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Nitric oxide (NO) shows tumoricidal activity. We had previously reported that NO downregulates the phosphatidylinositol-3-kinase/Akt pathway, but upregulates the MEK/ERK pathway downstream of growth factor signaling. We hypothesized that NO donor and MEK inhibitor in combination synergistically inhibit the viability of cancer cells compared to either NO donor or MEK inhibitor alone. We determined the effects of S-nitrosoglutathione (GSNO, NO-donor) and U0126 (MEK inhibitor) on insulin-like growth factor-I (IGF-I) and epidermal growth factor (EGF) signaling, proliferation and invasion in cancer cell lines. GSNO inhibits phosphorylation of IGF-I receptor (IGF-IR), EGF receptor (EGFR) and Akt, but upregulates ERK1/2 phosphorylation in MIAPaCa-2 and HCT-116 cells after stimulation by IGF-I and EGF. On the other hand, U0126 inhibits phosphorylation of ERK1/2, but upregulates phosphorylation of IGF-IR and EGFR in MIAPaCa-2 and HCT-116 cells. The combination of GSNO and U0126 downregulates phosphorylation of IGF-IR, EGFR, Akt and ERK1/2 after stimulation by IGF-I and EGF. GSNO as well as U0126, inhibits the proliferation of MIAPaCa-2, HCT-116, Panc-1, MCF-7, HT-29 and AGS cells in a dose-dependent manner. GSNO and U0126 in combination synergistically inhibit proliferation and invasion of cancer cells. These results indicate that the combined treatment of NO donor and MEK inhibitor may be promising in cancer therapy.

Solid-pseudopapillary tumors of the pancreas (SPTs) are comparatively rare and have low malignancy, with a predilection for young women. Diagnosis is difficult when a SPT develops in a boundary region with other organs. Here, we report a 42-year old woman with a SPT of the pancreas mimicking a submucosal tumor of the stomach on imaging. She was admitted to our hospital complaining of abdominal pain. We suspected a submucosal tumor of the stomach from the findings of endoscopy, endoscopic ultrasonography and abdominal computed tomography. However, angiography showed that some of the tumor vessels arose from the pancreas. Intraoperative findings revealed the tumor originated from the pancreas. Therefore, distal pancreatectomy was performed. The pathological diagnosis was SPT of the pancreas.

A 77-year-old male was admitted to our hospital complaining of dyschezia. Computed tomography (CT) and colonoscopy (CF) revealed a huge sigmoid colon cancer invading the bladder and seminal vesicle. Chemotherapy with mFOLFOX6 was initiated preoperatively, and the tumor shrunk markedly after seven courses of treatment. Pelvic exenteration with negative margins was carried out. The patient is still alive and disease-free 16 months after surgery. It was suggested that mFOLFOX6 may be useful for advanced colon cancer invading other organs when used as neoadjuvant chemotherapy.

Background: This study was designed to define the diagnostic advantage of computed tomography during arterial portography (CTAP) combined with computed tomography-assisted hepatic arteriography (CTHA) for the preoperative detection of liver metastases secondary to pancreatic cancer compared with that of multidetector computed tomography (MDCT)., Methods: From January 2002 to December 2007, we retrospectively studied 197 consecutive patients with pancreatic cancer. MDCT was performed on 192 patients prior to preoperative visceral angiography; 153 patients underwent CTAP + CTHA at the time of preoperative angiography., Results: Liver metastases were identified in 39 patients by means of MDCT. Of the 153 patients who had no evidence of liver metastases on MDCT, 129 patients underwent CTAP + CTHA, and 53 of these 129 patients (41.1%) were diagnosed as having liver metastases that could not be detected by MDCT. These tumors missed by MDCT ranged from 3 to 15 mm in size. On CTAP + CTHA, a solitary nodule in the liver was detected in 11 patients, 2 nodules were detected in 6 patients, 3 lesions were detected in 2 patients, and ≧4 lesions were detected in 34 patients. The sensitivity and specificity of CTAP + CTHA versus MDCT were 94.2 versus 48.4% and 82.7 versus 97.9%, respectively., Conclusions: The combination of CTAP and CTHA is useful to confirm liver metastases and can potentially offer more accurate staging of pancreatic cancer compared with MDCT.

Primary pleural synovial sarcoma is a rare disease with poor outcomes. Although hyperthermia therapy as part of a combined treatment regimen can offer improved local tumor control, only two reports of hyperthermia therapy for synovial sarcoma have appeared in the literature, and these sarcomas were not of pleuropulmonary origin. This report of an advanced inoperable primary pleural synovial sarcoma is the first to address the use of hyperthermia therapy in combination with chemoradiotherapy for this disease, together with radiological assessment following that therapy. Computed tomography performed after thermoradiation showed a decrease in tumor size and a characteristic unenhanced low-density area in the tumor suggesting that tumor necrosis resulted from the therapy. These image findings were helpful in assessing the tumor response to thermoradiation. We believe that hyperthermia therapy combined with chemoradiotherapy should be regarded as an option for advanced primary pleural synovial sarcoma. This would give computed tomography important role in evaluating this approach.

A 75-year-old woman was admitted to our department because of epigastric pain. Imagings revealed cancer of the head of the pancreas. She was an HBV carrier, although no liver dysfunction was observed. Her serum HBV-DNA level was lower than 2.6. We performed pancreaticoduodenectomy for pancreatic cancer. No postoperative complication was observed. The histopathological diagnosis was tubular adenocarcinoma of the pancreas. As a postoperative adjuvant chemotherapy, gemcitabine hydrochloride (GEM) was injected at a dose of 800mg/m2 once a week. Disorientation and jaundice were observed after six doses of GEM. Blood chemistry revealed that total bilirubin and ammonia were abnormally elevated, and that blood coagulant factors were diminished. Serum HBV-DNA level was lower than 2.6. It showed no reactivation of HBV. Abdominal CT showed no recurrence but fatty liver. Fresh frozen plasma was supplied and branched chain amino acids were injected after GEM was administration discontinued. Lactulose was also given orally. With these conservative treatments, she recovered completely. Careful monitoring of liver function during GEM administration is required in a HBV carrier.

Thermal modulation voltammetry (TMV) using laser heating at a liquid/liquid microinterface is a useful technique for determining the standard entropy change of ion transfer. In this work, for achieving TMV using a visible laser as a heating source at a 1,2-dichloroethane (DCE)/water microinterface, we used an optically absorbing supporting electrolyte, i.e., crystalviolet tetrakis(4-chlorophenyl)borate (CVTClPB). CVTClPB served well not only as a supporting electrolyte but also as an optical absorber in the DCE solution, and thereby, well-defined linear sweep (LS) and TM voltammograms could be obtained. On the basis of LS and thermal modulation (TM) voltammograms obtained with CVTClPB, the standard entropy changes of ion transfer for six model ions were successfully determined.

The patient was a 63-year-old woman with a chief complaint of blood-stained sputum. A tumor of the inferior vena cava was found on chest computed tomography (CT) and identified as a primary tumor based on multidetector CT and contrast-enhanced MR angiography. An intrapelvic tumor was also discovered. On autopsy, the two tumors were diagnosed as leiomyosarcoma and ovarian fibroma, respectively.

Nitric oxide (NO), which plays a role in the posttranslational modification of proteins, exhibits tumoricidal activity. However, the mechanism remains largely unclear. We investigated whether the regulation of insulin receptor substrate (IRS)-1 protein expression and insulin/insulin-like growth factor (IGF) signaling by NO is involved in the proliferation and invasion of pancreatic cancer cells. NO donor inhibited insulin/IGF-I-stimulated phosphorylation of insulin receptor/IGF-I receptor, IRS-1, Akt/PKB, and glycogen synthase kinase-3beta along with decreased expression of IRS-1 protein in MIAPaCa-2 cells, whereas NO donor enhanced the phosphorylation of extracellular signal-regulated kinase-1/2. In contrast, a selective inducible nitric oxide synthase inhibitor, 1400W, upregulated the expression of IRS-1 protein and the phosphorylation of IRS-1, Akt/PKB, and glycogen synthase kinase-3beta, along with enhanced proliferation and invasion of Panc-1 cells expressing inducible nitric oxide synthase protein. NO donor induced IRS-1 protein reduction through increased ubiquitination and degradation. For the detection of the site responsible for NO-induced ubiquitination, IRS-1 deletion mutant genes were transfected and overexpressed in MIAPaCa-2 cells. The results indicate that the COOH terminus of the IRS-1 protein is required for NO donor-induced ubiquitination and protein degradation. Cells stably transfected with COOH-terminal deletion mutants of IRS-1 exhibited reduced IGF signaling and cell proliferation compared with vector alone-transfected cells, with no influence of NO on IGF signaling and invasion, although stable transfectants with full-length IRS-1 protein exhibited remarkable NO-induced reduction in IGF signaling, cell proliferation, and invasion. These findings indicate that NO inhibits the proliferation and invasion of pancreatic cancer cells, at least in part, through upregulation of IRS-1 protein degradation and resultant downregulation of the insulin/IGF-I-Akt pathway.

Background: Mortality rates after pancreaticoduodenectomy (PD) are below 4% in high volume centers, although morbidity rates still remain high. Therefore, it is important to clarify a predictor associated with operative morbidity after PD. The estimation of physiologic ability and surgical stress (E-PASS) score has been developed for comparative audit in general surgical patients., Objective: To evaluate whether E-PASS scoring system could predict the occurrence of complications after PD., Methods: We performed retrospective analysis of 69 patients (42.0% pancreatic cancer, 31.9% bile duct cancer, and others) who underwent PD using the E-PASS as a predictor of morbidity. Correlations between the incidence rates of postoperative complications and the preoperative risk score (PRS), surgical stress score (SSS) and comprehensive risk score (CRS) of the E-PASS scoring system were evaluated., Results: Of the 69 patients 30 (43.5%) experienced a total of 54 postoperative complications. All E-PASS scores, especially PRS and CRS were significantly higher in the patients with postoperative complications than in the patients without complication. The complication rate gradually increased as the PRS, SSS and CRS score increased. Under receiver operating characteristic analysis, if a cut-off point of CRS was 0.75, sensitivity and specificity for the prediction of operative morbidity after PD was 80.0 and 79.5%, respectively. Neoadjuvant chemotherapy and intraoperative radiation therapy (IORT) did not influenced on operative morbidity after PD., Conclusion: E-PASS scoring system is useful to evaluate for morbidity after PD. Neoadjuvant chemotherapy and IORT could be adapted without significant extra risk for surgical complication.

Background: Little is known about the clinical significance of TS and DPD in pancreatic cancer. We aimed to evaluate TS and DPD expression levels in not only pancreatic cancer but also surrounding normal pancreatic tissues to assess the clinical implications of the expression of TS and DPD in this study., Patients and Methods: Pancreatic cancer and normal pancreatic tissues were obtained from 18 patients with pancreatic cancer who underwent pancreatic resection to measure TS and DPD activities. The TS and DPD activities were determined by enzyme-linked immunosorbent assay using non-fixed fresh-frozen specimens., Results: Pancreatic cancer tissues had significantly higher DPD and TS enzyme activities than surrounding normal tissue. Anaplastic ductal carcinoma had higher DPD and TS activities than the other histological types. Patients with high DPD in this study demonstrated poorer prognosis than those with low DPD. On the other hand, there was no statistically significant difference in survival between the high and the low TS groups., Conclusions: The efficacy of 5-FU may be lower in pancreatic cancer tissue than in normal tissue because DPD activity is upregulated in pancreatic cancer tissue compared to normal pancreatic tissue. It is necessary to develop an effective 5-FU delivery system and/or 5-FU combined with an inhibitor for DPD that can be used when 5-FU must be administered to patients with pancreatic cancer. High DPD activity may be a prognostic factor in patients with pancreatic cancer.

The characteristics of jejunal ectopic pancreas in dynamic gadolinium-enhanced magnetic resonance imaging are described in a 40-year-old man with bowel obstruction. The pre-contrast signal intensity and post-contrast enhancement pattern of ectopic pancreas are the same as those of the pancreas.

Although accurate information on thoracolumbar bone structure is essential when computed tomography (CT) images are examined, there is no automated method of labeling all the vertebrae and ribs on a CT scan. We are developing a computer-aided diagnosis system that labels ribs and thoracolumbar vertebrae automatically and have evaluated its accuracy. A candidate bone was extracted from the CT image volume data by pixel thresholding and connectivity analysis. All non-bony anatomical structures were removed using a linear discriminate of distribution of CT values and anatomical characteristics. The vertebrae were separated from the ribs on the basis of their distances from the centers of the vertebral bodies. Finally, the thoracic cage and lumbar vertebrae were extracted, and each vertebra was labeled with its own anatomical number by histogram analysis along the craniocaudal midline. The ribs were labeled in a similar manner, based on location data. Twenty-three cases were used for accuracy comparison between our method and the radiologist's. The automated labeling of the thoracolumbar vertebrae was concordant with the judgments of the radiologist in all cases, and all but the first and second ribs were labeled correctly. These two ribs were frequently misidentified, presumably because of pericostal anatomical clutter or high densities of contrast material in the injected veins. We are confident that this system can contribute usefully as part of a picture archiving and communication system workstation, though further technical improvement is required for identification of the upper ribs.

Background: As a modification of hand-assisted laparoscopic pancreatectomy, we devised a method of spleen and gastrosplenic ligament preserving distal pancreatectomy, in which pancreatic resection is performed under direct vision extracorporeally., Methods: The distal pancreas and spleen are pulled out of the peritoneal cavity through the minilaparotomy at the epigastrium following hand-assisted laparoscopic dissection of the distal pancreas. Spleen-preserving pancreatectomy is performed safely under direct vision. The gastrosplenic ligament is also preserved to prevent splenic volvulus after the operation. The transected main pancreatic duct is doubly ligated, and the transected pancreatic stump is sewn manually. The preserved spleen and splenic vessels are placed back in the peritoneal cavity after resection., Results: In the current study (n = 3), overall morbidity rate, including splenic volvulus and pancreatic fistula, was 0%., Conclusion: Preservation of the gastrosplenic ligament and extracorporeal preparation of the transected pancreatic stump under direct vision are useful measures in spleen-preserving distal pancreatectomy under a minimum incision approach assisted by laparoscopy.

A 65-year-old man was diagnosed as esophageal cancer with multiple liver metastases (S2 10 mm, S7 10 mm, S8 15 mm). The preoperative diagnosis was stage IV (T 3 N 3 M 1 Pl 0), and he was operated palliatively by esophagocardiofundectomy and intrathoracic anastomosis for oral food intake. The postoperative histological diagnosis was adenosquamous carcinoma. One month after the operation he was administered orally UFT-E (300 mg/day) and PSK (3g/day). He was also treated by hepatic arterial infusion therapy with CDDP (10 mg/week). After 180 mg of CDDP, liver metastases were evaluated for PR. This therapy was discontinued after 410 mg of CDDP by vomiting and hypotension. 16 months after, DOC (20 mg/week) was given by arterial infusion and CR of liver metastases was achieved 18 months after. Then he was given 840 mg of DOC and oral administration of UFT-E and PSK was performed for about 5 years. He was free from the recurrence of cancer as an outpatient and had a good QOL. We think that esophageal cancer with liver metastasis should be aggressively treated surgically so as to allow oral food intake, and liver metastasis should be treated with chemotherapy because postoperative hepatic arterial infusion therapy is effective and provides a good QOL.

There is no established or effective standard therapy for metastatic biliary tract cancer, resulting in poor prognosis. Recently, we performed combination chemotherapy of irinotecan and low-dose cisplatin (I/low-P) for three consecutive patients with metastatic biliary tract cancer. The regimen of I/low-P therapy consisted of irinotecan (60 mg/m(2)) and low-dose cisplatin (6 mg/m(2)), administered by intravenous infusion weekly or biweekly. Of the three patients, two showed a partial response, with durations of more than 20 months, and 2 months, respectively, while the third patient had stable disease for 3 months. One patient, who had jaundice, had grade 3 thrombocytopenia, but the other patients did not have any severe toxicities. Survival times were more than 20 months, 10 months, and 13 months, respectively. These outcomes suggest that I/low-P therapy is safe and may be worth trying as a first-line chemotherapy for patients with metastatic biliary tract cancer.

Anomalous origin of the right coronary artery (RCA) is a rare condition, but may cause myocardial ischemia and sudden death. Multislice computed tomography, which allows three-dimensional visualization of the coronary artery with high spatial resolution, may be the most promising imaging modality for diagnosing this anomaly. We describe a patient with anomalous origin of the RCA arising from the left sinus of Valsalva. Volume rendering, and axial and curved multiplanar images showed stenosis in the proximal portion of the RCA that coursed between the aorta and the pulmonary artery, and an acute angled take-off of the RCA from the aorta. Three-dimensional virtual angioscopic images showed a hypoplastic RCA orifice and luminal narrowing in the proximal portion of the RCA. Multislice computed tomography was thought to be useful for detecting anomalous origin of the RCA and for evaluating possible causes of myocardial ischemia.

We have examined the utility of the convex echo probe, which has the fine gutter of a puncture needle in laparoscopic radio frequency ablation therapy. When we use a flexible linear echo probe in RFA treatment, we have to puncture tumor with the hand piece in free hand. But it is difficult to treat in the case of HCC which is located in S1 and the lower area of S5 and S6 because we have a narrow space where colon, duodenum and netz are close for safe and exact puncturing of the tumor. We used a convex echo probe in RFA to the above mentioned area of the liver. We punctured with the hand piece exactly and easily without preliminary puncturing of the tumor. So we can perform RFA treatment successfully and safely by a choice of an appropriate echo probe.

Background: The diagnosis of acute coronary syndrome (ACS), especially non-ST-elevation myocardial infarction and unstable angina in the emergency department (ED) still remains a challenge. Multislice computed tomography (MSCT) allows assessment of not only coronary artery stenoses and occlusions, but also assessment of coronary artery plaques and myocardial perfusion status., Methods and Results: MSCT was performed in 31 patients who were admitted to the ED because of chest pain persisting at least 30 min and non-diagnostic ECG changes and normal serum enzyme concentrations. Using MSCT, ACS was defined by coronary artery stenosis > or = 75% accompanied by computed tomography (CT)-low-density plaques, and/or by the presence of myocardial perfusion defects. ACS was confirmed by coronary stenosis > or = 75% by coronary angiography and/or subsequent elevation of troponin I concentration. In total, 22 patients were diagnosed as having ACS. MSCT detected stenoses with CT-low-density plaques in 21 and non-transmural myocardial perfusion defect in 3 patients. There was 1 false-positive and 1 false-negative result. The sensitivity and specificity of MSCT to identify ACS was 95.5% and 88.9%, respectively., Conclusion: MSCT provides diagnostic operating characteristics suitable for triage of patients with ACS in the ED.

Background: Anomalous origins of the coronary artery are rare, but may cause myocardial ischemia and sudden death. Thus, their reliable identification is crucial for any imaging method that attempts coronary artery visualization and of those available multislice computed tomography (MSCT), which provides excellent spatial resolution, may be the most promising., Methods and Results: In consecutive 1,153 patients, MSCT identified 5 patients (0.43 %) with an anomalous origin of the coronary artery. The left circumflex artery (LCX) originated from the right sinus of Valsalva in 1 patient, and the right coronary artery originated from the left sinus of Valsalva and coursed between the aortic root and the pulmonary artery in 3 patients. In 1 patient, MSCT identified the absence of the LCX and high-grade atherosclerotic stenosis in the right coronary artery., Conclusion: MSCT can detect the anomalous origin and course of the coronary artery in relation to the great vessels. It is also useful for identifying atherosclerotic coronary artery disease superimposed on the anomalous vascular system.

The high spatial resolution of multislice computed tomography (MSCT) permits direct visualization of the coronary artery system. In this report, we describe coronary artery abnormalities in a young adult with Kawasaki disease. MSCT detected a giant coronary artery aneurysm, coronary artery stenosis in the first diagonal artery, and a multi-layered structure in the right coronary artery and the left circumflex artery. These findings corresponded well to those obtained by coronary angiography. MSCT has the potential to be the standard diagnostic tool for the follow-up evaluation of coronary artery disease in adolescents and young adults with Kawasaki disease.

Multislice spiral computed tomography (MSCT) permits direct visualization of not only coronary artery stenosis but also atherosclerotic plaques in patients with coronary artery disease. In this report, we describe a patient with stable angina in whom the regression of the plaque was documented by serial MSCT examinations. In the patient, a 46-year-old man with stable angina, MSCT revealed a stenotic lesion at the proximal portion of the left anterior descending artery. Axial, curved multiplanar reconstruction and cross-sectional images consistently depicted a protruding computed tomography low-signal mass suggesting an atherosclerotic plaque. Intracoronary ultrasound (ICUS) also documented an eccentric soft plaque with an echo-lucent mass suggesting a lipid core. Lipid-lowering therapy with pravastatin was started. Follow-up MSCT performed 7 months later documented an increase in the luminal area while the external vessel area remained unchanged. The regression of the plaque was also confirmed by a follow-up ICUS study. MSCT was thought to be feasible for serial evaluation of the plaque size and texture.

The present study was designed to investigate the accuracy of multislice spiral computed tomography (MSCT) in detecting coronary artery disease, compared with coronary angiography (CAG), using a new retrospectively ECG-gated reconstruction method that reduced cardiac motion artifact. The study group comprised 54 consecutive patients undergoing MSCT and CAG. MSCT was performed using a SOMATOM Volume Zoom (4-detector-row, Siemens, Germany) with slice thickness 1.0 mm, pitch 1.5 (table feed: 1.5 mm per rotation) and gantry rotation time 500 ms. Metoprolol (20-60 mg) was administered orally prior to MSCT imaging. ECG-gated image reconstruction was performed with the reconstruction window (250 ms) positioned immediately before atrial contraction in order to reduce the cardiac motion artifact caused by the abrupt diastolic ventricular movement occurring during the rapid filling and atrial contraction periods. Following inspection of the volume rendering images, multiplanar reconstruction images and axial images of the left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex artery (LCx) and right coronary artery (RCA) were obtained and evaluated for luminal narrowing. The results were compared with those obtained by CAG. Of 216 coronary arteries, 206 (95.4%) were assessable; 10 arteries were excluded from the analysis because of severe calcification (n=4), stents (n=3) or insufficient contrast enhancement (n=3). The sensitivity to detect coronary stenoses >or=50% was 93.5% and the specificity to define luminal narrowing <50% was 97.2%. The positive predictive value and the negative predictive value were 93.5% and 97.2%, respectively. The sensitivity was still satisfactory (80.6%) even when non-assessable arteries were included in the analysis. The new retrospectively ECG-gated reconstruction method for MSCT has excellent diagnostic accuracy in detecting significant coronary artery stenoses.

Although the excellent spatial resolution of multislice spiral computed tomography (MSCT) enables the coronary arteries to be visualized, its limited temporal resolution results in poor image reproducibility because of cardiac motion artifact (CMA) and hence limits its widespread clinical use. A novel retrospectively ECG-gated reconstruction method has been developed to minimize CMA. In 88 consecutive patients, the scan data were reconstructed using 2 retrospectively ECG-gated reconstruction methods. Method 1: the end of the reconstruction window (250 ms) was positioned at the peak of the P wave on ECG, which corresponded to the end of the slow filling phase during diastole immediately before atrial contraction. Method 2 (conventional method): relative retrospective gating with 50% referred to the R-R interval was performed so that the beginning of the reconstruction window (250 ms) was positioned at the halfway point between the R-R intervals of the heart cycle. The quality of the coronary artery images was evaluated according to the presence or absence of CMA. The assessment was applied to the left main coronary artery (LMCA), the left anterior descending artery (LAD, segments #6, #7 and #8), the left circumflex artery (LCx, segments #11 and #13) and the right coronary artery (RCA, segments #1, #2 and #3). The first diagonal artery (#9-1), the obtuse marginal artery (#12-1), the posterior descending artery (#4-PD), the atrioventricular node branch (#4-AV) and the first right ventricular branch (RV) were also evaluated. Of the 88 patients, 85 were eligible for image evaluation. Method 1 allowed visualization of the major coronary arteries without CMA in the majority of patients. The LCA system (segments #5-7, #11 and #13) and the proximal portion of the RCA were visualized in more than 94% of patients. Artifact-free visualization of the distal portion of the LAD (segment #8) and RCA (#4PD and #4AV), and side branches (#9-1, #12-1 and RV) was also achieved in more than 80% of patients. On the other hand, CMA occurred frequently on images obtained by Method 2. The LCx and RCA systems were the most affected by CMA, revealing only 41% artifact-free visualization of the segment #13, 39% of #1, 15% of #2 and 32% of #3. Thus, Method 1, which avoids the ventricular motion occurring during the rapid filling and atrial contraction phases, gives superior image quality over the conventional ECG-gated reconstruction method.

Purpose: We report a patient who suffered from prolonged loss of taste acuity after partial oral cavity irradiation., Methods: The electric taste threshold (ETT) of each point in the oral cavity was measured with an electric gustometer to evaluate quantitative local taste acuity. A subjective total taste acuity (STTA) scale was used to evaluate subjective total taste acuity., Case: A 61-year-old male patient with right buccal mucosal cancer underwent radiation therapy more than 11 years ago, and has suffered from loss of taste acuity since then. He received electron beam irradiation to part of the oral cavity and right upper neck, mainly the right buccal mucosa near the retromolar trigone and a metastatic right submandibular node. He did not receive irradiation to the anterior portion of the tongue or left side of the posterior portion of the tongue. His ETT scores for each point were equal to or greater than 26, and his STTA score was grade 3., Conclusion: The present case implies that radiation damage to part of the oral cavity can cause the loss of subjective total taste acuity.