Primary cutaneous follicular helper T-cell lymphoma: diagnostic pitfalls of this new lymphoma subtype.

The recently proposed entity of cutaneous follicular helper T (T(FH)) cell lymphoma (CT(FH)CL) harbors distinct clinical and histopathologic features. Here, diagnostic pitfalls are exemplified in a case report and by review of the literature. A 45-year-old patient developed rapidly growing nodules and plaques on upper arms and buttocks, which were initially misdiagnosed as primary cutaneous follicle center B-cell lymphoma (CFCL). Consequently, systemic therapy with rituximab failed and consecutive skin biopsies revealed CT(FH)CL (CD3+CD4+CD10+PD-1+bcl6+ICOS+CXCL13+). Interestingly, the prima vista PD-1-positive and CD10-positive tumor cells lost PD-1 expression in follow-up biopsies while retaining CD10, ICOS and CXCL13 expression. All biopsy specimens displayed an identical clonal T-cell population. Initially, nodules were controlled by local radiotherapy and oral psoralen combined with ultraviolet A (PUVA) therapy. However, disease recurred and progressed rapidly with disseminated nodules. Treatment with bexarotene, methotrexate and polychemotherapy failed to stop disease progression. Finally, modified total skin electron beam radiation resulted in complete remission. Disease stabilized on maintenance therapy with bexarotene in combination with ultraviolet A (UVA) therapy. The case highlights that because of concomitant B-cell stimulation, CT(FH)CL clinicopathologically is prone to be mistaken for CFCL. Importantly, CT(FH)CL might lose PD-1 while retaining CD10 expression in later stages, which may lead to confusion in distinguishing CT(FH)CL from CFCL.

Do-it-yourself cement work: the main cause of severe irritant contact dermatitis requiring hospitalization.

BACKGROUND: There are myriads of potentially irritant agents causing acute irritant contact dermatitis. In the large majority of cases, dermatitis is mild to moderate, and patients do not need hospitalization. However, some agents or special circumstances may cause severe dermatitis requiring more intensive therapy. OBJECTIVES: The aim of this study was to evaluate causative agents of severe acute irritant contact dermatitis requiring hospitalization. METHODS: In this single-centre observational cohort study, we included 54 consecutive patients presenting with signs and symptoms of acute irritant contact dermatitis for which hospitalization was necessary. The severity of dermatitis was graded (grade I-IV) according to intensity, and details related to the skin irritation (irritant agent, area of exposure, time interval to onset of symptoms, and duration of hospitalization) were determined. RESULTS: All cases with severe ulcerative dermatitis (grade IV) were caused by wet cement, owing to prolonged skin contact. These cement burns are clearly associated with amateur work, younger age, male preponderance, and leg localization. CONCLUSIONS: The study data provide clear-cut evidence that wet cement is a severely irritant substance that regularly causes the most severe form of acute irritant contact dermatitis. The main causative prerequisite for these cement burns is do-it-yourself work with poor protective measures.

Survivin-specific T-cell reactivity correlates with tumor response and patient survival: a phase-II peptide vaccination trial in metastatic melanoma.

BACKGROUND: Therapeutic vaccination directed to induce an anti-tumoral T-cell response is a field of extensive investigation in the treatment of melanoma. However, many vaccination trials in melanoma failed to demonstrate a correlation between the vaccine-specific immune response and therapy outcome. This has been mainly attributed to immune escape by antigen loss, rendering us in the need of new vaccination targets. PATIENTS AND METHODS: This phase-II trial investigated a peptide vaccination against survivin, an oncogenic inhibitor-of-apoptosis protein crucial for the survival of tumor cells, in HLA-A1/-A2/-B35-positive patients with treatment-refractory stage-IV metastatic melanoma. The study endpoints were survivin-specific T-cell reactivity (SSTR), safety, response, and survival (OS). RESULTS: Sixty-one patients (ITT) received vaccination therapy using three different regimens. 55 patients (PP) were evaluable for response and survival, and 41/55 for SSTR. Patients achieving progression arrest (CR + PR + SD) more often showed SSTRs than patients with disease progression (p = 0.0008). Patients presenting SSTRs revealed a prolonged OS (median 19.6 vs. 8.6 months; p = 0.0077); multivariate analysis demonstrated SSTR as an independent predictor of survival (p = 0.013). The induction of SSTRs was associated with gender (female vs. male; p = 0.014) and disease stage (M1a/b vs. M1c; p = 0.010), but not with patient age, HLA type, performance status, or vaccination regimen. CONCLUSION: Survivin-specific T-cell reactivities strongly correlate with tumor response and patient survival, indicating that vaccination with survivin-derived peptides is a promising treatment strategy in melanoma.

An intact retinoblastoma protein-binding site in Merkel cell polyomavirus large T antigen is required for promoting growth of Merkel cell carcinoma cells.

Merkel cell carcinoma (MCC) is a highly aggressive skin cancer that frequently harbours Merkel cell polyomavirus (MCV) DNA integrated in the genome of the tumor cells. In our study, we elaborate our recent finding that MCV-positive MCC cell lines require the expression of the viral T antigens (TA). Indeed, in a xeno-transplantation model, we prove that TA expression is essential also in an in vivo situation, as knock down of TA leads to tumor regression. Moreover, rescuing TA short hairpin RNA (shRNA)-treated MCV-positive MCC cells by ectopic expression of shRNA-insensitive TAs clearly demonstrates that the observed effect is caused by TA knockdown. Notably, introduction of a mutation in the LTA protein interfering with LTA binding to the retinoblastoma protein (RB) ablated this rescue. The importance of this interaction was further confirmed as LTA-specific knockdown leads to explicit cell growth inhibition. In summary, the presented data demonstrate that established MCV-positive MCC tumors critically depend on TA expression, in particular the LTA and RB interaction, for sustained tumor growth. Consequently, interference with LTA/RB interaction appears as promising strategy to treat MCC.

Hazard rates for recurrent and secondary cutaneous melanoma: an analysis of 33,384 patients in the German Central Malignant Melanoma Registry.

BACKGROUND: Knowledge about the risk for recurrence and secondary cutaneous melanoma (CM) is an important basis for patient counseling and planning of follow-up examinations. OBJECTIVES: This study aimed to analyze stage- and time-dependent hazard rates (HR) and discusses current surveillance recommendations. METHODS: Follow-up data of 33,384 patients with incident CM in stages I to III (American Joint Committee on Cancer 2002) were recorded by the German Central Malignant Melanoma Registry in 1976 through 2007. Survival was based on Kaplan-Meier estimates and HRs were calculated. RESULTS: Recurrences were recorded in 4999 patients (stage I, 7.1%; stage II, 32.8%; and stage III, 51.0%). Ten-year recurrence-free survival was 78.9% (95% confidence interval 73.1-90.5); in stage I, 89.0%; stage II, 56.9%; and stage III, 36.0%. Whereas HR for recurrent CM showed a constantly low level less than or equal to 1:125 per year for stage IA, clearly higher HRs of greater than or equal to 1:40 were recorded in stage IB for the first 3 years and generally in stages II to III. Of all patients 2.3% developed secondary melanomas, with a consistently low HR of less than 1:220 per year. LIMITATIONS: As German recommendations discontinued regular follow-up examinations after 10 years, no information can be given beyond this time point. Follow-up data of longer than 5 years were available in 41.4% of patients. CONCLUSION: For patients at stage IA with thin melanoma and low HR for recurrent CM the need for surveillance remains questionable. For patients with higher HR greater than 1:40 per year, intensified surveillance strategies should be taken into account.

Diagnosis of drug hypersensitivity in children and adolescents: discrepancy between physician-based assessment and results of testing.

BACKGROUND: Diagnosis of drug hypersensitivity is often based on history alone. But such a vague diagnosis may cause limitations of therapeutic options in the future. To confirm or rule out drug hypersensitivity, skin testing, in vitro studies, and challenge tests are necessary. However, the diagnostic value of this complex and time-consuming allergologic work-up, especially in children, remains controversial. OBJECTIVE: Aim of this retrospective analysis was to compare the results of diagnostic testing in children and adolescents with drug hypersensitivity diagnosed on clinical grounds, i.e., temporal relationship and observation of symptoms alone. METHODS: We studied 43 children and adolescents (23 females, 20 males, mean age 13) with a history of immediate or delayed hypersensitivity symptoms in temporal relation to drug treatment using standardized skin testing followed by oral challenges. Patients with suspected penicillin hypersensitivity were further evaluated with in vitro tests. RESULTS: Drug hypersensitivity was excluded in 40 patients by tolerated oral challenge tests with the incriminated drug. In two patients, positive challenge tests confirmed non-steroidal anti-inflammatory drug hypersensitivity. One patient with amoxicillin-associated exanthema developed positive late skin test reactions to aminopenicillins. CONCLUSION: In childhood and adolescence, allergologic testing in cases of suspected drug hypersensitivity is of importance both to establish a correct diagnosis and to prevent unjustified withholding of a drug or class of drugs.

Suspicion of macrolide allergy after treatment of infectious diseases including Helicobacter pylori: results of allergological testing.

BACKGROUND: Macrolides are useful in a wide range of bacterial infections including upper and lower respiratory tract, skin, and sexually transmitted diseases and are used in Helicobacter pylori eradication regimen. Skin symptoms occurring during drug therapy are mostly attributed to the antibiotic, causing considerable limitations of future therapeutic options. The aim of this retrospective analysis was to demonstrate results of diagnostic testing in cases of clinically suspected immediate and delayed macrolide hypersensitivity. METHODS: A total of 125 patients with a history of immediate or delayed hypersensitivity symptoms in temporal relation to treatment with a macrolide antibiotic were studied using standardised skin tests followed by oral challenges. Selected patients with severe symptoms were further evaluated with in vitro tests. RESULTS: Macrolide hypersensitivity was excluded in 109 patients (87.2%) by tolerated oral challenge tests. During 113 challenges in four patients an exanthema was provoked by the suspected macrolide. Only one patient developed a positive late skin test reaction. Out of the 28 Helicobacter pylori-treated patients, one patient with clarithromycin allergy was identified, whereas in eight cases amoxicillin allergy caused the exanthema. Laboratory tests using the suspected macrolides were constantly negative. CONCLUSIONS: History alone leads to an over-estimation of macrolide hypersensitivity. Moreover, skin and in vitro tests seem to be not very useful in identifying hypersensitive patients. Challenge tests appear to be necessary for definitely confirming or ruling out macrolide allergy.

Wasp venom immunotherapy induces activation and homing of CD4(+)CD25(+) forkhead box protein 3-positive regulatory T cells controlling T(H)1 responses.

BACKGROUND: Despite a growing interest in CD4(+)CD25(+) forkhead box protein 3 (Foxp3)-positive regulatory T (Treg) cells, the fundamental parameters of the activation and homing of these cells during wasp venom immunotherapy (VIT) are largely unknown. OBJECTIVE: We investigated longitudinally the phenotype and function of Treg cells in a well-characterized homogeneous group of patients with wasp venom allergy during VIT. METHODS: In 30 patients peripheral Treg cells were ex vivo monitored for their activation status and homing capacities by means of flow cytometric analysis before and after 1 and 6 months of VIT. In addition, the in vitro suppressive activity of Treg cells, as well as cytokine secretion, in response to wasp venom was analyzed. RESULTS: One month after initiating VIT, the proportion of both CD4(+)CD25(+)Foxp3(+) and CD4(+)Foxp3(+) Treg cells significantly decreased in peripheral blood. Coexpression of the lymph node homing receptors CCR7/CD62L were induced in CD4(+)Foxp3(+)CD45RO(+) Treg cells, indicating recirculation of VIT-activated Treg cells in secondary lymphoid organs. In vivo imaging by means of color duplex ultrasonography of the axillary draining lymph nodes demonstrated a VIT-induced 4-fold augmentation in afferent arterial blood flow. Furthermore, increased activation markers (CD45RO and HLA-DR) of Treg cells correlated with effective in vitro suppression of wasp venom-driven T-cell proliferation. After 1 month of VIT, Treg cell depletion in vitro greatly enhanced wasp venom-induced IFN-γ secretion. CONCLUSIONS: Allergen exposure during VIT simultaneously induces the activation and selective homing of circulating Treg cells. Functionally, on the one hand, Treg cells balance the immune reaction toward tolerance, and on the other hand, they are involved in controlling overwhelming T(H)1 responses.

Blood vessel density in Basal cell carcinomas and benign trichogenic tumors as a marker for differential diagnosis in dermatopathology.

In order to get insight into the density of blood vessels in the stroma of benign and malignant trichogenic neoplasms, immunohistological quantification of CD 31 positive vessels was performed in 112 tumors, comprised of 50 BCCs of nodular (35) or morphoeic (15) growth patterns, 17 Pinkus' tumors, as well as 17 trichoepitheliomas of which 6 were desmoplastic, 8 trichofolliculomas, and 20 trichoblastomas. Methods. Vessel density was counted within the tumors, in the tumor-surrounding stroma, and, as a control, in the normal skin of the operation specimen. The results were compared using statistical methods. Results. Whereas, irrespective of the patients' age and location of tumors, the vessel density in normal skin showed no significant differences (8.8 ± 2.7), the counts in the peritumoral stroma revealed significant differences between the different tumors investigated. The highest counts were obtained in BCC (24.7 ± 6.7) and the lowest in benign trichogenic neoplasms (around 14) Pinkus' tumors revealed intermediate counts (19.7 ± 6.6). The vessel densities within the tumors were generally low, and no correlation to the dignity was found. Conclusion. Determination of blood vessel density in the peritumoral stroma may be an additional parameter for differential diagnosis of trichogenic tumors of uncertain dignity.

Pigmentation, Melanocyte Colonization, and p53 Status in Basal Cell Carcinoma.

Basal cell carcinoma (BCC) is the most common neoplasm in the Caucasian population. Only a fraction of BCC exhibits pigmentation. Lack of melanocyte colonization has been suggested to be due to p53-inactivating mutations in the BCC cells interfering with the p53-proopiomelanocortin pathway and the production of alpha melanocyte-stimulating hormone in the tumor. To evaluate this, we determined tumor pigmentation as well as expression of melan-A and of p53 in 49 BCC tissues by means of immunohistochemistry. As expected, we observed a positive relation between tumor pigmentation and melan-A positive intra-tumoral melanocytes. Melanocyte colonization and, to a lesser extent, p53 overexpression showed intraindividual heterogeneity in larger tumors. p53 overexpression, which is indicative of p53 mutations, was not correlated to melanocyte colonization of BCC. Sequencing of exon 5-8 of the p53 gene in selected BCC cases revealed that colonization by melanocytes and BCC pigmentation is neither ablated by p53 mutations nor generally present in BCCs with wild-type p53.

A dynamic immunological synapse mediates homeostatic TCR-dependent and -independent signaling.

For homeostasis, T cells integrate non-cognate TCR-dependent and -independent signals to survive and weakly proliferate. In contrast to antigen-specific, stable, and long-lived contacts, signaling in short-lived homeostatic interactions depends upon the coordination of ongoing T-cell migration on the surface of DC and signaling at the cell-cell junction. To mimic peripheral tissues and analyze how T-cell migration and cell-cell signaling are integrated, we used live-cell imaging and 3-D reconstruction of fixed conjugates between DO11.10 T cells and DC in 3-D low-density collagen matrices. T cells simultaneously maintained amoeboid migration and polarized towards the DC, leading to a fully dynamic interaction plane that delivered signals for homeostatic T-cell survival and proliferation. The contact plane comprised three zones, the actin-rich leading edge poor in signal but driving migration, a mid-zone mediating TCR/MHC-induced signal associated with proliferation, and the rear uropod mediating predominantly MHC-independent signals. Thus a dynamic immunological synapse with distinct signaling sectors enables moving T cells to serially sample resident tissue cells and acquire molecular information "en passant".