Residual disease detection using targeted parallel sequencing predicts relapse in cytogenetically normal acute myeloid leukemia

Despite achieving complete remission after intensive therapy, most patients with cytogenetically normal (CN) AML relapse due to the persistence of submicroscopic residual disease. In this pilot study, we hypothesized that detection of leukemia‐specific mutations following consolidation treatment using a targeted parallel sequencing approach predicts relapse. We included 34 AML patients of whom diagnostic material and remission bone marrow slides after at least one cycle of consolidation were available. Isolated DNA was screened for mutations in 19 genes using an Ion Torrent sequencing platform. Furthermore, the variant allelic frequency of distinct mutations was validated by digital PCR and sequencing using a barcoding approach. Twenty‐seven out of 34 patients could be analyzed for mutation clearance. We identified 68 somatic mutations at diagnosis (median, 3 mutations per patient; range 1‐5) and 22 of these were still detected in 16 patients after consolidation therapy with a reliable sensitivity of 0.5% (median, 1 mutation; range 0‐3). The most frequent noncleared mutations were found in DNMT3A. However, as persistence of these mutations has recently been shown to be without any impact on relapse risk, we performed survival and relapse risk analysis excluding DNMT3A mutations. Importantly, persistence of non‐DNMT3A mutations was associated with a higher risk of AML relapse (7/8 pts versus 6/19 pts; P = .013) and with a shorter relapse‐free survival (333 days vs. not reached; log‐rank P = .0219). Detection of residual disease by routine targeted parallel sequencing proved feasible and effective as persistence of somatic mutations other than DNMT3A were prognostic for relapse in CN AML.     

Changes in the temporomandibular joint position depending on the sagittal osteotomy technique and extent of mandibular movement

The bilateral sagittal split osteotomy (BSSO) and high oblique sagittal split osteotomy (HSSO) are common techniques for mandibular movement in orthognathic surgery. The aim of this study was to evaluate the influence of both techniques, as well as movement distances and directions, on the position of the temporomandibular joint (TMJ). A total of 80 mandibular movements were performed on 20 fresh human cadaver heads, four on each head. Pre- and postoperative cone beam computed tomography was used to plan the surgical procedure and analyse the TMJ. Reference measurements included the anterior, superior, and posterior joint spaces, intercondylar distances and angles in the axial and coronal planes, and the sagittal, coronal, and axial angulations of the proximal segment. Only minor differences were found between the BSSO and HSSO techniques, particularly in terms of the intercondylar angle in the axial plane (P < 0.03) and the condylar angle of the proximal segment in the sagittal plane (P < 0.011). Observed changes in the TMJ were mostly opposite when moving the mandible forwards and backwards and increased with increasing movement distance. BSSO and HSSO result in similar changes in TMJ position. The extent of the movement distance influences the position of the condyle more than the osteotomy technique.     

Interviews with patients with advanced cancer—another step towards an international cancer pain classification system

Purpose

Patients’ involvement in the development of assessment tools is recommended, and the European Palliative Care Research Collaborative has adhered to this when developing a shared language for cancer pain, an international assessment and classification system. Study objectives were to investigate how patients ranked the relevance of several previously identified pain domains, to investigate patients’ perception of the pain experience and to disclose additional, relevant pain domains for cancer pain classification to those identified in the literature.

Methods

Semistructured interviews with advanced cancer patients treated with opioids were performed and analysed verbatim. Patients scored the relevance of predefined pain domains on an 11-point Numerical Rating Scale.

Results

Thirty-three Norwegian and Austrian patients were included (16 females and 17 males); the mean age was 63?years, and the mean Karnofsky performance score was 65. The ranking of domains was as follows etiology (mean Numerical Rating Scale score, 8.5), duration (8.0), intensity (7.4), coping (7.1), physical (5.9) and psychological functioning (5.8). Sleep was identified as a new candidate domain to include in the system. The patients emphasised consequences of having pain, for example, poor physical functioning and psychological distress.

Conclusions

Previously identified pain domains were confirmed to be relevant to the patients; however, the ranking differed from the experts’ ranking. Sleep disturbances may be added as a domain in a future classification system.     

Neuropsychological outcomes of patients with low-grade glioma diagnosed during the first year of life

Journal of Neuro-Oncology - Low-grade gliomas (LGG) are a heterogeneous group of brain tumors, which are often assumed to have a benign course. Yet, children diagnosed and treated for LGG in...     

Rapid and reliable detection of LINE-1 hypomethylation using high-resolution melting analysis

Objectives

The aim of the present study was to evaluate the precision and reproducibility of the LINE-1 high-resolution melting (HRM) assay to detect LINE-1 hypomethylation.

Design and methods

We first evaluated a methylated DNA dilution matrix and a panel of human cancer cell lines. We then applied this LINE-1 HRM assay to a set of 37 archival prostate cancer tissue samples.

Results

Our LINE-1 HRM assay revealed small and reproducible run-to-run and bisulfite-to-bisulfite variations. As expected, we found a large variation in methylation levels between different cancer cell lines. All results were confirmed with MethyLight and pyrosequencing as indicated by the high correlation coefficient. Finally, we successfully applied the LINE-1 HRM assay to archival prostate cancer tissues.

Conclusions

The present LINE-1 HRM assay represents a novel, accurate, and cost-effective method to measure global hypomethylation, which makes it suitable for high- and low-throughput laboratories.     

PTCH promoter methylation at low level in sporadic basal cell carcinoma analysed by three different approaches

Please cite this paper as: PTCH promoter methylation at low level in sporadic basal cell carcinoma analysed by three different approaches. Experimental Dermatology 2010. Abstract: Basal cell carcinoma (BCC) is the most common form of skin cancer. Mutations of the PTCH hallmark gene are detected in about 50–60% of BCCs, which raises the question whether other mechanisms such as promoter methylation can inactivate PTCH. Therefore, we performed methylation analysis of the PTCH promoter in a total of 56 BCCs. The sensitivity of three different methods, including direct bisulphite sequencing PCR, MethyLight and high‐resolution melting (HRM), was applied and compared. We found that HRM analysis of DNA from fresh tissue [rather than formalin‐fixed and paraffin‐embedded tissue (FFPE)] was the most sensitive method to detect methylation. Low‐level methylation of the PTCH promoter was detected in five out of 16 analysed BCCs (31%) on DNA from fresh tissue but only in two (13%) samples on short‐time stored FFPE DNA from the very same tumors. In contrast, we were unable to detect methylation by HRM on long‐time stored DNA in any of the remaining 40 BCC samples. Our data suggest that (i) HRM on DNA extracted from fresh tissue is the most sensitive method to detect methylation and (ii) methylation of the PTCH promoter may only play a minor role in BCC carcinogenesis.     

The clinical features of polymerase proof-reading associated polyposis (PPAP) and recommendations for patient management

Familial Cancer - Pathogenic germline exonuclease domain (ED) variants of&nbsp;POLE&nbsp;and&nbsp;POLD1 cause the Mendelian dominant condition polymerase proof-reading associated...