MR quantification of abnormal stromal enhancement in the periphery of invasive breast tumors

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Background: In dynamic contrast-enhanced MRI (DCEMRI), properties of tissue microvasculature and overall vascularity can be quantified using kinetics of contrast enhancement. It has been shown that areas with high signal enhancement ratio (SER) were significantly correlated with high tumor vascularity, and that mean SER in nearby non-cancerous breast stroma was significantly associated with disease free survival. No universally accepted methods exist to determine the optimal extent of histologically normal breast tissue to treat. Although a relationship between normal tissue SER and recurrence has been observed, the spatial relationship of enhancement within the non-cancerous stroma with respect to proximity of the tumor has not been shown. We hypothesized that abnormalities in vasculature exist within the histologically normal breast stroma that can be detected by measuring changes in enhancement intensity. Methods: We performed a secondary analysis of pre-treatment DCEMRI data from 27 invasive breast cancer patients. An automated, user-independent program was used to segment breast tissue from all other structures. A SER threshold was set to identify invasive tumor regions, and a tumor proximity map was generated giving the 3D distance of each normal breast tissue voxel to the nearest tumor voxel. A percent enhancement (PE) map was calculated for the normal stroma using the signal intensity change between the pre-contrast and post-contrast images. The proximity and PE maps were then combined to measure breast tissue enhancement at various distances from the tumor. Results: PE levels in normal breast tissue situated within 2 cm of the tumor region were significantly higher than at all more distant regions. Pairwise comparisons with Turkey's adjusted p-values indicated that the mean PE at 0 cm-1 cm is significantly higher than all other distant levels (p = < 0.0001) and the mean PE at 1 cm-2 cm is significantly higher than 5 cm-6 cm (p = 0.006). Conclusions: Here, we show that the normal-appearing breast stroma within 0 cm to 2 cm of a primary tumor exhibits higher enhancement levels than stroma located far from the tumor. These results suggest that tissue surrounding the tumor region may contain tumor-related angiogenesis. These findings could help personalize surgery and radiation techniques.

No significant financial relationships to disclose.

Phase II study of S-1 monotherapy in taxane, cisplatin refractory gastric cancer

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Background: S-1 is a fourth-generation oral fluoropyrimidine that was developed to mimic protracted continuous infusion of 5-fluorouracil (5-FU). In previous study, S-1 demonstrated promising activity which is comparable to combination chemotherapy in advanced gastric cancer. This phase II study evaluated the efficacy and safety of S-1 salvage chemotherapy, in patients with taxane and cisplatin refractory gastric cancer. The primary end point was progression free survival and secondary end points were overall survival, safety and clinical benefit. Methods: Patients were eligible if they had histologically documented gastric adenocarcinoma previously treated with taxane (docetaxel or paclitaxel) and cisplatin; age≥18; Eastern Clinical Oncology Group (ECOG) performance status of 2 or less; adequate organ function; no evidence of gastrointestinal obstruction or passage disturbance. S-1 treatment was performed according to BSA as followed; < BSA 1.25, 80 mg/day, 1.25 ≤ BSA < 1.5, 100 mg/day; BSA ≥ 1.5, 120 mg/day. Every dosage was delivered divided two times and administered for 4 weeks followed by 2 weeks of resting period. Treatment continued until progression of disease or life-threatening adverse events were occurred. Results: Fifty-four patients were enrolled in this study and of the patients, forty-eight patients were evaluable. A total 194 chemotherapy cycles were administered and median number of cycles was three. Four (8.3%) patients had a partial response and 18 (37.5%) patients had stable disease. The median progression free survival and overall survival were 3.8 and 10.2 months, respectively. Grade III/IV hematologic toxicities included neutropenia in 6 patients (12.5%) and there was no febrile neutropenia. Most of nonhematologic toxicities were diarrhea, asthenia, and mucositis, and there was no grade 3 or grade 4 except two patients, who developed grade 3 anorexia and diarrhea, respectively. The clinical benefit response was observed in 16 patients (33.3%). Conclusions: This results showed that S-1 monotherapy was active and safe salvage chemotherapy in patients with advanced gastric cancer previously treated with taxane and cisplatin.

No significant financial relationships to disclose.

Predictive role of 18F-FDG-PET/CT 1 month before and after hypofractionated stereotactic body radiation therapy for stage I non-small cell lung cancer

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Background: To know the predictive role of 18F-FDG-PET/CT 1month before and after stereotactic body radiation therapy (SBRT) to stage I non-small cell lung cancer (NSCLC). Methods: Between 2004 and 2007, 20 patients received SBRT with 48 Gy for 4 consecutive days and checked two times of FDG- PET/CT and chest CT with contrast-enhancement at 1 month before and after SBRT. Change of maximal SUV (SUVmax) on FDG-PET/CT and the longest tumor diameter on chest CT before and after SBRT was measured. Patients only with high FDG uptake, SUVmax 3.0 or above, on FDG-PET/CT before SBRT and tumor diameter below 5 cm were analyzed in this study. Change of tumor diameter was classified to PR (partial response), SD (stable disease), and DP (disease progression) as RECIST criteria and change of SUVmax was described as % change. Chest CT was checked at every 3 or 6 months during follow-up. Results: Mean time intervals from SBRT to FDG-PET/CT and chest CT were 32 and 30 days respectively. Mean longest tumor diameter was changed from 2.59 cm (1.36–3.93) to 2.17 cm (1.18–3.41), and its reduction rate was -16.2%. By RECIST criteria, 4 patients showed PR, 15 patients showed SD, and other 1 patient showed DP. Mean decrease rate of SUVmax on FDG-PET/CT was -52.1% and its mean value was changed from 7.1 (3.2–13.1) to 3.4 (0.3–9.8). Median follow-up time was 16 months. Local tumor progression developed in 2 (10%) patients and time to progression was 3.4, 6.1 months. Tumor responses on post-SBRT chest CT were PR in 1 and SD in the other 1 patient, and SUVmax changes were -31.9%, -25.5% in each. Most of patients showing no response, SD or DP, didn't recur after SBRT, and so chest CT at 1 month could not predict actuarial tumor response. On the contrary to chest CT, no patients showing SUVmax decreases over 40% experienced tumor progression after SBRT. High decrease rate of SUVmax over 40% decrease on FDG-PET/CT 1 month after SBRT could warrant good actuarial local tumor control earlier. Conclusions: Change of SUVmax on FDG-PET/CT 1 month before and after SBRT could predict actuarial local tumor control of stage I NSCLC earlier and 1 month after SBRT was adequate timing for the earlier evaluation of tumor response.

No significant financial relationships to disclose.

Positive impact of radiation dose on disease free survival and locoregional control in postoperative radiotherapy for squamous cell carcinoma of esophagus

The effect of total radiation dose (TRD) on the outcome of patients with postoperative radiotherapy (RT) for squamous cell carcinoma of esophagus was assessed. Sixty-seven patients with esophagectomy, followed by postoperative RT for squamous cell carcinoma of esophagus from June 1984 through February 2001, were retrospectively reviewed. Of these, 13 patients were excluded. No patient had chemotherapy. Patients were classified into two groups based on TRD delivered: TRD of less than 50 Gy (Group A, n = 16) and at least 50 Gy (Group B, n = 38). Follow-up duration of all patients ranged from 4 to 140 months (median, 14). Median TRD of Group A and B were 45 Gy (range, 45-48.6) and 54 Gy (range, 50-59.6), respectively. Median overall survival (OS) and disease-free survival (DFS) of all patients were 15 and 10 months, respectively. Although the TRD of 50 Gy or higher was marginally significant for improved OS (hazard ration [HR] 0.559, P = 0.066), it was statistically significant for improved DFS (HR 0.398, P = 0.011), and locoregional recurrence-free survival (HR 0.165, P = 0.001) with multivariate analysis. Three patients in group A and two in group B experienced a complication of grade 3 or higher. Our study suggests a positive impact of TRD of 50 Gy or higher on DFS and locoregional control, with acceptable morbidity in postoperative RT for patients with squamous cell carcinoma of esophagus. According to the present analysis, TRD should be at least 50 Gy in postoperative RT alone setting.

Image contrast in X-ray reflection interface microscopy: comparison of data with model calculations and simulations

The contrast mechanism for imaging molecular-scale features on solid surfaces is described for X-ray reflection interface microscopy (XRIM) through comparison of experimental images with model calculations and simulated measurements. Images of elementary steps show that image contrast is controlled by changes in the incident angle of the X-ray beam with respect to the sample surface. Systematic changes in the magnitude and sign of image contrast are asymmetric for angular deviations of the sample from the specular reflection condition. No changes in image contrast are observed when defocusing the condenser or objective lenses. These data are explained with model structure-factor calculations that reproduce all of the qualitative features observed in the experimental data. These results provide new insights into the image contrast mechanism, including contrast reversal as a function of incident angle, the sensitivity of image contrast to step direction (i.e. up versus down), and the ability to maximize image contrast at almost any scattering condition defined by the vertical momentum transfer, Q(z). The full surface topography can then, in principle, be recovered by a series of images as a function of incident angle at fixed momentum transfer. Inclusion of relevant experimental details shows that the image contrast magnitude is controlled by the intersection of the reciprocal-space resolution function (i.e. controlled by numerical aperture of the condenser and objective lenses) and the spatially resolved interfacial structure factor of the object being imaged. Together these factors reduce the nominal contrast for a step near the specular reflection condition to a value similar to that observed experimentally. This formalism demonstrates that the XRIM images derive from limited aperture contrast, and explains how non-zero image contrast can be obtained when imaging a pure phase object corresponding to the interfacial topography.

Morphometric evaluation of oesophageal wall in patients with nutcracker oesophagus and ineffective oesophageal motility

The pathogenesis of nutcracker oesophagus (NE) and ineffective oesophageal motility (IEM) is unclear. Damage to the enteric nervous system or smooth muscle can cause oesophageal dysmotility. We tested the hypothesis that NE and IEM are associated with abnormal muscular or neural constituents of the oesophageal wall. Oesophageal manometry was performed in patients prior to total gastrectomy for gastric cancer. The oesophageal manometries were categorized as normal (n = 7), NE (n = 13), or IEM (n = 5). Histologic examination of oesophageal tissue obtained during surgery was performed after haematoxylin and eosin (H&E) and trichrome staining. Oesophageal innervation was examined after immunostaining for protein gene product-9.5 (PGP-9.5), choline acetyltransferase (ChAT) and neuronal nitric oxide synthase (nNOS). There were no significant differences in inner circular smooth muscle thickness or degree of fibrosis among the three groups. Severe muscle fibre loss was found in four of five patients with IEM. The density of PGP-9.5-reactive neural structures was not different among the three groups. The density of ChAT immunostaining in the myenteric plexus (MP) was significantly greater in patients with NE (P < 0.05) and the density of nNOS immunostaining in the circular muscle (CM) was significantly greater in IEM patients (P < 0.05). The ChAT/nNOS ratio in both MP and CM was significantly greater in NE patients. NE may result from an imbalance between the excitatory and inhibitory innervation of the oesophagus, because more than normal numbers of ChAT-positive myenteric neurones are seen in NE. Myopathy and/or increased number of nNOS neurones may contribute to the hypocontractile motor activity of IEM.

Solid pseudopapillary carcinoma of the pancreas: differentiation from benign solid pseudopapillary tumour using CT and MRI

AIM

To describe the computed tomography (CT) and magnetic resonance imaging (MRI) findings that differentiate solid pseudopapillary carcinomas (SPC) from benign solid pseudopapillary tumours (SPT) of the pancreas.

MATERIALS AND METHODS

Preoperative CT or MRI images for 26 patients (eight patients with SPC and 18 patients with SPT) were retrospectively reviewed. In addition to the general morphological features, the presence of pancreatic duct dilation, vascular invasion, and extrapancreatic metastases were comparatively assessed.

RESULTS

There were no significant differences between pancreatic SPC and benign SPT with respect to tumour size, location, capsule thickness, internal composition, and pattern of calcification, nor was there any correlation with the age and gender of the patients. Pancreatic duct dilation was present in four of the eight (50%) SPC patients, and was absent in all benign SPT patients (p=0.005). Vascular encasement by the tumour (n=2) and hepatic metastases (n=2) were also exclusively demonstrated in SPC patients. Multivariate logistic regression analysis showed that pancreatic duct dilation (p=0.001), vessel encasement (p=0.027), and metastasis (p=0.027) were the variables that can be used to differentiate SPC from benign SPT.

CONCLUSION

SPC of the pancreas may help to differentiate from benign SPT using the imaging features of aggressive behaviour of pancreatic duct dilation and vessel encasement with or without extrapancreatic metastases.

A new HLA-B*40 variant, B*4073, identified by sequence-based typing in the Korean population

A novel human leukocyte antigen-B*40 (HLA-B*40) allele was identified in the Korean population and designated HLA-B*4073. The HLA-B*4073 allele shows one nucleotide difference from B*400102 in exon 2 at nucleotide position 299 (A-->T), resulting in an amino acid change, Glu76Val.

A new HLA-A*24 variant, A*2475, identified by sequence-based typing in the Korean population

A novel human leukocyte antigen (HLA) A*24 allele was identified in the Korean population and designated HLA-A*2475. The HLA-A*2475 allele shows one nucleotide difference from A*24020101 in exon 3 at nucleotide position 575 (T-->C), resulting in an amino acid change, Leu168Arg.