Proton and Carbon Ion Radiotherapy for Operable Early-Stage Lung Cancer: 3-Year Results of a Prospective Nationwide Registry

PURPOSE/OBJECTIVE(S)

The purpose of this analysis was to report subset analysis as to progression-free survival (PFS) and overall survival (OS) of particle-beam radiation therapy for operable early-stage lung cancer.

MATERIALS/METHODS

Patients of early-stage lung cancer (T1-T2aN0) who were eligible for radical surgery but did not wish to undergo surgery were treated by proton-ion (PT) or carbon-ion (CT) radiation therapy and enrolled in Japanese prospective registry. In this analysis, PFS and OS by clinical stage, tumor location, pathological confirmation and particle-ion type were evaluated.

RESULTS

A total of 274 patients were enrolled and included in efficacy and safety analyses. Most tumors were adenocarcinoma (44%), and 105 (38%) were not histologically confirmed and diagnosed clinically. 250 (91%) of 274 patients had tumors that were peripherally situated. 138 (50%) and 136 (50%) patients were treated by PT and CT, respectively. The median follow-up time for all censored patients was 42.8 months (IQR 36.7 - 49.0). No grade 3 or severe treatment-related toxicity was observed. 3-year PFS was 81% (95% CI;76-86) and OS was 93% (95% CI;89-96), respectively. As to particle-ion type, 3-year PFS were 79.0% and 81.9% in PT and CT (p = 0.19), and 3-year OS were 93.9% and 91.1% in PT and CT (P = 0.72), respectively. For PFS, pathological confirmation, clinical stage was significant factors but there were no significant differences by tumor location or particle-ion type; for OS, clinical stage was significant factor but there was no significant difference on pathological confirmation, tumor location or particle-ion type (Table1). Table 1. 3-year PFS and OS CONCLUSION: Particle therapy for operable early-stage lung cancer resulted in excellent 3-year OS and PFS on each subset.

The Association between the Growth Pattern and Malignancy in the Formation of Ulceration in Gastric Gastrointestinal Stromal Tumor

Objective In general, surface ulceration in gastric gastrointestinal stromal tumor (GIST) is considered a malignant feature; however, the mechanism underlying its formation has not been evaluated in detail. In this study, we analyzed the factors involved in ulceration using resected specimens of gastric GIST. Methods A total of 48 samples were retrospectively analyzed. We examined the association of surface ulceration of gastric GIST with the MIB-1 labeling index, mitotic number, tumor size, endoscopic ultrasound (EUS) findings and growth pattern on computed tomography (CT). Results The proportion of men was significantly higher in the ulceration group than in the non-ulceration group (p=0.04146), whereas age was not significantly different between the groups. Tumor was significantly larger in the ulceration group than in the non-ulceration group (p=0.0048). There was no correlation between tumor size and ulcer number. The MIB-1 index was not related to ulceration, nor were EUS findings. The number of mitotic cells tended to be higher in the ulceration group than in the non-ulceration group (p=0.05988). Intraluminal growth pattern was strongly associated with ulceration (p=0.00019). After a multivariate analysis, the growth pattern was the only factor associated with ulceration of gastric GIST. Conclusion Although formation of surface ulceration in gastric GIST was partially associated with the degree of malignancy, the growth pattern was the most important factor associated with ulceration in gastric GIST.

Novel image enhancement technology that helps find bleeding points during endoscopic submucosal dissection of gastric neoplasms

BACKGROUND AND AIM

The management of bleeding during endoscopic submucosal dissection (ESD) is critical and related to the procedure time. We collaborated on a new image enhancement algorithm with parameter optimization for clinical use being developed by FUJIFILM Co. and processed white light image data offline to evaluate the effectiveness of this technology. This study aims to evaluate the clinical usefulness of this technology.

METHODS

Eighteen video scenes of bleeding points from five gastric ESDs were selected and processed by the new image enhancement algorithm. The time until a bleeding point was found, visibility of a bleeding point, and color abnormality of the submucosal layer were evaluated by ESD experts, ESD trainees, and endoscopy trainees. The color differences between the bleeding point and the surroundings in CIE-L*a*b* color space were calculated in the original and enhanced images.

RESULTS

The time until a bleeding point was found in the enhanced videos was significantly shorter than that in the original videos (11.10 s vs 13.85 s) (P = 0.017). On a 5-point (-2 to +2) Likert scale of visibility, the enhanced image was slightly superior to the original (+0.45), and the appearance of the submucosa was comparable between images (+0.14). The color difference among the bleeding areas on the enhanced images was significantly larger than that on the original images (10.93 vs 8.36).

CONCLUSION

This novel image enhancement algorithm emphasizes the color difference between a bleeding point and the surrounding area, which would help find bleeding points faster during ESD for the less experienced endoscopists.

Complete omission of second-look endoscopy after gastric endoscopic submucosal dissection in real-world practice

Gastric endoscopic submucosal dissection (ESD) is increasingly performed in patients receiving antithrombotic therapy. Second-look endoscopy (SLE) has been performed empirically in several clinical settings. We investigated whether SLE omission was associated with an increased risk of postESD bleeding in all patients, including those administered antithrombotic agents. Between July 2016 and June 2018, 229 patients were treated with a clinical pathway for gastric ESD that involved SLE on the day after ESD (SLE group). Between September 2018 and May 2020, 215 patients were treated using a clinical pathway that did not include SLE (nonSLE group). We retrospectively compared the incidence of postESD bleeding among the propensity score-matched cohorts and determined the risk factors for postESD bleeding using multivariate analysis. The propensity score-matched cohorts showed no significant differences in the incidence of postESD bleeding between the SLE (3.2%) and nonSLE (5.1%) groups. Multivariate analysis revealed that the presence of lesions in the lower gastric body (adjusted odds ratio [OR] 2.17, 95% confidence interval [CI] 1.06-4.35, P.03) was a significant risk factor for postESD bleeding during admission, whereas resected specimen size ≥ 40 mm (adjusted OR 3.21, 95% CI 1.19-8.19, P.02) and antiplatelet therapy (adjusted OR 4.16, 95% CI 1.47-11.80, P.007) were significant risk factors after discharge. Complete omission of SLE after gastric ESD does not increase postESD bleeding in clinical practice.

H. pylori negative gastric MALT lymphoma with API2-MALT1 translocation treated by endoscopic submucosal dissection: A case report

RATIONALE

API2-MALT1 positive gastric mucosa-associated lymphoid tissue (MALT) lymphomas are considered to have favorable prognosis. We report a case of API2-MALT1 positive gastric MALT lymphoma, treated by endoscopic submucosal dissection (ESD).

PATIENT CONCERNS

A 51-year-old man underwent esophagogastroduodenoscopy (EGD) for the annual health checkup examination.

DIAGNOSES

The EGD showed a reddish depressed lesion with small reddish spots in the lower gastric body. There was no endoscopic atrophy in the entire stomach and Helicobacter pylori (H. pylori) serum test was negative. Infiltration of small lymphocytes was shown in the gastric tissues obtained by the endoscopic biopsy. The fluorescence in situ hybridization using the biopsy samples confirmed the presence of genetic translocation of API2-MALT1, suggesting that the lesion is API2-MALT1 positive MALT lymphoma.

INTERVENTIONS

Since endoscopic ultrasound suggested that the lesion was localized within the lamina propria mucosae, we performed ESD to achieve the en bloc resection of the lesion.

OUTCOMES

Conclusive diagnosis of gastric MALT lymphoma was made based on the resected specimen. Lateral and vertical margins were negative. No lymphoma cells were detected using endoscopic biopsy after 5 years.

LESSONS

Our report suggests that ESD can be considered as alternative treatment for API2-MALT1 positive gastric MALT lymphoma if the lesion was localized within the gastric mucosa.

Comparative study of magnifying narrow-band imaging and conventional white light endoscopy in the diagnosis of Helicobacter pylori status after eradication therapy

Predicting Helicobacter pylori (Hp) status by endoscopic finding would be useful in recent clinical condition that the use of proton-pump inhibitors, anti-platelet, and anti-coagulant have become widespread. We aimed to elucidate the diagnostic accuracy of magnifying narrow-band imaging (M-NBI) endoscopy in distinguishing Hp status in patients with or without history of successful Hp eradication and compare this accuracy to the diagnostic accuracy of conventional white light (WL) endoscopy.Two hundred seven endoscopic examinations before and after Hp eradication were performed in prospective 163 patients. Endoscopic images by using the M-NBI and conventional WL were stored electronically and randomly allocated to 2 readers for evaluation. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were assessed by reference to Hp status assessed by conventional clinical test.Sensitivity, specificity, PPV, NPV, and accuracy for predicting Hp status for the conventional WL was 72.2%, 75.5%, 72.2%, 75.5%, and 73.9% for the first reader; 86.6%, 57.3%, 64.1%, 82.9%, and 71.0% for the second reader. On the other hand, sensitivity, specificity, PPV, NPV, and accuracy for predicting Hp status for the M-NBI was 96.9%, 93.6%, 93.1%, 97.1%, and 95.2% for the first reader; 92.8%, 93.6%, 92.8%, 93.6%, and 93.2% for the second reader, respectively. The diagnostic accuracy of M-NBI was significantly higher than that of WL (P < .0001 for both readers). Inter-observer agreement of M-NBI (k = 0.83) was also better than that of WL (k = 0.53).M-NBI was capable of distinguishing Hp status before and after eradication therapy.

Lower LINE-1 methylation is associated with promoter hypermethylation and distinct molecular features in gastric cancer

Aim: To investigate the associations between LINE1 methylation, an indicator for genome-wide hypomethylation, molecular and clinicopathological characteristics of gastric cancer (GC) patients. Patients & methods: LINE1 methylation statuses were examined in paired cancerous, non-neoplastic mucosa from 217 GC and gastric mucosa from separate group of 224 noncancer patients. CpG island methylator phenotype, TP53 and KRAS mutation, MLH1 methylation status and promoter hypermethylation of GC related and H. pylori-related genes were examined. Results: Lower LINE1 methylation was observed in primary GC compared with non-neoplastic gastric mucosa and associated with CpG island methylator phenotype, TP53 mutation, MLH1 methylation and promoter hypermethylation of GC related and H. pylori-related genes. Conclusion: Lower LINE1 methylation correlates specific molecular subtypes and promoter hypermethylation in GC.

Diagnostic utility of probe-based confocal laser endomicroscopy in superficial non-ampullary duodenal epithelial tumors

Background and study aims  Endoscopic diagnosis of superficial non-ampullary duodenal epithelial tumors (SNADETs) has not been established. Probe-based confocal laser endomicroscopy (pCLE: Cellvizio) provides real-time endomicroscopic analysis. We developed and validated a new pCLE classification of SNADET based on abnormal findings. Patients and methods  pCLE scanning of 20 SNADET lesions including 16 adenomas and four carcinomas was retrospectively evaluated to explore abnormal pCLE findings in relation to histological features. Diagnostic yield of pCLE findings was prospectively evaluated in an additional 20 SNADET lesions including 16 adenomas and four carcinomas. Results  In a retrospective study, we identified four abnormal pCLE findings of SNADETs: (1) dark epithelium, (2) columnar cells irregularly extending to the lumen, (3) distorted crypt structure, and (4) fluorescein leakage. Dark epithelium distinguished neoplastic lesions (adenomas and carcinomas) from non-neoplastic duodenal mucosa with a sensitivity of 90 % and a specificity of 100 %. Distorted crypt structure distinguished carcinomas from adenomas and non-neoplastic duodenal mucosa with a sensitivity of 100% and a specificity of 94 %. In the prospective study, the sensitivity and the specificity of the dark epithelium for the diagnosis of neoplastic lesions (adenomas + carcinomas) was 75% and 100 %. Sensitivity and the specificity of the distorted crypt structure for discrimination of carcinoma from adenoma were 100 % and 94 %, respectively. Conclusions  The pCLE findings correlated with the histopathology of the SNADETs. Dark epithelium and distorted crypt structure were informative pCLE findings to predict presence of neoplasia and cancer in the SNADET, respectively. UMIN-CTR UMIN000013857 TRIAL REGISTRATION: Single-Center, prospective observational trial UMIN000013857 at upload.umin.ac.jp.

Prostate Stem Cell Antigen Gene Polymorphism Is Associated with H. pylori-related Promoter DNA Methylation in Nonneoplastic Gastric Epithelium

Genome-wide association study identified two functional SNPs associated with gastric cancer especially the diffuse type. The first was a polymorphism (rs2294008) in prostate stem cell antigen (PSCA), and the other was a polymorphism (rs4072037) in mucin 1 (MUC1). DNA methylation is associated with gastric cancer and Helicobacter pylori (H. pylori)-induced gastritis, while hypermethylation of promoter CpG island (CGI) is a common characteristic of enlarged-fold gastritis induced by H. pylori, a risk factor of diffuse-type gastric cancer. We evaluated the association between PSCA and MUC1 polymorphisms with H. pylori--related promoter CGI methylation in the nonneoplastic gastric mucosa. PSCA rs2294008 C/T and MUC1 rs4072037 A/G polymorphisms were genotyped in 410 cancer-free subjects in relation to promoter CGI methylation status of three candidate genes, of which the methylation status is associated with H. pylori infection (IGF2, MYOD1, and SLC16A12). Methylation levels of all three genes were significantly higher in subjects with PSCA rs2294008 T/T compared with the PSCA rs2294008 C/C (all P < 0.05). Such associations were more enhanced in H. pylori-positive subjects (all P < 0.01). The multivariate analysis demonstrated that PSCA C/T [OR, 2.37; 95% CI (confidence interval), 1.06-5.29; P = 0.035] and T/T genotypes (OR, 3.2; 95% CI, 1.41-7.25; P = 0.005) were significantly associated with methylation-high gastric mucosa as independent factors. MUC1 rs4072037 A/G polymorphism was not associated with methylation status of all three genes. PSCA C/T and T/T genotypes are associated with H. pylori-related promoter DNA methylation in the gastric mucosa.Impact: Our observations provided the evidence that PSCA polymorphism influence the susceptibility to gastric cancer through DNA methylation induction.

Molecular subtyping of gastric cancer combining genetic and epigenetic anomalies provides distinct clinicopathological features and prognostic impacts

Both genetic and epigenetic abnormalities play important roles in gastric cancer (GC) development. We investigated whether the molecular subtypes of gastric cancer by combining genetic and epigenetic anomalies define its clinicopathological features and prognosis. The CpG island methylator phenotype (CIMP), MLH1 methylation, TP53, and KRAS mutation statuses were characterized in 214 GCs in relation to their clinicopathological features and prognosis. The molecular subtypes based on CIMP and TP53 hot spot mutation status (R175, G245, R248, R273, and R282) best predicted prognosis of GC. These subtypes contained 120 CIMP-positive (CIMP+) TP53 hot spot mutation-negative (TP53 hot spot-) cases, 81 CIMP-negative (CIMP-) TP53 hot spot- cases, 8 CIMP+TP53 hot spot mutation-positive (TP53 hot spot+) cases, and 5 CIMP- TP53 hot spot+ cases. The CIMP-TP53 hot spot+ group presented the worst overall survival (OS) and progression-free survival (PFS), followed by the CIMP+TP53 hot spot+, CIMP-TP53 hot spot- and CIMP+TP53 hot spot- groups (both P < 0.0001). These subtypes also correlated well with several aggressive clinicopathological features in that order. The molecular subtypes were independent factors for predicting overall survival (hazard ratio = 1.66, 95% CI = 1.07-2.57, P = 0.006). The molecular subtypes combining the CIMP and TP53 hot spot mutation status provide distinct clinicopathological features and prognostic impacts in GC.

In vivo diagnosis of early-stage gastric cancer found after Helicobacter pylori eradication using probe-based confocal laser endomicroscopy

BACKGROUND AND AIM

Early-stage gastric cancer (EGC) found after Helicobacter pylori (Hp) eradication often displays non-tumorous regenerative epithelium and/or maturated tumorous epithelium overlying the cancerous tissue, which may confuse endoscopic and histological diagnosis. Probe-based confocal laser endomicroscopy (pCLE) enables in vivo real-time optical biopsy. We compared the diagnostic yields for these EGC cases using conventional white light endoscopy (WL), magnifying endoscopy with narrow-band imaging (ME-NBI), pCLE, and endoscopic biopsy; we also compared the accuracy of the horizontal extent diagnosis between ME-NBI and pCLE.

METHODS

This study enrolled 30 patients with 36 EGC lesions after successful Hp eradication. Diagnostic yields of WL, ME-NBI, pCLE, and endoscopic biopsy were prospectively compared. Four points of cancerous margins (oral, anal, anterior, and posterior sites) were also prospectively evaluated with M-NBI and pCLE to determine the horizontal extent of the EGC.

RESULTS

Diagnostic yield was significantly higher with pCLE than with WL and endoscopic biopsy (97 vs 72%, 97 vs 72%, P = 0.0159, 0.0077, respectively), whereas it did not differ from ME-NBI (88.9%, P = 0.371). Height of non-tumorous regenerative epithelium or maturated atypical glands was 104.7 ± 34.2 μm in the pCLE-positive cases, whereas it was 188.3 ± 27.1 μm in a pCLE-negative case (P = 0.0004). Diagnostic accuracy of the horizontal margin of EGC was significantly higher with pCLE than with ME-NBI (92 vs 70%, P = 0.0159).

CONCLUSION

pCLE may be helpful for the diagnosis of ambiguous ECG found after Hp eradication because it enables real-time scanning throughout the lesion and detection of subsurface microstructure.

Endoscopic features of lymphoid follicles using blue laser imaging (BLI) endoscopy in the colorectum and its association with chronic bowel symptoms

Background/Aim

In the colorectum, lymphoid follicles hyperplasia (LH) is sometimes observed as small, round, yellowish-white nodules. The novel image-enhanced endoscopy system named blue laser imaging (BLI) provides enhanced the contrast of surface vessels using lasers for light illumination. We investigated the endoscopic features of LH observed by using BLI endoscopy and its association with chronic bowel symptoms.

Patients/Methods

300 participants undergoing colonoscopy for various indications were enrolled. Entire colorectum was observed by using BLI-bright mode with non-magnification view. LH was defined as well demarcated white nodules. Elevated LH with erythema was distinguished as LH severe.

Results

LHs were observed more clearly by using BLI-bright mode compared to conventional white light colonoscopy and were also histologically confirmed as intense infiltration of lymphocytes or plasmacytes. LH was observed in 134 subjects (44.6%) and 67 (22.3%) were LH severe. LH was associated younger age (Odds ratio (OR) = 1.05, 95%Confidence Interval (95%CI) = 1.03–1.07, P<0.0001) and chronic bowel symptoms including constipation, hard stools, diarrhea and loose stools (all LH: OR = 4.03, 95%CI = 2.36–6.89, P<0.0001, LH severe: OR = 5.31, 95%CI = 2.64–10.71, P<0.0001). LH severe was closely associated with both constipation associated symptoms (OR = 3.94, 95%CI = 1.79–8.66, P = 0.0007) and diarrhea associated symptoms (OR = 5.22, 95%CI = 2.09–13.05, P = 0.0004). In particular, LH severe in the ascending colon was strongly associated with bowel symptoms (P<0.0001).

Conclusion

LH, visualized by using BLI endoscopy was associated with bowel symptom, raising the possibility of pathogenic role of this endoscopic finding in the functional lower gastrointestinal disorders.

Usefulness of confocal laser endomicroscopy to diagnose ulcerative colitis-associated neoplasia

Chromoendoscopy, narrow-band imaging (NBI), and confocal laser endomicroscopy (CLE) have been introduced in ulcerative colitis (UC)-associated neoplasia surveillance. We aimed to determine the ability of CLE to differentiate among UC-associated neoplasia (differentiated type or undifferentiated type), sporadic adenoma, and circumscribed regenerative lesions. Of 665 patients with UC, we carried out probe-based CLE (pCLE) on 12 patients with suspected UC-associated neoplasia in addition to magnifying chromoendoscopy with crystal violet and NBI. We compared pCLE findings with pathological diagnoses. pCLE could differentiate UC-associated differentiated cancer from other pathologies such as solitary adenoma and non-neoplastic circumscribed regenerative lesions on the basis of back-to-back orientation of crypts (P = 0.048), and UC-associated undifferentiated cancer from other pathologies on the basis of dark trabecular architecture (P = 0.015). Sensitivity, specificity, and accuracy of combination of back-to-back orientation of crypts and dark trabecular architecture for carcinoma or dysplasia were 100%, 83%, and 92%, respectively. In vivo microscopic observation with pCLE was helpful to evaluate the suspected UC-associated neoplasia.

Potential link between Fusobacterium enrichment and DNA methylation accumulation in the inflammatory colonic mucosa in ulcerative colitis

BACKGROUND AND AIM

Fusobacterium enrichment has been associated with colorectal cancer development. Ulcerative colitis (UC) associated tumorigenesis is characterized as high degree of methylation accumulation through continuous colonic inflammation. The aim of this study was to investigate a potential link between Fusobacterium enrichment and DNA methylation accumulation in the inflammatory colonic mucosa in UC.

METHODS

In the candidate analysis, inflamed colonic mucosa from 86 UC patients were characterized the methylation status of colorectal a panel of cancer related 24 genes. In the genome-wide analysis, an Infinium HumanMethylation450 BeadChip array was utilized to characterize the methylation status of >450,000 CpG sites for fourteen UC patients. Results were correlated with Fusobacterium status.

RESULTS

UC with Fusobacterium enrichment (FB-high) was characterized as high degree of type C (for cancer-specific) methylation compared to other (FB-low/neg) samples (P<0.01). Genes hypermethylated in FB-high samples included well-known type C genes in colorectal cancer, such as MINT2 and 31, P16 and NEUROG1. Multivariate analysis demonstrated that the FB high status held an increased likelihood for methylation high as an independent factor (odds ratio: 16.18, 95% confidence interval: 1.94-135.2, P=0.01). Genome-wide methylation analysis demonstrated a unique methylome signature of FB-high cases irrespective of promoter, outside promoter, CpG and non-CpG sites. Group of promoter CpG sites that were exclusively hypermethylated in FB-high cases significantly codified the genes related to the catalytic activity (P=0.039).

CONCLUSION

Our findings suggest that Fusobacterium accelerates DNA methylation in specific groups of genes in the inflammatory colonic mucosa in UC.

Histological evaluations of primary lesions are independently associated with prognosis in patients with gastric cancer who receive neoadjuvant chemotherapy

Neoadjuvant chemotherapy may improve outcomes for patients with locally advanced gastric cancer (GC). To explore useful predictive factors for the response of advanced GC to neoadjuvant chemotherapy, tumor responses were assessed using computed tomography (CT) with histological based criteria. A total of 78 patients with advanced GC undergoing neoadjuvant chemotherapy were included. CT-based response assessment was performed following 2 courses of treatment. Histological evaluation of resected specimens was also performed according to the Japanese classification of gastric carcinoma. Grade 1b, 2 and 3 (viable tumor cells remaining in <2/3 of the tumorous area) were defined as histological responders. The results were associated with overall survival (OS) and progression-free survival (PFS). The majority of the cases underwent tegafur/gimeracil/oteracil based preoperative chemotherapy as the first line of treatment (n=76, 96%). A total of 25 (32%) and 29 (37%) cases were considered to be CT and histological responders, respectively. CT-based evaluation was not associated with OS or PFS, while histological evaluation was significantly associated with OS and PFS. Histological based evaluation was not associated with CT and GI X-ray or endoscopy-based evaluation of primary lesions. Multivariate survival analysis using Cox's regression model demonstrated that histological non-response was an independent prognostic factor for predicting worse OS. Histological-based evaluation of primary lesions was independently associated with prognosis in patients with GC who underwent neoadjuvant chemotherapy.

Evaluations of primary lesions by endoscopy clearly distinguishes prognosis in patients with gastric cancer who receive chemotherapy

Background

Chemotherapy may improve outcomes in gastric cancer (GC), especially for the patients with advanced stage. To explore useful predictive factor for GC performing chemotherapy, we compared the tumor responses assessed using computed tomography (CT) with endoscopy based criteria.

Methods

192 GC patients performing chemotherapy were retrospectively studied. CT based response assessment was performed after 2 courses of treatment. Endoscopic evaluation according to The Japanese classification of gastric carcinoma was also performed at same period. Data were correlated with overall survival (OS) and progression-free survival (PFS).

Results

Majority of the cases (n = 178, 93%) received S-1 based chemotherapy as the first line treatment. 55 (29%) and 91 (47%) cases were considered to be CT and endoscopic responders. Endoscopic responder was more clearly associated with better OS and PFS compared to CT based responder by the log-rank test (P<0.0001 vs. 0.01 and P<0.0001 vs. 0.008, respectively). The association was more striking among patients performing neoadjuvant chemotherapy (P<0.0001 vs. 0.15 and P<0.0001 vs. 0.1, respectively). Multivariate survival analysis using Cox's regression model revealed that endoscopic non-responder was the independent predictive factor, being more strongly associated with worse OS when compared to CT non-responder (hazard ratio: 4.60 vs. 1.77, 95% confidence interval: 2.83–7.49 vs.1.08–2.89, P<0.0001 vs. 0.02). More advanced T, N stage and cases who had peritoneal dissemination were significantly associated with endoscopic non-responder (all P values <0.01).

Conclusion

Endoscopy based evaluation of primary lesions are clearly associated with prognosis in patients with GC who perform chemotherapy.

Usefulness of Pseudocontinuous Arterial Spin-Labeling for the Assessment of Patients with Head and Neck Squamous Cell Carcinoma by Measuring Tumor Blood Flow in the Pretreatment and Early Treatment Period

BACKGROUND AND PURPOSE

For the assessment of the treatment response in non-surgical treatment, tumor blood flow provides the functional information of the tumor which is different from the morphological information such as tumor volume. The purpose of this study was to evaluate the diagnostic value of tumor blood flow values obtained by pseudocontinuous arterial spin-labeling in patients with head and neck squamous cell carcinoma.

MATERIALS AND METHODS

Forty-one patients with head and neck squamous cell carcinoma were evaluated by using pseudocontinuous arterial spin-labeling. Quantitative tumor blood flow was calculated at the pretreatment and the early treatment periods in all the patients, and the percentage change of tumor blood flow between the two was calculated. At the early treatment period, based on their tumor volume reduction rate, we divided the patients into stable disease and partial response groups for a subgroup analysis. The local control or failure was confirmed either by histopathology or by radiologic evaluation within the follow-up.

RESULTS

Pretreatment tumor blood flow in patients in the failure group was significantly lower than that in patients in the local control group. In the subgroup analysis of patients with stable disease, the percentage change of tumor blood flow was significantly larger (due to the tumor blood flow increase from pretreatment value) in the local control group than in the failure group. In addition, in patients with a partial response, the percentage change of tumor blood flow was significantly smaller (due to the tumor blood flow decrease from the pretreatment value) in the local control group than in the failure group. The accuracy for determination of the local control group or the failure group in pretreatment tumor blood flow was 0.83 and that in the combination use of the percentage change of tumor blood flow and tumor volume in the early treatment period was 0.93.

CONCLUSIONS

Tumor blood flow obtained by pseudocontinuous arterial spin-labeling can be useful for the determination of local control. The combined use of the percentage change of tumor blood flow and tumor volume had particularly high diagnostic accuracy.

Novel approach to analysis of in vitro tumor angiogenesis with a variable-pressure scanning electron microscope: suppression by matrix metalloproteinase inhibitor SI-27

Degradation of basement membrane by metalloproteinases (MMP) is a critical step in tumor angiogenesis. To evaluate in vitro angiogenesis, several models have been employed, including bovine cornea, fenestrated rat brain, Matrigel, and others. These models did not provide quantitative analysis of capillary formation. The current study aimed for a novel approach to in vitro assay of angiogenesis with a "wet scanning electron microscope (SEM)" to investigate suppression of tumor angiogenesis by the MMP inhibitor, SI-27. The effects of noncytotoxic concentrations of SI-27 (1-100 microM) were determined on nonmitogenic vascular endothelial growth factor (VEGF) (10 ng/ml)-mediated cell motility and in vitro angiogenesis of human umbilical vein endothelial cells (HUVECs). Activities of MMP and tissue inhibitor of metalloproteinase (TIMP) were determined by enzyme-linked immunosorbent assay (ELISA). Subsequently, the inhibitory effect of SI-27 was examined on in vitro angiogenesis stimulated by supernatants of human glioma cell lines (U87MG, U251MG, or U373MG). In vitro angiogenesis was quantitatively analyzed with a variable-pressure SEM. Cell motility and in vitro angiogenesis by HUVECs were significantly increased by VEGF along with elevated MMP-1 and -2 activity, whereas SI-27 significantly suppressed VEGF-mediated in vitro angiogenesis and inactivated both MMP-1 and MMP-2, but not inhibited cell motility. The angiogenesis promoted by glioma supernatants showed a significant reduction in the presence of SI-27. SI-27, a novel MMP inhibitor, inhibited tumor angiogenesis in vitro. It can be anticipated to prevent tumor growth through its angiosuppressive effect. Quantitative analysis with a variable-pressure SEM is a novel approach to in vitro angiogenesis assay.

Signalling pathway mediated by CXCR7, an alternative chemokine receptor for stromal-cell derived factor-1α, in AtT20 mouse adrenocorticotrophic hormone-secreting pituitary adenoma cells

Stromal cell-derived factor (SDF)-1 and its receptor, CXCR4, have been identified in both neurones and glia of many brain areas. Previous studies have mainly focused on the role of SDF-1 and CXCR4 in modulating the hypothalamic-pituitary axis and their possible involvement in the development of pituitary adenomas. An alternative SDF-1 receptor, CXCR7, has recently been identified, but it has not been studied in the context of pituitary adenomas. The present study aimed to investigate the distribution and function of CXCR7 in pituitary adenomas. The expression of CXCR7, normalised to β-actin, was assessed by tissue microarray analysis of 62 adenomas, including 23 growth hormone (GH)-producing adenomas, 22 nonfunctioning adenomas, seven prolactin (PRL)-producing adenomas, six adrenocorticotrophic hormone-producing adenomas and four thyroid-stimulating hormone-producing adenomas. In vitro functional studies used RNA interference (RNAi) and cDNA microarray analysis to evaluate the CXCR7 signalling pathway in AtT-20 mouse pituitary adenoma cells treated with recombinant mouse SDF-1α and transfected with RNAi against Cxcr7 or control RNAi. In tissue microarray analysis, prominent expression of CXCR7 was observed in GH-producing adenomas and PRL-producing adenomas, and in macroadenomas (P < 0.05). Intracellular signalling via CXCR7 up-regulated Bub1, Cdc29 and Ccnb1, and down-regulated Asns, Gpt, Pycr1, Cars and Dars. The present study demonstrates that the SDF-1α ⁄ CXCR7 signalling pathway regulates genes involved in cell cycle control, amino acid metabolism and ligase activity, which comprise targets that are distinct from those of CXCR4.

Effectiveness of endoscopic surgery training for medical students using a virtual reality simulator versus a box trainer: a randomized controlled trial

BACKGROUND

The first step toward increasing the level of patient safety in endoscopic surgery is for all endoscopic surgeons to acquire fundamental skills, including psychomotor skills, in the preoperation stage of training. The current study aimed to evaluate the effectiveness of virtual reality (VR) simulator training and box training for training the fundamental skills of endoscopic surgery.

METHODS

For this study, 35 medical students at Kyushu University were divided into three groups: simulator (SIM) group (n = 20), box trainer (BOX) group (n = 20), and control group (n = 15). None of the students had any experience assisting with endoscopic surgery or any previous training for endoscopic surgery. The students in the SIM group underwent training using a VR simulator, the Procedicus MIST, 2 h per day for 2 days. The students in the BOX group underwent training using a box trainer 2 h per day for 2 days. The students in the control group watched an educational video for 30 min. The endoscopic surgical skills of all the students were evaluated before and after training with a task of suturing and knot tying using a box trainer.

RESULTS

Although no significant differences were found between the three groups in the total time taken to complete the evaluation task before training, there were significant improvements in the SIM and BOX groups after training compared with the control group. Box training increased errors during the task, but simulator training did not.

CONCLUSION

The findings showed that box training and VR training have different outcomes. The authors expect that the best curriculum for their training center would involve a combination that uses the merits of both methods.

Decompression surgery and intraoperative radiation therapy (IORT) for metastatic spinal tumors

20515

Background: Metastatic spinal tumors often cause spinal cord compression and jeopardize the quality of life of the patients much. To decrease the local symptomatic recurrence rate, we have been adding IORT to decompression surgery. Methods: For those patients whose life expectancy was more than 6 months were eligible for this treatment. Posterior decompression by laminectomy of the involved vertebrae was performed. Following decompression, the patient was irradiated the lesions intraoperatively with electrons generated from Microtron by shielding the spinal cord with lead plate. The central aspects of the vertebrae were irradiated by scattered electrons detouring from the edge of the lead shield up to 40% of the administered dose. Following IORT, posterior instrumentation was performed. External beam radiotherapy might be added pre- and/or postoperatively when considered necessary. Results: 108 patients were treated between 1992–2005. There were 58 males and 50 females. Age ranged from 26 to 85 with a median of 62.5. By primary sites, 26 breast, 24 kidney, 18 colorectum, 17 lung 12 prostate and 11 thyroid cases were included. Irradiated spines were cervical in 6, thoracic in 76, and lumbar/sacral in 27. Overall median follow-up period was 12.7months. Median IORT dose was 20Gy (range 15–26Gy) and median electron energy was 16MeV (range 11–22MeV). There were 37 cases with preoperative RT and 41 cases with postoperative RT. Overall median survival time was 14.5months (breast 15.3, kidney 22.6, colorectum 5.7, lung 6.2, prostate 31.6, thyroid 60.6months). Neurological response rate was 73.1%. Ambulatory rates were 87.0% for success and 80.6% for rescue by Klimo's definition(2005). There were only 8 symptomatic relapses (7%). As for major complications, only one myelopathy has been observed. Conclusions: Decompression surgery and IORT for metastatic spinal tumors with impending spinal cord compression was a promising treatment modality with excellent local control and neurological response rate and with minimal toxicity especially for those patients with long-term prognosis.

No significant financial relationships to disclose.

Development and assessment of morphologic criteria for diagnosing gastric cancer using confocal endomicroscopy: an ex vivo and in vivo study

BACKGROUND AND STUDY AIMS

The Confocal Endomicroscopy System (Optiscan Pty Ltd. and Pentax Corp.) is a newly developed imaging tool that uses laser light and optical technology to visualize living tissue at the cellular level. Digital images of cells magnified 1000-fold appear in real time on a computer screen, which enables immediate detection of changes in cellular structure without the need for a biopsy. The aim of this study was to assess the features of the cellular architecture of cancerous tissue that can be used in the differential diagnosis of cancerous tissue and normal mucosa using this system's image-processing software.

PATIENTS AND METHODS

A total of 27 gastric cancers were examined ex vivo using confocal endomicroscopy. A fluorescent contrast agent, acriflavine, was applied topically to normal and to cancerous mucosa. In vivo imaging of the gastric mucosa after intravenous injection of fluorescein sodium was also performed in nine patients with gastritis or gastric cancer.

RESULTS

The nuclear area in the ex vivo specimens was calculated using Scion Image software. The mean nuclear area of cancer cells was found to be significantly larger than that of normal cells in 18/27 gastric cancers (67 %). The mean nuclear area of the cancers tended to be larger than that of normal mucosa, especially in cases of differentiated adenocarcinoma. In more than half the cases, it was possible to diagnose malignancy automatically using confocal endomicroscopy and image-processing software without the need for biopsy and pathological examination. In vivo imaging of cancerous lesions showed irregularity in cellularity and vascularity.

CONCLUSION

The ability of this imaging device to differentiate between normal tissue and cancerous tissues gives it potential value as a new screening tool for early detection of malignancy.

A case of pleomorphic xanthoastrocytoma presenting with massive tumoral hemorrhage

Pleomorphic xanthoastrocytoma has been generally conceived to be in a benign nature, showing a relatively favorable prognosis. Apoplectic attack attributable by massive hemorrhage in this distinct form of the supratentorial glioma is an exceedingly rare event. A 61-year-old female presented with a sudden onset of generalized tonic--clonic convulsion. CT and MRI disclosed the presence of a tumor composing of massive intra-tumoral hemorrhage filling the cyst associated with mural nodule in the left frontotemporal lobe. At surgery, the subpial mass involving hematoma was well marginated and slightly adherent to the dura mater. It could be removed totally and proved to be a pleomorphic xanthoastrocytoma. The unusual hemorrhagic presentation of this typically benign entity is extremely rare and is thought to be intra-tumoral bleeding in this case, since subarachnoid hemorrhage was absent.

Induction of apoptosis by estramustine phosphate mediated by phosphorylation of bcl-2

Estramustine phosphate (EMP) is an anti-microtubule agent that induces apoptosis of glioma cells. We investigated whether EMP caused apoptosis through the alkylating effect of its nitrogen mustard component or by phosphorylation of bcl-2 like other anti-microtubule agents in normal human astrocyte and human malignant glioma cell lines. Apoptosis was seen in glioma cells treated either with nitrogen mustard or EMP and expression of bcl-2 mRNA was not changed by exposure to the drug. An immunoprecipitation study only found phosphorylation bcl-2 in glioma cells exposed to EMP and not in cells exposed to nitrogen mustard. These results indicate that induction of apoptosis in glioma cells by EMP is mediated by phosphorylation of bcl-2.

Suppression of matrix metalloproteinase-2 and -9 mediated invasiveness by a novel matrix metalloproteinase inhibitor, BE16627B

Cell invasion is a nature of malignant gliomas, demeriting to many efforts of the treatment. Matrix metalloproteinase (MMP) is acknowledged as a key factor in this complicated process. The aim of this study was to investigate whether inhibition of MMP activity in malignant glioma cells could be achieved by a novel agent, BE16627B (BE). Malignant glioma cell lines, U87MG, U251MG, and U373MG, were employed to evaluate inhibitory effect on zymogram, type IV collagenolysis assay, and haptoinvasion assay for 24 h exposure of BE, following preliminar

Evaluation of hepatocellular carcinoma after treatment with transcatheter arterial chemoembolization: comparison of Lipiodol-CT, power Doppler sonography, and dynamic MRI

BACKGROUND

The purpose of this study was to compare the ability of Lipiodol-computed tomography (CT), power Doppler (PD) sonography, and dynamic magnetic resonance imaging (MRI) in evaluating the therapeutic effect of transcatheter arterial chemoembolization (TACE) on hepatocellular carcinoma (HCC).

METHODS

TACE was performed by injecting an emulsion consisting of Lipiodol and a chemotherapeutic drug, followed by gelatin sponge particles, into 54 patients with 84 HCC lesions. Five to 7 days later, Lipiodol-CT, PD sonography, and dynamic MRI were performed. Findings from the three modalities were correlated with relapse within 1 year after TACE.

RESULTS

All lesions with blood flow on PD sonography or intratumoral enhancement on dynamic MRI relapsed regardless of the findings with Lipiodol-CT. None of the negatively enhanced lesions on dynamic MRI relapsed regardless of the Lipiodol-CT findings. However, the readers could not evaluate the contrast uptake in 14 lesions that were already hyperintense on the precontrast images. These cases were considered unsuitable for qualitative assessment and reduced the applicability of MRI to 83% of the examined lesions (70 of 84). Although PD sonography perfectly predicted relapse in superficial (0-5 cm from abdominal surface) lesions of the right hepatic lobe, blood flow in deep (>5 cm) or left lobe lesions was undetectable regardless of the occurrence of relapse. As a result, Lipiodol-CT displayed 76.0% sensitivity, 67.6% specificity, and 72.6% accuracy. The sensitivity, specificity, and accuracy of PD sonography were 34.0%, 100%, and 60.7%, respectively. In the 70 lesions in which evaluation was possible, dynamic MRI achieved 100% sensitivity, 100% specificity, and 100% accuracy.

CONCLUSION

Of the three modalities, dynamic MRI was the best for evaluating the efficacy of TACE in the treatment of HCC. We also found that superficial lesions of the right lobe are good candidates for PD sonography. However, high signals on precontrast MR images, motion artifacts, and ultrasonic attenuation remain key limitations.

Chronological analysis of physiological T2* signal change in the cerebrum during breath holding

The purpose of this study was to examine which physiological factors affect cerebral T2* signal intensity (SI) during breath holding (BH) (apnea after inspiration and breathing after expiration) in normal volunteers. We examined SI changes caused by anoxic gas inhalation, by respiratory movements, and by BH. High-speed echo planar images (EPI) showed changes in SI that could be divided into five phases. Reports indicate that SI changes induced by BH are due to the effects on the magnetic susceptibility of deoxygenated hemoglobin (deoxyhemoglobin (dHb)) and to hypercapnia, but these reports could not fully explain the observed five phases. In addition to deoxyhemoglobin susceptibility and hypercapnia, we found that respiratory movements play a third critical role in modifying SI by affecting blood flow into the region of interest (ROI), as judged from right carotid artery flow. Consequently, we propose that the physiological SI changes induced by BH are derived from blood oxygenation, hypercapnia, and respiratory movements.

The bleb formation of the extracellular pseudopodia; early evidence of microtubule depolymerization by estramustine phosphate in glioma cell; in vitro study

Estramustine phosphate (EMP) is an anti-microtubule agent that depolymerizes microtubules and also causes apoptosis of glioma cells. Both of these pharmacological actions have been previously studied within the same cytotoxic range of EMP concentrations. The purpose of this study was to investigate which of these two phenomena occurred before the other. A preliminary MTT assay was done to distinguish non-cytotoxic (0.005-0.1 microM) and cytotoxic (0.5-10 microM) of EMP for BT4C cells. To investigate apoptotic changes, transmission electron microscopy (TEM), DNA laddering, and in situ endo-labeling (TUNEL) method were employed. A chemotaxis assay was used to assess cell motility. Scanning electron microscopy and TEM immunocytochemistry with an anti-beta tubulin antibody were applied to detect morphological changes of the microtubules. Suppression of cell motility by cytotoxic doses of EMP (0.5-10 microM) group was attributed by the cyto-reductive effect, relating to apoptosis. At 0.01-0.1 microM (non-cytotoxic doses), EMP did not indue apoptosis. At these concentrations, TEM and immunohistochemistry revealed the formation of blebs on the tip of the pseudopodia that contained abnormally depolymerized microtubules, a finding that was not observed at a low temperature or during cell migration. Cell chemotaxis was significantly inhibited by cytostatic EMP doses (0.05 and 0.1 microM). Bleb formation of the pseudopodia might be evidence of the abnormal disassembly of microtubules by cytostatic EMP concentrations, prior to the induction of apoptosis. In glioma cells EMP probably initiates apoptosis by causing the depolymerization of microtubules. Inhibition of cell motility by cytostatic doses of EMP could be beneficial to support other therapies.

Suppression of cell invasion on human malignant glioma cell lines by a novel matrix-metalloproteinase inhibitor SI-27: in vitro study

Matrix metalloproteinase (MMP) has come to be highlighted by its close relation to the cell invasion of gliomas. Suppression of MMP activity in malignant glioma cells would be meriting to local delivery of genes or chemotherapeutic agents. In this study, we employed a novel MMP inhibitor, SI-27 to investigate inhibition of cell invasiveness in human malignant glioma cell lines, U87MG, U251MG, and U373MG. We evaluated with zymogram, reverse zymogram, and cell invasion assay after exposure of SI-27 for 24 h followed by preliminary MTT assay to find non-cytotoxic dose range, 5, 10, 50, 100 microg/ml compared with non-treatment group as the control. Common to three glioma cell lines, zymogram disclosed that expressions of MMP-2 and -9 were suppressed in a dose-dependent fashion, meanwhile those of tissue inhibitor of MMP (TIMMP) in reverse zymogram were not. The numbers of invading cells through Boyden chamber were significantly reduced in a dose-dependent manner, while those with 5 microg/ml were not diminished common to those three lines. In conclusion, dose concentration ranging 10-100 microg/ml of SI-27 inhibited MMP-2 and -9 mediated cell invasiveness in malignant glioma cell lines. This is the first report for chemotherapeutic effect of SI-27 on glioma cells.

Drug-induced apoptosis by anti-microtubule agent, estramustine phosphate on human malignant glioma cell line, U87MG; in vitro study

The drug effect of estramustine phosphate (EMP), an anti-microtubule agent on human glioma cells has been studied with the focus being mainly its cytotoxity or its targeting of organelles. However, the pharmacological knowledge of estramustine with respect to its cytotoxity and mechanism is limited. To acquire such knowledge, the present study investigates the ability of EMP to induce apoptosis in a human malignant glioma cell line. Transmission electron microscope (TEM) images were examined to monitor periodic changes. Agarose gel electrophoresis was also examined. Cellular DNA fragmentation ELISA was performed to investigate the DNA fragmentation rates and an MTT assay was studied to evaluate the ID50. A TEM study revealed condensing and fragmentation of the chromatin. Laddering of the bands was observed in all EMP exposure groups in agarose gel electrophoresis. DNA fragmentation in all EMP groups began at 0.5 h following an exposure with EMP and increased in a dose- and time-dependent manner as revealed by DNA ELISA fragmentation. ID50 at 24 h was 5.0 microM according to the MTT assay, a value close to 4.8 microM of ID50 was revealed by the DNA fragmentation assay. None of the above mentioned changes was observed in the control group. These results indicated that EMP caused a drug-induced apoptosis in the human malignant glioma cell line, U87MG.

Intracranial malignant meningioma with abdominal metastases associated with hypoglycemic shock: a case report

A thirty-year-old male with an intracranial malignant meningioma, first diagnosed 9 years ago, with three recurrences was admitted with a hypoglycemic shock. The blood glucose level was 17 mg/dl, requiring treatment with high doses of intravenous and oral dextrose for improvement. A large metastatic tumor in the liver was noted. All hormones and peptides influencing blood glucose levels were in their normal levels. Chemo-embolization and injection of anti-cancer drugs was employed in the management of the metastatic tumor. Positron emission tomography was performed to measure the glucose metabolism of the abdominal tumor and it indicated that glucose consumption within the tumor was much elevated than the surrounding abdominal organs. Hypoglycemia secondary to primary hepatoma or islet-cell cancer has been frequently described, but a complication of metastatic meningioma is an exceedingly rare event. Elevated glucose consumption within the tumor might be addressed as one of the reasons for hypoglycemia, not due to the elevated serum levels of insulin or IGF, but due to the closely related blood glucose level.

Evaluation of the intratumoral vasculature of hepatocellular carcinoma by power doppler sonography: advantages and disadvantages versus conventional color doppler sonography

BACKGROUND

To determine whether a difference exists in the relative ability of power Doppler sonography and conventional color Doppler sonography to detect the intratumoral vasculature of hepatocellular carcinoma based on lesion size and location.

METHODS

Sixty patients with 88 hepatocellular carcinoma lesions that showed tumor staining on angiography and were enhanced on dynamic computed tomography were evaluated. Power Doppler sonography and color Doppler sonography were used to detect the intratumoral vasculature, and their sensitivity to blood flow was evaluated.

RESULTS

Power Doppler sonography showed a superior detection rate for lesions smaller than 2 cm and located 4-8 cm from the abdominal surface in the right hepatic lobe as compared with color Doppler sonography (p < 0.01). Neither power Doppler sonography nor color Doppler sonography depicted the intratumoral vasculature of lesions located more than 8 cm from the abdominal surface (n = 14). Both color Doppler imagings exhibited a low detection rate for lesions in the left hepatic lobe (n = 31, p < 0.01).

CONCLUSIONS

Power Doppler sonography should be applied in the evaluation of small or intermediate depth lesions because it is more sensitive to these lesions than color Doppler sonography, but it is not useful for left lobe and deep lesions.

[Preliminary study of calculating cerebral arterial blood oxygen saturation using MRI]

To assess whether cerebral arterial blood oxygen saturation (SaO2) can be calculated by EPI, we examined the relationship between peripheral SaO2 and T2+ signal intensity (SI) changes in the brain in three normal subjects, using 1.5 Tesla MRI. To decrease SaO2, hypoxia was induced by 100% helium-gas inhalation (60 sec). SI declined as SaO2 decreased during helium inhalation, while rapid recovery of SI to the baseline was noted with recovery from hypoxia. The differential effective transverse relaxation rate was closely correlated with SaO2 (r > 0.94). Consequently, using MRI, we were able to calculate arterial SaO2.

Scintigraphic prediction of resistance to radiation and chemotherapy in patients with lung carcinoma: technetium 99m-tetrofosmin and thallium-201 dual single photon emission computed tomography study

BACKGROUND

Various prognostic markers for lung carcinoma have been proposed, but to the authors' knowledge none is noninvasive and convenient for clinical use. The current study examined the utility of several radiotracers for the prediction of multidrug resistance (MDR) and radioresistance in patients with lung carcinoma.

METHODS

Thirty patients with untreated lung carcinoma underwent a dual isotope single photon emission computed tomography (SPECT) scan at 10 minutes and 120 minutes after the injection of technetium-99m ((99m)Tc)-tetrofosmin ((99m)Tc-TF) (370 megabecquerels [MBq]) and thallium-201 ((201)TlCl) (111 MBq). Retention of each tracer was evaluated semiquantitatively. Using radiation and chemotherapy (cisplatin plus etoposide), the patients either were treated sequentially (n = 12) or concurrently (n = 18). The relation between therapeutic response and retention of each tracer was analyzed. The detectability of radioresistance was examined.

RESULTS

In patients treated with sequential therapy, the response to radiation was predicted by (99m)Tc-TF retention, whereas (201)Tl retention was found not to be predictive. Regardless of whether the sequential or concurrent protocol was applied, 14 of 18 tumors with high (99m)Tc-TF retention (>/= 15%) exhibited a favorable response to chemoradiotherapy whereas all 12 tumors with low (99m)Tc-TF retention (</= 15%) did not respond to the therapy. In contrast, (201)Tl retention was not found to be a predictive factor.

CONCLUSIONS

The employed SPECT method is a useful tool for the in vivo prediction of radioresistance, P-glycoprotein (P-gp), and non-P-gp MDR in lung carcinoma. Low (99m)Tc-TF retention serves as a strong predictor of therapeutic resistance. High (99m)Tc-TF retention implies a favorable response. (201)Tl did not appear to be a predictive factor but is required for localization of the lesion on SPECT imaging.