Interobserver variability in the classification of childhood maculopapular cutaneous mastocytosis.

BACKGROUND: Maculopapular cutaneous mastocytosis (MPCM) in children is classified in two variants: (i) monomorphic variant, presenting with the small macules or papules typically seen in adult patients; and (ii) polymorphic variant with larger lesions of variable size and shape, typically seen in children. The definition of polymorphic and monomorphic variants is mostly intuitive, and a validation of this classification has not been done. OBJECTIVE: To study interobserver variability in the classification of MPCM in two groups of observers: mastocytosis experts and general dermatologists. MATERIALS AND METHODS: Nineteen cases of childhood MPCM were shown blindly, for classification as monomorphic or polymorphic type, to 10 independent observers (eight dermatologists, one allergist and one haematologist) from Europe and North America with a vast experience in the management of paediatric mastocytosis. Also, the same cases were shown on a screen to 129 general dermatologists attending a meeting; their votes were registered by remote controls. The interobserver variability kappa coefficient (with 95% confidence interval) was calculated to measure the reliability of the correlation. RESULTS: The value of kappa interobserver variability coefficient for the group of 10 experts (95% confidence interval) was 0.39 (0.18-0.63), which is considered as 'fair'. The value of kappa interobserver variability coefficient for the group of 129 general dermatologists (95% confidence interval) was 0.17 (0.06-0.39), which is considered as 'slight'. A complete agreement of all 10 experts was achieved in only four of 19 cases (21.1%) The most voted choice was concordant between the two groups in only 11 of the 19 cases. CONCLUSIONS: We failed to validate the classification system of childhood MPCM in monomorphic and polymorphic types. While the rate of agreement was low for mastocytosis experts, it was nearly the agreement expected by chance in general dermatologists.

Capillary malformation-arteriovenous malformation syndrome: a multicentre study.

BACKGROUND: Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a rare syndrome with characteristic skin lesions that are associated with fast-flow vascular malformations (FFVMs) in one-third of patients. Few case series have been described, and none in Spain. AIM: To identify the prevalence of dermatological parameters, FFVMs and associated features in a large series of patients with CM-AVM. METHODS: We conducted an observational study of patients with CM-AVM syndrome diagnosed in 15 Spanish hospitals over 3 years. The main clinical, radiological, genetic findings and associated diseases were analysed. RESULTS: In total, 64 patients were assessed. In 26.5% of cases, the diagnosis was incidental. In 75% of patients, there was one significantly larger macule, which we termed the 'herald patch'. FFVMs were detected in 34% of the patients, with 30% located on the skin, 7.8% in the brain and in 1.5% in the spine. There was a positive family history in 65% of the 64 patients. Genetic analysis was performed for RASA1 mutations in 57 patients, of whom 42 (73%) had a positive result. All 4 patients tested for EPHB4 mutations had a positive result. No tumour lesions were detected in the series, except for five infantile haemangiomas. CONCLUSIONS: Our data on clinical lesions, associated FFVM, family history and genetics are similar to those previously published in the literature. An extensive data analysis failed to demonstrate any statistically significant association between the presence of an FFVM and any clinical, familial or genetic parameter that could predict its onset, although a link between the presence of a herald patch on the midline face and the presence of a brain FFVM was observed. We did not detect any genotype-phenotype correlation.

Histopathological hallmarks of cutaneous lesions of capillary malformation-arteriovenous malformation syndrome.

IMPORTANCE: Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a recently described syndrome with distinctive cutaneous lesions. Very little is known about the histopathology of these lesions. OBJECTIVE: The purpose of the study was to evaluate the histopathological characteristics of the pink macules of the CM-AVM syndrome and to investigate if these pink macules could be classified as capillary malformations or arteriovenous malformations based on their histopathological features. DESIGN-SETTINGS-PARTICIPANTS: We conducted a retrospective multicenter study involving eight hospitals in Spain. Fifteen biopsies from pink macules of the CM-AVM syndrome were analysed and compared with five biopsies of diverse capillary malformations and three stage I arteriovenous malformations. RESULTS: Pink macules' biopsies of the CM-AVM syndrome showed similar features including a high vascular density encompassing capillaries and numerous thick-walled arterioles mainly located in the superficial dermis, a predominance of elongated over round vessels, scarce or absent erythrocytes within the lumina and discrete perivascular inflammation. CMs were characterized by an increased number of capillary-type vessels mostly rounded and located in the upper dermis. AVMs were composed by highly increased numbers of vessels with a branching pattern involving the full thickness of the dermis, without erythrocytes within the lumina. Wilms tumour 1 protein was positive in the endothelial cells both in pink macules of the CM-AVM and in arteriovenous malformations. CONCLUSIONS AND RELEVANCE: Pink macules of the CM-AVM syndrome seem to be different from capillary malformations. Our results suggest that histologically and immunohistochemically they are closer to incipient arteriovenous malformations than to capillary malformations. A deepened knowledge about the nature of these skin lesions will contribute to the better understanding of capillary malformation-arteriovenous malformation syndrome, and will open the possibility of new and more specific treatments in the future.

Update on Mastocytosis (Part 1): Pathophysiology, Clinical Features, and Diagnosis.

Mastocytosis is a term used to describe a heterogeneous group of disorders characterized by clonal proliferation of mast cells in various organs. The organ most often affected is the skin. Mastocytosis is a relatively rare disorder that affects both sexes equally. It can occur at any age, although it tends to appear in the first decade of life, or later, between the second and fifth decades. Our understanding of the pathophysiology of mastocytosis has improved greatly in recent years, with the discovery that somatic c-kit mutations and aberrant immunophenotypic features have an important role. The clinical manifestations of mastocytosis are diverse, and skin lesions are the key to diagnosis in most patients.

Update on Mastocytosis (Part 2): Categories, Prognosis, and Treatment.

Mastocytosis is a term used to describe a heterogeneous group of disorders characterized by clonal proliferation of mast cells in different organs. The organ most often affected is the skin. The World Health Organization classifies cutaneous mastocytosis into mastocytoma, maculopapular cutaneous mastocytosis, and diffuse mastocytosis. The systemic variants in this classification are as follows: indolent systemic mastocytosis (SM), aggressive SM, SM with an associated clonal hematological non-mast cell lineage disease, mast cell leukemia, mast cell sarcoma, and extracutaneous mastocytoma. The two latest systemic variants are rare. Although the course of disease is unpredictable in children, lesions generally resolve by early adulthood. In adults, however, the disease tends to persist. The goal of treatment should be to control clinical manifestations caused by the release of mast cell mediators and, in more aggressive forms of the disease, to reduce mast cell burden.

CD133 expression in normal skin and in epithelial cutaneous tumors.

BACKGROUND: Expression of human CD133 (human prominin-1) in cancer cells has been postulated to be a marker of stemness and is considered as a putative marker of cancer stem cells (CSCs). We designed a study to describe the expression pattern of CD133 in normal skin and in epithelial cutaneous neoplasms. METHODS: The CD133 immunohistochemical expression of forty-three eccrine and apocrine tumors was compared to that observed in other epithelial tumors of the skin. In addition, flow cytometry was used to detect the CD133 expression of four epithelial skin neoplasms, including one porocarcinoma. RESULTS: CD133 immunoreactivity at the apical or at the apicolateral surface of cells forming glandular structures was observed. Cells from solid areas of benign or malignant tumors were not stained. The porocarcinoma derived culture cells showed a 22% of CD133 positive cells using flow cytometry, while squamous cell carcinoma cultures contained less than 0.1%. CONCLUSIONS: These observations indicate that CD133 is a specific marker of glandular differentiation that could be included in the diagnostic panel of cutaneous tumors with possible eccrine or apocrine differentiation. However, the use of CD133 expression as a marker of CSCs should be interpreted with caution in experiments of skin.

[Homogeneous clinical behavior of a group of cutaneous B-cell lymphomas]. / Comportamiento clínico homogéneo de un grupo de linfomas cutáneos de células B.

PURPOSE: To assess the non-cutaneous involvement in primary B-cell non-Hodgkin's lymphoma (NHL) of the skin. PATIENTS AND METHODS: Data from 45 patients with B-cell NHL of the skin were retrospectively analysed. The patients were diagnosed on histologic and immunocytochemical grounds between June 1977 and July 1993, and 14 cases were selected for their exclusively cutaneous initial involvement. Initial treatment, response to therapy, disease-free survival characteristics of relapse and therapeutic sequence were evaluated in every case. RESULTS: Cutaneous involvement presented as nodules or patches, on a single location, in 12 cases, or disseminated, in 2 others. No prognostic factor could be identified, and complete remission was attained in all cases. Cutaneous relapse was seen in 7 patients after 4 to 108 months since diagnosis. Extracutaneous dissemination was not seen in any case, and 13 patients are alive and disease-free. A 90 year-old woman died of toxic complications. CONCLUSIONS: The clinical facts reported here confirm the not too aggressive behaviour of certain B-cell cutaneous NHL, probably related with their origin on the skin itself.

Plasma levels of 8-methoxypsoralen after bath-PUVA for psoriasis: relationship to disease severity.

Plasma levels of 8-methoxypsoralen (8-MOP) were determined by high-pressure liquid chromatography in 19 patients with psoriasis who were receiving bath-PUVA treatment, at different time points after the psoralen bath. The levels of 8-MOP varied between < 5 ng/ml (lower limit of detection) and 34 ng/ml, and we found a relationship between the plasma psoralen levels and the severity of the disease.

Infrequent expression of protein p53 in epidermotropic variants of cutaneous T-cell lymphoma.

Although diverse types of lymphomas have been examined for immunohistochemical detection of p53 protein, little information is available with regard to p53 protein expression in CTCL. We analyzed cutaneous biopsy specimens of 22 patients with the diagnoses of mycosis fungoides or Sézary syndrome with polyclonal rabbit anti-p53 antiserum CM-1. Staining of neoplastic cells was observed only in two patients with advanced disease. Overexpression of p53 protein does not seem to be a major feature of either mycosis fungoides or Sézary syndrome.

CO2, argon, and pulsed dye laser treatment of angiofibromas.

BACKGROUND: Tuberous sclerosis is a complex disorder of hamartoma formation in many organs, particularly the skin, brain, eye, kidney, and heart. The characteristic skin lesions are angiofibromas (AF), the shagreen patch, periungual fibromas, and "ash-leaf" white macules. Treatment for AF has previously included electrocoagulation, electrodesiccation and curettage, dermabrasion, excision, cryosurgery, and oral 13-cis retinoic acid. Both argon and CO2 lasers have been used in isolated cases to treat AF. OBJECTIVE: The purpose of this work is the study of the application of three different lasers in the treatment of facial AF. METHODS: Ten patients with facial AF were treated with CO2, argon, and pulsed dye lasers. Patients' AF were graded with regard to the size and color of the lesions. A 2-3-cm2 test was assayed on the face of all patients with each laser before performing a complete treatment and in order to choose the best laser. RESULTS: Results were considered excellent in seven patients and good in three patients, with decrease of erythema and flattening of the AF. Minimal scarring was noted in two patients. Transient erythema was observed in patients treated with the CO2 laser. All patients or their parents considered the treatment cosmetically satisfactory. CONCLUSION: We found the CO2 laser to be a better therapeutic tool than the argon laser to treat AF, especially in those patients with multiple and protuberant AF. The argon laser would be more useful in those patients with very red AF and light complexion, and the pulsed dye laser in those with very red and flat AF.

Urticaria pigmentosa: a review of 67 pediatric cases.

Mastocytosis is a disorder of mast cell proliferation that may appear during infancy, childhood, or adulthood. We studied 67 consecutive patients (33 males, 34 females) with urticaria pigmentosa and assessed them fully to determine the presence of systemic involvement. Ages at onset of lesions ranged from birth to 11 years, with most developing in the first year of life. Pruritus was the primary symptom. Hematologic and serum chemistry profile, radiologic skeletal surveys, and bone marrow aspirations were performed. Slight anemia was present in three patients. Radiologic bone lesions were observed in eight. Bone marrow aspirates showed slight changes in six patients, with only an increased number of mast cells in an additional patient. The disease tended to resolve spontaneously. This prospective study emphasizes the benign nature of pediatric urticaria pigmentosa.

Cutaneous metastases from prostatic cancer.

The skin is involved in metastases from 2-9% of malignant tumors. These usually tend to spread to the skin relatively late in the course of the disease. Skin metastases of prostatic origin are quite uncommon and preferentially localized to the lower abdomen and genital area. We present a case of cutaneous metastasis from prostatic adenocarcinoma that preceded diagnosis of the primary tumor and was located on the neck.