Tumour‐associated mast cells in classical Hodgkin's lymphoma: correlation with histological subtype,other tumour‐infiltrating inflammatory cell subsets and outcome

The tumour microenvironment in classical Hodgkin's lymphoma (cHL) is characterised by a minor population of neoplastic Hodgkin and Reed–Sternberg cells within a heterogeneous background of non‐neoplastic bystanders cells, including mast cells. The number of infiltrating mast cells in cHL has been reported to correlate with poor prognosis. We used immunohistochemistry to assess the degree of tumour‐infiltrating mast cells in cHL tissue microarrays and correlated this with clinico‐pathological features and prognosis in a cohort of homogeneously treated patients with Hodgkin's disease. A high degree of tumour mast cells was associated with nodular sclerosis (NS) subtype histology (P = 0.0002). Moreover, the number of mast cells was inversely correlated with the numbers of CD68+ and CD163+ macrophages (P = 0.0001 and P = 0.003, respectively) and with the number of granzyme+ cytotoxic cells (P = 0.004). The degree of mast cell infiltration was not a prognostic factor in cHL of nodular sclerosis subtype. In contrast, in mixed cellularity cHL a high number of intratumoral mast cells correlated with significantly poorer outcome both in terms of overall (P = 0.03) and event‐free survival (P = 0.01). Further studies are warranted into the biological mechanisms underlying this adverse outcome and their possible therapeutic implications.     

Targeted ultradeep next‐generation sequencing as a method for KIT D816V mutation analysis in mastocytosis

Next‐generation sequencing (NGS) is becoming increasingly used for diagnostic mutation analysis in myeloid neoplasms and may also represent a feasible technique in mastocytosis. However, detection of the KIT D816V mutation requires a highly sensitive method in most patients due to the typically low mutation levels. In this study, we established an NGS‐based KIT mutation analysis and analyzed the sensitivity of D816V detection using the Ion Torrent platform. Eighty‐two individual NGS analyses were included in the study. All samples were also analyzed using highly sensitive KIT D816V mutation‐specific qPCR. Measurements of the background level in D816V‐negative samples supported a cutoff for positivity of 0.2% in three different NGS panels. Clinical samples from patients with SM that tested positive using qPCR with a D816V allele burden >0.2% also tested positive using NGS. Samples that tested positive using qPCR with an allele burden <0.2% tested negative using NGS. We thereby demonstrate that caution should be taken when using the potentially very sensitive NGS technique for KIT D816V mutation analysis in mastocytosis, as many patients with SM have D816V mutation levels below the detection limit of NGS. A dedicated and highly sensitive KIT D816V mutation analysis therefore remains important in mastocytosis diagnostics.     

Risk factors in transient osteoporosis: a retrospective study on 23 cases

The aim of this study is to verify the prevalence of risk factors for transient osteoporosis (TO) in a cohort of patients selected by strict diagnostic criteria. Retrospective observational cohort study on outpatients’ data. Inclusion criteria were: (1) acute onset of pain at a lower limb joint exacerbated by weight bearing; (2) no history of trauma, tumors, rheumatic diseases, or infection; (3) presence bone marrow edema on MRI in a weight bearing joint without signs of intraarticular lesions; (4) no hyperesthesia and/or allodynia and/or sweeting changes. The following risk factors were search for in all patients: (1) previous episode of TO; (2) disorders of bone metabolism; (3) cigarette smoke; (4) sudden lower limb overuse; (5) presence of osteoporosis/osteopenia. Twenty-three patients (8 females, 15 males, mean age 48.4 years) fulfilled the inclusion criteria. An average of 1.96 risk factors for TO was present in the cohort. The most frequent risk factor was overuse (in 15 patients, 65.2 %) and the second risk factor was bone metabolism disorders (in 10 patients, 43.5 %). Seven patients (30.4 %) were heavy smokers (more than 20 cigarettes per day) and seven patients showed a previous episode of TO. Six patients (26.1 % of the overall cohort but 60 % of those investigated with DEXA) resulted osteoporotic or osteopenic. Our results suggest there are risk factors that must be investigated in these patients. The presence of these risk factors might support the thesis that their disorder is tied to a decoupling between microdamage accumulation and self-reparative ability of bone tissue. The identification of risk factors with a precise diagnostic pathway can accelerate the diagnostic process and reduce recurrences.