Influence of parameter settings in voxel-based morphometry 8. Using DARTEL and region-of-interest on reproducibility in gray matter volumetry

OBJECTIVES

To investigate whether reproducibility of gray matter volumetry is influenced by parameter settings for VBM 8 using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) with region-of-interest (ROI) analyses.

METHODS

We prepared three-dimensional T1-weighted magnetic resonance images (3D-T1WIs) of 21 healthy subjects. All subjects were imaged with each of five MRI systems. Voxel-based morphometry 8 (VBM 8) and WFU PickAtlas software were used for gray matter volumetry. The bilateral ROI labels used were those provided as default settings with the software: Frontal Lobe, Hippocampus, Occipital Lobe, Orbital Gyrus, Parietal Lobe, Putamen, and Temporal Lobe. All 3D-T1WIs were segmented to gray matter with six parameters of VBM 8, with each parameter having between three and eight selectable levels. Reproducibility was evaluated as the standard deviation (mm³) of measured values for the five MRI systems.

RESULTS

Reproducibility was influenced by 'Bias regularization (BiasR)', 'Bias FWHM', and 'De-noising filter' settings, but not by 'MRF weighting', 'Sampling distance', or 'Warping regularization' settings. Reproducibility in BiasR was influenced by ROI. Superior reproducibility was observed in Frontal Lobe with the BiasR1 setting, and in Hippocampus, Parietal Lobe, and Putamen with the BiasR3*, BiasR1, and BiasR5 settings, respectively.

CONCLUSION

Reproducibility of gray matter volumetry was influenced by parameter settings in VBM 8 using DARTEL and ROI. In multi-center studies, the use of appropriate settings in VBM 8 with DARTEL results in reduced scanner effect.

BMI is associated with larger index tumors and worse outcome after radical prostatectomy

BACKGROUND

To investigate the impact of body mass index (BMI) on tumor characteristics and biochemical recurrence (BCR) after radical prostatectomy (RP) for prostate cancer (PCa) in Japanese men.

METHODS

We evaluated data from consecutive patients who had undergone RP. Data analyzed included age, preoperative serum PSA, prostatic volume, BMI (continuous or categorized (≤ 25 kg/m(2)) values), clinical and pathological findings including index tumor volume (ITV), and current status in areas such as smoker or nonsmoker and presence or absence of diabetes. We analyzed association between BMI and BCR, especially based on ITV using univariate and multivariate analysis.

RESULTS

We analyzed data from a total of 703 patients. The median follow-up time was 38.4 months. BCR was diagnosed in 154 patients (21.9%) at a median of 9.7 months postoperatively. Multivariate linear regression analysis adjusted for preoperative variables showed a significant positive association between BMI and ITV (continuous BMI: P=0.002; categorical BMI: P<0.001, respectively), especially for higher-grade tumors (Gleason score ≥ 7). Cox proportional hazards analysis showed a significant association between continuous BMI and BCR after surgery (preoperative variables, hazard ratio (HR) 1.09, 95% confidence interval (CI) 1.02-1.16, P=0.008), independent of clinical and pathological findings. In patients with high-risk cancer, the positive association between BMI and BCR was strengthened (preoperative variables, continuous BMI, HR 1.16, 95% CI 1.07-1.26, P<0.001; categorical BMI, HR 2.11, 95% CI 1.29-3.45, P=0.003, respectively).

CONCLUSIONS

Greater BMI significantly correlates with higher rates of BCR after surgery; BMI is a preoperative variable associated with high-grade ITV. Our results suggest that the biological environment created by greater BMI may contribute to increasing tumor aggressiveness.

The number of chews and meal duration affect diet-induced thermogenesis and splanchnic circulation

OBJECTIVE

To determine the effects of the number of chews and meal duration on diet-induced thermogenesis (DIT) and splanchnic blood flow (BF).

METHODS

Healthy normal-weight subjects (11 subjects in the 100-kcal test and 10 subjects in the 300-kcal test) participated in two trials: a rapid-eating trial and a slow-eating trial. The meal duration and the number of chews were recorded. DIT was calculated from oxygen uptake and body mass, and splanchnic BF was calculated from the diameters of and blood velocities in the celiac artery and superior mesenteric artery, which were recorded until 90 min after consuming the food samples.

RESULTS

For the 100-kcal and 300-kcal food samples, DIT and postprandial splanchnic BF in both the celiac artery and superior mesenteric artery were significantly larger in the slow-eating trial than in the rapid-eating trial. There were significant correlations among meal duration, the number of chews, DIT, and postprandial splanchnic BF, with the exception of the relationship between DIT and splanchnic BF in the 300-kcal trial.

CONCLUSIONS

These results suggest that fewer chews and/or shorter meal duration decreases DIT and the postprandial splanchnic BF, and that the increased DIT is at least partially due to the postprandial splanchnic circulation.

Cerebral blood flow and neurovascular coupling during static exercise

The effect of static exercise on neurovascular coupling (NVC) was investigated by measuring the blood flow velocity in the posterior cerebral artery (PCAv) during 2-min static handgrip exercises (HG) at 30 % of the maximum voluntary contraction in 17 healthy males. NVC was estimated as the relative change in PCAv from eye closing to a peak response to looking at a reversed checkerboard. The conductance index (CI) was calculated by dividing PCAv by the mean arterial pressure (MAP). HG significantly increased PCAv from the resting baseline, with an increase in MAP and a reduction in CI, whereas NVC did not differ significantly between the resting and HG. Compared to the resting baseline, HG significantly increased the pressor response to visual stimulation by 5.6 ± 1.1 (mean ± SE) mmHg, while the CI response was significantly inhibited by -7.0 ± 1.5 %. These results indicate that NVC was maintained during HG via contributions from both the pressor response and vasodilatation.

Risk factors for hepatocellular carcinoma in hepatitis C patients with normal alanine aminotransferase treated with pegylated interferon and ribavirin

Pegylated interferon (Peg-IFN) plus ribavirin combination therapy is effective in patients with hepatitis C virus (HCV) infection and normal alanine aminotransferase levels (NALT). However, it remains unclear whether the risk of hepatocellular carcinoma (HCC) incidence is actually reduced in virological responders. In this study, HCC incidence was examined for 809 patients with NALT (ALT ≤ 40 IU/mL) treated with Peg-IFN alpha-2b and ribavirin for a mean observation period of 36.2 ± 16.5 months. The risk factors for HCC incidence were analysed by Kaplan-Meier method and Cox proportional hazards model. On multivariate analysis among NALT patients, the risk of HCC incidence was significantly reduced in patients with sustained virological response (SVR) or relapse compared with those showing nonresponse (NR) (SVR vs NR, hazard ratio (HR): 0.16, P = 0.009, relapse vs NR, HR: 0.11, P = 0.037). Other risk factors were older age (≥65 years vs <60 years, HR: 6.0, P = 0.032, 60-64 vs <60 years, HR: 3.2, P = 0.212) and male gender (HR: 3.9, P = 0.031). Among 176 patients with PNALT (ALT ≤ 30 IU/mL), only one patient developed HCC and no significant risk factors associated with HCC development were found. In conclusion, antiviral therapy for NALT patients with HCV infection can lower the HCC incidence in responders, particularly for aged and male patients. The indication of antiviral therapy for PNALT (ALT ≤ 30 IU/mL) patients should be carefully determined.

Palatability of tastes is associated with facial circulatory responses

To examine whether various types of taste stimuli in the oral cavity elicit unique changes in facial skin blood flow (SkBF) according to the palatability perceived by an individual, the facial SkBF was observed by laser speckle flowgraphy in 15 healthy subjects (11 males and 4 females) before and during the ingestion of bitter tea, chilli sauce, coffee, orange juice, soup, and a water control. The heart rate, mean arterial pressure (MAP), and SkBF in the index finger were recorded continuously. Subjects reported their subjective palatability and taste intensity scores after each stimulus. The vascular conductance indexes (CIs) in the face and finger were calculated as ratios of SkBF to MAP. CI in the eyelid increased significantly in response to chilli sauce, orange juice, and soup, whereas CIs in the forehead, nose, and cheek decreased in response to bitter tea. There was a significant correlation between the palatability scores and CI values in the eyelid when changes induced by chilli sauce were excluded. These results suggest that the facial circulatory response reflects the degree of palatability of a foodstuff.

Effects of heat stress on ocular blood flow during exhaustive exercise

The hypothesis that heat stress reduces the ocular blood flow response to exhaustive exercise was tested by measuring ocular blood flow, blood pressure, and end- tidal carbon dioxide partial pressure (PETCO2) in 12 healthy males while they performed cycle ergometer exercise at 75% of the maximal heart rate at ambient temperatures of 20°C (control condition) and 35°C (heat condition), until exhaustion. The blood flows in the retinal and choroidal vasculature (RCV), the superior temporal retinal arteriole (STRA) and the superior nasal retinal arteriole (SNRA) were recorded at rest and at 6 and 16 min after the start of exercise period and at exhaustion [after 16 ± 2 min (mean ± SE) and 24 ± 3 min of exercise in the heat and control condition, respectively]. The mean arterial pressure at exhaustion was significantly lower in the heat condition than in the control condition at both 16 min and exhaustion. The degree of PETCO2 reduction did not differ significantly between the two thermal conditions at either 16 min or exhaustion. The blood flow velocity in the RCV significantly increased from the resting baseline value at 6 min in both thermal conditions (32 ± 6% and 25 ± 5% at 20°C and 35°C, respectively). However, at 16 min the increase in RCV blood flow velocity had returned to the resting baseline level only in the heat condition. At exhaustion, the blood flows in the STRA and SNRA had decreased significantly from the resting baseline value in the heat condition (STRA: -19 ± 5% and SNRA: -30 ± 6%), and SNRA blood flow was lower than that in the control condition (-14 ± 6% vs -30 ± 6% at 20°C and 35°C, respectively), despite the finding that both thermal conditions induced the same reductions in PETCO2 and vascular conductance. These findings suggested that the heat condition decreases or suppresses ocular blood flow via attenuation of pressor response during exhaustive exercise. Key PointsThe ocular (retinal and choroidal) blood flow response to exhaustive exercise with heat stress is unknown.We hypothesized that the heat stress decreases ocular blood flow response to exhaustive exercise, since cerebral flow, which is regulated similarly to ocular flow, was reported to decrease during heat stress.To test this hypothesis, ocular blood flow was measured during exhaustive exercise at 20°C (control condition) and 35°C (heat condition).At exhaustion in the heat condition, the ocular flow response was suppressed or decreased with an attenuated pressor response.It is suggested that the heat condition decreases or suppresses the ocular blood flow to exhaustive exercise via attenuation of pressor response.

Endocardial Invasion of Lung Cancer Undiagnosable before Autopsy

A 59-year-old male patient presented with left chest discomfort on admission. His medical history included encephalitis in childhood and his smoking history was 20 cigarettes per day for 40 years. A physical examination showed an anemic and edematous face with weak respiratory sounds in the left lung. The patient had elevated calcium levels and decreased hemoglobin and potassium. His parathyroid hormone-related protein level was elevated. Thoracic radiography showed cardiomegaly and computed tomography revealed a left lung mass with invasion of the heart and pleural effusion. Magnetic resonance imaging showed endocardial invasion of the tumor mass. Gallium-68 imaging revealed positive accumulation in the region surrounding the heart. No diagnoses were possible upon frequent cytology of his sputum and pleural effusion. The patient died from congestive heart failure with anoxia 38 days after admission. An autopsy revealed tumoral mass occlusion in the left main bronchus and tumoral invasion of the left atrium, left ventricle, and aorta.

Abstract P3-14-10: Conversion to node-negative after neoadjuvant chemotherapy is a surrogate prognostic marker in patients with hormone receptor-positive breast cancer

Background: While pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) improves patients’ survival with HER2-positive and triple-negative (TN) breast cancers, it has been reported not to be the same for patients with hormone receptor (HR)-positive breast cancer. However, it is not well known whether chemosensitivity presented by change in tumor stage or nodal status after NAC contributes to improve the prognosis with HR-positive breast cancer. The aim of this study was to evaluate the impact of change in tumor stage or nodal status after NAC on prognosis in patients with primary breast cancer.

Patients and Methods: We assessed retrospectively 599 consecutive patients with primary breast cancer (a median age of 49 years, ranging 26-79 years) who underwent surgical resection after NAC between 2001 and 2008. HR (ER and PR) statuses were determined by immunohistochemistory (IHC). HER2 status was determined by IHC and/or fluorescent in situ hybridization assays. ER-positive and PR-positive patients were 426 (71.1%) and 353 patients (58.9%), respectively. HER2 status was positive in 130 patients (21.7%). HR-positive subtype was defined as ER and/or PR-positive and HER2 negative. We compared the patients with respect to disease-free survival (DFS) and overall survival (OS) based on change in tumor stage and nodal status after NAC. pCR was defined as no residual invasive tumor and ypN0.

Results: After NAC, 84 (14.0%) patients had pCR. Two hundred ninety one (48.6%) decreased tumor stage and 308 (51.4%) did not decrease tumor stage. Regarding nodal status, 190 (31.7%) had cN0 and 409 (68.3%) had cN+ before NAC, and 286 had ypN0 (47.7%) and 313 had ypN+ (52.2%). For patients with TN breast cancer, patients with pCR had excellent prognosis compared to those with residual tumor in either the breast or lymph node (non-pCR) (DFS, p&lt;0.01, and OS, p = 0.035, respectively). Among the non-pCR group, patients with ypN0 also have longer DFS and OS than patients with ypN+ (p&lt;0.01, and p = 0.031, respectively). However, for ypN0 patients with TN breast cancer, patients with residual primary tumor had significantly shorter DFS and OS than patients with ypT0. For HR-positive breast cancer patients, there was a trend that patients with pCR had better DFS than patients with non-pCR (p = 0.069). In terms of OS, there was no significant difference between pCR and non-pCR (p = 0.285). Patients with ypN0 had significantly longer DFS and OS than those with ypN+ regardless of residual tumor stage (p&lt; 0.001 and p = 0.01, respectively). Change in tumor stage itself did not contribute to improve patients’ survival.

Conclusions: Our results revealed that HR-positive breast cancer patients with conversion to lymph nodes metastasis after NAC have a good prognosis even if they have residual tumor in the breast, while TN breast cancer patients require pCR to have a good prognosis. It indicated that conversion to node-negative after neoadjuvant chemotherapy might be a surrogate prognostic marker in patients with HR-positive breast cancer.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-14-10.

Abstract P4-05-09: Estrogen receptor (ER) mRNA expression and molecular subtype distribution in breast cancers that are ER-negative but progesterone receptor-positive by immunohistochemistory

Purpose: We examined Estrogen receptor (ER) mRNA expression and molecular subtypes in breast cancers that are Progesterone receptor (PR) positive but ER negative by immunohistochemistry (IHC) to assess if these cancers molecularly resemble true ER positive cancers.

Patients and Methods: Patients were those with newly diagnosed ERBB2-negative breast cancer treated with neoadjuvant chemotherapy containing sequential taxane and antheracycline-based regimens (then endocrine therapy if ER-positive by IHC). ER and PR status was determined by IHC in 501 primary breast cancers in routine pathology laboratory. Gene expression profiling was done with the Affymetrix U133A gene chip (Gene Expression Omnibus number: GSE25066). We compared expressions of ESR1, MKI67 mRNA and molecular subtypes determined by the PAM 50 classifier between IHC-ER-positive/PR-positive (n = 223), ER-positive/PR-negative (n = 73), ER-negative/PR-positive (n = 20), and ER-negative/PR-negative (n = 185) cancers. We also plotted survival curves by ER and PR status based on IHC.

Results: ER or PR positivity by IHC was defined ≥ 1% staining. ER positivity by ESR1 mRNA expression was defined as &gt; 10.18 previously published. Among the IHC-ER-negative/PR-positive, ER-positive/PR-negative, and both ER/PR-positive, and ER/PR-negative patients, 25%, 79%, 96% and 12% were positive by ESR1 mRNA expression, respectively. The average ESR1 expression was significantly higher in the ER/PR-positive and ER-positive/PR-negative cohorts compared with the ER-negative/PR-positive or ER/PR-negative cohorts. The average MKI67 mRNA expression was significantly higher in the ER-negative/PR-positive and ER/PR-negative cohorts. Among the ER-negative/PR-positive patients, 15% were luminal A, 5% were Luminal B, and 65% were basal like; among the ER-positive/PR-negative patients, 59% were luminal type. The relapse free survival rate of ER-negative/PR-positive patients was equivalent to ER/PR-positive or ER-positive/PR-negative, and significantly better than that of the ER-negative/PR-negative cohort.

Conclusion: Only 20-25% of the ER-negative/PR-positive tumors show molecular features of ER-positive cancers (i.e high ER mRNA expression and luminal molecular class). These cancers also have higher proliferation rate than ER-positive cancer. However, the survival of these cancers with only chemotherapy is similar to ER-positive cancers with chemotherapy and endocrine therapy, and is better than ER-negative cancers. The contribution of endocrine therapy to this good outcome is to be invested in the future.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-05-09.

Abstract P2-18-03: Feasibility of sentinel node biopsy following neoadjuvant chemotherapy in cytology-proven node positive breast cancer before chemotherapy

BACKGROUND: Sentinel node biopsy (SNB) for the node negative breast cancer is standard treatment as an accurate assessment of axillary lymph node status; however, axillary node dissection is a standard procedure for the node positive breast cancer. Neoadjuvant chemotherapy (NAC) has become the standard of care for patients with locally advanced breast cancer. It is reported that 40% of node positive disease convert to node negative after NAC. It remains controversial whether SLB could be applied to patients who present with node-positive disease before neoadjuvant chemotherapy. In this study, we evaluated the accuracy of SNB following NAC in breast cancer patients presenting with cytology-proven axillary node metastasis before chemotherapy.

METHODS: A multicenter prospective study was performed from September 2011 to April 2013 in 101 breast cancer patients with positive axillary nodes, proven by ultrasound-guided fine-needle aspiration at initial diagnosis (T1-3, N1, M0). After the confirmation of patients as clinically node-negative by preoperative imaging following NAC, all patients underwent breast surgery, with SNB and complete axillary lymph node dissection. The sentinel nodes were examined by hematoxylin-eosin staining, immunohistochemical analysis or one-step nucleic acid amplification assay (OSNA).The false negative rate and detection rate were analyzed.

RESULTS: Among the 101 patients analyzed, all cases presented with invasive ductal carcinoma. with a mean tumor size of 3.4cm. Thirty-six cases were hormone receptor (HR) positive and HER2 negative (Lum), 14 cases were HR positive and HER2 positive (Triple-Positive), 27 cases were positive for HER2 (HER2-enriched), and 24 cases were Triple-Negative. After neoadjuvant chemotherapy, a complete clinical response in the primary tumor was seen in 24.8%(25/101), a partial response in 66.3%(67/101), and no response in 7.9%(8/101). Pathological complete response of primary tumor was 39.6%. The pathological complete nodal response rate was 42.2%. The sentinel lymph node could be identified in 91 of 101 cases (90.1%); 88.9% (32/36) of patients with Lum, 100%(14/14)of those with Triple-Positive, 85.2% (23/27) of those with HER2-enriched, and 91.7% (22/24)% of those with Triple-Negative breast cancer subtype. The false negative rate was 12.7%; 35.7 (5/14) for Lum, 0% (0/8) for Triple-Positive, 5.0% (1/20) for HER2-enriched, and 7.7% (1/13) for Triple-Negative subtype (P = 0.03).

CONCLUSION: SNB following NAC in patients with node-positive breast cancer was found to be technically feasible, but is not recommended for the Lum subtype. However, it might be safely considered in selected patients, those with Triple-Positive, HER2-enrich and Triple-Negative subtype breast cancers.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-18-03.