Multimodal treatment for t1-2 supraglottic cancer: the impact of tumor location.

AIM: To examine the outcome and prognostic factors after multimodal treatment of T1-2 supraglottic cancer. PATIENTS AND METHODS: We analyzed 49 patients with T1-2 supraglottic cancer who received multimodal treatment between 1990 and 2011. Their age range was 43-86 years (median=66 years). Fifteen patients had a T1 tumor and 34 had a T2 tumor (40 N0, 3 N1, 4 N2, and 2 N3). Debulking using transoral laser excision was employed in 25 patients. Neck dissection was performed in four patients. Chemotherapy was administered to 29 patients: intra-arterial infusion in four and systemic infusion in 25. Radiotherapy was administered at a median dose of 64.8 Gy (range=30-70 Gy) with once- or twice-daily fractionation. Median follow-up time was 60 months (range=12-153 months). RESULTS: Two patients interrupted radiotherapy because of a poor response at 30 Gy (T2N2) and 49.9 Gy (T2N0). They underwent total laryngectomy and were still alive without any evidence of cancer 48 and 28 months after treatment, respectively. The other 47 patients (96%) had a complete local response to treatment. Locoregional failure was observed in six tumor sites, and one patient had simultaneous locoregional recurrence. The 5-year local control, disease-free, overall survival, and laryngeal preservation rates were 82%, 74%, 82%, and 90%, respectively. The location of a primary tumor within the supraglottis (epilarynx or elsewhere) was identified as the only factor predictive of progression-free survival by univariate and multivariate analyses (p=0.04). Acute adverse reactions of grade 3 or more were: one grade 3 laryngeal edema, one grade 3 dyspnea, and one grade 5 hematological toxicity (disseminated intravascular coagulation). Among late adverse events, one grade 1, one grade 2 hoarseness, and grade 3 laryngeal necrosis were observed. CONCLUSION: Multimodal radiotherapy produced a good outcome. Localization of the tumor in the epilarynx was associated with a better progression-free survival rate than that in the other parts of the supraglottis.

Relationship between 2-deoxy-2-[(18)F]-fluoro-d-glucose uptake and clinicopathological factors in patients with diffuse large B-cell lymphoma.

The aim of this study was to investigate correlations between the standardized uptake value of the biopsy site (BSUVmax) and levels of glucose transporter (GLUT)-1, GLUT-3 and hexokinase-II (HK-II), between BSUVmax and the Ki-67 proliferation index (MIB-1), and between BSUVmax and clinicopathological factors. Sixty-eight patients with diffuse large B-cell lymphoma (DLBCL) were included in this study. BSUVmax was significantly correlated with GLUT-1, GLUT-3 and the International Prognostic Index (IPI) (GLUT-1: r = 0.584, IPI: r = 0.363, p < 0.001; GLUT-3: r = 0.369, p = 0.009; IPI: r = 0.363, p = 0.004), but not with MIB-1 and HK-II. A statistically significant correlation was observed between GLUT-3 expression and each of IPI and gene expression profiling (GEP) (IPI: p = 0.0186; GEP: p = 0.0179). 2-Deoxy-2-[(18)F]-fluoro-d-glucose (FDG) uptake was significantly correlated with the levels of GLUT-1 and GLUT-3 and with IPI. The results indicated that GLUT-3 expression is related to GEP and IPI, and that BSUVmax and GLUT-3 may have a relationship with the prognosis of DLBCL.

The difference in relationship between 18F-FDG uptake and clinicopathological factors on thyroid, esophageal, and lung cancers.

OBJECTIVES: The aim of this study was to reveal the differences in clinicopathological factors affecting maximum standardized uptake value (SUVmax) between esophageal squamous cell carcinoma (ESCC), non-small-cell lung cancer (NSCLC), and papillary thyroid cancer (PTC). METHODS: This study consisted of 119 patients with ESCC (n=43), PTC (n=40), or NSCLC (n=36). We investigated the correlations between SUVmax and clinicopathological factors by using Spearman's correlation coefficient and the Kruskal-Wallis test. Multiple regression analysis was used to investigate which clinicopathological factors significantly affected SUVmax in each cancer type. RESULTS: The SUVmax correlated with glucose transporter-1 (GLUT-1) expression in NSCLC (r=0.536, P=0.007) and ESCC (r=0.597, P<0.001) but not in PTC. The SUVmax correlated with Ki-67 expression in NSCLC (r=0.381, P=0.022) and PTC (r=0.374, P=0.017) but not in ESCC. A high SUVmax was correlated with a higher pathological T stage (p-T stage) in NSCLC (r=0.536) and ESCC (r=0.597, both P<0.001) but not in PTC. An elevated SUVmax was significantly associated with pathological lymph node status (p-N) in NSCLC, but not in ESCC and PTC. In multiple regression analysis, p-T stage and GLUT-1 expression were statistically significant factors in ESCC, and p-T stage was a statistically significant factor in NSCLC. In PTC, Ki-67 showed a statistically significant association with SUVmax. CONCLUSION: SUVmax in NSCLC depended on the tumor invasion area; SUVmax in ESCC depended on tumor depth and GLUT-1 expression; and SUVmax in PTC might be associated with cell proliferation. The biological factors affecting SUVmax differ according to tumor type.

Non-surgical multimodality treatment for locally advanced (T3-4) hypopharyngeal cancer: the impact of pre-treatment hemoglobin level.

AIM: To examine the role of a non-surgical multimodality approach in patients with locally advanced pharyngeal cancer who refuse surgery or are inoperable. PATIENTS AND METHODS: Between 2006 and 2011, 19 patients with T3-4 hypopharyngeal cancer received multimodality non-surgical treatment. Out of these patients, nine refused surgery, and nine were inoperable. Their age range was 52-86 years (median, 68 years). Ten patients had T3, and 9 had T4 (two with stage III and 17 with stage IV). Neoadjuvant induction chemotherapy was administered in 11 patients. Hyperthermia was performed in patients with advanced lymph node metastasis. Radiotherapy was administered at a median of 61 Gy (60-61.2 Gy) in conventional fractionation. Concurrent chemotherapy was administered to all patients: through intra-arterial infusion in seven, systemic infusion in 10, or both in two. Median follow-up time was 27 months (range: 6-50 months). RESULTS: At the primary site, 16 patients (84%) achieved a complete response and three (16%) with partial response, resulting in a 100% response rate. Locoregional failure appeared in the form of six local and two regional lesions, and in one case in both types of lesions. Three-year local control, disease-free and overall survival rates, and laryngeal preservation rates were 65%, 48%, 50%, and 83%, respectively. Anemia was the only strong predisposing factor, not only for reduced local control but also for reduced progression-free and overall survival rates. Acute toxicities of grade 3 or more included hematological toxicity in four patients, gastrointestinal toxicity in two, and pneumonia in 6. Late adverse reaction of dysphagia grade 3 was found in one patient, whereas dysphagia grade 4 was not observed. CONCLUSION: Multimodality non-surgical treatment could be a useful option for patients who refuse surgery and have inoperable disease with substantial curative potential without severe adverse reactions.

Pioglitazone decreases coronary artery inflammation in impaired glucose tolerance and diabetes mellitus: evaluation by FDG-PET/CT imaging.

OBJECTIVES: The aim of this study was to compare the effect of pioglitazone with glimepiride on coronary arterial inflammation with serial (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) combined with computed tomography (CT) angiography. BACKGROUND: Recent studies have shown that FDG-PET combined with CT is a reliable tool to visualize and quantify vascular inflammation. Although pioglitazone significantly prevented the progression of coronary atherosclerosis and reduced the recurrence of myocardial infarction in patients with type 2 diabetes mellitus (DM), it remains unclear whether pioglitazone could attenuate coronary artery inflammation. METHODS: Fifty atherosclerotic patients with impaired glucose tolerance or type 2 DM underwent determination of blood chemistries, anthropometric and inflammatory variables, and FDG-PET/CT angiography, and then were randomized to receive either pioglitazone or glimepiride for 16 weeks. Effects of the treatments on vascular inflammation of the left main trunk were evaluated by FDG-PET/CT angiography at baseline and end of the study. Vascular inflammation of the left main trunk was measured by blood-normalized standardized uptake value, known as a target-to-background ratio. RESULTS: Three patients dropped out of the study during the assessment or treatment. Finally, 25 pioglitazone-treated patients and 22 glimepiride-treated patients (37 men; mean age: 68.1 ± 8.3 years; glycosylated hemoglobin: 6.72 ± 0.70%) completed the study. After 16-week treatments, fasting plasma glucose and glycosylated hemoglobin values were comparably reduced in both groups. Changes in target-to-background ratio values from baseline were significantly greater in the pioglitazone group than in the glimepiride group (-0.12 ± 0.06 vs. 0.09 ± 0.07, p = 0.032), as well as changes in high-sensitivity C-reactive protein (pioglitazone vs. glimepiride group: median: -0.24 [interquartile range (IQR): -1.58 to -0.04] mg/l vs. 0.08 [IQR: -0.07 to 0.79] mg/l, p = 0.031). CONCLUSIONS: Our study indicated that pioglitazone attenuated left main trunk inflammation in patients with impaired glucose tolerance or DM in a glucose-lowering independent manner, suggesting that pioglitazone may protect against cardiac events in patients with impaired glucose tolerance or DM by suppressing coronary inflammation. (Anti-Inflammatory Effects of Pioglitazone; NCT00722631).

Quantitative evaluation of light scattering intensities of the crystalline lens for radiation related minimal change in interventional radiologists: a cross-sectional pilot study.

To evaluate low-dose X-ray radiation effects on the eye by measuring the amount of light scattering in specific regions of the lens, we compared exposed subjects (interventional radiologists) with unexposed subjects (employees of medical service companies), as a pilot study. According to numerous exclusionary rules, subjects with confounding variables contributing to cataract formation were excluded. Left eye examinations were performed on 68 exposed subjects and 171 unexposed subjects. The eye examinations consisted of an initial screening examination, followed by Scheimpflug imaging of the lens using an anterior eye segment analysis system. The subjects were assessed for the quantity of light scattering intensities found in each of the six layers of the lens. Multiple stepwise regression analyses were performed with the stepwise regression for six variables: age, radiation exposure, smoking, drinking, wearing glasses and workplace. In addition, an age-matched comparison between exposed and unexposed subjects was performed. Minimal increased light scattering intensity in the posterior subcapsular region showed statistical significance. Our results indicate that occupational radiation exposure in interventional radiologists may affect the posterior subcapsular region of the lens. Since by its very nature this retrospective study had many limitations, further well-designed studies concerning minimal radiation-related lens changes should be carried out in a low-dose exposure group.

18F-FDG uptake in primary gastric malignant lymphoma correlates with glucose transporter 1 expression and histologic malignant potential.

Positron emission tomography (PET) is used for staging and response evaluation in primary gastric lymphoma (PGL). However, the implications of [(18)F]-2-fluoro-2-deoxy-D-glucose ((18)F-FDG) uptake in PGL at first diagnosis have not been reported. The relationship between (18)F-FDG uptake and the expression of facilitative glucose transporters (GLUTs), hexokinase II (HK II), and Ki67, as well as malignant potential in PGL, was assessed in this study. We analyzed 23 patients with PGL [nine with diffuse large B-cell lymphoma (DLBCL); seven with high-grade mucosa-associated lymphoid tissue (MALT) lymphoma; and seven with low-grade MALT lymphoma]. The expression levels of GLUT1, GLUT3, HK II, and Ki67 were evaluated according to the percentage of positive area determined by immunohistochemistry. Standardized uptake values correlated significantly with pathological malignant potentials (low-grade/high-grade MALT lymphoma and DLBCL: p = 0.001-0.002), Ki67 (p < 0.001), and GLUT1 expression (p = 0.02). We determined that (18)F-FDG uptake is related to GLUT1 expression and tumor histological grade as well as Ki67 in PGL.

A newly developed double lumen microballoon catheter with a side hole: initial experience of intraarterial infusion chemotherapy and/or embolization.

PURPOSE: To introduce a newly developed double lumen microballoon catheter with a side hole for intraarterial infusion chemotherapy and/or embolization. METHODS AND MATERIALS: Seven patients with malignant tumors, for whom superselective catheterization was considered difficult or had failed, underwent intraarterial infusion chemotherapy and/or embolization with the 3.3-Fr microballoon catheter. The catheter has a double lumen and a side hole to facilitate infusion from the proximal end of the balloon. The balloon was placed on the distal side of the target artery branching site. Inflation of the balloon and occlusion of the main lumen with the tip of the occlusion device allowed for intraarterial infusion chemotherapy and/or embolization of the target artery via the side hole. RESULTS: Successful intraarterial infusion chemotherapy and/or embolization with the microballoon catheter was performed in all patients with no complications. CONCLUSIONS: The newly developed microballoon catheter achieves intraarterial infusion chemotherapy and/or embolization without the need for superselective catheterization.

Positive association between serum level of glyceraldehyde-derived advanced glycation end products and vascular inflammation evaluated by [(18)F]fluorodeoxyglucose positron emission tomography.

OBJECTIVE: Advanced glycation end products (AGEs) evoke inflammatory reactions, contributing to the development and progression of atherosclerosis. We investigated the relationship between serum AGE level and vascular inflammation. RESEARCH DESIGN AND METHODS: The study involved 275 outpatients at Kurume University, Japan (189 males and 86 females; mean age 61.2 ± 8.8 years) who underwent complete history and physical examinations and determinations of blood chemistry and anthropometric variables, including AGEs. Serum AGE level was examined by enzyme-linked immunosorbent assay. Vascular [(18)F]fluorodeoxyglucose (FDG) uptake, an index of vascular inflammation, was measured as blood-normalized standardized uptake value, known as the target-to-background ratio (TBR), by FDG-positron emission tomography (FDG-PET). Furthermore, we examined whether the changes in serum AGE level after treatment with oral hypoglycemia agents (OHAs) were correlated with those of TBR in another 18 subjects whose AGE value was >14.2 units/mL (mean ± 2 SD). RESULTS: Mean serum AGE level and carotid TBR values were 9.15 ± 2.53 and 1.43 ± 0.22 units/mL, respectively. Multiple stepwise regression analysis revealed that TBR was independently correlated with AGEs (P < 0.001), carotid intima-media thickness (P < 0.01), and BMI (P < 0.02). When age- and sex-adjusted AGE values stratified by TBR tertiles were compared using ANCOVA, a significant trend was observed (P < 0.01). In addition, the changes in AGEs after OHA treatment were positively (r = 0.50, P < 0.05) correlated with those in TBR value. CONCLUSIONS: The current study reveals that serum AGE level is independently associated with vascular inflammation evaluated by FDG-PET, suggesting that circulating AGE value may be a biomarker that could reflect vascular inflammation within an area of atherosclerosis.

Automated estimation of number of implanted iodine-125 seeds for prostate brachytherapy based on two-view analysis of pelvic radiographs.

Digital pelvic radiographs are used to identify the locations of implanted iodine-125 seeds and their numbers after insertion. However, it is difficult and laborious to visually identify and count all implanted seeds on the pelvic radiographs within a short time. Therefore, our purpose in this research was to develop an automated method for estimation of the number of implanted seeds based on two-view analysis of pelvic radiographs. First, the images of the seed candidates on the pelvic image were enhanced using a difference of Gaussian filter, and were identified by binarizing the enhanced image with a threshold value determined by multiple-gray level thresholding. Second, a simple rule-base method using ten image features was applied for false positive removal. Third, the candidates for the likely number of a multiply overlapping seed region, which may include one or more seeds, were estimated by a seed area histogram analysis and calculation of the probability of the likely number of overlapping seeds. As a result, the proposed method detected 99.9% of implanted seeds with 0.71 false positives per image on average in a test for training cases, and 99.2% with 0.32 false positives in a validation test. Moreover, the number of implanted seeds was estimated correctly at an overall recognition rate of 100% in the validation test using the proposed method. Therefore, the verification time for the number of implanted seeds could be reduced by the provision of several candidates for the likely number of seeds.

Pelvic arteriovenous malformation treated by superselective transcatheter venous and arterial embolization.

We describe a rare case of hematuria and hemospermia associated with pelvic arteriovenous malformation (AVM) in a male patient treated by transcatheter embolization. Understanding AVM hemodynamics contributes to the elucidation of its pathology and improves the outcome of embolization. In the present case, multiple arteriolar components shunted to the initial part of a single dominant outflow vein. Superselective embolization of a draining vein and feeding artery with an n-butyl cyanoacrylate/lipiodol mixture and polyvinyl alcohol particles was effective in terms of shunt disappearance and minimizing the need for subsequent arterial embolization.

The relationship between GLUT-1 and vascular endothelial growth factor expression and 18F-FDG uptake in esophageal squamous cell cancer patients.

PURPOSE: To examine the relationship between glucose transporter-1 (GLUT-1) and vascular endothelial growth factor (VEGF) expression and (18)F-FDG uptake in esophageal squamous cell cancer patients. MATERIALS AND METHODS: Fifty-seven patients (52 male and 5 female) were included in this study. (18)F-FDG PET/CT was performed prior to the surgery. Immunohistochemistry was performed using postoperative histopathological specimens. The estimation of immunohistochemistry was conducted using scoring analysis. We investigated the correlations between maximum standardized uptake value (SUV(max)) and GLUT-1/VEGF expressions/pathologic tumor length (p-tumor length), and the relationships between pathologic T (p-T) stage and GLUT-1/VEGF expressions/SUV(max) and between lymph node metastasis (p-N) stage and GLUT-1/VEGF expressions/SUV(max). RESULTS: SUV(max) significantly correlated with GLUT-1 expressions and p-tumor length (GLUT-1: r = 0.475, P < 0.001; p-tumor length: r = 0.475, P < 0.001). SUV(max) of the primary tumor had a significant relationship with p-T stage, p-N stage, and VEGF expression (p-T stage: P < 0.001; p-N stage: P = 0.037; VEGF expression: P = 0.009). There was a statistically significant difference between GLUT-1 expression and p-T stage/VEGF expression, but not p-N stage (p-T stage: P = 0.012; VEGF expression: P = 0.01; p-N stage: P = 0.572). VEGF expression had a significant relationship with p-T stage, but not with p-N stage (p-T stage: P = 0.032; p-N stage: P = 0.763). CONCLUSION: (18)F-FDG uptake can be determined by GLUT-1 and VEGF. SUV(max) would have a connection with the tumor progression and lymph node metastasis.

Quantification of hepatic iron concentration in chronic viral hepatitis: usefulness of T2-weighted single-shot spin-echo echo-planar MR imaging.

OBJECTIVE: To investigate the usefulness of single-shot spin-echo echo-planar imaging (SSEPI) sequence for quantifying mild degree of hepatic iron stores in patients with viral hepatitis. METHODS: This retrospective study included 34 patients with chronic viral hepatitis/cirrhosis who had undergone histological investigation and magnetic resonance imaging with T2-weighted gradient-recalled echo sequence (T2-GRE) and diffusion-weighted SSEPI sequence with b-factors of 0 s/mm(2) (T2-EPI), 500 s/mm(2) (DW-EPI-500), and 1000 s/mm(2) (DW-EPI-1000). The correlation between the liver-to-muscle signal intensity ratio, which was generated by regions of interest placed in the liver and paraspinous muscles of each sequence image, and the hepatic iron concentration (µmol/g dry liver), which was assessed by spectrophotometry, was analyzed by linear regression using a spline model. Akaike information criterion (AIC) was used to select the optimal model. RESULTS: Mean ± standard deviation of the hepatic iron concentration quantified by spectrophotometry was 24.6 ± 16.4 (range, 5.5 to 83.2) µmol/g dry liver. DW-EPI correlated more closely with hepatic iron concentration than T2-GRE (R square values: 0.75 for T2-EPI, 0.69 for DW-EPI-500, 0.62 for DW-EPI-1000, and 0.61 for T2-GRE, respectively, all P<0.0001). Using the AIC, the regression model for T2-EPI generated by spline model was optimal because of lowest cross validation error. CONCLUSION: T2-EPI was sensitive to hepatic iron, and might be a more useful sequence for quantifying mild degree of hepatic iron stores in patients with chronic viral hepatitis.

Ultraselective arterial embolization of vasa recta using 1.7-French microcatheter with small-sized detachable coils in acute colonic hemorrhage after failed endoscopic treatment.

OBJECTIVE: The purpose of this article is to document our experiences with ultraselective arterial embolization to manage acute colonic hemorrhage using a 1.7-French microcatheter with small-sized detachable coils and to discuss the feasibility and clinical efficacy of this new technique. CONCLUSION: We achieved technical success in all four patients with the sole use of short-segment embolization of the long branch of the vasa recta. Our findings suggest that this technique is useful for embolization in cases of colonic hemorrhage.

Evaluation of overall tumor cellularity after neoadjuvant chemotherapy in patient with locally advanced hypopharyngeal cancer.

The aim of this study is to clarify the prognostic value of the pathological overall tumor cellularity after neoadjuvant chemotherapy for locally advanced hypopharyngeal cancer. In consecutive series of 45 operable patients with locally advanced hypopharyngeal cancer, neoadjuvant chemotherapy by cisplatin and 5-fluorouracil was administered. Pathological image analysis was performed in 30 patients using the large cross-section specimen after total resection to evaluate the overall tumor cellularity. The chemotherapeutic responses were classified according to the pathological grading scale by dividing into four categories; more than 70% overall tumor cellularity in Grade 1, between an estimated 10 and 70% in Grade 2, less than 10% in Grade 3, and no identifiable malignant tumor cells in Grade 4. The pathological grades were taken into account for analysis of the survival. In 30 available patients, 40% had Grade 1 pathological response, 30% had Grade 2, and 30% had Grade 3. There was no Grade 4 patient. The overall 5-year survival rate for these 30 patients was 53.33%. The survival rate (61.66%) for patients with Grade 2 and 3 responses was significantly higher than that (27.78%) for patients with Grade 1 response (p = 0.009). Cox regression analysis revealed that the increasing pathological grade was an independent predictor of a better survival in patients undergoing neoadjuvant chemotherapy. We have shown that the prognosis of patients with locally advanced hypopharyngeal cancer, who had been treated by neoadjuvant chemotherapy followed by total resection, can be predicted by evaluation of pathological overall tumor cellularity from the large section specimen.

Assessment of Chronic Pancreatitis: Use of Whole Pancreas Perfusion With 256-Slice Computed Tomography.

OBJECTIVE: We aimed to compare perfusion computed tomography (CTP) characteristics of the normal pancreas with those of chronic pancreatitis (CP) and to examine the possibility of evaluating pancreatic exocrine function with CTP. METHODS: Thirty-two patients (control group, n = 18; CP group, n = 14) who completed the whole pancreas CT perfusion examination with 256-slice CT were studied. Four parameters, including perfusion (PF), peak enhancement intensity (PEI), time-to-peak (TTP), and blood volume (BV), were measured and compared between the control and CP groups, and between patients with and without exocrine pancreatic insufficiency (EPI) in the CP group. Pancreatic exocrine function was determined via serum trypsinogen. RESULTS: There was no significant difference between the distribution of PF, PEI, and BV in different pancreas regions, namely, the head, body, and tail (P > 0.05). PF, PEI, and BV of the CP group were significantly decreased, and TTP was significantly increased compared with the control group (P < 0.05). A significant decrease of PF, PEI, and BV and increase of TTP were observed in patients with EPI than in patients without EPI (P < 0.05). CONCLUSIONS: Perfusion CT is an appropriate imaging technique to diagnose CP and may be useful as a screening test to rule out early EPI.

Comparison between endoscopic macroscopic classification and F-18 FDG PET findings in gastric mucosa-associated lymphoid tissue lymphoma patients.

PURPOSE: The aim of this study was to compare endoscopic macroscopic classification with fluorine-18 fluorodeoxyglucose (F-18 FDG) uptake in gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to investigate the usefulness of F-18 FDG positron emission tomography (PET) for diagnosing gastric MALT lymphoma. MATERIALS AND METHODS: Sixteen patients with gastric MALT lymphoma who underwent F-18 FDG PET and gastrointestinal imaging modalities were included in this study. Sixteen healthy asymptomatic participants undergoing both F-18 FDG PET and endoscopy for cancer screening were in the control group. We investigated the difference of F-18 FDG uptake between the gastric MALT lymphoma and the control group and compared the uptake pattern in gastric MALT lymphoma with our macroscopic classification. RESULTS: The endoscopic findings of 16 gastric MALT lymphoma patients were classified macroscopically as chronic gastritis-like tumors (n = 6), depressed tumors (n = 5), and protruding tumors (n = 5). Abnormal gastric F-18 FDG uptake was observed in 63% of tumors in the gastric MALT lymphoma group and 50% of cases in the control group. The median maximum standardized uptake values for gastric MALT lymphoma patients and control group were 4.0 and 2.6, respectively, the difference of which was statistically significant (P = 0.003). F-18 FDG uptake results were positive for all protruding tumors but only 50% for chronic gastritis-like tumors and 40% for depressed-type tumors. CONCLUSIONS: F-18 FDG PET may be a useful method for evaluating protrusion-type gastric MALT lymphoma. When strong focal or diffuse F-18 FDG uptake is detected in the stomach, endoscopic biopsy should be performed, even if the endoscopic finding is chronic gastritis.