Epigenomic Analysis of Sézary Syndrome Defines Patterns of Aberrant DNA Methylation and Identifies Diagnostic Markers.

Sézary syndrome (Sz) is a malignancy of skin-homing CD4(+) memory T cells that is clinically characterized by erythroderma, lymphadenopathy, and blood involvement. Distinction of Sz from erythroderma secondary to inflammatory skin diseases (erythrodermic inflammatory dermatosis [EID]) is often challenging. Recent studies identified recurrent mutations in epigenetic enzymes involved in DNA modification in Sz. Here we defined the DNA methylomes of purified CD4(+) T cells from patients with Sz, EID, and healthy control subjects. Sz showed extensive global DNA methylation alterations, with 7.8% of 473,921 interrogated autosomal CpG sites showing hypomethylation and 3.2% hypermethylation. Promoter CpG islands were markedly enriched for hypermethylation. The 126 genes with recurrent promoter hypermethylation in Sz included multiple candidate tumor suppressors that showed transcriptional repression, implicating aberrant methylation in the pathogenesis of Sz. Validation in an independent sample set showed promoter hypermethylation of CMTM2, C2orf40, G0S2, HSPB6, PROM1, and PAM in 94-100% of Sz samples but not in EID samples. Notably, promoter hypermethylation of a single gene, the chemokine-like factor CMTM2, was sufficient to accurately distinguish Sz from EID in all cases. This study shows that Sz is characterized by widespread yet distinct DNA methylation alterations, which can be used clinically as epigenetic diagnostic markers.

Evaluation of Immunophenotypic and Molecular Biomarkers for Sézary Syndrome Using Standard Operating Procedures: A Multicenter Study of 59 Patients.

Differentiation between Sézary syndrome and erythrodermic inflammatory dermatoses can be challenging, and a number of studies have attempted to identify characteristic immunophenotypic changes and molecular biomarkers in Sézary cells that could be useful as additional diagnostic criteria. In this European multicenter study, the sensitivity and specificity of these immunophenotypic and recently proposed but unconfirmed molecular biomarkers in Sézary syndrome were investigated. Peripheral blood CD4(+) T cells from 59 patients with Sézary syndrome and 19 patients with erythrodermic inflammatory dermatoses were analyzed for cell surface proteins by flow cytometry and for copy number alterations and differential gene expression using custom-made quantitative PCR plates. Experiments were performed in duplicate in two independent centers using standard operating procedures with almost identical results. Sézary cells showed MYC gain (40%) and MNT loss (66%); up-regulation of DNM3 (75%), TWIST1 (69%), EPHA4 (66%), and PLS3 (66%); and down-regulation of STAT4 (91%). Loss of CD26 (≥80% CD4(+) T cells) and/or CD7 (≥40% CD4(+) T cells) and combination of altered expression of STAT4, TWIST1, and DNM3 or PLS3 could distinguish, respectively, 83% and 98% of patients with Sézary syndrome from patients with erythrodermic inflammatory dermatoses with 100% specificity. These additional diagnostic panels will be useful adjuncts in the differential diagnosis of Sézary syndrome versus erythrodermic inflammatory dermatoses.

Score test for association between recurrent events and a terminal event.

The statistical analysis of recurrent events relies on the assumption of independent censoring. When random effects are used, this means, in addition, that the censoring cannot depend on the random effect. Whenever the recurrent event process is terminated by death, this assumption might not be satisfied. Because joint models arising from such situations are more difficult to fit and interpret, clinicians rarely check whether joint modeling is preferred. In this paper, we propose and compare simple, yet efficient methods for testing whether the terminal event and the recurrent events are associated or not. The performance of the proposed methods is evaluated in a simulation study, and the sensitivity to misspecification of the model is assessed. Finally, the methods are illustrated on a data set comprising repeated observations of skin tumors on T-cell lymphoma patients. Copyright © 2016 John Wiley & Sons, Ltd.

Differential expression of TOX by skin-infiltrating T cells in Sézary syndrome and erythrodermic dermatitis.

BACKGROUND: The histopathologic differentiation between Sézary syndrome (SS) and erythrodermic dermatitis may be extremely difficult. In this immunohistochemical study, it was investigated if thymocyte selection-associated high mobility group box protein (TOX) and C-MYC can be used as additional diagnostic markers to differentiate between SS and erythrodermic dermatitis. METHOD: Paraffin-embedded skin biopsies from 15 SS patients and 17 erythrodermic dermatitis patients were stained and scored for TOX or C-MYC expression. RESULTS: Strong nuclear staining for TOX in more than 50% of skin-infiltrating T cells was observed in 13 of 15 (87%) SS cases, whereas erythrodermic dermatitis cases showed weak nuclear staining in 11-50% (median: 25%) of the T cells; strong nuclear staining as found in SS was never observed in erythrodermic dermatitis. No significant differences in C-MYC expression between SS and erythrodermic dermatitis were found. In most patients of both groups, percentages of C-MYC positive-cells varied between less than 10 and 25% of skin-infiltrating T cells. CONCLUSION: Our results suggest that strong expression of TOX in more than 50% of skin-infiltrating T cells in erythrodermic skin is a useful marker in the differentiation between SS and erythrodermic dermatitis, whereas staining for C-MYC does not contribute to differential diagnosis.

Acquired melanocytic nevi in childhood and familial melanoma.

IMPORTANCE: In the surveillance of familial melanoma, the identification of children at greater risk of developing melanoma later in life would serve as a helpful tool. OBJECTIVE: To determine whether acquired melanocytic nevi in childhood are an indicator of risk of melanoma in children from families with familial melanoma. DESIGN, SETTING, AND PARTICIPANTS: A 20-year follow-up study of a cohort of children from families with familial melanoma. Phenotypical data on melanocytic nevi were collected from a random sample of 133 members of families with familial melanoma 2 to 18 years of age with variable risks of being a mutation carrier. More than 20 years of follow-up data (gene-carrier status, diagnosis of melanoma, and excisions of nevi) were collected. In a subgroup of 40 people, childhood phenotypical data were compared with data on nevus numbers in adulthood. Survival analyses, correlation analyses, and t tests were calculated to examine associations. MAIN OUTCOMES AND MEASURES: Nevus count and distribution in childhood were correlated with the occurrence of melanoma and mutation carrier status. RESULTS: Significant risk factors for melanoma were found, specifically in the group with the highest risk of being a mutation carrier: total number of atypical nevi in childhood (hazard ratio [HR], 1.21; 95% CI, 1.02-1.44; P = .03), the nevus count of atypical nevi on the buttocks (HR, 14.00; 95% CI, 2.94-66.55; P = .001), and the number of excisions during follow-up (HR, 1.27; 95% CI, 1.23-1.31; P < .001). The analysis also found a correlation between the distribution of nevi in childhood and adulthood and the distribution of melanomas (correlation, 0.89; 95% CI, 0.67-0.96; and correlation, 0.99; 95% CI, 0.98-1.00; P < .001, respectively for both). CONCLUSIONS AND RELEVANCE: Numbers and distribution of melanocytic nevi in childhood are major indicators of the risk of melanoma in patients from families with familial melanoma.

Surveillance of second-degree relatives from melanoma families with a CDKN2A germline mutation.

BACKGROUND: Lifetime melanoma risk of mutation carriers from families with a germline mutation in the CDKN2A gene is estimated to be 67%. The necessity to include family members in a melanoma surveillance program is widely endorsed, but there is no consensus on which family members should be invited. METHODS: In a retrospective follow-up study, we investigated the yield of surveillance of first- and second-degree relatives of melanoma and pancreatic cancer patients from 21 families with the "p16-Leiden" CDKN2A mutation. Melanoma incidence rates were compared with the general population. RESULTS: Three-hundred and fifty-four first-degree relatives and 391 second-degree relatives were included. Forty-five first-degree relatives and 11 second-degree relatives were diagnosed with melanoma. Most (72%) of second-degree relatives diagnosed with melanoma had become a first-degree relative before diagnosis, due to the occurrence of a melanoma in a parent or sibling. Overall, melanoma incidence rate was 2.1 per 1,000 person years [95% confidence interval (CI), 1.2-3.8] in family members still being second-degree relatives at diagnosis, compared with 9.9 per 1,000 person years (95% CI, 7.4-13.3) in first-degree relatives. The standardized morbidity ratio for melanoma of second-degree relatives compared with the general population was 12.9 (95% CI, 7.2-23.4). CONCLUSION: Second-degree relatives from families with the p16-Leiden mutation in CDKN2A have a considerably increased melanoma risk compared with the general population. IMPACT: This study provides justification for the surveillance of second-degree relatives from families with a CDKN2A germline mutation.