Granulomatous dermatitis in the context of chronic myelomonocytic leukemia: More than just reactive infiltrates. An illustrative case report with literature review.

Traditionally, skin involvement in chronic myelomonocytic leukemia (CMML) has been considered to be either specific (leukemia cutis) or non-specific, with granulomatous dermatitis included in the latter group. More recently, the true nature of the myeloid cells present in the cutaneous infiltrates of this theoretically reactive dermatitis is being clarified with the use of new molecular techniques such as next-generation sequencing. The same mutations in bone marrow (BM) myeloid neoplastic cells and in the cells of cutaneous infiltrates have been found. We present the case of a 77-year-old man who presented with spread and treatment-resistant skin granulomatous lesions previous to the diagnosis of CMML. The same clonal mutations in SRSF2, IDH1, and RUNX1 were found in both skin and BM with resolution of the lesions after the initiation of azacytidine. In conclusion, we report an exceptional case in which specific granulomatous cutaneous lesions have preceded and allowed the earlier diagnosis of an underlying CMML and a review of all previous similar cases in the literature, including molecular alterations.

Gorlin-Like Phenotype in a Young Girl With a De Novo PTCH2 Variant Mutation of Uncertain Significance.

ABSTRACT: Gorlin syndrome, also known as basal cell nevus syndrome, is an autosomal dominant genetic disorder that predisposes humans to tumors. In most cases, this syndrome results from inactivating mutations in the patched homologue 1 gene. Basal cell carcinomas are one of the main characteristics of this syndrome and serve as a major diagnostic criterion. Gorlin syndrome shows a variable phenotype, and recently, other less common mutations in the suppressor of fused homologue or patched homologue 2 genes have been documented in individuals with this syndrome. We present the case of a patient with early-onset basal cell carcinomas and a mild Gorlin syndrome phenotype, attributed to a de novo patched homologue 2 variant of uncertain significance, which has not been previously reported in the literature.

Hydroa Vacciniforme Lymphoproliferative Disorder in a Young Spanish Woman: An Infrequent Case With Fatal Outcome.

ABSTRACT: Hydroa vacciniforme (HV) lymphoproliferative disorder is a rare NK/T-cell lymphoma mainly affecting children and with a clinical resemblance to HV, which is mostly reported in Latin American and some Asian countries. Overall, the mature T cell and NK-cell neoplasms are now grouped into 9 families based on diverse concepts: cell of origin/differentiation state, clinical scenario, disease localization, and cytomorphology. HV lymphoproliferative disorder is listed within the group of Ebstein Barr Virus-positive T-cell and NK-cell lymphoid proliferations and lymphomas of childhood according to the fifth edition of the World Health Organization Classification of mature lymphoid neoplasms. We report the extraordinary case of a 22-year-old white woman, native of Spain, first presented in 2016 when she started suffering from recurrent facial edema. Four years later, the disease progressed with lymph node spreading and a fatal outcome. Here, we describe the clinical and histological presentation of the lymphoma throughout its evolution. Cases like this can be difficult to classify posing a real challenge to clinicians and pathologists. So, it is vital to be aware of the rare presentation of this disease to be able to identify the clinical and histological picture to make a correct diagnosis and establish an early treatment.

Essential thrombocythemia manifesting as livedoid and purpuric skin lesions: Report of two cases and literature review.

Essential thrombocythemia is a chronic myeloproliferative syndrome which usually runs its course as an asymptomatic elevated platelet count. Cutaneous manifestations secondary to microcirculation abnormalities are rare but can represent a helpful diagnostic clue in order to prevent major thromboembolic events. We report two cases of heterogeneous livedoid and "net-like" skin lesions in the context of essential thrombocythemia with identical histopathologic findings (medium-sized blood vessels with luminal obliteration by eosinophilic material, mostly positive for the platelet marker CD61, without vasculitis). In conclusion, we seek to raise awareness of the clinicopathological features of essential thrombocythemia to allow for prompt diagnosis and treatment.

Concurrent Presentation of Mycosis Fungoides and Primary Cutaneous Marginal Zone LPD: Clinicopathological Study of 4 Cases and Literature Review.

BACKGROUND: Mycosis fungoides is rarely associated to B-cell malignancies, and the few reported cases are mainly internal lymphomas involving secondarily the skin (ie, chronic lymphocytic leukemia). OBJECTIVES: The aim of our study is to describe the clinical and histopathological features of 4 patients presenting with 2 concurrent primary cutaneous lymphomas and review the pertinent literature. METHODS: We identified 4 cases of concurrent primary cutaneous lymphomas in our institutions. An extracutaneous lymphoma was ruled out on the basis of a complete work out. We performed a PubMed search to identify reported cases of primary cutaneous composite or concurrent lymphomas. RESULTS: Eleven cases of primary cutaneous concurrent lymphomas have been described in the literature. Counting all together (our cases and the cases previously described in the literature), mycosis fungoides was the most frequent primary cutaneous T-cell lymphoma (TCL) (13/15), followed by 1 case of peripheral TCL-NOS and 1 case of subcutaneous panniculitis-like TCL. Regarding the associated primary cutaneous B-cell lymphomas, 8/15 cases consisted of low-grade B-cell lymphomas [that is, 5 marginal zone lymphoma (in the most recent classification reclassified as marginal zone lymphoproliferative disorder, MZLD, 2 follicular-center B-cell lymphoma (primary cutaneous follicle-center lymphoma) and 1 low-grade NOS B-cell lymphoma]; 4/15 were associated to Epstein-Barr virus; 1 case consisted of a methotrexate-associated lymphoproliferative disease, and 2 cases consisted of primary cutaneous diffuse large B-cell lymphoma-leg type. CONCLUSIONS: Primary cutaneous concurrent lymphomas are exceptional. Clinicopathological correlation and a complete workout to reach the correct diagnosis may guide the appropriate treatment in each case.

Brentuximab vedotin in the treatment of cutaneous T-cell lymphomas: Data from the Spanish Primary Cutaneous Lymphoma Registry.

BACKGROUND: Brentuximab vedotin (BV) has been approved for CD30-expressing cutaneous T-cell lymphoma (CTCL) after at least one previous systemic treatment. However, real clinical practice is still limited. OBJECTIVES: To evaluate the response and tolerance of BV in a cohort of patients with CTCL. METHODS: We analysed CTCL patients treated with BV from the Spanish Primary Cutaneous Lymphoma Registry (RELCP). RESULTS: Sixty-seven patients were included. There were 26 females and the mean age at diagnosis was 59 years. Forty-eight were mycosis fungoides (MF), 7 Sézary syndrome (SS) and 12 CD30+ lymphoproliferative disorders (CD30 LPD). Mean follow-up was 18 months. Thirty patients (45%) showed at least 10% of CD30+ cells among the total lymphocytic infiltrate. The median number of BV infusions received was 7. The overall response rate (ORR) was 67% (63% in MF, 71% in SS and 84% in CD30 LPD). Ten of 14 patients with folliculotropic MF (FMF) achieved complete or partial response (ORR 71%). The median time to response was 2.8 months. During follow-up, 36 cases (54%) experienced cutaneous relapse or progression. The median progression free survival (PFS) was 10.3 months. The most frequent adverse event was peripheral neuropathy (PN) (57%), in most patients (85%), grades 1 or 2. CONCLUSIONS: These results confirm the efficacy and safety of BV in patients with advanced-stage MF, and CD30 LPD. In addition, patients with FMF and SS also showed a favourable response. Our data suggest that BV retreatment is effective in a proportion of cases.

Granulomatous Dermatitis Heralding Myelodisplastic/Myeloproliferative Neoplasms. Neoplastic or Reactive Cells? A Study of 2 Cases.

ABSTRACT: Skin manifestations in the context of underlying hematological malignancies are well known and not an infrequent clinical finding. They can represent specific neoplastic infiltrates or be considered as reactive. In the latter group, where granulomatous dermatitis is included, controversy has emerged recently. According to newly reported data, the histiocytes comprising these granulomata can carry the same molecular alterations found in the primary process. Moreover, the skin manifestations in these patients are sometimes the initial clue for the diagnosis of the underlying malignancy. We present here 2 cases with granulomatous skin infiltrates preceding the diagnosis of myelodysplastic/myeloproliferative neoplasms. In one of them, the same IDH2 mutation was detected in granulomatous lesions on the skin and in the bone marrow. This was performed by pyrosequencing instead of next-generation sequencing, with improved cost-effectiveness.

Atypical BCL6/GATA3+ Primary Cutaneous Acral CD8-Positive T-Cell Lymphoma: A Diagnostic Challenge.

ABSTRACT: Primary cutaneous acral CD8-positive T-cell lymphoma consists of slow-growing nodules in acral sites with a histopathology, suggesting high-grade lymphoma despite the indolent clinical course. It has been recently included in WHO-EORTC classification for primary cutaneous lymphomas as a provisional entity. A correct diagnosis of this entity is important because its differential diagnosis include more aggressive cutaneous lymphomas. We present a 53-year-old woman with an indolent solitary nodule on her right leg, which histopathologically showed features of CD8-positive T-cell lymphoma, although with some peculiarities, including epidermotropism, absence of CD68 expression, and positivity for GATA3 and Bcl6 in neoplastic cells. This case could contribute to better define the spectrum of this rare cutaneous lymphoma.

Flame Figures in Linear Immunoglobulin A Bullous Dermatosis Secondary to Parvovirus B19 Infection.

ABSTRACT: Flame figures represent a characteristic but nondiagnostic histological finding in eosinophilic dermatoses. Some bullous autoimmune diseases with a predominant eosinophilic infiltrate, such as bullous pemphigoid, pemphigoid gestationis, and pemphigus vegetans, may show them. However, it is rare to find them in predominant neutrophilic bullous dermatoses such as linear immunoglobulin A. We present a 60-year-old man with a history of chronic urticaria, which presented a bullous disease after an acute parvovirus B19 infection. The histological findings showed an exceptional linear immunoglobulin A bullous dermatosis with an eosinophilic infiltrate in the dermis forming "flame figures." The clinical and histopathological findings for this entity may be identical to those of other dermatoses. For this reason, combining these findings with direct immunofluorescence analysis is essential for correct diagnosis of this bullous disease.

Discoid Lupus Erythematosus Presenting With Disfiguring Acneiform Plaques: A Diagnostic Challenge.

ABSTRACT: Hypertrophic and acneiform forms are very rare variants of discoid lupus erythematosus (DLE), which can suppose a diagnostic and therapeutic challenge. We present a South American woman with facial disfiguring lesions of 7 years of evolution with clinical and histopathological characteristic of both hypertrophic and acneiform DLE. No criteria for systemic lupus erythematosus were present in the patient. To the best of our knowledge, no patients with concomitant hypertrophic and acneiform DLE have been previously reported in the literature.

T-Cell-Rich Recurrence of Primary Cutaneous Follicle Center Lymphoma After Systemic Rituximab: A Diagnostic Pitfall.

We report on a 74-year-old man with a cutaneous B-cell follicle center lymphoma, which was treated upfront with systemic rituximab and suffered several local relapses. The first of the local recurrences, 10 months after completion of treatment, was characterized by a dense T-cell infiltrate that obscured a minor population of B-cell lymphoma cells, suggesting a second primary cutaneous T-cell lymphoma. This represents a previously not reported diagnostic pitfall and underscores the importance of performing sequential biopsies when dealing with lymphoma recurrences in this setting.

Inflammatory Cells in Atypical Eruption of Lymphocyte Recovery Carry the Same Mutations as Neoplastic Myeloid Cells.

Cutaneous eruption of lymphocyte recovery (ELR) during bone marrow (BM) aplasia recovery after intensive chemotherapy has been reported in very few patients. The presence of skin rashes in patients with acute leukemia who are undergoing intensive chemotherapy and BM transplantation is a diagnostic challenge because of the clinical similarity between drug eruptions, infiltrates related to the relapse of the underlying disease, cutaneous graft-versus-host disease, and ELR. IDH1 mutations have been identified as a recurrent genetic anomaly in acute myeloid leukemia and myelodysplastic syndromes. However, until now, this IDH1 mutation has not been reported as being shared by myeloid cells and non-neoplastic inflammatory cells in this clinical setting. Here, we present the rare case of a woman diagnosed with myelodysplastic syndrome that evolved into an acute myelogenous leukemia with leukemic cutaneous infiltrate. The patient developed ELR after the intensive chemotherapy administered before BM transplantation. The IDH1 mutation was identified in BM cells and in myeloid and inflammatory cells in skin biopsies before allogeneic BM transplantation. We discuss the main aspects of the differential diagnosis of these cutaneous reactions in leukemic patients and the biological significance of the IDH1 mutation.

[Painful nodules on the soles in a pediatric patient: A diagnostic challenge]. / Nodulos plantares dolorosos tras ejercicio intenso en paciente pediátrica: Un reto diagnóstico.

INTRODUCTION: Idiopathic Palmoplantar Eccrine Hidradenitis (IPPH) is a rare neutrophilic derma tosis, with painful erythematous nodules of sudden onset in the plantar or palmoplantar region, in children without other underlying diseases. OBJECTIVE: To present a case that shows the main clinical and histological characteristics of this entity. CLINICAL CASE: 11-year-old girl with a 48-hours history of painful erythematous-violaceous nodules on the right foot plant associated with fever of up to 38.2 °C, with no history of interest except hyperhidrosis and intense exercising on previous days. Given the clinical suspicion of IPPH, a skin biopsy was performed, which showed inflammatory neutrophil infiltration around eccrine sweat glands and neutrophilic abscesses, confirming the diagnosis. Oral NSAIDs and rest were prescribed, with resolution of the lesions in 7 days. CONCLUSIONS: This case demonstrates the most important aspects of this entity, in many cases underdiagnosed, since it can be confused with other pathologies that occur with painful acral nodules, but have different pathogenic and therapeutic implications. To properly identify the IPPH allows preventing an unnecessary alarm, both patients and their parents, as in dermatologists and pediatricians themselves.

CD30-positive primary cutaneous lymphoproliferative disorders: molecular alterations and targeted therapies.

Primary cutaneous CD30-positive T-cell lymphoproliferative disorders are the second most common subgroup of cutaneous T-cell lymphomas. They include two clinically different entities with some overlapping features and borderline cases: lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma. Molecular studies of primary cutaneous anaplastic large cell lymphoma reveal an increasing level of heterogeneity that is associated with histological and immunophenotypic features of the cases and their response to specific therapies. Here, we review the most significant genetic, epigenetic and molecular alterations described to date in primary cutaneous CD30-positive T-cell lymphoproliferative disorders, and their potential as therapeutic targets.

Mycosis Fungoides Associated With Lesions in the Spectrum of Primary Cutaneous CD30+ Lymphoproliferative Disorders: The Same Process or 3 Coexisting Lymphomas?

Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma, primary cutaneous CD30 lymphoproliferative disorders (pc CD30 LPD) being the second most prevalent. There is evidence that MF and pc CD30 LPD may coexist and share T-cell clonality, suggesting a common origin. These findings were supported by a T-cell receptor clonality assessment by the polymerase chain reaction coupled with capillary electrophoresis, although results produced by this method may be ambiguous. We describe an otherwise healthy 46-year-old man who developed, over the course of 5 months, a tumor consisting of primary cutaneous anaplastic large cell lymphoma and, subsequently, several papules of lymphomatoid papulosis (LyP). Both lymphomas appeared on a single patch of MF, which had been present on the patient's right buttock for at least 2 years. T-cell receptor clonality of the 3 types of neoplastic lesions and apparently non-involved skin were assessed by a next-generation sequencing-based method. We found that MF, primary cutaneous anaplastic large cell lymphoma and LyP harbored the same top 2 clones. Non-involved skin harbored other T-cell clones. In this patient, these findings suggest that MF, LyP and pc CD30 LPD were different clinicopathological manifestations arising from the neoplastic proliferation of the same T-cell clone.

Cutaneous hemophagocytosis: Clinicopathologic features of 21 cases.

BACKGROUND: Hemophagocytosis is well known in cytotoxic cutaneous T-cell lymphomas (CTCLs), in which it may represent a sign of hemophagocytic lymphohistiocytosis syndrome (HLHS), and is also typical of cutaneous Rosai-Dorfman disease (cRDD) (without prognostic relevance). Only rarely, has cutaneous hemophagocytosis (CH) been described in other skin conditions. OBJECTIVE: To characterize the clinicopathologic features of CH in skin biopsy specimens from patients with conditions other than CTCL or cRDD. METHODS: Case series analyzing clinicopathologic features and follow-up data on patients presenting with histopathologic signs of CH. RESULTS: Biopsy specimens from 21 patients were included. None of the patients had HLHS. The majority (n = 11) presented with leukocytoclastic vasculitis. Other associated diseases were lupus erythematous (n = 2), arthropod bite reaction (n = 2), erysipelas (n = 1), acne conglobata (n = 1), and Sweet syndrome (n = 1). Three patients had a nonspecific rash concomitant with Chlamydia pneumonia, middle ear infection, and pharyngitis, respectively. LIMITATIONS: This was a single-center, retrospective study. CONCLUSION: Isolated CH in conditions other than CTCL and cRDD is a histopathologic finding related mostly to leukocytoclastic vasculitis. Extensive investigations should be performed only if patients have other signs or symptoms of HLHS.

The Histopathological Spectrum of Pseudolymphomatous Infiltrates in Cutaneous Lupus Erythematosus.

The occurrence of pseudolymphomatous infiltrates in cutaneous lupus erythematosus (cLE) is described mainly in lupus panniculitis and lupus tumidus/lymphocytic infiltration of the skin (Jessner-Kanof). We collected 15 cases of pseudolymphomatous cLE other than lupus panniculitis and lupus tumidus (M:F = 4:11; age range: 23-79 years; mean age: 50.9 years; median age: 57 years). Of the 15 cases, 9 (60%) were characterized by dense nodular infiltrates. Three cases (20%) showed an angiocentric pattern with cytological atypia of lymphoid cells; 2 cases (13.3%) showed a band-like infiltrate mimicking mycosis fungoides, and 1 case had mixed features of the band-like and angiocentric patterns. Clues to the histopathological diagnosis of cLE were presence of interface dermatitis, clusters of plasmacytoid dendritic cells, and dermal mucin deposition. Our study shows that the spectrum of pseudolymphomatous presentations of cLE is broader than previously described, including band-like cases that may be misconstrued as mycosis fungoides, and angiocentric cases that may be misinterpreted as an aggressive lymphoma. Recognition of such cases is possible only on careful clinicopathologic correlation and requires a high level of histopathological suspicion to allow a correct diagnosis and the proper management of the patients.

Genital folliculo-sebaceous cystic hamartoma: A claim of the stroma as a clue in the diagnosis of proliferations with follicular differentiation.

Folliculo-sebaceous hamartomas comprise a series of entities whose boundaries are imprecise. We present the clinical case of a folliculo-sebaceous cystic hamartoma of genital localization where the diagnosis was established based on the epithelial proliferation, but mostly, on the characteristic stroma. Because this lesion lacked of the cystic component, we mention the most frequent differential diagnoses and review the literature of the few cases published on this infrequent localization.

MYD88 L265P mutation in cutaneous involvement by Waldenström macroglobulinemia.

Cutaneous manifestations of Waldenström macroglobulinemia (WM) may occur because of several mechanisms, the least common being direct skin infiltration by neoplastic cells. We report a case of patient that after 4-year history of indolent WM developed skin infiltration by lymphoplasmacytoid cells in the form of a small, mildly indurated plaque on the anterior chest. MYD88 L265P mutation was detected both in the previous bone marrow biopsy and in the cutaneous lesion. We review the impact of this new genetic tool in the diagnosis and treatment of lymphoplasmacytic proliferations.

Nodular Sclerodermatous Chronic Cutaneous Graft-Versus-Host Disease (GvHD): A New Clinicopathological Variant of Cutaneous Sclerodermatous GvHD Resembling Nodular/Keloidal Scleroderma.

Cutaneous chronic graft-versus-host disease (GvHD) has a broad spectrum of clinicopathological presentations, the most common ones being poikiloderma, lichen planus-like eruptions, lichen sclerosus-like lesions, morphea-like plaques, and deep sclerosis. New forms of chronic cutaneous GvHD with different clinicopathological characteristics have been described, most of them mimicking cutaneous manifestations of autoimmune diseases. We report the case of a 35-year-old man who underwent allogenic stem cell transplantation for a therapy-associated acute myeloid leukemia and developed an acute GvHD with involvement of skin and gastrointestinal tract. He subsequently presented with chronic sclerodermatous cutaneous GvHD, followed by the appearance of indurated erythematous papules and plaques located on his back, resembling the nodular/keloidal form of cutaneous scleroderma on both clinical and histopathological grounds. This peculiar clinicopathologic presentation of chronic cutaneous GvHD was never described previously.