipient. Histologic criteria and a grading system for acute graft-versus-host reaction of the skin are well established. Histologic diagnosis, however, can be difficult and is based on interpretation of subtle changes that show significant overlap with features seen in other entities that can be responsible for a skin rash in the posttransplantation period such as drug reactions, viral exanthems, and the effects of chemotherapy. We retrospectively reviewed 179 skin biopsies from 137 patients who had undergone allogeneic BMT. We compared 98 skin biopsies from 71 patients with acute graft-versus-host disease (GvHD) with 81 biopsies from 66 patients who underwent biopsy to exclude GvHD but did not go on to develop the disease on clinical grounds. Two observers reviewed each slide without knowledge of the clinical situation and graded 16 histologic parameters. No single parameter (e.g., dyskeratotic keratinocytes, basal vacuolization, satellitosis, necrotic cells in appendages) achieved statistical significance on univariate analysis. A search for factors to separate GvHD biopsies from non-GvHD biopsies using logistic regression failed to reveal a single best predictor or a combination of predictors. We conclude that skin biopsies after allogeneic BMT are of limited use in predicting the progression of a skin rash to clinical grade II or higher GvHD.

Atypical fibroxanthoma. Multiple immunohistologic profiles.

The clinical, histologic, and immunohistochemical features of 37 cases of atypical fibroxanthoma (AFX) are presented. Patients ranged in age from 13 to 95 years (mean, 69). Thirty AFXs occurred on the head and neck, and seven lesions developed on the trunk or extremities. The morphologic spectrum varied from a predominant spindle cell pattern with focal cellular pleomorphism to numerous bizarre epithelioid cells with multinucleated giant cells. The spindle cell component in these lesions ranged from 10 to 90% of the constituent cells. Most (31 of 37) AFXs also contained pleomorphic giant cells. Small numbers of S-100-positive dendritic cells were present in 11 cases. Five cases showed variable reactivity with anti-factor-XIIIa. Fifteen (41%) of the AFXs stained for muscle-specific actin or smooth muscle actin and 21 (57%) expressed CD68 (detected with monoclonal KP1), a monocyte-macrophage marker. Reactivity for these antigens was seen in all lesional cell types (spindled, epithelioid, and bizarre). Four immunologic profiles were observed: CD68 only (13 cases), actin only (7 cases), double positives (8 cases), and double negatives (9 cases). No significant differences in staining characteristics were observed in the head and neck versus the trunk and extremity lesions. These results expand the immunohistochemical spectrum of AFX, suggest the concept of heterogenous bimodal "fibrohistiocytic" and "myofibroblastic" phenotypes, and provide further evidence that an integrative, nonalgorithmic approach is necessary in the analysis of these and other spindle cell cutaneous lesions.

Reassessment of histologic parameters in the diagnosis of mycosis fungoides.

The histologic diagnosis of mycosis fungoides (MF) can be difficult to establish and is based on interpretation of numerous subtle changes, most of which may be present to some degree in many inflammatory and neoplastic cutaneous conditions. To reassess the diagnostic criteria for making a histologic diagnosis of MF, we retrospectively reviewed histologic sections from 64 patients with mycosis fungoides (MF+) and compared the findings with sections from 47 patients who were biopsied to exclude MF and were shown not to have the disease (MF-). Patients were selected as MF+ or MF- independent of histologic findings based on the clinical course with at least 3 years of follow-up and immunophenotyping results. Following patient selection, at least two observers reviewed each slide without knowledge of final diagnosis and graded the intensity of approximately 25 histologic parameters. On univariate analysis, the following parameters were significant at beyond the p = 0.01 level: Pautrier's abscesses, haloed lymphocytes, exocytosis, disproportionate epidermotropism, epidermal lymphocytes larger than dermal lymphocytes, hyperconvoluted intraepidermal lymphocytes, and lymphocytes aligned within the basal layer. Haloed lymphocytes proved to be the most robust discriminator of MF from non-MF on multivariate analysis. These findings show that whereas many previously described features do discriminate between MF and inflammatory mimics, others are much less specific. Furthermore, few cases demonstrate all histologic features; for example, Pautrier's microabscesses were seen in only 37.5% of our cases. We conclude that a combination of specific histologic parameters can be used to establish a microscopic diagnosis of MF without the necessity of confirmatory immunophenotyping in the vast majority of cases.

Aggressive cutaneous NK and NK-like T-cell lymphomas: clinicopathologic, immunohistochemical, and molecular analyses of 12 cases.

Natural killer (NK) and NK-like T-cell lymphomas are rare hematolymphoid malignancies that predominate in the upper aerodigestive system. They also involve other extranodal sites, including the skin. Primary cutaneous manifestations of NK and NK-like T-cell lymphomas are uncommon, and the clinicopathologic features are poorly understood. We have studied 12 patients of varied ethnic backgrounds with CD56-positive lymphomas in the skin. Six patients subsequently progressed to disseminated disease. These lymphomas showed the following immunophenotype: CD56+, CD43+, TCRb-, CD3-/+, CD20-, CD30-/+, CD4-, and CD8-. Two cases exhibited T-cell receptor gene rearrangements supporting a T-cell origin for these lymphomas, whereas the remaining 10 cases were likely derived from NK cells. Our results show inconsistent association of these lymphomas with Epstein-Barr virus (EBV), the multidrug resistance phenotype, and expression of P53. In addition, we found a previously unreported correlation between lymphomas harboring EBV mRNA and the expression of the multidrug resistance phenotype. These lymphomas were aggressive and were associated with rapid clinical progression, treatment failure, multiple relapses, and an average survival of 15 months from the time of diagnosis. Our results indicate the importance of recognizing this disease as a distinct subset of aggressive cutaneous lymphomas that may be diagnosed on the basis of morphology, immunophenotype, and gene rearrangement studies.

Bloodless glucose measurements.

Self-measurement of blood glucose is part of the daily routine for patients with diabetes, and healthcare professionals use these values for therapy and treatment. Healthcare providers are encouraging patients with insulin-dependent diabetes to test their blood glucose level four to six times a day to effectively manage their disease and significantly reduce the incidence of serious and costly complications. Unfortunately, people with diabetes test less than once a day on average, associating this noncompliance with pain associated with drawing blood from the finger. Glucose-monitoring techniques are under study that would allow body fluids other than blood to be used in a painless or almost painless manner. These new technologies could lead to a revolutionary advance in the treatment of diabetes, and the current research and development can now be reviewed.

Leukemia cutis. Analysis of 50 biopsy-proven cases with an emphasis on occurrence in myelodysplastic syndromes.

The hematologic, cytomorphologic, and cytogenetic features of 50 cases of leukemia cutis (LC), occurring in 40 patients, are presented. The patients' ages ranged from 19 to 75 years (mean, 42 years). The primary hematologic diagnoses in these patients included acute non-lymphoblastic leukemia (ANLL), 13 patients; myelodysplastic syndrome (MDS), 19 patients; chronic lymphocytic leukemia, 3 patients; chronic granulocytic leukemia, 3 patients; and polycythemia vera, 1 patient. Leukemia cutis developed in one patient without any known prior or subsequent hematologic disorder. The 13 cases of ANLL included French-American-British types M1 (1 case), M2 (5 cases), M3 (1 case), M4 (5 cases), and M5 (1 case). Leukemia cutis preceded blood and/or bone marrow manifestations of leukemia in nine patients with MDS and one with ANLL. The interval from skin biopsy to systemic leukemia ranged from 3 weeks to 20 months (mean, 6 months). In seven patients with MDS and three patients with ANLL, LC occurred concomitantly with leukemic transformation. Only two patients with MDS and LC did not have progression to acute leukemia during the 20 and 24 months they have been observed. Diagnoses other than LC initially were considered in five of the patients. LC was characterized most often by a dense mixed cellular dermal infiltrate that circumscribed vascular and adnexal structures. Nine patients with MDS (47%) and one with ANLL (8%) had complex chromosomal abnormalities in their bone marrow samples at the time of LC. This article reports the occurrence of LC in patients with MDS and suggests that LC is an early manifestation of leukemic transformation in these patients. These results may be important in identifying high-risk patients for early interventional therapy.

Reducing adult phlebotomy blood loss with the use of pediatric-sized blood collection tubes.

The feasibility of collecting smaller blood volumes during phlebotomy for diagnostic laboratory testing was evaluated by substituting pediatric-size for adult-size blood collection tubes. The volume of blood drawn with the use of pediatric-size tubes from 41 patients in an intensive care unit (120.2 mL total; 32.2 mL/day) was 46.8% lower than in that of a control population for which adult-size tubes were used (226.1 mL total; 55.6 mL/day). Sufficient blood was available for performance of all laboratory tests ordered at the time of the phlebotomy. Although substituting pediatric-size tubes does not address the problem of excessive use of laboratory tests, smaller tubes may reduce the severity of phlebotomy-induced anemia in adults without compromising laboratory test procedures.

Port-wine stains. A disease of altered neural modulation of blood vessels?

Port-wine stains result from a progressive ectasia of the cutaneous superficial vascular plexus. One hypothesis for the pathogenesis of this lesion is an abnormal neural regulation of blood flow. Biopsy specimens of 11 port-wine stains, seven hemangiomas, and 17 benign lesions were stained for S100 protein using immunoperoxidase techniques. All specimens were of facial biopsies or excisions and were evaluated for vessels per square millimeter, nerves per square millimeter, vessel-to-nerve ratio, and frequency of vessels coursing within 0.03 mm of nerves. These variables were evaluated in the superficial 0.8 mm of dermis, a zone that includes almost all abnormal port-wine-stain vessels. Controls showed 18.3 +/- 2.8 vessels/sq mm (+/- SD), 21.1 +/- 9.2 nerves/sq mm, 0.9 +/- 0.3 vessels to nerves, and 75% +/- 11% of vessels coursing within 0.03 mm of nerves, values that did not alter with age. Port-wine stains had a significant decrease in nerve density and increase in vessel-to-nerve ratio when compared with normal skin; only 17% +/- 3% of vessels were associated with nerves in port-wine stains. These findings document a deficit in the number of perivascular nerves in port-wine stains and raise the possibility that a lack of neural modulation of vascular flow may be involved in the pathogenesis of port-wine stains.

A case of Woringer-Kolopp disease with Ki-1 (CD30) + cytotoxic/suppressor cells.

BACKGROUND: Woringer-Kolopp (W-K) disease is a rare, localized, histologically malignant, but clinically indolent lymphoproliferative disorder. Most authors have regarded W-K disease as a variant of mycosis fungoides. However, a recent case suggests that W-K disease may represent a spectrum of lymphoproliferative disorders that may not be related to mycosis fungoides. OBSERVATIONS: A patient with a 40-year history of localized cutaneous eruption characterized by markedly atypical epidermotropic lymphocytes was seen at Stanford (Calif) University Hospital. The lymphocytes were predominantly CD30+ cytotoxic/suppressor T cells, an immunophenotype not previously described in W-K disease. Genotype analysis revealed a clonal rearrangement. CONCLUSIONS: The findings in our patient, along with a review of all cases previously reported in the literature, suggest that W-K disease may be an entity with a uniform clinical and histologic presentation, but one with marked immunophenotypic heterogeneity of the malignant-appearing atypical cells. Some cases showed immunophenotypic similarities to mycosis fungoides. However, in almost half of the reviewed cases, including the one presented here, the immunophenotypic differences exceeded the similarities.

The natural history of vasculitis. What the histology tells us about pathogenesis.

While histopathologic analysis may offer some clues as to the pathogenesis of vasculitis, observations must be interpreted with caution, as there is considerable overlap in the histologic pattern. In most cases, a predominantly neutrophilic vasculitis affecting small dermal venules suggests a relatively acute, immune complex-mediated reaction. Less commonly, this histologic pattern may be seen in non-immunologically mediated processes, such as in the presence of bacterial toxins or malignant hypertension, or in more chronic disease states, such as granuloma faciale or erythema elevatum diutinum. A predominantly lymphocytic vasculitis may represent several pathogenetic mechanisms. In lesions more than 24 to 48 hours old, a lymphocytic vasculitis may represent a resolving phase of an immune complex-mediated neutrophilic vasculitis. Alternatively, this histologic pattern may be seen de novo in conditions with a presumed cell-mediated immunologic pathogenesis. Lymphocytic vasculitis may also be seen in rickettsial infections such as Rocky Mountain spotted fever. The pathogenesis of granulomatous vasculitis remains poorly understood and is thought to be induced by a combination of circulating immune complexes and a cell-mediated immune response.

Benign cutaneous polyarteritis nodosa. Relationship to systemic polyarteritis nodosa and to hepatitis B infection.

Benign cutaneous polyarteritis nodosa has been described as having a benign course in contrast to that of systemic classic polyarteritis nodosa. We tested the hypothesis that this histologic distinction is false by reviewing nine consecutive cases with the histologic diagnosis of benign cutaneous polyarteritis nodosa. Our study revealed that on follow-up, seven (78%) of nine cases had evidence of involvement of at least one organ other than the skin, with the kidney being the organ most commonly involved. Four (44%) of nine patients had serologic evidence of hepatitis B infection, one had cryoglobulinemia, and one had polyclonal hypergammaglobulinemia associated with acquired immunodeficiency syndrome. We conclude that benign cutaneous polyarteritis nodosa is not necessarily benign and is closely related to systemic polyarteritis nodosa.

Immunohistochemical demonstration of factor XIIIa expression in neurofibromas. A practical means of differentiating these tumors from neurotized melanocytic nevi and schwannomas.

Neurofibromas, schwannomas, and neurotized melanocytic nevi may closely resemble one another at the light microscopic level. We studied 10 neurofibromas, 10 schwannomas, and 10 partially neurotized melanocytic nevi immunohistochemically using an antibody directed against factor XIIIa to determine if this antibody might provide a useful method of differentiating these lesions. The cases were also stained with S100 protein. All of the neurofibromas stained intensely for factor XIIIa. The proportion of cells staining within the tumors varied from 30% to 70%. In contrast, none of the schwannomas and neurotized nevi studied demonstrated staining of tumor cells with this antibody. S100 protein was expressed by 100% of neurofibromas, schwannomas, and melanocytic nevi. Our findings suggest that factor XIIIa may provide a reliable and practical means of differentiating cutaneous neurofibromas from neurotized nevi and cutaneous schwannomas. Distinguishing between these different tumor types may be important in some clinical situations, particularly with respect to rendering a diagnosis of von Recklinghausen's neurofibromatosis. The differences in the immunohistochemical profiles of neurofibromas and neurotized nevi support the concept that these tumors are histogenetically distinct, despite their similar histologic appearances.

Differentiation and clonality of lesional lymphocytes in small plaque parapsoriasis.

BACKGROUND: Small plaque parapsoriasis is an idiopathic chronic dermatosis characterized by patches on the trunk and extremities that are often smaller than 5 cm in diameter and that sometimes have a digitate contour. These latter cases are often referred to as digitate dermatosis. Histopathologic examination reveals a mild superficial perivascular lymphocytic infiltrate associated with mild spongiosis and parakeratosis. To characterize this disease more completely, we analyzed the differentiation and clonality of lesional lymphocytes using immunohistologic and molecular biologic methods. OBSERVATIONS: We studied five cases using a frozen-section immunoperoxidase technique. In each case, there was a predominantly CD4+ T-cell infiltrate admixed with CD8+ T cells, Langerhans cells/indeterminate cells, and macrophages. In three cases, the clonality of lesional T cells was studied by denaturing gradient gel electrophoresis of polymerase chain reaction-amplified T-cell receptor-gamma gene rearrangements. Two cases showed a dominant clonal pattern, while one case exhibited a polyclonal pattern. Clinical follow-up disclosed persistent disease in one of the two clonal cases, while lesions in the other clonal case and the polyclonal case gradually resolved. CONCLUSIONS: Our findings indicate that small plaque parapsoriasis is a clinically indolent, histopathologically nonspecific, predominantly CD4+ T-cell-mediated disease that, at least in some cases, contains a dominant T-cell clone. These features put small plaque parapsoriasis into a category with certain other members of the parapsoriasis group, namely, pityriasis lichenoides and lymphomatoid papulosis, which have been shown to be clonal T-cell disorders despite their clinically benign course. It remains to be determined if the dominant T-cell clones identified in some cases of small plaque parapsoriasis can ever be the direct precursors of overt cutaneous T-cell lymphomas.

bcl-2 expression in melanocytic nevi. Insights into the biology of dermal maturation.

BACKGROUND AND DESIGN: Recently, a new category of oncogenes has been discovered that regulate programmed cell death. The bcl-2 oncogene has been found to inhibit cellular death without affecting cellular proliferation. In the skin, bcl-2 expression is limited to cells along the basal cell layer. However, we also noticed that resting melanocytes appeared to express bcl-2. We examined the expression of bcl-2 and its possible role in the biology of benign melanocytic proliferations. Routine paraffin sections of formalin-fixed tissue were labeled with anti-bcl-2 monoclonal antibody, and expression of bcl-2 was detected by a biotin-avidin-immunoperoxidase procedure. RESULTS: We examined 13 congenital, 11 acquired, and six atypical or dysplastic nevi for expression of bcl-2. Expression of bcl-2 was observed in 11 of 13 congenital nevi. All 11 acquired nevi and 6 nevi with architectural disarray and cytologic atypia expressed bcl-2. Both junctional and intradermal melanocytes expressed bcl-2 in a perinuclear and cytoplasmic pattern. Within neurotized areas, bcl-2 became significantly weaker and totally absent. CONCLUSIONS: In mature tissues, bcl-2 expression is quite limited. It appears to be restricted to pluripotential stem cells that serve as a reservoir for tissue that is constantly undergoing renewal, such as the hematopoietic cells and the intestinal mucosa. In the skin, bcl-2 expression has been previously reported to be limited to the epidermal basal cell layer and proliferation zones. Our results indicate that resting melanocytes and melanocytic nevi regularly express bcl-2.

Desipramine-induced blue-gray photosensitive pigmentation.

BACKGROUND: Blue-gray pigmentation of the skin can be elicited by several medications. We report the first case (to our knowledge) of desipramine-induced photosensitive blue-gray pigmentation. OBSERVATIONS: Diffuse blue-gray pigmentation on sun-exposed surfaces was noted in a healthy 48-year-old woman who had been taking desipramine hydrochloride for 8 years. Ultrastructural studies demonstrated the presence of melanin and homogeneous electron-dense material in the dermis. CONCLUSIONS: We conclude that tricyclic antidepressant agents represent another class of medications responsible for blue-gray cutaneous pigmentation.

CD34 staining pattern distinguishes basal cell carcinoma from trichoepithelioma.

BACKGROUND AND DESIGN: Trichoepithelioma is a benign skin tumor with follicular differentiation, which sometimes is difficult to distinguish clinically and histologically from basal cell carcinoma. One of the most helpful differences is the histologic appearance of the stroma. CD34 is an antigen known to stain the spindle-shaped cells located around the middle portion of normal hair follicles. We have stained formalin-fixed, paraffin-embedded sections of 16 trichoepitheliomas and 19 basal cell carcinomas for CD34 (anti-HPCA-1, Becton Dickinson, San Jose, Calif) to detect differences in the staining pattern and to facilitate discrimination of these two types of tumors. RESULTS: The spindle-shaped cells surrounding the islands of trichoepithelioma cells were focally strongly positive for CD34. In all basal cell carcinomas, the spindle-shaped cells surrounding the nests of tumor cells were negative; in these areas only the blood vessels were positive with this antibody. CONCLUSIONS: CD34 staining pattern differentiates between trichoepithelioma and basal cell carcinoma. CD34 stain may be helpful in distinguishing between these two tumors on small punch biopsies or in difficult diagnostic cases.

Restrictive dermopathy. Report of two affected siblings and a review of the literature.

BACKGROUND: Restrictive dermopathy is a lethal genetic disorder consisting of abnormally tight skin, generalized joint contractures, distinctive facies, and pulmonary hypoplasia. Autosomal recessive inheritance has been suggested based on multiply affected siblings and some reports of parental consanguinity. This article describes two siblings with the restrictive dermopathy syndrome and reviews previously reported cases. OBSERVATIONS: Eight other cases have been reported in the literature as restrictive dermopathy. These cases have shared striking similarities in their clinical histories and phenotypes. The skin in these infants has been described as rigid and tense, with skin biopsy specimens showing a thick epidermis, thin dermis, abnormally arranged collagen bundles, and poorly developed appendages. Other prominent features are flexion contractures and craniofacial and pulmonary abnormalities. The genetic and/or developmental defects leading to the restrictive dermopathy syndrome are presently not known. CONCLUSIONS: The restrictive dermopathy syndrome is distinct and is easily differentiated from other congenital diseases such as the icthyoses and also from the clinical conditions of sclerema neonatorum and subcutaneous fat necrosis of the newborn. Recognition of this syndrome is important for determining the prognosis of affected infants and for recommending genetic counseling to affected families.