The Effect of Chitohem Bleeding Inhibitor Powder on Pain and Bleeding After Tonsillectomy by Suturing Method.

Study Design and Objectives: This study aimed to investigate Triamcinolone ointment's effect on pain and bleeding after tonsillectomy by suturing method. Methods: The present study was performed as a single-blind clinical trial on 200 patients who underwent a total tonsillectomy in the ENT department of Loghman Hakim Hospital in Tehran during 2016. Candidates for total tonsillectomy were randomized into 2 groups one by one. Participants were randomly divided into 2 groups. Both groups matched homologically. Patients in both groups (intervention and control) underwent cold dissection total tonsillectomy. In addition to suturing, in the intervention group, Triamcinolone ointment was used to control the local bleeding at the surgical site. In the control group, only sutures were used to control bleeding. The studied variables included: bleeding and pain 24 hours after surgery, Time to start oral feeding. Result: The frequency of bleeding cases in the first 24 hours are included: 4 patients (5.63%) in the intervention group and 6 patients (8.45%) in the control group (P = 0.01). The average time to start eating for patients who were treated with topical triamcinolone ointment was significantly less than those who were not treated with this ointment. Only 2 patients (2.77%) in the intervention group took analgesics in the first 24 hours after surgery, while and 11 patients (15.3%) in the control group received analgesics in the same time period. Conclusion: In general, the results of this study showed that the use of Triamcinolone ointment in total tonsillectomy could reduce bleeding, analgesics usage, and the time of feeding onset.

Image-guided interstitial high-dose-rate brachytherapy in the treatment of inoperable recurrent head and neck malignancies: An effective option of reirradiation.

BACKGROUND: In recurrent head and neck cancer, therapeutic options are limited and high-quality evidence is rare. The purpose of this report was to present our experience of CT-guided interstitial high-dose rate (HDR) brachytherapy in 4 challenging cases of inoperable recurrent head and neck cancer. METHODS: A 53-year-old man with mucosal melanoma of the paranasal sinuses, a 61-year-old man with myofibroblastic sarcoma of the nasal cavity, a 51-year-old woman with nasopharyngeal cancer, and a 44-year-old woman with orbital leiomyosarcoma were treated with reirradiation by HDR brachytherapy after previous comprehensive therapy, including full course external radiotherapy (RT). RESULTS: All patients showed response to brachytherapy with 1 patient experiencing locoregional failure. The mean lesion-specific disease control was 15 months. Currently, 1 patient is alive and 3 patients died after mean 20 months after treatment. CONCLUSION: In patients with inoperable recurrent head and neck cancer, CT-guided interstitial HDR brachytherapy can play a role in providing palliation and tumor control. © 2017 Wiley Periodicals, Inc. Head Neck 39: E61-E68, 2017.

Heterogeneity of primary site biopsies in head and neck squamous cell carcinoma.

AIM: There is no common standard defining how biopsies for translational research purposes should be performed. In our study, the impact of two different biopsy methods on the results of immunohistochemical staining of the samples for epidermal growth factor receptor (EGFR) and the proliferation antigen Ki-67 were evaluated. PATIENTS AND METHODS: Twenty-four patients who underwent surgical treatment of their HNSCC tumour were included. From each surgically resected tumour, one superficial biopsy and one core-needle biopsy through the cross-section of the tumour were taken. As a positive control, a tissue slide through the primary tumour was made. RESULTS: The analysis showed that neither the superficial nor the core biopsy expression of EGFR correlated significantly with that of the tumour. The analysis showed that the superficial biopsy expression of Ki-67 correlated significantly with that of tumour. CONCLUSION: Translational research projects based on biopsy tissues should be using whole surgical resection specimens of a tumour.

Hypofractionated accelerated CT-guided interstitial ¹9²Ir-HDR-Brachytherapy as re-irradiation in inoperable recurrent cervical lymphadenopathy from head and neck cancer.

BACKGROUND: Despite significant improvements in the treatment of head and neck cancer (HNC), lymph node recurrences remain a clinical challenge after primary radiotherapy. The value of interstitial (IRT) brachytherapy (BRT) for control of lymph node recurrence remains unclear. In order to clarify its role a retrospective review was undertaken on the value of computed tomography (CT)-guided IRT high-dose-rate (HDR)-BRT in isolated recurrent disease from HNC. PATIENTS AND METHODS: From 2000 to 2007, 74 patients were treated for inoperable recurrent cervical lymphadenopathy. All patients had previously been treated with radical radiotherapy or chemoradiation with or without surgery. The HDR-BRT delivered a median salvage dose of 30.0 Gy (range, 12.0-36.0 Gy) in twice-daily fractions of 2.0-5.0 Gy in 71 patients and of 30.0 Gy (range, 10.0-36.0 Gy) in once-daily fractions of 6.0-10.0 Gy in three patients. RESULTS: The overall and disease-free survival rates at one, two and three years were 42%, 19%, 6%, and 42%, 37% and 19%, respectively. The local control probability at one, two and three years was 67% at all three time points. Grade III-IV complications occurred in 13% of patients. CONCLUSIONS: In patients with inoperable recurrent neck disease from HNC, hypofractionated accelerated CT-guided IRT-HDR-BRT can play an important role in providing palliation and tumor control.

Does dexamethasone inhibit anticancer activity of cetuximab in squamous cell carcinoma cell lines of the head and neck?

Glucocorticoids such as dexamethasone are widely used as comedication in the treatment of head and neck cancer, e.g., to improve appetite and decrease weight loss and fatigue in patients with advanced disease or as antiallergic and antiemetic prophylaxis during anti-EGFR therapy. However, the literature suggests that dexamethasone induces resistance to antineoplastic agents in many solid tumor models in vitro and in vivo. Since this phenomenon has never been investigated in head and neck cancer, the present study was conducted to investigate the effect of dexamethasone on the antiproliferative activity of cetuximab in vitro in squamous cell carcinoma of the head and neck (SCCHN) cell lines. The antiproliferative effect of the anti-EGFR agent cetuximab alone and in combination with increasing concentrations of dexamethasone was examined in eight SCCHN cell lines at three different time-points (24, 48 and 72 h). Cell growth inhibition and viability were measured quantitatively using WST and LDH assays. Absolute tumor cell numbers were determined by cell counting in a Rosenthal chamber. Cetuximab alone inhibited the growth of all eight SCCHN cell lines significantly (p=0.008). In some cases the addition of dexamethasone reduced the antiproliferative activity of cetuximab (p

Tracer kinetics analysis of dynamic contrast-enhanced CT and MR data in patients with squamous cell carcinoma of the upper aerodigestive tract: comparison of the results.

PURPOSE: (i) To evaluate the feasibility of tracer kinetics analysis of dynamic contrast-enhanced (DCE) CT and T2-weighted MR data of squamous cell carcinoma (SCCA) of the upper aerodigestive tract. (ii) To compare functional parameters derived by both modalities and examine the interchangeability of them as well as the intra- and inter-rater agreement. MATERIALS AND METHODS: Dynamic contrast-enhanced-CT and MR images of 23 patients with SCCA were postprocessed using a distributed-parameter (DP) tracer kinetic model. The evaluated parameters included blood flow (F), intravascular blood volume (v(1)), extravascular extracellular blood volume (v(2)), intravascular mean transit time (t(1)), lag time (t(0)), permeability surface area product (PS) and extraction ratio (E). Mean perfusion values, based on region-of-interest analysis, of the tumors and the healthy muscle tissue were compared and correlated. Inter-rater and intra-rater variability were assessed. Interchangeability of the tumor functional parameters was tested using Pearson's correlation coeficients and Bland-Altman plots. RESULTS: The mean values in tumor and healthy muscle tissues were significantly different for each modality (0.0001< or =P< or =0.03). The mean values of all tumor perfusion parameters apart from v(2) and E were significantly different (0.001< or =P< or =0.009) between the two modalities. The intra-rater variability was good to very good for all parameters. The inter-rater variability was moderate to good. Bland-Altman plots of F, t(1), t(0), and v(2) showed moderate interchangeability. There was a proportionality error in v(1) and PS graphs. CONCLUSION: The estimation of functional parameters in SCCA is feasible using DCE-CT and -MR with a DP model. The parameters are mostly significantly different and the interchangeability of them is limited.

Cetuximab enhances the efficacy of bortezomib in squamous cell carcinoma cell lines.

PURPOSE: Proteasome inhibition has been shown to be effective in multiple myeloma and solid tumor models. In this in vitro study, we investigated the antitumor effect of bortezomib (Velcade) in combination with cetuximab in squamous cell carcinoma cell lines (SCC). METHODS: Dose-escalation studies were performed in five squamous cell carcinoma cell lines using bortezomib or cetuximab alone or in combination. Cell survival and growth inhibition were measured quantitatively using an MTT and LDH assay. RESULTS: Bortezomib alone showed a significant antiproliferative activity in all SCC cell lines (P < 0.042), and the activity was further significantly enhanced by the addition of cetuximab (P < 0.043). CONCLUSIONS: Our results indicate that cetuximab increases the cytotoxic activity of bortezomib in SCC cell lines. Combination therapy of SCC with bortezomib and cetuximab might be less toxic than conventional drug regimens used in the treatment of these tumors.

Dynamic contrast-enhanced CT of head and neck tumors: comparison of first-pass and permeability perfusion measurements using two different commercially available tracer kinetics models.

RATIONALE AND OBJECTIVES: To evaluate the interchangeability of perfusion parameters between two software packages for the postprocessing of dynamic contrast-enhanced (DCE) computed tomographic images of head and neck tumors. MATERIALS AND METHODS: DCE computed tomographic images of 75 patients with head and neck tumors were postprocessed using a software package based on the maximum-slope approach and Patlak analysis, as well as a software package with deconvolution-based analysis incorporating an adiabatic approximation of tissue homogeneity (ATH) model. The evaluated perfusion parameters included blood flow (F), blood volume (v), and permeability-surface area product (PS). Region-of-interest (ROI) analysis of the tumors and the metastatic lymph nodes was performed. The perfusion parameters were compared using the Wilcoxon matched-pairs test and Bland-Altman plots. RESULTS: One hundred fifty-two ROIs of tumors and nodes were outlined and analyzed. Moderate to good correlations were demonstrated between the various perfusion values (r = 0.56-0.72, P < .0001). The Wilcoxon test revealed a significant difference between the two methods (P < .001), with the F, v, and PS values obtained using the maximum-slope approach and Patlak analysis higher than those obtained using deconvolution-based analysis with the assumptions of the ATH model. The Bland-Altman plots for F and v values revealed a proportionality trend with outliers, which were strongly associated with the magnitudes of the parameters. Analysis of the PS values did not show any systematic bias. CONCLUSION: There were significant differences in the perfusion parameters obtained using the two software packages, and thus, these parameters are not directly interchangeable.

Effects of combination treatment of bortezomib and dexamethasone in SCCHN cell lines depend on tumor cell specificity.

Bortezomib has recently become the new treatment standard for relapsed or refractory multiple myeloma. We previously demonstrated that bortezomib also had a significant growth-inhibiting and apoptotic effect on squamous cell carcinoma of the head and neck (SCCHN) cells in vitro. Preclinical evidence has provided a rationale for combining bortezomib with dexamethasone in multiple myeloma, suggesting that the therapeutic effects of the two agents might be additive. These findings are in contrast with the results achieved in solid tumor models where the addition of dexamethasone reduced the efficacy of other antineoplastic drugs. In the present study, we investigated the effect of dexamethasone in combination with bortezomib in SCCHN cell lines for the first time. The antiproliferative effect of bortezomib alone or in combination with increasing concentrations of dexamethasone was investigated in four SCCHN cell lines. Cell growth inhibition and viability were measured quantitatively using WST and LDH assays. Bortezomib alone inhibited the growth of all four SCCHN cell lines significantly (p<0.047). The addition of dexamethasone leads to a clear tumor cell decline and showed a trend in enhancing the growth-inhibitory effect of bortezomib although the difference failed to reach statistical significance (p>0.05). Our first results show that dexamethasone increased the cytotoxic activity of bortezomib in most SCCHN cell lines investigated. These findings might be dependent on molecular factors such as the degree of tumor cell differentiation and proliferation rate. Therefore, further studies will be required to elucidate these molecular factors to substantiate our findings from a cancer biological point of view.

Effect of bortezomib and cetuximab in EGF-stimulated HNSCC.

BACKGROUND: Proteasome inhibition has been shown to be effective in multiple myeloma and solid tumor models. In this in vitro study, the antitumor effect of bortezomib (Velcade) in combination with cetuximab was investigated in epidermal growth factor (EGF)-stimulated head and neck squamous cell carcinoma cell lines (HNSCC). MATERIALS AND METHODS: Dose escalation studies were performed with five EGF-stimulated squamous cell carcinoma cell lines using bortezomib alone or in combination with cetuximab. Growth inhibitory and cell decline effects were measured quantitatively using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) and lactate dehydrogenase (LDH) assay. RESULTS: Bortezomib alone showed no significant antiproliferative activity in any EGF-stimulated HNSCC cell line (p > 0.05), whereas the combination of bortezomib and cetuximab had highly significant antitumoral activity (p < 0.043). CONCLUSION: Our results indicate that cetuximab increases the cytotoxic activity of bortezomib in EGF-stimulated HNSCC cell lines. A combination treatment of HNSCC with bortezomib and cetuximab may allow a therapeutical regimen to be developed that is less toxic than the conventional drugs used for these tumors.

Craniofacial reconstructions with bone-anchored epithesis in head and neck cancer patients--a valid way back to self-perception and social reintegration.

BACKGROUND: Patients with advanced head and neck cancer often require radical and mutilating surgery resulting in severe impairment of their aesthetic self-perception and social life. Cosmetically satisfying results associated with high aesthetic self-perception and social reintegration are possible with bone-anchored epithesis representing a serious alternative to craniofacial reconstructive techniques using regional and free tissue transfer. PATIENTS AND METHODS: Five head and neck cancer patients treated in our Ear, Nose and Throat Department in the years 2003-2004 were evaluated after epithesial reconstruction. RESULTS: Three out of the five patients scored self-perception after epithesial reconstruction as "very good", while social integration was scored as "very good" by three and as "satisfactory" by two patients. Daily getting along was scored as "very good" by four and as satisfactory by one patient. One patient had a very good acceptance of the epithesis as a part of the body and for four patients it was satisfactory. CONCLUSION: For the first time, the high degree of satisfaction in head and neck cancer patients receiving epithesial reconstruction in the maxillofacial region is demonstrated.

Interstitial high-dose-rate-brachytherapy in advanced esthesioneuroblastoma.

Esthesioneuroblastoma is a rare neuroectodermal tumor of the nasal vault with an aggressive biological behavior that is characterized by local recurrence, atypical distant metastasis, and poor long-term prognosis. The treatment regimen consists of surgical resection, radiation therapy, and chemotherapy in various, mainly stage-dependent, combinations. We report two cases of primary metastatic and locally recurrent disease, which were treated with computed tomography-guided interstitial high-dose-rate brachytherapy in palliative and curative intent, respectively. Computed tomography-guided interstitial high-dose-rate brachytherapy should be considered as a feasible treatment option for advanced esthesioneuroblastoma.

Effect of bortezomib on EGFR expression in head and neck squamous cell carcinoma cell lines.

BACKGROUND: Overexpression of epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinoma (HNSCC) has often been correlated with poor prognosis. Recent investigations have shown that the proteasome inhibitor bortezomib exhibits a high antiproliferative and apoptotic activity in HNSCC cell lines. The present study investigated whether bortezomib has an effect on EGFR expression in different squamous cell carcinoma cell lines. MATERIALS AND METHODS: Six EGF-stimulated or non-stimulated squamous carcinoma cell lines were treated with bortezomib. Western blots were performed to determine EGFR expression. For statistical analysis, a Wilcoxon test for matched pairs (dependent samples) was performed using SPSS 13.0 software for Windows. RESULTS: Changes in EGFR expression after bortezomib treatment in EGF non-stimulated and EGF-stimulated squamous carcinoma cell lines failed to reach statistical significance in either experimental group (p > 0.05). CONCLUSION: Given the high expression of EGFR in head and neck tumors, further investigations should address the question whether the apoptotic activity of bortezomib can be enhanced by adding an anti-EGFR antibody.

Gadolinium-enhanced echo-planar T2-weighted MRI of tumors in the extracranial head and neck: feasibility study and preliminary results using a distributed-parameter tracer kinetic analysis.

PURPOSE: To examine the feasibility of first-pass dynamic contrast-enhanced (DCE) T2-weighted MRI of tumors in the extracranial head and neck by applying a distributed-parameter (DP) tracer kinetic model to quantify the perfusion parameters. MATERIALS AND METHODS: A total of 16 patients with primary malignant and benign tumors in the head and neck underwent DCE-MR studies. A spin-echo (SE) echo-planar-imaging (EPI) MR-sequence was applied for first-pass DCE-T2-weighted imaging. The data were postprocessed applying a DP tracer kinetic model that accounts for capillary-tissue exchange. Region-of-interest (ROI) analysis was performed in the tumor sites and the adjacent normal tissue. Blood flow (F), intravascular blood volume (v(1)), extravascular extracellular volume (v(2)), difference in bolus arrival time between arterial input and tissue (t(0)), intravascular mean transit time (t(1)), permeability (PS), and extraction ratio (E) maps were generated for each patient. RESULTS: All perfusion values in the tumor sites were significantly different (0.000 < or = P < or = 0.01) than those in the normal muscle tissue. The median perfusion values in the tumor tissue were: F = 150.5 mL/minute/100 g, v(1) = 11.0 mL/100 g, v(2) = 31.5 mL/100 g, t(0) = 4.5 seconds, t(1) = 8.0 seconds, PS = 96.0 mL/minute/100 g, and E = 32.5. CONCLUSION: EPI-T2-weighted DCE-MR in head and neck tumors as well as quantification of the perfusion values using DP model physiologic imaging was feasible and the promising initial results have encourages further validation studies in the future.

Cervical lymph nodes.

The lymph node staging is a very important prognostic parameter for patients with presenting with head neck cancer and is influencing the selection of the different therapeutic strategies including surgery, chemotherapy, radiotherapy or a combination of them. The accuracy of imaging techniques, such as US, MR imaging, and CT, depends on the appropriateness of radiological criteria used for diagnosing lymph node metastases. Size of nodes and evidence of necrosis are still the most important radiological criteria. However, the size shows great variability. A spherical lymph node larger than 10mm is an indicator for a malignant node, whereas an oval shape and/or a fatty hilus are more benign signs. But there are many limitations and different cut offs published in the literature, indicating that the size of a lymph node is not a reliable criteria for the assessment of lymph nodes in the head and neck region. Today new high-resolution MRI sequences and the development of specific contrast agents are offering new possibilities in the diagnostic work-up of head and neck lymph nodes. Ultrasmall superparamagnetic iron oxide particles (USPIO's) are resulting after intravenous application in a reduction of the T2 relaxation time. This is causing a signal decrease on T2-weighted MR images in benign lymph nodes after administration of USPIO's, whereas malignant lymph nodes do not show a significant signal decrease. Some clinical studies presented already very promising results. Based on the fact, that the size evaluation of lymph nodes in the head and neck has not changed during the last decade, this paper will mainly focus on MRI with new contrast agents and new techniques as diffusion weighted imaging (DWI).

A comparison of tumour perfusion assessed by deconvolution-based analysis of dynamic contrast-enhanced CT and MR imaging in patients with squamous cell carcinoma of the upper aerodigestive tract.

Our aim was to compare the perfusion [blood flow (BF)] values obtained by first-pass dynamic contrast-enhanced (DCE) T2-weighted magnetic resonance (MR) and computed tomography (CT) imaging of squamous cell carcinoma (SCC) in the upper aerodigestive tract in the same patient population. Seventeen patients with histologically proven primary SCC of the upper aerodigestive tract were prospectively evaluated. The perfusion CT studies were obtained using a 16-row multi-slice CT scanner running a commercial software package with a deconvolution-based technique; while the perfusion MR studies (1.5 T) were analysed with in-house-written MR perfusion software based also on a deconvolution technique. The mean perfusion values of SCC assessed by perfusion CT and MR imaging were 68.93 +/- 31.61 and 81.56 +/- 49.25 ml/min/100 g, respectively. The Bland-Altman graph showed a proportional error in the perfusion values measured by DCE-CT and -MR imaging; however, the degree of agreement was acceptable (95% limits of agreement: -66.1 to 40.8). Regression analysis of the perfusion values demonstrated significant correlation between the modalities: BF(MR) = 1.34 x BF(CT) - 10.93 (P < 0.0005, r (2) = 0.74). The parametric maps generated by both modalities provided insights into the tumour perfusion, while analysis of the obtained perfusion values demonstrated that both modalities may be used interchangeably in SCC in the upper aerodigestive tract.

Antiproliferative activity of bortezomib alone and in combination with cisplatin or docetaxel in head and neck squamous cell carcinoma cell lines.

PURPOSE: Proteasome inhibition has been shown to be effective in multiple myeloma and solid tumor models. In this in vitro study, we investigated the antitumor effect of bortezomib (Velcade((R))) in squamous cell carcinoma of the head and neck (SCCHN) cell lines and examined the interaction of the drug with docetaxel (TAX) and cisplatin (CDDP). METHODS: Dose escalation studies were performed with eight squamous cell carcinoma cell lines using bortezomib alone or in combination with TAX or CDDP. Growth inhibitory and proapoptotic effects were measured quantitatively using cytohistology and western blot analysis. RESULTS: Bortezomib alone showed a significant antiproliferative activity in all SCCHN cell lines (P = 0.012), and the activity was further enhanced by the addition of TAX or CDDP (P

Iron oxide particle-enhanced magnetic resonance imaging for detection of benign lymph nodes in the head and neck: how reliable are the results?

AIM: To evaluate the accuracy of ultrasmall paramagnetic iron oxide (USPIO: Sinerem)-enhanced MRI in patients with head and neck cancer and enlarged lymph nodes compared with current staging examinations using histology as a gold standard. PATIENTS AND METHODS: Seventeen patients with a histologically proven squamous cell cancer of the head and neck (SCCHN) and different N-stages underwent a non-enhanced and a USPIO-enhanced MRI examination. Signal intensity (SI) was measured in a region of interest evaluation. Pathohistological examination was used as a reference. RESULTS: On a patient basis, USPIO-enhanced MRI showed a higher specificity and diagnostic accuracy (94%) compared with non-enhanced MRI (53%). One patient showed a lymph node of 6 mm in the short axial diameter which was suggested as being metastatic in Sinerem-enhanced MRI according to the enhancement pattern of Sinerem. This patient was staged as N1 with Sinerem-enhanced MRI. The histopathological examination did not confirm the Sinerem-enhanced MRI result. CONCLUSION: The high values for the specifity and diagnostic accuracy of Sinerem- enhanced MRI justifies further investigations with this contrast agent. USPIO-enhanced MRI could be advantageous in avoiding surgical overtreatment.

Dynamic contrast-enhanced CT of head and neck tumors: perfusion measurements using a distributed-parameter tracer kinetic model. Initial results and comparison with deconvolution-based analysis.

The objective of this work was to evaluate the feasibility of a two-compartment distributed-parameter (DP) tracer kinetic model to generate functional images of several physiologic parameters from dynamic contrast-enhanced CT data obtained of patients with extracranial head and neck tumors and to compare the DP functional images to those obtained by deconvolution-based DCE-CT data analysis. We performed post-processing of DCE-CT studies, obtained from 15 patients with benign and malignant head and neck cancer. We introduced a DP model of the impulse residue function for a capillary-tissue exchange unit, which accounts for the processes of convective transport and capillary-tissue exchange. The calculated parametric maps represented blood flow (F), intravascular blood volume (v(1)), extravascular extracellular blood volume (v(2)), vascular transit time (t(1)), permeability-surface area product (PS), transfer ratios k(12) and k(21), and the fraction of extracted tracer (E). Based on the same regions of interest (ROI) analysis, we calculated the tumor blood flow (BF), blood volume (BV) and mean transit time (MTT) by using a modified deconvolution-based analysis taking into account the extravasation of the contrast agent for PS imaging. We compared the corresponding values by using Bland-Altman plot analysis. We outlined 73 ROIs including tumor sites, lymph nodes and normal tissue. The Bland-Altman plot analysis revealed that the two methods showed an accepted degree of agreement for blood flow, and, thus, can be used interchangeably for measuring this parameter. Slightly worse agreement was observed between v(1) in the DP model and BV but even here the two tracer kinetic analyses can be used interchangeably. Under consideration of whether both techniques may be used interchangeably was the case of t(1) and MTT, as well as for measurements of the PS values. The application of the proposed DP model is feasible in the clinical routine and it can be used interchangeably for measuring blood flow and vascular volume with the commercially available reference standard of the deconvolution-based approach. The lack of substantial agreement between the measurements of vascular transit time and permeability-surface area product may be attributed to the different tracer kinetic principles employed by both models and the detailed capillary tissue exchange physiological modeling of the DP technique.

Primary B cell lymphoma of the sphenoid sinus: CT and MRI characteristics with correlation to perfusion and spectroscopic imaging features.

Primary non-Hodgkin lymphoma (NHL) of the paranasal sinuses is a rare neoplasm that cannot be easily diagnosed and differentiated as its clinical, histological, and imaging features are similar to those of other inflammatory and tumorous diseases in their early stages. We evaluated the morphological and functional imaging characteristics of primary NHL of the sphenoid sinus using CT and MR imaging. Morphological CT and MR imaging as well as perfusion CT imaging and proton MR spectroscopy (PRESS technique, TE = 135) was performed in three patients with the histological diagnosis of highly malignant primary B cell lymphoma of the sphenoid sinus. In all patients an inhomogeneous contrast agent enhancement as well as bony erosion of the sphenoid sinus was identified in CT and MR sections. In one patient an infiltration of the adjacent dura was present. The mean blood flow of the lymphomas was 135 ml/min per 100 g tissue, the mean blood volume was 8.06 ml/min, while the mean transit time and the mean permeability surface area product values were 5.11 s and 26.53 ml/min per 100 g, respectively. The mean choline to creatine ratio in the proton MR spectroscopy was 5.7. Cross-sectional imaging findings are not sufficient to establish the diagnosis of a primary NHL in the sphenoid sinus. Physiologic imaging offers valuable information that may be characteristic of the tumor. Future studies may lead to a safe differentiation of the lymphomas from other pathologic entities based on the combination of morphological and functional imaging.