Clinical utility of single-shot echo-planar diffusion-weighted imaging using L1-regularized iterative sensitivity encoding in prostate MRI

We investigated the ability of echo-planar imaging with L1-regularized iterative sensitivity encoding-based diffusion-weighted imaging (DWI) to improve the image quality and reduce the scanning time in prostate magnetic resonance imaging. We retrospectively analyzed 109 cases of prostate magnetic resonance imaging. We compared variables in the quantitative and qualitative assessments among 3 imaging groups: conventional parallel imaging-based DWI (PI-DWI) with an acquisition time of 3 minutes 15 seconds; echo-planar imaging with L1-regularized iterative sensitivity encoding-based DWI (L1-DWI) with a normal acquisition time (L1-DWINEX12) of 3 minutes 15 seconds; and L1-DWI with a half acquisition time (L1-DWINEX6) of 1 minute 45 seconds. As a quantitative assessment, the signal-to-noise ratio (SNR) of DWI (SNR-DWI), the contrast-to-noise ratio (CNR) of DWI (CNR-DWI), and the CNR of apparent diffusion coefficient were measured. As a qualitative assessment, the image quality and visual detectability of prostate carcinoma were evaluated. In the quantitative analysis, L1-DWINEX12 showed significantly higher SNR-DWI than PI-DWI (P = .0058) and L1-DWINEX6 (P < .0001). In the qualitative analysis, the image quality score for L1-DWINEX12 was significantly higher than those of PI-DWI and L1-DWINEX6. A non-inferiority assessment demonstrated that L1-DWINEX6 was non-inferior to PI-DWI in terms of both quantitative CNR-DWI and qualitative grading of image quality with a <20% inferior margin. L1-DWI successfully demonstrated a reduced scanning time while maintaining good image quality.

A case of breast angiosarcoma clearly delineated by contrast-enhanced ultrasonography

We present a case of breast angiosarcoma. Although B-mode ultrasonography did not indicate a tumor, contrast-enhanced ultrasonography (CEUS) was successfully delineated it. CEUS helped identify the tumor and its extent.

Distribution of human papilloma virus genotypes and treatment outcomes in definitive radiotherapy for cervical cancer

Most oncogenic human papilloma virus (HPV) genotypes stratify into two species, α-7 HPV and α-9 HPV. There are several studies that evaluate the relationship between HPV species and treatment outcomes and reports that HPV species is prognostic. The HPV genotyping was conducted using biopsy specimens which had been stored in these studies. We conducted the study using the HPV test performed by cytology specimens which is less invasive and more useful in clinical settings. This study enrolled 46 patients who received HPV genotyping before the definitive radiotherapy. The results of the HPV genotyping were classified into HPVα-7, HPVα-9 and negatives. Of the 46 patients, 10 were positive for HPVα-7, 21 positive for HPVα-9 and 15 were negative. The median follow-up period was 38 months (range 4-142). The HPVα-7, HPVα-9 and negative groups showed the 3-year overall survival (OS; 59.3%, 80.4% and 72.2% [P = 0.25]); local control (LC; 67.5%, 81% and 80% [P = 0.78]); pelvic control (PC) (50%, 81% and 72.7% [P = 0.032]); pelvic lymph node (PLN) control (78.7%, 95% and 92.3% [P = 0.012]); distant metastasis free (DMF) survival (50%, 75.4% and 42.8% [P = 0.098]); and progression free survival (PFS) rate of patients (30%, 66.7% and 38.9% [P = 0.085]), respectively. Patients with HPVα-7 showed statistically significant poorer PC than the HPVα-9 group, in multivariate analysis. This result is consistent with previous studies for HPV positive patients. The HPV negativity rate was higher in this study than in other studies and further work on this may be needed for clinical use.

Patterns and predictors of site-specific recurrence in cervical cancer after radical hysterectomy

AIM

This study examines patterns and predictors of site-specific recurrence to explore the causes of local recurrence of cervical cancer.

METHODS

Radical hysterectomy was performed in 121 patients (stage IB-IIB). Nerve-sparing was performed whenever possible. The first recurrence in local, regional, and distant areas was examined. We investigated the possibility of nerve involvement in local recurrence, focusing on paravaginal tissues containing the pelvic plexus. We provide Supporting Information on local recurrence in the paravaginal area.

RESULTS

Local recurrence was an independent event from regional or distant recurrence. Local recurrence was seen only in high-risk patients, while regional and distant recurrences were not or less related to the risk category. The independent risk factors by logistic regression for local, regional, and distant recurrence were parametrial invasion, vaginal invasion, and lymph node metastasis, respectively. Local recurrence showed a comparable or more significant negative impact on survival than distant recurrence. Among seven patients with local recurrences, five had a recurrence in the paravagina. The rate of paravaginal recurrence was one in 76 early-stage and four in 45 locally advanced diseases. Four sites of paravaginal recurrence occurred on the nerve-sparing side and two on the non-nerve-sparing side. Supporting Information demonstrated histological evidence of perineural spread into the pelvic plexus and perineural invasion of the primary tumor.

CONCLUSIONS

A high percentage of local recurrences are in paravaginal tissue containing the pelvic plexus. The causal association of nerve-sparing surgery and perineural invasion with local recurrence needs to be investigated in large prospective studies.

Imaging findings of ovarian metastasis of primary renal cell carcinoma: A case report and literature review

A 62-year-old woman presented with a tumor in the right kidney. A right partial nephrectomy was performed, and the tumor was diagnosed as clear cell renal cell carcinoma (RCC) on histopathological examination. A right ovarian tumor was detected on follow-up computed tomography (CT) 5 years after partial nephrectomy and pathology proved RCC metastasis. RCC rarely metastasizes to the ovaries. There is limited information on the radiological features of ovarian metastasis in RCC. In this case report, we presented the CT and magnetic resonance images of ovarian metastasis of RCC. In addition, we also presented a literature review with special emphasis on the imaging features of ovarian metastasis of RCC.

A treatment planning study of urethra-sparing intensity-modulated proton therapy for localized prostate cancer

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US-IMPT can potentially reduce the risk of genitourinary toxicities.

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The urethral NTCP value in US-IMPT is significantly lower than in the clinical plan.

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TCP for CTV did not differ significantly between the clinical and US-IMPT plans.

Background and Purpose

Urethra-sparing radiation therapy for localized prostate cancer can reduce the risk of radiation-induced genitourinary toxicity by intentionally underdosing the periurethral transitional zone. We aimed to compare the clinical impact of a urethra-sparing intensity-modulated proton therapy (US-IMPT) plan with that of conventional clinical plans without urethral dose reduction.

Materials and Methods

This study included 13 patients who had undergone proton beam therapy. The prescribed dose was 63 GyE in 21 fractions for 99% of the clinical target volume. To compare the clinical impact of the US-IMPT plan with that of the conventional clinical plan, tumor control probability (TCP) and normal tissue complication probability (NTCP) were calculated with a generalized equivalent uniform dose-based Lyman–Kutcher model using dose volume histograms. The endpoints of these model parameters for the rectum, bladder, and urethra were fistula, contraction, and urethral stricture, respectively.

Results

The mean NTCP value for the urethra in US-IMPT was significantly lower than that in the conventional clinical plan (0.6% vs. 1.2%, p < 0.05). There were no statistically significant differences between the conventional and US-IMPT plans regarding the mean minimum dose for the urethra with a 3-mm margin, TCP value, and NTCP value for the rectum and bladder. Additionally, the target dose coverage of all plans in the robustness analysis was within the clinically acceptable range.

Conclusions

Compared with the conventional clinically applied plans, US-IMPT plans have potential clinical advantages and may reduce the risk of genitourinary toxicities, while maintaining the same TCP and NTCP in the rectum and bladder.

Radiological tumor classification across imaging modality and histology

Radiomics refers to the high-throughput extraction of quantitative features from radiological scans and is widely used to search for imaging biomarkers for prediction of clinical outcomes. Current radiomic signatures suffer from limited reproducibility and generalizability, because most features are dependent on imaging modality and tumor histology, making them sensitive to variations in scan protocol. Here, we propose novel radiological features that are specially designed to ensure compatibility across diverse tissues and imaging contrast. These features provide systematic characterization of tumor morphology and spatial heterogeneity. In an international multi-institution study of 1,682 patients, we discover and validate four unifying imaging subtypes across three malignancies and two major imaging modalities. These tumor subtypes demonstrate distinct molecular characteristics and prognoses after conventional therapies. In advanced lung cancer treated with immunotherapy, one subtype is associated with improved survival and increased tumor-infiltrating lymphocytes compared with the others. Deep learning enables automatic tumor segmentation and reproducible subtype identification, which can facilitate practical implementation. The unifying radiological tumor classification may inform prognosis and treatment response for precision medicine.

Visualizing the urethra by magnetic resonance imaging without usage of a catheter for radiotherapy of prostate cancer

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Post urination MRI is useful for urethra-sparing radiotherapy treatment planning.

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This prospective clinical trial included 11 prostate cancer patients.

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Post urination MRI is the identification method of prostatic urinary tract in non-invasive manner.

The urethra position may shift due to the presence/absence of the catheter. Our proposed post-urination-magnetic resonance imaging (PU-MRI) technique is possible to identify the urethra without catheter. We aimed to verify the inter-operator difference in contouring the urethra by PU-MRI. The mean values of the evaluation indices of dice similarity coefficient, mean slice-wise Hausdorff distance, and center coordinates were 0.93, 0.17 mm, and 0.36 mm for computed tomography, and 0.75, 0.44 mm, and 1.00 mm for PU-MRI. Therefore, PU-MRI might be useful for identifying the prostatic urinary tract without using a urethral catheter.

Clinical trial registration: Hokkaido University Hospital for Clinical Research (018-0221).

Neuroendocrine carcinoma of uterine cervix findings shown by MRI for staging and survival analysis - Japan multicenter study

Objectives: To investigate neuroendocrine carcinoma (NEC) of the uterine cervix cases for MRI features and staging, as well as pathological correlations and survival.

Results: FIGO was I in 42, II in 14, III in 1, and IV in 5 patients. T2-weighted MRI showed homogeneous slightly high signal intensity and obvious restricted diffusion (ADC map, low intensity; DWI, high intensity) throughout the tumor in most cases, and mild enhancement in two-thirds. In 50 patients who underwent a radical hysterectomy and lymphadenectomy without neoadjuvant chemotherapy (NAC), intrapelvic T staging by MRI overall accuracy was 88.0% with reference to pathology staging, while patient-based sensitivity, specificity, and accuracy for metastatic pelvic lymph node detection was 38.5%, 100%, and 83.3%, respectively. During a mean follow-up period of 45.6 months (range 4.3–151.0 months), 28 patients (45.2%) experienced recurrence and 24 (38.7%) died. Three-year progression-free and overall survival rates for FIGO I, II, III, and IV were 64.3% and 80.9%, 50% and 64.3%, 0% and 0%, and 0% and 0%, respectively.

Materials and Methods: Sixty-two patients with histologically surgery-proven uterine cervical NEC were enrolled. Twelve received NAC. Clinical data, pathological findings, and pretreatment pelvic MRI findings were retrospectively reviewed. Thirty-two tumors were pure NEC and 30 mixed with other histotypes. The NECs were small cell type (41), large cell type (18), or a mixture of both (3).

Conclusions: Homogeneous lesion texture with obvious restricted diffusion throughout the tumor are features suggestive of cervical NEC. Our findings show that MRI is reliable for T staging of cervical NEC.

Characteristics of MR Imaging for Staging and Survival Analysis of Neuroendocrine Carcinoma of the Endometrium: A Multicenter Study in Japan

Purpose:

This study aimed to examine MRI features and staging of neuroendocrine carcinoma (NEC) of the endometrium and evaluate survival.

Methods:

Clinical data, pathological, and preoperative pelvic MRI findings in 22 patients with histologically surgery-proven endometrial NEC were retrospectively reviewed. Tumors were pure NEC (n = 10) or mixed histotype (n = 12), with 13 large and nine small cell type.

Results:

International Federation of Gynecology and Obstetrics (FIGO) staging was I, II, III, and IV in 6, 2, 12, and 2 patients, respectively. In 13 (76.4%) of 17 patients with pathological deep myometrial invasion, MRI showed abnormal diffusely infiltrative high T₂ signal intensity throughout the myometrium with loss of normal uterine architecture. All tumors had restricted diffusion (apparent diffusion coefficient map low signal intensity, diffusion weighted imaging high signal intensity). Accuracy of T staging by MRI for all cases was 81.8%, with reference to pathology staging, while patient-based sensitivity, specificity, and accuracy for detecting metastatic pelvic lymph nodes was 60.0%, 100%, and 77.8%, respectively. Two intrapelvic peritoneal dissemination cases were detected by MRI. During follow-up (mean 30.4, range 3.3–138.4 months), 16 patients (72.7%) experienced recurrence and 12 (54.5%) died of disease. Two-year disease-free and overall survival rates for FIGO I, II, III, and IV were 66.7% and 83.3%, 50% and 100%, 10% and 33.3%, and 0% and 0%, respectively.

Conclusion:

Abnormal diffusely infiltrative high T₂ signal intensity throughout the myometrium with normal uterine architecture loss and obvious restricted diffusion throughout the tumor are suggestive features of endometrial NEC. Pelvic MRI is reliable for intrapelvic staging of affected patients.

Improvement of image quality on low-dose dynamic myocardial perfusion computed tomography with a novel 4-dimensional similarity filter

The aim of this study was to evaluate the effect of a novel 4-dimensional similarity filter (4DSF) on quantitative and qualitative parameters of low-dose dynamic myocardial computed tomography perfusion (CTP) images.In this retrospective study, medical records of 32 patients with suspected or known coronary artery disease who underwent dynamic myocardial CTP at 80 kV were included. The 4DSF reduces noise by averaging voxels that have similar dynamic behavior after adaptive iterative dose reduction 3D (AIDR3D) and deformable image registration were applied. Qualitative (artefact, contour sharpness, and myocardial homogeneity [1 = poor; 2 = intermediate; 3 = good]) and quantitative measurement (standard deviation [SD] and signal-to-noise ratio [SNR]) were compared between the 4DSF and AIDR3D. Contrast-to-noise ratio (CNR) between ischemic and normal remote myocardium was also assessed using myocardial perfusion magnetic resonance imaging as the reference standard in seven patients.The 4DSF was successfully applied to all the images. Improvement in subjective image quality yielded by 4DSF was higher than that yielded by AIDR3D (homogeneity, 1.0 [3 vs 2]; artefact, 1.5 [3 vs 1.5]; P < .001) in all patients. The 4DSF significantly decreased the SD by 59% (AIDR3D vs 4DSF: 33.5 ± 0.4 vs 13.8 ± 0.4, P < .001), increased the SNR by 134% (AIDR3D vs 4DSF: 4.4 ± 0.2 vs 10.3 ± 0.2, P < .001), and increased the CNR by 131% (AIDR3D vs 4DSF: 1.6 ± 0.2 vs 3.7 ± 0.2, P < .001).The 4DSF improved the qualitative and quantitative parameters of low-dose dynamic myocardial CTP images.

Assessment of Coronary Flow Velocity Reserve in the Left Main Trunk Using Phase-contrast MR Imaging at 3T: Comparison with 15O-labeled Water Positron Emission Tomography

Purpose:

The aim of this study was to verify coronary flow velocity reserve (CFVR) on the left main trunk (LMT) in comparison with myocardial flow reserve (MFR) by ¹⁵O-labeled water positron emission tomography (PET) (MFR-PET) in both the healthy adults and the patients with coronary artery disease (CAD), and to evaluate the feasibility of CFVR to detect CAD.

Methods:

Eighteen healthy adults and 13 patients with CAD were evaluated. CFVR in LMT was estimated by 3T magnetic resonance imaging (MRI) with phase contrast technique. MFR-PET in the LMT territory including anterior descending artery and circumflex artery was calculated as the ratio of myocardial blood flow (MBF)-PET at stress to MBF-PET at rest.

Results:

There was a significant positive relationship between CFVR and MFR-PET (R = 0.45, P < 0.0001). Inter-observer calculations of CFVR showed good correlation (R² = 0.93, P < 0.0001). The CFVR in patients with CAD was significantly lower than that in healthy adults (1.90 ± 0.61 vs. 2.77 ± 1.03, respectively, P = 0.01), which were similar to the results of MFR-PET (2.23 ± 0.84 vs. 3.96 ± 1.04, respectively, P < 0.0001). For the detection of patients with CAD, the area under the curve was 0.78 (P = 0.01). The sensitivity was 0.77 and specificity was 0.72 when a cut-off of 2.15 was used.

Conclusion:

CFVR by 3T was validated with MFR-PET. CFVR could detect the patients with CAD. This method is a simple and reliable index without radiation or contrast material.

Predicting metastasis in clinically negative axillary lymph nodes with minimum apparent diffusion coefficient value in luminal A-like breast cancer

BACKGROUND

We investigated the usefulness of the minimum ADC value of primary breast lesions for predicting axillary lymph node (LN) status in luminal A-like breast cancers with clinically negative nodes in comparison with the mean ADC.

METHODS

Forty-four luminal A-like breast cancers without axillary LN metastasis at preoperative clinical evaluation, surgically resected with sentinel LN biopsy, were retrospectively studied. Mean and minimum ADC values of each lesion were measured and statistically compared between LN positive (n = 12) and LN negative (n = 32) groups. An ROC curve was drawn to determine the best cutoff value to differentiate LN status. Correlations between mean and minimum ADC values and the number of metastatic axillary LNs were investigated.

RESULTS

Mean and minimum ADC values of breast lesions with positive LN were significantly lower than those with negative LN (mean 839.9 ± 110.9 vs. 1022.2 ± 250.0 × 10^- 6 mm²/s, p = 0.027, minimum 696.7 ± 128.0 vs. 925.0 ± 257.6 × 10^- 6 mm²/s, p = 0.004). The sensitivity and NPV using the best cutoff value from ROC using both mean and minimum ADC were 100%. AUC of the minimum ADC (0.784) was higher than that of the mean ADC (0.719). Statistically significant negative correlations were observed between both mean and minimum ADCs and number of positive LNs, with stronger correlation to minimum ADC than mean ADC.

CONCLUSIONS

The minimum ADC value of primary breast lesions predicts axillary LN metastasis in luminal A-like breast cancer with clinically negative nodes, with high sensitivity and high NPV.

Heterogeneity of longitudinal and circumferential contraction in relation to late gadolinium enhancement in hypertrophic cardiomyopathy patients with preserved left ventricular ejection fraction

PURPOSE

To evaluate heterogeneity of myocardial contraction in relation to extensive late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM) patients with preserved left ventricular ejection fraction, using fast strain-encoded magnetic resonance imaging.

MATERIALS AND METHODS

Twenty-two HCM patients and 24 age-matched control subjects were included in this retrospective study. The regional and global peak values of longitudinal and circumferential strain (LS_regional, LS_global, CS_regional, CS_global), and their regional heterogeneities were evaluated using coefficients of variation (LS_CoV, CS_CoV) in relation to LGE. Receiver operating characteristic curve analysis was performed to identify patients with a total left ventricular myocardial LGE ≥ 15%.

RESULTS

LS_global in HCM patients was significantly decreased compared to that in controls (- 14.4 ± 2.4% vs - 17.2 ± 2.0%; p = 0.0004), while CS_global was not (p = 1.0). Negative LGE segments demonstrated decreased LS_regional in HCM patients compared to in controls (p < 0.0001), while CS_regional was not decreased. CS_CoV demonstrated the largest area under the curve (AUC) (0.91), with high sensitivity (83%) and specificity (94%) for detection of HCM patients with extensive LGE, while the AUC of LS_CoV was low (0.49).

CONCLUSION

The heterogeneity in CS_regional has a high diagnostic value for detection of HCM patients with extensive LGE.

Sudden maternal hypoxemia during elective cesarean section in a woman with placenta previa

There have been no reports regarding imaging‐documented bronchospasm in patients with amniotic fluid embolism (AFE). In a woman with scheduled cesarean section for placenta previa, transient bronchospasm and pulmonary hypertension were documented explaining a sudden drop in SpO₂. Mild AFE was the most likely diagnosis in this patient.

Breast cancer detected as an incidental finding on 99mTc-MIBI scintigraphy

We report a case of breast cancer detected as an incidental finding on ^99mTc-MIBI scintigraphy. ^99mTc-MIBI scintigraphy is usually used to evaluate cardiac perfusion or to detect ectopic parathyroid adenomas; however, it is also known to sensitively detect breast cancer. Accordingly, a few reports have described the incidental detection of breast cancer by ^99mTc-MIBI scintigraphy performed to detect parathyroid adenoma. Our present case underscores the importance of attending to any incidental findings when searching for parathyroid adenomas using ^99mTc-MIBI scintigraphy.

Identifying relations between imaging phenotypes and molecular subtypes of breast cancer: Model discovery and external validation

PURPOSE

To determine whether dynamic contrast enhancement magnetic resonance imaging (DCE-MRI) characteristics of the breast tumor and background parenchyma can distinguish molecular subtypes (ie, luminal A/B or basal) of breast cancer.

MATERIALS AND METHODS

In all, 84 patients from one institution and 126 patients from The Cancer Genome Atlas (TCGA) were used for discovery and external validation, respectively. Thirty-five quantitative image features were extracted from DCE-MRI (1.5 or 3T) including morphology, texture, and volumetric features, which capture both tumor and background parenchymal enhancement (BPE) characteristics. Multiple testing was corrected using the Benjamini-Hochberg method to control the false-discovery rate (FDR). Sparse logistic regression models were built using the discovery cohort to distinguish each of the three studied molecular subtypes versus the rest, and the models were evaluated in the validation cohort.

RESULTS

On univariate analysis in discovery and validation cohorts, two features characterizing tumor and two characterizing BPE were statistically significant in separating luminal A versus nonluminal A cancers; two features characterizing tumor were statistically significant for separating luminal B; one feature characterizing tumor and one characterizing BPE reached statistical significance for distinguishing basal (Wilcoxon P < 0.05, FDR < 0.25). In discovery and validation cohorts, multivariate logistic regression models achieved an area under the receiver operator characteristic curve (AUC) of 0.71 and 0.73 for luminal A cancer, 0.67 and 0.69 for luminal B cancer, and 0.66 and 0.79 for basal cancer, respectively.

CONCLUSION

DCE-MRI characteristics of breast cancer and BPE may potentially be used to distinguish among molecular subtypes of breast cancer.

LEVEL OF EVIDENCE

3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017;46:1017-1027.

Comparison between borderline ovarian tumors and carcinomas using semi-automated histogram analysis of diffusion-weighted imaging: focusing on solid components

PURPOSE

This study aimed to evaluate whether histogram analysis of the apparent diffusion coefficient (ADC) of a solid tumor component could distinguish borderline ovarian tumors from ovarian carcinoma.

MATERIALS AND METHODS

Sixteen pathologically proven borderline tumors and 21 carcinomas were retrospectively examined. Magnetic resonance (1.5-T) image data sets were coregistered, and the solid components of each tumor were semiautomatically segmented. ADC histograms of the solid components were extracted; modes, minimums, means, and 10th, 25th, 50th, 75th, and 90th percentiles of the histograms were compared between the two tumor types, and receiver-operating characteristic (ROC) analysis was performed.

RESULTS

The mode, minimum, mean, 10th, 25th, 50th, and 75th percentile ADC values of solid components of borderline tumors were significantly larger than those of carcinomas. Among these, the 10th percentile values had the lowest p value (p = 0.0003). At ROC analysis, the area under the curve (AUC) in the 10th percentile was the greatest (0.854), and the best cutoff value in the 10th percentile provided the highest specificity (93.8 %).

CONCLUSIONS

ADC histograms of solid tumor components facilitated the distinction between borderline ovarian tumors and carcinoma. The 10th percentile ADC values had the best diagnostic performance.

Identifying Triple-Negative Breast Cancer Using Background Parenchymal Enhancement Heterogeneity on Dynamic Contrast-Enhanced MRI: A Pilot Radiomics Study

OBJECTIVES

To determine the added discriminative value of detailed quantitative characterization of background parenchymal enhancement in addition to the tumor itself on dynamic contrast-enhanced (DCE) MRI at 3.0 Tesla in identifying "triple-negative" breast cancers.

MATERIALS AND METHODS

In this Institutional Review Board-approved retrospective study, DCE-MRI of 84 women presenting 88 invasive carcinomas were evaluated by a radiologist and analyzed using quantitative computer-aided techniques. Each tumor and its surrounding parenchyma were segmented semi-automatically in 3-D. A total of 85 imaging features were extracted from the two regions, including morphologic, densitometric, and statistical texture measures of enhancement. A small subset of optimal features was selected using an efficient sequential forward floating search algorithm. To distinguish triple-negative cancers from other subtypes, we built predictive models based on support vector machines. Their classification performance was assessed with the area under receiver operating characteristic curve (AUC) using cross-validation.

RESULTS

Imaging features based on the tumor region achieved an AUC of 0.782 in differentiating triple-negative cancers from others, in line with the current state of the art. When background parenchymal enhancement features were included, the AUC increased significantly to 0.878 (p<0.01). Similar improvements were seen in nearly all subtype classification tasks undertaken. Notably, amongst the most discriminating features for predicting triple-negative cancers were textures of background parenchymal enhancement.

CONCLUSIONS

Considering the tumor as well as its surrounding parenchyma on DCE-MRI for radiomic image phenotyping provides useful information for identifying triple-negative breast cancers. Heterogeneity of background parenchymal enhancement, characterized by quantitative texture features on DCE-MRI, adds value to such differentiation models as they are strongly associated with the triple-negative subtype. Prospective validation studies are warranted to confirm these findings and determine potential implications.

Differences in morphological features and minimum apparent diffusion coefficient values among breast cancer subtypes using 3-tesla MRI

PURPOSE

To compare the morphology and minimum apparent diffusion coefficient (ADC) values among breast cancer subtypes.

METHODS

Ninety-three patients, who underwent breast MRI and collectively had 98 pathologically proven invasive carcinomas, were enrolled. Morphology was evaluated according to BIRADS-MRI. Minimum ADC was measured. Morphology and minimum ADC were compared among subtypes. Multivariate logistic regression analyses were used to identify the characteristics associated with different subtypes.

RESULTS

Oval/round shape was significantly associated with triple-negative (TN) cancer (TN vs. non-TN: 90.9% vs. 45.2%; p=0.0123). Rim enhancement was significantly less frequent in Luminal A (Luminal A vs. non-Luminal A: 34.2% vs. 76.1%; p=0.0003). The minimum ADC of Luminal A was significantly higher than that of Luminal B (HER2-negative) (834 vs. 748×10(-6)mm(2)/s; p<0.025). The minimum ADC of the TN-special type was significantly higher than that of TN-ductal (997 vs. 702×10(-6)mm(2)/s; p<0.025). On the multivariate analysis comparing the characteristics associated with Luminal A vs. Luminal B (HER2-negative), the internal enhancement characteristics of the mass and minimum ADC were significant factors.

CONCLUSION

Morphology and minimum ADC would be useful in distinguishing breast cancer subtypes.

Five-point Likert scaling on MRI predicts clinically significant prostate carcinoma

Background

To clarify the relationship between the probability of prostate cancer scaled using a 5-point Likert system and the biological characteristics of corresponding tumor foci.

Methods

The present study involved 44 patients undergoing 3.0-Tesla multiparametric MRI before laparoscopic radical prostatectomy. Tracing based on pathological and MRI findings was performed. The relationship between the probability of cancer scaled using the 5-point Likert system and the biological characteristics of corresponding tumor foci was evaluated.

Results

A total of 102 tumor foci were identified histologically from the 44 specimens. Of the 102 tumors, 55 were assigned a score based on MRI findings (score 1: n = 3; score 2: n = 3; score 3: n = 16; score 4: n = 11 score 5: n = 22), while 47 were not pointed out on MRI. The tracing study revealed that the proportion of >0.5 cm³ tumors increased according to the upgrade of Likert scores (score 1 or 2: 33 %; score 3: 68.8 %; score 4 or 5: 90.9 %, χ² test, p < 0.0001). The proportion with a Gleason score >7 also increased from scale 2 to scale 5 (scale 2: 0 %; scale 3: 56.3 %; scale 4: 72.7 %; 5: 90.9 %, χ² test, p = 0.0001). On using score 3 or higher as the threshold of cancer detection on MRI, the detection rate markedly improved if the tumor volume exceeded 0.5 cm³ (<0.2 cm³: 10.3 %; 0.2-0.5 cm³: 25 %; 0.5-1.0 cm³: 66.7 %; 1.0 < cm³: 92.1 %).

Conclusions

Each Likert scale favobably reflected the corresponding tumor’s volume and Gleason score. Our observations show that “score 3 or higher” could be a useful threshold to predict clinically significant carcinoma when considering treatment options.

Dysgammaglobulinemia Associated With Glu349del, a Hypomorphic XIAP Mutation

BACKGROUND

X-linked lymphoproliferative syndrome type 2 is a rare hereditary immunodeficiency caused by mutations in the XIAP gene. This immunodeficiency frequently results in hemophagocytic lymphohistiocytosis, although hypogammaglobulinemia and dysgammaglobulinemia are also common.

OBJECTIVE

We identified 17 patients from 12 Japanese families with mutations in XIAP. The Glu349del mutation was observed in 3 patients, each from a different family. Interestingly, these patients exhibited dysgammaglobulinemia but not hemophagocytic lymphohistiocytosis. We conducted an immunological study of patients carrying Glu349del and other mutations to elucidate the pathogenic mechanisms of dysgammaglobulinemia in patients with mutations in the XIAP gene.

PATIENTS AND METHODS

We performed an immunological study of 2 patients carrying the Glu349del mutation and 8 patients with other mutations.

RESULTS

Flow cytometry showed that the percentage of memory B cells in patients with a mutation in XIAP was lower than that observed in the healthy controls. The patients with the Glu349del mutation had a lower percentage of memory B cells than those with other mutations. Ig production was reduced in patients with the Glu349del mutation. Increased susceptibility to apoptosis was observed in the patients with other mutations. Susceptibility to apoptosis was normal in patients with Glu349del. Microarray analysis indicated that expression of Ig-related genes was reduced in patients with the Glu349del mutation and that the pattern was different from that observed in the healthy controls or patients with other mutations in XIAP.

CONCLUSIONS

Patients carrying the Glu349del mutation in the XIAP gene may have a clinically and immunologically distinct phenotype from patients with other XIAP mutations. The Glu349del mutation may be associated with dysgammaglobulinemia.

Relationship between Sympathetic Skin Responses and Auditory Hypersensitivity to Different Auditory Stimuli

[Purpose] Auditory hypersensitivity has been widely reported in patients with autism spectrum disorders. However, the neurological background of auditory hypersensitivity is currently not clear. The present study examined the relationship between sympathetic nervous system responses and auditory hypersensitivity induced by different types of auditory stimuli. [Methods] We exposed 20 healthy young adults to six different types of auditory stimuli. The amounts of palmar sweating resulting from the auditory stimuli were compared between groups with (hypersensitive) and without (non-hypersensitive) auditory hypersensitivity. [Results] Although no group × type of stimulus × first stimulus interaction was observed for the extent of reaction, significant type of stimulus × first stimulus interaction was noted for the extent of reaction. For an 80 dB-6,000 Hz stimulus, the trends for palmar sweating differed between the groups. For the first stimulus, the variance became larger in the hypersensitive group than in the non-hypersensitive group. [Conclusion] Subjects who regularly felt excessive reactions to auditory stimuli tended to have excessive sympathetic responses to repeated loud noises compared with subjects who did not feel excessive reactions. People with auditory hypersensitivity may be classified into several subtypes depending on their reaction patterns to auditory stimuli.

Hand-assisted laparoscopic splenectomy for sclerosing angiomatoid nodular transformation of the spleen complicated by chronic disseminated intravascular coagulation: a case report

A 36-year-old man who presented with a nosebleed and anemia was referred to our hospital. Laboratory test results showed platelet depletion, decreased levels of fibrinogen, and increased fibrinogen degeneration products. CT showed a 13-cm splenic tumor. T2 -weighted MRI revealed a high-intensity mass. We preoperatively diagnosed splenic hemangioma with chronic disseminated intravascular coagulation and scheduled an operation to relieve the disseminated intravascular coagulation. We also performed hand-assisted laparoscopic splenectomy to ensure easy handling of the splenomegaly. The resected specimen microscopically consisted of hemorrhages and hemangiomatous lesions, and multiple angiomatoid nodules were scattered and separated by fibrocollagenous stroma with inflammatory cells. Three types of vessels (capillaries, sinusoids and small veins) were contained in the angiomatoid nodules, and the pathological diagnosis was sclerosing angiomatoid nodular transformation. The results of this case suggest that we should consider sclerosing angiomatoid nodular transformation in the differential diagnosis of patients with splenic tumors, as sclerosing angiomatoid nodular transformation with hemangiomatous features may cause coagulation disorders for which splenectomy should be performed.

Earlier and better high-resolution single breast imaging during bilateral breast dynamic scans at 3-T MRI: comparison with post dynamic high-resolution imaging

BACKGROUND

Breast MRI protocols have been improved by using a combination of dynamic scans for bilateral breasts and high-resolution imaging for a single breast which can be obtained during dynamic scans by recent technological advances. The purpose of this study was to compare high-resolution imaging during dynamic scans (HR-intra) with high-resolution imaging obtained post dynamic scans (HR-post).

METHODS

Fifty-five women with pathologically proven breast cancer who underwent breast dynamic scans at 3-T MRI from February to September 2009 were enrolled in this study. Tumoral contrasts to the background breast tissue were compared by three radiologists independently in a blinded fashion. Results of visual assessment were categorized into three groups as follows: HR-intra being better (IB), equal (E), and HR-post being better (PB). The contrast to noise ratio (CNR) of the tumor and the signal to noise ratio of the normal breast gland (SNR) were compared between HR-intra and HR-post.

RESULTS

Two patients were excluded because of poor MR imaging quality. Three radiologists separately categorized 64.2, 79.2, and 77.4 % of lesions as IB. The CNR of the tumor of HR-intra (mean ± SD = 6.9 ± 4.0) was significantly higher than that of HR-post (6.0 ± 3.7, p < 0.0001). The SNR of the normal breast gland of HR-intra (9.5 ± 1.7) was significantly lower than that of HR-post (10.0 ± 1.9, p < 0.0001).

CONCLUSION

HR-intra during dynamic MRI provided earlier and better tumor to normal breast gland contrast than HR-post.

Observation of the (Λ)(7)He hypernucleus by the (e, e'K+) reaction

An experiment with a newly developed high-resolution kaon spectrometer and a scattered electron spectrometer with a novel configuration was performed in Hall C at Jefferson Lab. The ground state of a neutron-rich hypernucleus, (Λ)(7)He, was observed for the first time with the (e, e'K+) reaction with an energy resolution of ~0.6 MeV. This resolution is the best reported to date for hypernuclear reaction spectroscopy. The (Λ)(7)He binding energy supplies the last missing information of the A = 7, T = 1 hypernuclear isotriplet, providing a new input for the charge symmetry breaking effect of the ΛN potential.

The strain-encoded (SENC) MR imaging for detection of global right ventricular dysfunction in pulmonary hypertension

The aim of this study was to explore whether the regional peak longitudinal (LS) and circumferential strains (CS) at the right ventricular (RV) free wall could be used to identify global RV dysfunction in relation to RV ejection fraction (RVEF) and plasma concentration of brain natriuretic peptide (BNP) in pulmonary hypertension (PH). A total of 37 consecutive patients diagnosed with PH and 13 healthy control subjects were included. Fast strain encoded and routine cine MRI was performed. The LS and CS at three RV levels were quantified and their relations with RVEF and BNP were investigated. Receiver operating characteristic (ROC) analysis was employed to assess the diagnostic utility of strain encoded MRI for the detection of low RVEF. Significant correlations with LS were observed for RVEF and BNP. Compared to CS, LS showed better correlation with RVEF. The mid-ventricular level of RV was the most sensitive site for evaluation of RV dysfunction. According to our ROC analysis, LS showed higher sensitivity and specificity to detect low RVEF. Compared to CS, LS showed stronger correlations with RVEF and BNP and could be a good detector of RV dysfunction in PH.

Usefulness of portography and contrast-enhanced computed tomography to predict the embolized area in percutaneous transhepatic portal vein embolization with absolute ethanol under temporary balloon occlusion

PURPOSE

To assess the usefulness of portography and contrast-enhanced computed tomography (CECT) for predicting the embolized area after the first injection of absolute ethanol (AE) in right portal vein embolization (RPVE).

MATERIALS AND METHODS

Portograms were retrospectively reviewed in 50 patients (30 men and 20 women, mean age 65 years) who had undergone percutaneous transhepatic RPVE with AE under temporary balloon occlusion (TBO) between February 2002 and October 2009. The enhancement pattern before embolization and the embolization pattern after the first AE injection were analyzed by portography. The angles of portal branches against the horizontal plane were measured in 48 patients using pre-treatment CECT.

RESULTS

The enhancement pattern was not consistent with the embolization pattern in 35 patients (p < 0.001). When the anterior branch angles were divided into two groups at -5°, 0°, 10°, and 15°, the frequency of the posterior-branch-dominant embolization pattern was higher in the more negatively angled group (p = 0.002-0.041).

CONCLUSION

The distribution of AE is different from that of contrast medium in percutaneous transhepatic RPVE under TBO. The pre-treatment measurement of the angles of portal branches against the horizontal plane on CECT is suggested to be useful for predicting the embolized area.

Single-slice epicardial fat area measurement: do we need to measure the total epicardial fat volume?

PURPOSE

The aim of this study was to assess a method for measuring epicardial fat volume (EFV) by means of a single-slice area measurement. We investigated the relation between a single-slice fat area measurement and total EFV.

METHODS AND METHODS

A series of 72 consecutive patients (ages 65 ± 11 years; 36 men) who had undergone cardiac computed tomography (CT) on a 64-slice multidetector scanner with prospective electrocardiographic triggering were retrospectively reviewed. Pixels in the pericardium with a density range from -230 to -30 Hounsfield units were considered fat, giving the per-slice epicardial fat area (EFA). The EFV was estimated by the summation of EFAs multiplied by the slice thickness. We investigated the relation between total EFV and each EFA.

RESULTS

EFAs measured at several anatomical landmarks-right pulmonary artery, origins of the left main coronary artery, right coronary artery, coronary sinus-all correlated with the EFV (r = 0.77-0.92). The EFA at the LMCA level was highly reproducible and showed an excellent correlation with the EFV (r = 0.92).

CONCLUSION

The EFA is significantly correlated with the EFV. The EFA is a simple, quick method for representing the time-consuming EFV, which has been used as a predictive indicator of cardiovascular diseases.

Clonal distribution of enterotoxigenic Staphylococcus aureus on handles of handheld shopping baskets in supermarkets

AIMS

Shopping carts and handheld shopping baskets in supermarkets are subject to accidental bacterial contamination through contacts with a variety of food. We investigated the prevalence of Staphylococcus aureus on the handles of handheld shopping baskets in four supermarkets distantly located in Osaka district, Japan.

METHODS AND RESULTS

Fifty two strains of Staph. aureus were isolated from 760 basket handles. Among these, six strains were positive for staphylococcal enterotoxin B (SEB) production, representing 12% of total. This SEB producer ratio is considerably higher than among Staph. aureus isolated from nasal swabs of the supermarket workers (2%) and from independently collected clinical specimens (4%). These SEB-producing Staph. aureus strains from the basket handles are clonal and belong to ST12. Coagulase typing showed that they are in group VII, which is the most common cause of food poisoning in Japan. Biofilm assays indicated that SEB gene (seb)-positive strains including this clone produced a significantly higher amount of biofilm than seb-negative strains.

CONCLUSIONS

The frequent isolation of seb-positive Staph. aureus on shopping basket handles raises the possibility that they could be a hidden reservoir for Staph. aureus with a potential to cause food poisoning and draws attention to the importance of shopping basket sanitation.

Splenic volume measurements on computed tomography utilizing automatically contouring software and its relationship with age, gender, and anthropometric parameters

OBJECTIVE

The present research was conducted to establish the normal splenic volume in adults using a novel and fast technique. The relationship between splenic volume and age, gender, and anthropometric parameters was also examined.

MATERIALS AND METHODS

The splenic volume was measured in 230 consecutive patients who underwent computed tomography (CT) scans for various indications. Patients with conditions that have known effect on the spleen size were not included in this study. A new technique using volumetric software to automatically contour the spleen in each CT slice and quickly calculate splenic volume was employed. Inter- and intra-observer variability were also examined.

RESULTS

The average splenic volume of all the subjects was 127.4+/-62.9 cm(3), ranging from 22 to 417 cm(3). The splenic volume (S) correlated with age (A) (r=-0.33, p<0.0001), body weight (W) (r=0.35, p<0.0001), body mass index (r=0.24, p<0.0001) and body surface area (BSA) (r=0.31, p<0.0001). The age-adjusted splenic volume index correlated with gender (p=0.0089). The formulae S=W[6.47A(-0.31)] and S=BSA[278A(-0.36)] were derived and can be used to estimate the splenic volume. Inter- and intra-observer variability were 6.4+/-9.8% and 2.8+/-3.5% respectively.

CONCLUSION

Of the anthropometric parameters, the splenic volume was most closely linked to body weight. The automatically contouring software as well as formulae can be used to obtain the volume of the spleen in regular practice.

Identification of hemodialysis patients' common problems using the International Classification of Functioning, Disability and Health

The aim of this study was to identify the common health problems of Japanese patients on hemodialysis (HD) using the International Classification of Functioning, Disability and Health (ICF). The participants of this study had been on HD for at least five years when they were interviewed. The ICF checklist was used to initially interview 32 HD patients. Fifty-seven categories of the ICF Checklist were identified as impaired; another 35 ICF categories, chosen based on interviews and expert discussion, as well as 8 categories relevant to HD, were included in the final checklist. This final checklist was then used to interview 104 patients. Overall, 10 categories in "Body functions" and 3 categories in "Body structures" were reported as problems by more than 50% of patients. Two categories in "Activities and participation" and 4 categories in "Environmental factors" were reported as restricted or a barrier for more than 30% of patients. A higher percentage of patients who started HD before 50 years of age and had a longer duration of HD reported problems in "Body functions" and "Body structures", while more patients with a shorter duration of HD reported problems in relationships with their family. Japanese patients on maintenance HD have various physical and psychosocial problems. In addition, HD duration and the age when HD was started affect patients' reports of physical and psychosocial problems.

Effect of 8-MHz radiofrequency-capacitive regional hyperthermia with strong superficial cooling for unresectable or recurrent colorectal cancer

A well-known disadvantage of a radiofrequency-capacitive device for deep-seated tumours is preferential heating of the subcutaneous fat tissue. The authors previously developed the hyperthermia with their own external cooling unit and achieved strong superficial cooling, and reported its usefulness for the reduction of the preferential heating. The purpose of the present study was to evaluate the effect of hyperthermia with strong superficial cooling on the treatment results for unresectable or recurrent colorectal cancers. From 1986 to 2002, 44 patients with primary unresectable or locally recurrent colorectal cancer treated with thermoradiotherapy were analysed retrospectively. The patients with obesity as a subcutaneous fat thickness more than 3 cm, a high age or other serious complications did not undergo therapy. The results were compared between 17 cases with strong superficial cooling treated after 1997 (Group A) and 27 cases without strong superficial cooling treated before 1996 (Group B). Significant differences in thermometry data of T(max), T(ave) and T(min) were noted between Groups A (45.3, 44.4 and 43.6 degrees C, respectively) and B (42.9, 42.0 and 41.1 degrees C, respectively) (p<0.01). Complete response plus partial response rates were better for Group A than for Group B (59 versus 26%, p = 0.05). Multivariate analysis by logistic regression to evaluate the effects of certain factors on complete response plus partial response was strongly correlated with strong superficial cooling (p<0.05). The median survival times for overall survival were 24.3 months for Group A and 17.1 months for Group B (p<0.05). Eight-megahertz radiofrequency-capacitive regional hyperthermia with strong superficial cooling is potentially useful for improving treatment results in unresectable or recurrent colorectal cancers.

Reduction of bed rest time after transfemoral noncardiac angiography from 4 hours to 2 hours: a randomized trial and a one-arm study

PURPOSE

To evaluate the feasibility of shortening the bed rest time from 4 hours to 2 hours after transfemoral noncardiac angiography with a 4-F sheath (outer diameter, 1.93 mm), a 5-F sheath (outer diameter, 2.27 mm), and a 4-F catheter.

MATERIALS AND METHODS

Patients were randomized into two groups, receiving either 2 or 4 hours of bed rest after hemostasis by manual compression of the puncture site. The authors evaluated the frequency of bleeding complications. An interim analysis was performed wherein 40 patients were assigned to each group. After the analysis, a single-arm 2-hour bed rest trial was conducted in an additional 115 procedures.

RESULTS

In the interim analysis, three of the 40 patients in the 4-hour group and none of the 40 patients in the 2-hour group developed minor bleeding within 2 hours after manual compression (P = .24). After 2 hours of bed rest, no bleeding complication was observed in either group. In the single-arm 2-hour bed rest trial, minor bleeding developed in one of the 115 procedures (0.8%). Through the study, minor bleeding occurred in four of the 195 total procedures (2%), and no major complications developed. The occurrence of a bleeding complication was significantly higher in patients with platelet counts of less than 100 x 10(9)/L than in the other patients (4/67 vs 0/128, P = .01).

CONCLUSIONS

Two hours of bed rest is feasible for patients undergoing transfemoral noncardiac angiography by using a 4-5-F sheath and/or a 4-F catheter, especially those with a normal platelet count.

Influence of Surgical Staples on Radiofrequency Ablation Using Multitined Expandable Electrodes

PURPOSE

During radiofrequency ablation (RFA), there is a risk that the multitined expandable electrode will come into contact with one of the surgical staples used to treat local recurrence after surgical operations. Our objective was to evaluate whether a surgical staple would influence the RFA of egg white using a multitined expandable electrode.

METHODS

Multitined expandable electrodes, LeVeen needles (expandable diameter 3.0 cm), were sunk into an egg white bath with (a) no surgical staple, (b) a surgical staple touching one of the tines, or (c) a surgical staple touching two of the tines simultaneously. By connecting the LeVeen needle and copper plate at the bottom of the bath, RFA was then performed on the egg whites as a substitute for human tissue. Ten egg white baths were ablated under each of conditions (a), (b), and (c), for a total of 30 sets of coagulated egg white.

RESULTS

There was no significant difference in the time from the power-on to the roll-off (i.e., the completion and shutting off of the electric circuit) or in the maximum diameter of the thermal lesion between conditions (a) and (b) or (a) and (c). However, the minimum diameter of the thermal lesion was significantly smaller in (c) compared with (a) (p < 0.01).

CONCLUSIONS

Surgical staples have the capacity to interfere with the electromagnetic field and decrease the minimum diameter of the thermal lesion in the event that a staple touches two of the tines of a multitined expandable electrode during RFA. Although the difference might be small enough to be neglected under many clinical circumstances, we recommend that, if possible, the tines not be expanded near metallic material.

Codeine presynaptically inhibits the glutamatergic synaptic transmission in the nucleus tractus solitarius of the guinea pig

Although codeine is the most prominent and centrally acting antitussive agent, the precise sites and mode of its action have not been fully understood yet. In the present study, we examined the effects of codeine on synaptic transmission in second-order neurons of the nucleus tractus solitarius (NTS), which is the first central relay site receiving tussigenic afferent fibers, by using whole-cell patch-clamp recordings in guinea-pig brainstem slices. Codeine (0.3-3 mM) significantly decreased the amplitude of excitatory postsynaptic currents (EPSCs) evoked by electrical stimulation of the tractus solitarius in a naloxone-reversible and concentration-dependent manner, but it had no effect on the decay time of evoked EPSCs (eEPSCs). The inhibition of eEPSCs was accompanied by an increased paired-pulse ratio of two consecutive eEPSCs. The inward current induced by application of AMPA remained unchanged after codeine application. A voltage-sensitive K+ channel blocker, 4-aminopyridine (4-AP) attenuated the inhibitory effect of codeine on eEPSCs. These results suggest that codeine inhibits excitatory transmission from the primary afferent fibers to the second-order NTS neurons through the opioid receptors that activate the 4-AP sensitive K+ channels located at presynaptic terminals.

Radiotherapy with 8 MHz radiofrequency-capacitive regional hyperthermia for pain relief of unresectable and recurrent colorectal cancer

PURPOSE

The purpose of this study was to assess the pain relief in patients with unresectable and recurrent colorectal cancer treated with radiation plus 8 MHz radiofrequency-capacitive regional hyperthermia and to identify predictors of the good outcome.

METHODS

Between February 1986-May 2003, 41 patients with primarily unresectable and recurrent colorectal cancer that caused pain were treated with thermoradiotherapy at the hospital and retrospectively analysed. Radiotherapy was administered with a mean total radiation dose of 56 Gy. Hyperthermia was usually applied within 30 min after radiotherapy once or twice a week. For cooling of the skin surface, the overlay boluses were applied in addition to regular boluses. The external cooling unit has been used to reinforce the cooling ability of the overlay bolus and achieve strong surface cooling to reduce the preferential heating of the subcutaneous fat tissue and treat with more RF-output in 17 patients since January 1997.

RESULTS

Pain relief was obtained in 83% of the patients. Multi-variate analysis by logistic regression to evaluate the effects of certain factors on pain relief (complete response + good response) was strongly correlated with the presence of radiating pain to leg(s) (p < 0.05). The median follow-up was 18 months. The median duration of pain relief was 7.0 months. For the 27 patients in whom the tumour temperature was estimated, the median duration of pain relief was 14.6 months for the patients with a mean average tumour temperature of > 42.5 degrees C and 5.7 months for those of < 42.5 degrees C (p < 0.05). In the 18 patients with radiating pain to leg(s), use of strong superficial cooling and the higher numbers of hyperthermia treatments were better prognostic factors for the duration of pain relief (p < 0.01 and p < 0.05, respectively).

CONCLUSIONS

Radiotherapy with 8 MHz radiofrequency-capacitive regional hyperthermia provided an efficient, effective means on pain relief of treating unresectable and recurrent colorectal cancer. The duration of pain relief can be prolonged, if an adequate heating is achieved, especially in the patients with radiating pain to the leg(s).