Search

Personalized medicine and treatment stratification of patients with head and neck squamous cell carcinoma (HNSCC) today mostly ignore genetic heterogeneity in HNSCC but especially the patient's genetic background. We hypothesized that particular human leukocyte antigen (HLA) class I (HLA-A, B, Cw) and II proteins (DR, DQ) confer susceptibility for and influence development of HNSCC and may be prognostic factors for progression-free survival (PFS).90 consecutive HNSCC patients of the prospective observational cohort study LIFE treated between 08/2010 and 05/2011 at the University Leipzig underwent low resolution typing of HLA-A, B, Cw, DR, and DQ. Antigen and haplotype frequencies were compared to those in German blood donors. Effects on PFS were analyzed using Kaplan-Meier curves and Cox models.HNSCC patients had overall altered HLA-B frequencies (P0.05); frequencies of B∗44 were lower, those of B∗13, B∗52, and B∗57 increased (P0.05). Almost all other antigen frequencies showed no deviation. Homozygous HLA-Cw and DRB4 were frequent and associated with reduced PFS (P0.05). Altered haplotype frequencies were common and particular haplotypes accompanied by differing PFS. B∗13/Cw∗06 carriers had poorest outcome (P=0.011). However, multivariate Cox proportional hazard models revealed 3 clinical covariates (localization oropharynx, loco-regional metastasis, and T4 category), HPV16-DNA positivity, and 10 HLA traits as independent predictors for PFS.The relevance of the genetic background of HNSCC patients calls for future research to clarify the role of HLA traits in HNSCC and if PFS depends on HLA.

First CT-based navigation in ENT was established 20 years ago. Today, navigation systems display current 3D information of a pointing device within preoperatively generated volume CT scans. In the literature, the manufacturer's guide and protocols of certification we found divergent statements describing the accuracy of such systems, ranging from 1 to 9 mm. Often in an uncritical way, various variables are used in order to describe the accuracy. It seems to be obvious that straight criteria in evaluating navigational systems are missing. A unitary understanding for the term accuracy is non-existent in clinical practice. Furthermore, in the literature we found the incorrect equality for the terms precision and accuracy. The available literature on evaluating CAS-Systems was analysed. Then, the terms precision and accuracy were differentiated from established technical definitions. Using this perception, the term surgical accuracy was derived and suggested. In conclusion, the results were applied to our own study evaluating a navigation system. Precision is understood as the internal accuracy of measurements which is received through repeated measurements under equal conditions. It strongly depends on the sturdiness of the measuring instrument. In contrast, accuracy usually stands for an external accuracy under different circumstances. In metrology, the accuracy of measurements is affected by the impacts of all random components and systematic errors. From a technical and general perspective, accuracy is defined to be an approximation to a certain expected value. In a clinical setup it depends on the clinical requirements. The surgical accuracy of a navigation system should be informative about the maximum target positioning deviation, the arithmetic mean, the standard deviation and the number of measurements. An accepted reference value for deviation should be stated.