Diffusion-weighted imaging using 3.0 T MRI as a possible biomarker of renal tumors.

BACKGROUND/AIM: Diffusion-weighted imaging (DWI) allows for differentiation of benign from malignant tumors, histological tumor types and their grade. The aim of the study was to evaluate the capabilities of DWI using 3 Tesla Magnetic resonance imaging (3T MRI) in the preoperative assessment of renal tumors. PATIENTS AND METHODS: This retrospective study included 143 tumors in 139 patients (130 malignant tumors and 13 benign tumors) that were examined using DWI with b values of 50, 400 and 800 s/mm(2). In all tumors, the lowest value of apparent diffusion coefficient (ADC) in the solid tissue was measured and correlated with the histological finding. RESULTS: A significant difference between ADCs of malignant and benign tumors was found (p<0.001). Comparison of the most common malignant and benign tumors clear-cell renal carcinoma (CCRCC) grade I and oncocytoma resulted in a difference of borderline significance with a marked overlap (p=0.046). By assessing the histological types of malignant tumors, we detected a significant difference between CCRCC and all other histological types (p=0.048 for chromophobe (CH) RCC, p=0.002 for papillary (P) RCC and p=0.002 for urothelial carcinoma (UC)). Mutual differentiation of other types of carcinomas was not feasible (p=1.0 in all cases). The differences between low-grade (grade I+II) and high-grade (grade III+IV) CCRCC was significant (p<0.001). A significant difference was found even between CCRCC grade I and others (p=0.01 for grade II, p<0.001 for grade III+IV, respectively). CONCLUSION: DWI may contribute in distinguishing CCRCC from other histological types and to determinits grade. The method has certain potential for distinguishing benign from malignant tumors; however, differentiation of the most frequently represented types, CCRCC grade I and oncocytoma, remains difficult.

Microarray analysis of serum mRNA in patients with head and neck squamous cell carcinoma at whole-genome scale.

With the increasing demand for noninvasive approaches in monitoring head and neck cancer, circulating nucleic acids have been shown to be a promising tool. We focused on the global transcriptome of serum samples of head and neck squamous cell carcinoma (HNSCC) patients in comparison with healthy individuals. We compared gene expression patterns of 36 samples. Twenty-four participants including 16 HNSCC patients (from 12 patients we obtained blood samples 1 year posttreatment) and 8 control subjects were recruited. The Illumina HumanWG-6 v3 Expression BeadChip was used to profile and identify the differences in serum mRNA transcriptomes. We found 159 genes to be significantly changed (Storey's P value <0.05) between normal and cancer serum specimens regardless of factors including p53 and B-cell lymphoma family members (Bcl-2, Bcl-XL). In contrast, there was no difference in gene expression between samples obtained before and after surgery in cancer patients. We suggest that microarray analysis of serum cRNA in patients with HNSCC should be suitable for refinement of early stage diagnosis of disease that can be important for development of new personalized strategies in diagnosis and treatment of tumours but is not suitable for monitoring further development of disease.

Influence of radiofrequency surgery on architecture of the palatine tonsils.

Radiofrequency surgery is a widely used modern technique for submucosal volume reduction of the tonsils. So far there is very limited information on morphologic changes in the human tonsils after radiofrequency surgery. We performed histopathological study of tonsillectomy specimens after previous bipolar radiofrequency induced thermotherapy (RFITT). A total of 83 patients underwent bipolar RFITT for hypertrophy of palatine tonsils. Tonsil volume reduction was measured by 3D ultrasonography. Five patients subsequently underwent tonsillectomy. Profound histopathological examination was performed to determine the effect of RFITT on tonsillar architecture. All tonsillectomy specimens showed the intact epithelium, intact germinal centers, normal vascularization, and no evidence of increased fibrosis. No microscopic morphological changes in tonsillectomy specimens after bipolar RFITT were observed. RFITT is an effective submucosal volume reduction procedure for treatment of hypertrophic palatine tonsils with no destructive effect on microscopic tonsillar architecture and hence most probably no functional adverse effect.

A role of multifactorial evaluation of prostatic 3T MRI in patients with elevated prostatic-specific antigen levels: prospective comparison with ultrasound-guided transrectal biopsy.

AIM: To assess the role of multiparametric 3T magnetic resonance (3TMRI) of the prostate in detection of the prostatic carcinoma in a male population with elevated prostatic-specific antigen (PSA) and to compare the results with those of transrectal biopsies. MATERIALS AND METHODS: A prospectively collected cohort of 191 men underwent 3T MRI before transrectal biopsy. The evaluation consisted of the assessment of T2-weighted images, diffusion-weighted images, MR spectroscopy and the pharmacokinetic evaluation of the data obtained during the dynamic post-contrast T1 imaging. The assessment included the calculation of the blood volume and transfer constant evaluations. The diagnosis of prostate carcinoma was based on a minimum of three positive signs obtained from MR studies--hypointensive T2 lesion, diffusion restriction, elevated choline/creatine peak in spectrum and malignant type of saturation by contrast agents. All biopsies were evaluated by a specialist in uropathology. RESULTS: 164 patients underwent biopsy, in 27 the biopsy was omitted due to a lack or low probability of carcinoma: Overall, 84 carcinomas were found. Based on the comparison of biopsy results, 3T MRI reached a sensitivity of 97.6%, specificity of 85.0%, positive predictive value of 74.6% and negative predictive value of 96,3% respectively. There were only three false negative findings. In three patients with very suspicious MRI findings and PSA levels over 30 ng/ml, the biopsy did not confirm carcinoma, even though it was highly suspected. CONCLUSION: The implementation of 3T MRI in routine assessment of patients with elevated PSA should reduce the number of biopsies performed and improve the number of tumors detected due to better targeted biopsies.

Combined bipolar radiofrequency surgery of the tongue base and uvulopalatopharyngoplasty for obstructive sleep apnea.

INTRODUCTION: The aim of the study was to investigate the effectiveness of combined bipolar radiofrequency surgery of the tongue base (RFBT) and uvulopalatopharyngoplasty (UPPP) in a single session for obstructive sleep apnea and whether this combination is safe and well tolerated. MATERIAL AND METHODS: Seventy-nine patients with obstructive sleep apnea and both palatal and retroglossal obstruction underwent UPPP with bipolar RFBT. The control group consisted of 35 patients treated by UPPP alone. RESULTS: The apnea-hypopnea index significantly decreased from 28.7 to 14.1. The oxygen desaturation index decreased from 15.1 to 10.3. Mean oxygen saturation was unchanged. Subjectively, the Epworth Sleepiness Scale was significantly improved from 10.6 to 7.3, and the snoring level decreased from 8.4 to 6.0. The overall treatment success rate increased from 41.9% for UPPP alone to 51.7% for UPPP + RFBT. No serious adverse events occurred. Two patients had postoperative bleeding from the tonsillar bed after UPPP. Four patients had ulceration of the base of the tongue after RFBT with spontaneous cure. One patient had a taste change in half of the tongue that resolved within two months. CONCLUSIONS: Combined bipolar RFBT and UPPP in a single session is well tolerated and safe surgery in the treatment of obstructive sleep apnea. It is effective in reducing respiratory parameters and subjective symptoms of obstructive sleep apnea. Further advantages are a single session, simple feasibility, bipolar technique and short time of the procedure.

Orbital and intracranial complications after acute rhinosinusitis.

BACKGROUND/OBJECTIVES: Nowadays, intracranial abscess is a rare complication of acute rhinosinusitis. The consequent orbital and intracranial complications of acute rhinosinusitis are rare but must be mutually excluded in complicated rhinosinusitis even when proper surgical and medical treatment tend to efficiently heal the orbital complication. METHODS: We report a case of a patient who primarily revealed symptoms of orbitocellulitis as a complication of odontogenous rhinosinusitis. Proper diagnostic and therapeutical measures were undertaken to manage the disease immediately after stationary admission. RESULTS: Two weeks after an inconspicuous healing period, hemiparesis due to formation of an intracranial abscess developed. An emergent situation reveals which was unusual to the clinical situation. CONCLUSION: The possible role of underlying mechanisms of intracranial abscess formation is discussed and review of literature concerning orbital and intracranial rhinosinusitis complications is performed. The correct indication of imaging methods and accurate evaluation of diminutive symptoms are essential. We assume that performance of a complementary CT of the brain or MRI even when previous CT scan of the orbit/paranasal sinuses reveals no cerebral pathology should be done to avoid or minimize future patients with consecutive orbital and intracranial complications of acute rhinosinusitis.

Diffusion tensor magnetic resonance imaging of glial brain tumors.

AIM: To evaluate the author's experience with the use of diffusion tensor magnetic resonance imaging (DTI) on patients with glial tumors. METHODS: A retrospective evaluation of a group of 24 patients with glial tumors was performed. There were eight patients with Grade II, eight patients with Grade III and eight patients with Grade IV tumors with a histologically proven diagnosis. All the patients underwent routine imaging including T2 weighted images, multidirectional diffusion weighted imaging (measured in 60 non-collinear directions) and T1 weighted non-enhanced and contrast enhanced images. The imaging sequence and evaluation software were produced by Massachusetts General Hospital Corporation (Boston, MA, USA). Fractional anisotropy (FA) maps were calculated in all patients. The white matter FA changes were assessed within the tumorous tissue, on the tumorous borderline and in the normally appearing white matter adjacent to the tumor. A three-dimensional model of the white matter tract was created to demonstrate the space relationship of the tumor and the capsula interna or corpus callosum in each case using the following fiber tracing parameters: FA step 0.25 and a tensor declination angle of 45 gr. An additional assessment of the tumorous tissue enhancement was performed. RESULTS: A uniform homogenous structure with sharp demargination of the Grade II tumors and the wide rim of the intermedial FA in all Grade III tumors respectively, were found during the evaluation of the FA maps. In Grade IV tumors a variable demargination was noted on the FA maps. The sensitivity and specificity for the discrimination of low- and high-grade glial tumors using FA maps was revealed to be 81% and 87% respectively. If the evaluation of the contrast enhancement was combined with the evaluation of the FA maps, both sensitivity and specificity were 100%. CONCLUSION: Although the evaluation of the fractional anisotropy maps is not sufficient for glioma grading, the combination of the contrast enhancement pattern and fractional anisotropy maps evaluation improves the possibility of distinguishing low- and high-grade glial tumors. Three-dimensional models of the white matter fibers in the corpus callosum and the internal capsule may be used in the presurgical planning.

Evaluation of microsatellite amplifications at chromosomal locus 3q26 as surrogate marker for premalignant changes in mucosa surrounding head and neck squamous cell carcinoma.

We analyzed tumor and surrounding mucosal samples of head and neck squamous cell carcinoma by fragment analysis for gain of genomic material as a potential indicator for oncogenic transformation. Our aim was to evaluate the potential value of this fast and sensitive polymerase chain reaction (PCR)-based method for intra-operative detection of chromosomal aberrations as a surrogate marker for incomplete tumor resection. Biopsies of the primary tumors and adjacent macroscopically nonmalignant mucosa 1 and 2 cm away from the tumor margins were collected from 20 patients. DNA were isolated, and 11 microsatellite markers at loci 3q25.31 approximately 3q28 were amplified by PCR. Allelic losses or gains were analyzed by capillary electrophoresis. Imbalanced alleles were common in the samples evaluated. In the median gains of the informative loci were detected in 67% of the primary tumors, 22% of the samples taken at 1 cm and 15% of the samples taken at 2 cm distance. We observed gains of 3q at least in one microsatellite in all primary tumors, in 15 (1 cm) and 12 (2 cm) nonmalignant mucosa samples. Gain of genetic material is frequent in tumor-surrounding mucosa. Detection of small chromosomal aberrations is possible using the PCR-based, highly sensitive, and fast-to-perform fragment analysis technique. The value for the diagnosis and prognosis will have to be proven in follow-up studies.