Clinical neuropathology practice guide 3-2013: levels of evidence and clinical utility of prognostic and predictive candidate brain tumor biomarkers.

A large number of potential tissue biomarkers has been proposed for brain tumors. However, hardly any have been adopted for routine clinical use, so far. For most candidate biomarkers substantial controversy exists with regard to their usefulness in clinical practice. The multidisciplinary neurooncology taskforce of the Vienna Comprehensive Cancer Center Central Nervous System Unit (CCC-CNS) addressed this issue and elaborated a four-tiered levels-of-evidence system for assessing analytical performance (reliability of test result) and clinical performance (prognostic or predictive) based on consensually defined criteria. The taskforce also consensually agreed that only biomarker candidates should be considered as ready for clinical use, which meet defined quality standards for both, analytical and clinical performance. Applying this levels-of-evidence system to MGMT, IDH1, 1p19q, Ki67, MYCC, MYCN and ß-catenin, only immunohistochemical IDH1 mutation testing in patients with diffuse gliomas is supported by sufficient evidence in order to be unequivocally qualified for clinical use. For the other candidate biomarkers lack of published evidence of sufficiently high analytical test performance and, in some cases, also of clinical performance limits evidence-based confirmation of their clinical utility. For most of the markers, no common standard of laboratory testing exists. We conclude that, at present, there is a strong need for studies that specifically address the analytical performance of candidate brain tumor biomarkers. In addition, standardization of laboratory testing is needed. We aim to regularly challenge and update the present classification in order to systematically clarify the current translational status of candidate brain tumor biomarkers and to identify specific research needs for accelerating the translational pace.

Clinical Neuropathology Practice News 4-2012: levels of evidence for brain tumor biomarkers.

The National Comprehensive Cancer Network (NCCN) recently published a task force report on the evaluation of the clinical utility of tumor biomarkers in oncology. In this report, common terminology and the use of levels of evidence scores to aid the evaluation of biomarker tests in oncology were proposed. Furthermore, the task force applied a level of evidence system to selected biomarkers of several cancer types. According to this system, the highest level of evidence, IA, is granted to a biomarker only if it has been evaluated in at least one adequately powered and specifically designed prospective controlled trial. For gliomas, only 1p/19q testing in oligodendroglial tumors was classified as IA by the NCCN task force. For all of the following biomarkers the present evidence level for clinical utility was regarded as lower than that of 1p/19q status: MGMT gene promoter methylation testing (glioblastoma), IDH mutation testing (diffusely growing gliomas), BRAF fusion testing (pilocytic astrocytoma) and CIMP testing (diffusely growing gliomas). The task force acknowledged that the exact application of levels of evidence needs further refinement. To our mind, the implementation of a brain tumor expert panel seems vital to evaluate the evidence levels of neurooncological biomarkers according to generally accepted criteria on a regular basis. Systematic identification of current research needs and widely accepted up-to-date recommendations for efficient biomarker application in everyday practice could be gained.

Hypothyroidism in patients with renal cell carcinoma: blessing or curse?

BACKGROUND: Sunitinib and sorafenib are tyrosine kinase inhibitors that have important antitumor activity in metastatic renal cell carcinoma (mRCC). Hypothyroidism constitutes a commonly reported side effect of both drugs, and particularly of sunitinib. The objective of this analysis was to investigate whether the occurrence of hypothyroidism during treatment with sunitinib and sorafenib affects the outcome of patients with mRCC. METHODS: Eighty-seven consecutive patients with mRCC who were to receive treatment with sunitinib or sorafenib were included in a prospective analysis. Thyroid function was assessed in each patient every 4 weeks during the first 2 months of treatment and every 2 to 4 months thereafter. Assessment included serum levels of thyroid-stimulating hormone (TSH), tri-iodthyronine (T3), and thyroxine (T4). Subclinical hypothyroidism was defined as an increase in TSH above the upper limit of normal (>3.77 µM/mL) with normal T3 and T4 levels. RESULTS: Subclinical hypothyroidism was evident in 5 patients at baseline and occurred in 30 patients (36.1%) within the first 2 months after treatment initiation. There was a statistically significant correlation between the occurrence of subclinical hypothyroidism during treatment and the rate of objective remission (hypothyroid patients vs euthyroid patients: 28.3% vs 3.3%, respectively; P < .001) and the median duration of survival (not reached vs 13.9 months, respectively; hazard ratio, 0.35; 95% confidence interval, 0.14-0.85; P = .016). In multivariate analysis, the development of subclinical hypothyroidism was identified as an independent predictor of survival (hazard ratio, 0.31; P = .014). CONCLUSIONS: The current results indicated that hypothyroidism may serve as a predictive marker of treatment outcome in patients with mRCC. Thus, the interpretation of hypothyroidism during treatment with sunitinib and sorafenib as an unwanted side effect should be reconsidered.

Perioperative auricular electroacupuncture has no effect on pain and analgesic consumption after third molar tooth extraction.

BACKGROUND: Auricular acupuncture (AA) has been shown to alleviate acute and chronic pain. We investigated the effects of auricular electroacupuncture (AE) on pain and analgesic drug consumption in the first 48 h after unilateral mandibular third molar tooth extraction under local anesthesia in a prospective, randomized, double-blind, placebo-controlled study in 149 patients. METHODS: Patients received either AA with electrical stimulation (AE, n = 76) or without (AA, n = 37) electrical stimulation at an alternating frequency of 2/100 Hz or a sham AE with metal plates instead of needles and no electrical stimulation, no-needle (NN, n = 36) at the AA points 1 (tooth), 55 (Shen men) and 84 (mouth) during the entire study period. Regularly rated pain intensity (five-point verbal rating scale), consumption of acetaminophen 500 mg tablets and additional rescue medication with mefenamic acid 500 mg were assessed. RESULTS: The median fraction of time when pain was rated as moderate or worse (upper and lower quartile): AE: 33% (12%, 64%), AA: 22% (6%, 56%), NN: 30% (7%, 53%) did not differ significantly among the treatment groups. There were no significant differences in mean number of acetaminophen 500 mg tablets (range): AE: 5.2 (0-12), AA: 4.6 (0-11), NN: 5.4 (0-10) or percentage of patients requiring additional mefenamic acid: AE: 19%, AA: 18%, NN: 19%. CONCLUSION: We conclude that neither AE nor AA alone reduce either pain intensity or analgesic consumption in a molar tooth extraction model of acute pain.