Stability of standardized uptake values for quantitative bone SPECT for jawbone lesions: a single-center cross-sectional study.

BACKGROUND: The long time required for bone uptake of radiopharmaceutical material after injection for bone scintigraphy is a burden for patients with poor health. Thus, to assess whether the uptake time could be reduced for single-photon emission computed tomography (SPECT) of the jawbone, this study evaluated differences in maximum standardized uptake values (SUVmax) within patients using SPECT imaging at 2 and 3 hours after radiopharmaceutical injection. METHODS: A total of 33 patients undergoing treatment or in post-treatment follow-up for medication-related osteonecrosis of the jaw, who visited our hospital between July 2020 and August 2021 and could receive SPECT twice on the same day, were enrolled in the study. Patients were injected with technetium-99 m hydroxymethylene diphosphonate (Tc-99 m HMDP) intravenously. The SUVmax for healthy parietal bones and jawbone lesions were calculated from the SPECT images using quantitative analysis software, and the SUVmax were compared between 2- and 3-hour uptake times. RESULTS: After exclusion, 30 patients were included in the study. In the 2-hour and 3-hour images, the median SUVmax of the parietal bones were 1.90 and 1.81, respectively, and those of the jawbone lesions were 9.25 and 9.39, respectively. The limits of agreement (LOA) ranged from - 0.33 to 0.25 in the parietal bones, and the %LOA ranged from - 9.8 to 17.3% in the jawbone lesions, showing high equivalence between the two uptake durations. The SUVmax showed no clinical differences between the 2- and 3-hour uptake durations for Tc-99 m HMDP SPECT of the jawbone. CONCLUSIONS: The results of this study justify a 2-3-hour uptake window when performing quantitative SPECT of the jawbone. Therefore, the minimum uptake time can potentially be reduced to only 2 hours.

Prevalence of and risk factors for postoperative complications after lower third molar extraction: A multicenter prospective observational study in Japan.

Lower third molar extraction is the most common surgical treatment among routine dental and oral surgical procedures. while the surgical procedures for lower third molar extraction are well established, the difficulty of tooth extraction and the frequency of postoperative complications differ depending on the patient's background. To establish a management protocol for the lower third molars, the prevalence of and risk factors for postoperative complications after lower third molar extraction were investigated in a large number of Japanese patients in a multicenter prospective study. During 6 consecutive months in 2020, 1826 lower third molar extractions were performed at the 20 participating institutions. The medical records of the patients were reviewed, and relevant data were extracted. The prevalence of and risk factors for postoperative complications were analyzed. The prevalence of postoperative complications after lower third molar extraction was 10.0%. Multivariate analysis indicated that age (≤32 vs >32, odds ratio [OR]: 1.428, 95% confidence interval [95% CI]: 1.040-1.962, P < .05), the radiographic anatomical relationship between the tooth roots and mandibular canal (overlapping of the roots and canal vs no close anatomical relationship between the roots and the superior border of the canal, OR: 2.078, 95% CI: 1.333-3.238, P < .01; overlapping of the roots and canal vs roots impinging on the superior border of the canal, OR: 1.599, 95% CI: 1.050-2.435, P < .05), and impaction depth according to the Pell and Gregory classification (position C vs position A, OR: 3.7622, 95% CI: 2.079-6.310, P < .001; position C vs position B, OR: 2.574, 95% CI: 1.574-4.210, P < .001) are significant independent risk factors for postoperative complications after lower third molar extraction. These results suggested that higher age and a deeply impacted tooth might be significant independent risk factors for postoperative complications after lower third molar extraction.

Oral adverse events due to zinc deficiency after pancreaticoduodenectomy requiring continuous intravenous zinc supplementation: a case report and literature review.

BACKGROUND: Zinc is mainly absorbed in the duodenum and proximal jejunum, which are removed during pancreaticoduodenectomy (PD). Little is known about the adverse oral events and skin disorders caused by zinc deficiency after PD. Herein, we reviewed studies on the development of zinc deficiency after PD and reported about a patient with zinc deficiency after PD who required home intravenous zinc replacement. CASE PRESENTATION: A 73-year-old woman with glossitis, taste disorder, and acrodermatitis enteropathica-like eruption on her fingers presented to the Division of Dentistry and Oral Surgery 69 days after PD. Her serum zinc level markedly decreased to 30 µg/dL. Oral zinc administration was inadequate to treat hypozincemia after PD; therefore, multi-trace elements were injected intravenously during readmission. Her serum zinc levels recovered, and her lesions gradually improved. Furthermore, a central venous port was implanted to maintain normal serum zinc levels, and she continued self-injecting zinc at home. CONCLUSIONS: Zinc deficiency after PD rarely occurs. The clinical oncologist community, including dentists responsible for the oral care of cancer patients, should be aware of the oral adverse events, such as dysgeusia, glossitis, and oral pain, associated with zinc deficiency after cancer surgery and that induced by chemotherapy or head and neck radiation therapy.

Prognosis by cancer type and incidence of zoledronic acid-related osteonecrosis of the jaw: a single-center retrospective study.

PURPOSE: Survival time after bisphosphonate use has been increasingly recognized to be associated with the incidence of medication-related osteonecrosis of the jaw (MRONJ); however, this has not been elucidated sufficiently in the literature. This study aimed to clarify the incidence of MRONJ and the corresponding survival rate of patients treated with zoledronic acid (ZA) for each type of cancer and obtain useful information for the oral/dental supportive care of cancer patients. METHODS: We evaluated 988 patients who were administered ZA at our hospital; among them, 862 patients with metastatic bone tumors or myeloma were included. RESULTS: The median survival time (MST) after ZA initiation was 35, 34, 8, 41, 12, and 6 months for patients with breast, prostrate, lung, myeloma, renal, and other cancers, respectively. Patients with cancers that had a short survival time (lung and other cancers [MST = 8 and 6 months, respectively] and cancers with MST < 10 months) did not develop MRONJ; this could be attributed to the shorter duration of ZA administration. The cumulative incidence of MRONJ in breast cancer, prostate cancer, and multiple myeloma was related to the frequency of anti-resorptive drug use and the increased risk over time. In renal cancer, the cumulative incidence of MRONJ increased early, although the MST was 12 months. CONCLUSION: For the dentists in charge of dental management, it is essential to be aware of prognosis-related factors, predict MRONJ risk for each cancer treatment, and use risk prediction in dental management planning, particularly for cancers with non-poor prognosis.

Oral care and oral assessment guide in breast cancer patients receiving everolimus and exemestane: subanalysis of a randomized controlled trial (Oral Care-BC).

BACKGROUND: Oral mucositis is a clinically significant adverse event linked to cancer therapy; it reduces the quality of life of patients and may result in the discontinuation of treatment and a poorer prognosis. Based on level 3 evidence, the Mucositis Study Group of Multinational Association for Supportive Care in Cancer and the International Society of Oral Oncology recommend oral care for all patients receiving cancer chemotherapy and radiotherapy, although no data from large-scaled randomized controlled trials support the efficacy of oral care in preventing oral mucositis. Therefore, this randomized, controlled, multicenter, open-label, phase III study sought to determine whether professional oral care reduces oral mucositis in everolimus and exemestane-treated estrogen receptor-positive metastatic breast cancer patients. METHODS: Altogether, 169 patients were randomized into the professional oral care (n=82) and control (n=87) groups. The professional oral care group received oral health instruction, professional mechanical tooth and tongue cleaning, gargling with a benzethonium chloride mouthwash, and dexamethasone ointment when grade 1 mucositis manifested. The control group received oral health instruction and gargling. Eight weeks after the everolimus and exemestane administration, the oral status (Oral Assessment Guide criteria) and oral mucositis status (Common Terminology Criteria for Adverse Events functional and clinical examinations) were evaluated. RESULTS: The incidence of oral mucositis of any grade and grade 2 severe mucositis was significantly lower in the professional oral care group, based on the Common Terminology Criteria for Adverse Events functional and clinical examinations. The total Oral Assessment Guide score, total Oral Assessment Guide grade, and Oral Assessment Guide score of teeth/dentures and mucous membranes were significantly different between the two groups. The Oral Assessment Guide grade for swallow, lip, teeth/dentures, mucous membrane, tongue, and saliva significantly correlated to oral mucositis severity. CONCLUSIONS: Professional oral care may prevent oral mucositis and improve teeth/denture conditions in patients receiving everolimus and exemestane.

Analgesic effects of indomethacin spray on drug-induced oral mucositis pain in patients with cancer: A single-arm cross-sectional study.

AIMS: Symptomatic treatment is insufficient for chemotherapy- or targeted therapy-induced oral mucositis (OM) pain, and benzydamine mouthwash is not commercially available in Japan. We evaluated the analgesic effects of an in-hospital preparation of 0.25% indomethacin spray (IMS) on anticancer drug-induced OM pain. METHODS: This single-arm prospective trial enrolled 20 patients (median age 62.0 years) with OM and numerical rating scale scores of ≥5 who were undergoing chemotherapy or targeted therapy in our hospital. Pain scores were recorded using a visual analog scale (VAS) before and 30 min after IMS administration. Pain relief (PR) scores were recorded at 15, 30, and 60 min after IMS administration; total PR after 60 min (TOTPAR60 ) was calculated, and the mean PR score after 3 days (PR3days ) was determined. RESULTS: The median (interquartile range) OM grade of the participants was 2.0 (2.0-2.3). The VAS score decreased significantly at 30 min after IMS administration (p = .001). The median (interquartile range) TOTPAR60 and PR3days were 6.0 (3.8-7.3) and 2.0 (2.0-3.0), respectively. CONCLUSIONS: IMS helped improve patients' quality of life. The risk of systemic adverse effects was low because of the low dose administered. IMS effectively relieved anticancer drug-induced OM pain and may be useful for immediate self-medication.

Secondary endpoints analysis in patients with estrogen receptor-positive metastatic breast cancer treated with everolimus and exemestane enrolled in Oral Care-BC.

BACKGROUND: The Oral Care BC-trial reported that professional oral care (POC) reduces the incidence and severity of oral mucositis in patients receiving everolimus (EVE) and exemestane (EXE). However, the effect of POC on clinical response among patients receiving EVE and EXE was not established. We compared outcomes for estrogen receptor-positive metastatic breast cancer patients who received POC to those who had not, and evaluated clinical prognostic factors. All patients simultaneously received EVE and EXE. METHODS: Between May 2015 and Dec 2017, 174 eligible patients were enrolled in the Oral Care-BC trial. The primary endpoint was the comparative incidence of grade 1 or worse oral mucositis, as evaluated for both the groups over 8 weeks by an oncologist. The secondary endpoints were progression-free survival (PFS) and overall survival (OS). Data were collected after a follow-up period of 13.9 months. RESULTS: There were no significant differences in PFS between the POC and Control Groups (P = 0.801). A BMI <  25 mg/m2 and non-visceral metastasis were associated with longer PFS (P = 0.018 and P = 0.003, respectively) and the use of bone modifying agents (BMA) was associated with shorter PFS (P = 0.028). The PFS and OS between the POC and control groups were not significantly different in the Oral-Care BC trial. CONCLUSIONS: POC did not influence the prognosis of estrogen receptor-positive metastatic breast cancer patients. Patients with non-visceral metastasis, a BMI <  25 mg/m2, and who did not receive BMA while receiving EVE and EXE may have better prognoses. TRIAL REGISTRATION: The study protocol was registered online at the University Hospital Medical Information Network (UMIN), Japan (protocol ID 000016109), on January 5, 2015 and at ClinicalTrials.gov ( NCT02376985 ).

Quantitative bone single photon emission computed tomography analysis of the effects of duration of bisphosphonate administration on the parietal bone.

Effects of long-term bisphosphonate (BP) administration on the metabolism of healthy bone and the concomitant changes in imaging are unclear. Hence, we aimed to retrospectively investigate the effects of long-term BP administration on the intact parietal bone using the standardised uptake value (SUV) derived from single photon emission computed tomography (SPECT). We enrolled 29 patients who had odontogenic infection, osteoporosis, bone metastasis cancer, or rheumatoid arthritis, and classified them into BP-naïve: A (14 patients) and BP-treated: B, < 4 years (7 patients) and C, ≥ 4 years (8 patients) groups. We measured the maximum bilateral SUV (SUVmax) of the parietal bone using quantitative bone SPECT software. There were significant differences in the duration of BP administration and SUVmax of the parietal bone among the diseases (P < 0.0001 and P = 0.0086, respectively). There was a positive correlation between the duration of BP administration and SUVmax of the parietal bone (rs = 0.65, P = 0.0002). The SUVmax was significantly different between A and B (P = 0.02) and between A and C (P = 0.0024) groups. This is the first report on the correlation between long-term BP administration and the SUVmax of the parietal bone using the quantitative bone SPECT analysis.

Monitoring indices of bone inflammatory activity of the jaw using SPECT bone scintigraphy: a study of ARONJ patients.

Development of quantitative analysis software has enabled application of several standardised uptake values (SUV) for bone analysis in single photon emission computed tomography (SPECT). The present retrospective study aimed to develop a reliable method of monitoring bone inflammatory activity in antiresorptive agent-related osteonecrosis of the jaw (ARONJ) using SPECT quantitative analysis software. Fifteen ARONJ patients underwent SPECT before and after anti-inflammatory therapy. We calculated the mean maximum SUV (SUVmax) of the bilateral cranial bones using quantitative analysis software and used this as the control [C]. We attempted to adjust the SUVmax of the lesion [L] as follows: adjusted SUVmax (aSUVmax) = [L] - [C]. The optimum threshold to calculate the metabolic bone volume (MBV) (cm3) was [C] + 3. The threshold values obtained for each case were input to calculate MBV at each osteomyelitis site. Retrospectively, we compared aSUVmax and MBV of each patient's ARONJ before and after anti-inflammatory therapy. The patients' high aSUVmax or large MBV of the ARONJ reduced rapidly, reflecting individual clinical findings after treatment. Application of SPECT quantitative analysis software to monitor bone inflammatory activity in ARONJ could improve the prognosis-deciding abilities of clinicians and enable them to treat ARONJ effectively.

Oral Care Evaluation to Prevent Oral Mucositis in Estrogen Receptor-Positive Metastatic Breast Cancer Patients Treated with Everolimus (Oral Care-BC): A Randomized Controlled Phase III Trial.

BACKGROUND: The incidence of oral mucositis (any grade) after everolimus treatment is 58% in the general population and 81% in Asian patients. This study hypothesized that professional oral care (POC) before everolimus treatment could reduce the incidence of everolimus-induced oral mucositis. MATERIALS AND METHODS: This randomized, multicenter, open-label, phase III study evaluated the efficacy of POC in preventing everolimus-induced mucositis. Patients were randomized into POC and control groups (1:1 ratio) and received everolimus with exemestane. Patients in the POC group underwent teeth surface cleaning, scaling, and tongue cleaning before everolimus initiation and continued to receive weekly POC throughout the 8-week treatment period. Patients in the control group brushed their own teeth and gargled with 0.9% sodium chloride solution or water. The primary endpoint was the incidence of all grades of oral mucositis. We targeted acquisition of 200 patients with a 2-sided type I error rate of 5% and 80% power to detect 25% risk reduction. RESULTS: Between March 2015 and December 2017, we enrolled 175 women from 31 institutions, of which five did not receive the protocol treatment and were excluded. Over the 8 weeks, the incidence of grade 1 oral mucositis was significantly different between the POC group (76.5%, 62 of 82 patients) and control group (89.7%, 78 of 87 patients; p = .034). The incidence of grade 2 (severe) oral mucositis was also significantly different between the POC group (34.6%, 28 of 82 patients) and control group (54%, 47 of 87 patients; p = .015). As a result of oral mucositis, 18 (22.0%) patients in the POC group and 28 (32.2%) in the control group had to undergo everolimus dose reduction. CONCLUSION: POC reduced the incidence and severity of oral mucositis in patients receiving everolimus and exemestane. This might be considered as a treatment option of oral care for patients undergoing this treatment. Clinical trial identification number: NCT02069093. IMPLICATIONS FOR PRACTICE: The Oral Care-BC trial that prophylactically used professional oral care (POC), available worldwide, did not show a greater than 25% difference in mucositis. The 12% difference in grade 1 or higher mucositis and especially the ∼20% difference in grade 2 mucositis are likely clinically meaningful to patients. POC before treatment should be considered as a treatment option of oral care for postmenopausal patients who are receiving everolimus and exemestane for treatment of hormone receptor-positive, HER2-negative advanced breast cancer and metastatic breast cancer. However, POC was not adequate for prophylactic oral mucositis in these patients, and dexamethasone mouthwash prophylaxis is standard treatment before everolimus.

Relationship between acetaldehyde concentration in mouth air and characteristics of microbiota of tongue dorsum in Japanese healthy adults: a cross-sectional study.

OBJECTIVE: Acetaldehyde, associated with consumption of alcoholic beverages, is known to be a carcinogen and to be related to the tongue dorsum. The aim of this study was to investigate the relationship between acetaldehyde concentration in mouth air and bacterial characteristics on the tongue dorsum. METHODOLOGY: Thirty-nine healthy volunteers participated in the study. Acetaldehyde concentrations in mouth air were evaluated by a high-sensitivity semiconductor gas sensor. A 16S rRNA gene sequencing technique was used to compare microbiomes between two groups, focusing on the six samples with the highest acetaldehyde concentrations (HG) and the six samples with lowest acetaldehyde concentrations (LG). RESULTS: Acetaldehyde concentration increased in correlation with the increase in bacterial count (p=0.048). The number of species observed in the oral microbiome of the HG was higher than that in the oral microbiome of the LG (p=0.011). The relative abundances of Gemella sanguinis, Veillonella parvula and Neisseria flavescens in the oral microbiome of the HG were higher than those in the oral microbiome of the LG (p<0.05). CONCLUSION: Acetaldehyde concentration in mouth air was associated with bacterial count, diversity of microbiome, and relative abundance of G. sanguinis, V. parvula, and N. flavescens.

Change in tongue pressure and the related factors after esophagectomy: a short-term, longitudinal study.

BACKGROUND: Dysphagia is a prominent symptom after esophagectomy and may cause aspiration pneumonia. Swallowing evaluation after esophagectomy can predict and help control the incidence of postoperative pneumonia. The aim of this study was to clarify whether the change in tongue pressure was associated with any related factor and postoperative dysphagia/pneumonia in patients with esophageal cancer after esophagectomy. METHODS: Fifty-nine inpatients (41 males and 18 females; 33-77 years old) who underwent esophagectomy participated in this study. Measurement of tongue pressure and the repetitive saliva swallowing test (RSST) was performed before esophagectomy (baseline) and at 2 weeks postoperatively. The general data were collected from patients' medical records, including sex, age, type of cancer, cancer stage, location of cancer, operative approach, history of previous chemotherapy, surgical duration, amount of bleeding during surgery, incidences of postoperative complications, intubation period, period between surgery and initiation of oral alimentation, and intensive care unit (ICU) stay, blood chemical analysis, and lifestyle. RESULTS: Tongue pressure decreased significantly after esophagectomy (p = 0.011). The decrease of tongue pressure was significantly associated with length of ICU stay and preoperative tongue pressure on multiple regression analysis (p < 0.05). The decrease of tongue pressure in the RSST < 3 or postoperative pneumonia (+) group was significantly greater than in the RSST ≥ 3 (p = 0.003) or pneumonia (-) group (p = 0.021). CONCLUSIONS: The decrease in tongue pressure was significantly associated with the length of ICU stay, preoperative tongue pressure, and the incidence of dysphagia and pneumonia among inpatient after esophagectomy.

Imaging modalities for drug-related osteonecrosis of the jaw (3), Positron emission tomography imaging for the diagnosis of medication-related osteonecrosis of the jaw.

Medication-related osteonecrosis of jaws (MRONJ) is one of the most complicated inflammatory conditions in oral and maxillofacial region. It is very difficult to correctly evaluate the degree and extent of necrosis and infection. This refractory osteonecrosis often needs extended surgery, leading to impaired quality-of-life. We have performed hyperbaric oxygen therapy (HBO) combined with conservative surgery for advanced cases. We have appraised the value of FDG-PET and 3-phase bone scintigraphy in the diagnosis and management of this condition. MRONJ showed significantly higher SUVmax on FDG-PET than the others. Although the 3 phase pool bone images did not change significantly, perfusion and static bone image as well as PET showed remarkable response to HBO for MRONJ. SUVmax after HBO was significantly lower than those of before HBO. These preliminary results indicate that FDG-PET is useful for monitoring the effect of HBO for MRONJ.

Relationship between acetaldehyde concentration in mouth air and characteristics of microbiota of tongue dorsum in Japanese healthy adults: a cross-sectional study

Abstract Acetaldehyde, associated with consumption of alcoholic beverages, is known to be a carcinogen and to be related to the tongue dorsum. Objective The aim of this study was to investigate the relationship between acetaldehyde concentration in mouth air and bacterial characteristics on the tongue dorsum. Methodology Thirty-nine healthy volunteers participated in the study. Acetaldehyde concentrations in mouth air were evaluated by a high-sensitivity semiconductor gas sensor. A 16S rRNA gene sequencing technique was used to compare microbiomes between two groups, focusing on the six samples with the highest acetaldehyde concentrations (HG) and the six samples with lowest acetaldehyde concentrations (LG). Results Acetaldehyde concentration increased in correlation with the increase in bacterial count (p=0.048). The number of species observed in the oral microbiome of the HG was higher than that in the oral microbiome of the LG (p=0.011). The relative abundances of Gemella sanguinis, Veillonella parvula and Neisseria flavescens in the oral microbiome of the HG were higher than those in the oral microbiome of the LG (p<0.05). Conclusion Acetaldehyde concentration in mouth air was associated with bacterial count, diversity of microbiome, and relative abundance of G. sanguinis, V. parvula, and N. flavescens.

Elimination of oral candidiasis may increase stimulated whole salivary flow rate.

OBJECTIVES: Candida infections are frequently encountered fungal infections in the oral mucosa. This study aimed to evaluate the effect of eliminating Candida spp. on stimulated whole salivary flow rate (SWS) in patients with oral candidiasis. SUBJECTS AND METHODS: This study involved 66 patients with oral candidiasis. Fifty-two consecutive patients, successfully treated by antifungal therapy, were available to examine the effect of elimination of oral Candida spp. on SWS (success group); the 14 patients who tested positive for Candida after therapy were retrospectively included (control group). SWS were used to measure saliva production. Moreover, tongue pain and xerostomia were evaluated using visual analog score (VAS). RESULTS: By eliminating oral Candida spp., SWS significantly increased in the success group after antifungal therapy [SWS: mean value 0.89±0.51ml/min (median 0.82ml/min: 0.15-2.14) to mean value 1.16±0.58ml/min (median 1.05ml/min: 0.2-2.93), P<0.001]. Furthermore, VAS scores for subjective tongue pain and xerostomia were significantly decreased compared with those before therapy in the success group [xerostomia: mean value 52.5±28.8 (median 53: 9-100) to 24.2±1.6 (median 17: 0-70), tongue pain: mean value 52.6±27.2 (median 56: 1-93) to 15.3±18.0 (median 9: 0-62). P<0.001]. There was no significant difference in SWS, subjective tongue pain, or xerostomia in the control group after antifungal therapy. [SWS: mean value 1.08±0.83ml/min (median 0.69ml/min: 0.2-2.7) to 0.98±0.59ml/min (median 0.8ml/min: 0.45-2.5), P=0.65], [xerostomia: mean value 62.8±5.3 (median 62: 28-70) to 64.0±8.8 (median 64: 56-73), P=0.58, tongue pain: mean value 64.3±18.6 (median 67: 31-87) to 58.4±20.0 (median 8: 20-78), respectively; P=0.24] CONCLUSION: Our study demonstrated that SWS may increase by eliminating oral Candida spp. in patients with oral candidiasis.

Differences in sequential posttreatment salivary IL-6 levels between patients with and patients without locoregional recurrences of oral squamous cell carcinoma: Part III of a cohort study.

OBJECTIVE: Sequential postoperative salivary interleukin-6 (IL-6) concentrations were examined in patients with oral squamous cell carcinoma (OSCC) who had early or late locoregional recurrences or those who did not. STUDY DESIGN: Twenty-seven consecutive patients with OSCC were originally included in the study. All patients underwent radical surgery. Four saliva samples were collected before (periods I and II) and after (periods III and IV) surgery, and IL-6 concentrations were measured. RESULTS: Although postoperative (period III: at the time of discharge) salivary IL-6 level was significantly higher in patients with early locoregional recurrence (P = .02) than in those without, no such relationships were observed for preoperative IL-6 concentrations (periods I and II). Postoperative (period IV: 24 months after surgery) IL-6 level was significantly higher in patients with late locoregional recurrence (P = .03) than in those without, but no such relationships were observed for IL-6 concentrations in periods I, II, and III. CONCLUSIONS: Sequential postoperative salivary IL-6 concentration may be a useful marker for diagnosis of early and late locoregional recurrence in OSCC.

FDG-PET may predict the effectiveness of hyperbaric oxygen therapy in a patient with bisphosphonate-related osteonecrosis of the jaw: report of a case.

We report an advanced case of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in an osteoporotic patient treated with oral risedronate sodium for 2 years. An 80-year-old woman presented to our hospital complaining of pain, swelling and pus discharge in the lower alveolar ridge. Fluorine-18 labeled fluorodeoxyglucose positron emission tomography (FDG-PET) and bone scintigraphy showed definite uptake in the mandible. Under clinical diagnosis of BRONJ, we applied systematic treatments including antibiotic therapy, irrigation, cessation of bisphosphonate, hyperbaric oxygen (HBO) therapy, and debridement of necrotic bone. After pre-operative 20 sessions of HBO therapy, her clinical symptoms disappeared. SUVmax of FDG-PET decreased definitely from 4.5 to 2.5, although magnetic resonance image and bone scintigraphy did not show remarkable changes. After minor surgery with debridement of necrotic bone, she received another ten sessions of HBO therapy. After the treatment, her clinical course was excellent. In conclusion, this report demonstrates FDG-PET may predict the effect of HBO therapy in BRONJ.

Detailed assessment of gene activation levels by multiple hypoxia-responsive elements under various hypoxic conditions.

OBJECTIVE: HIF-1/HRE pathway is a promising target for the imaging and the treatment of intractable malignancy (HIF-1; hypoxia-inducible factor 1, HRE; hypoxia-responsive element). The purposes of our study are: (1) to assess the gene activation levels resulting from various numbers of HREs under various hypoxic conditions, (2) to evaluate the bidirectional activity of multiple HREs, and (3) to confirm whether multiple HREs can induce gene expression in vivo. METHODS: Human colon carcinoma HCT116 cells were transiently transfected by the constructs containing a firefly luciferase reporter gene and various numbers (2, 4, 6, 8, 10, and 12) of HREs (nHRE+, nHRE-). The relative luciferase activities were measured under various durations of hypoxia (6, 12, 18, and 24 h), O2 concentrations (1, 2, 4, 8, and 16 %), and various concentrations of deferoxamine mesylate (20, 40, 80, 160, and 320 µg/mL growth medium). The bidirectional gene activation levels by HREs were examined in the constructs (dual-luc-nHREs) containing firefly and Renilla luciferase reporter genes at each side of nHREs. Finally, to test whether the construct containing 12HRE and the NIS reporter gene (12HRE-NIS) can induce gene expression in vivo, SPECT imaging was performed in a mouse xenograft model. RESULTS: (1) gene activation levels by HREs tended to increase with increasing HRE copy number, but a saturation effect was observed in constructs with more than 6 or 8 copies of an HRE, (2) gene activation levels by HREs increased remarkably during 6-12 h of hypoxia, but not beyond 12 h, (3) gene activation levels by HREs decreased with increasing O2 concentrations, but could be detected even under mild hypoxia at 16 % O2, (4) the bidirectionally proportional activity of the HRE was confirmed regardless of the hypoxic severity, and (5) NIS expression driven by 12 tandem copies of an HRE in response to hypoxia could be visualized on in vivo SPECT imaging. CONCLUSION: The results of this study will help in the understanding and assessment of the activity of multiple HREs under hypoxia and become the basis for hypoxia-targeted imaging and therapy in the future.

Advantage of FMISO-PET over FDG-PET for predicting histological response to preoperative chemotherapy in patients with oral squamous cell carcinoma.

PURPOSE: Hypoxia, a prognostic factor in many types of cancer, can be detected by (18)F-fluoromisonidazole (FMISO) positron emission tomography (PET). It is unclear whether hypoxia reflects the response to chemotherapy in patients with oral squamous cell carcinoma (OSCC). The correlations of FMISO-PET and FDG-PET with histological response to preoperative chemotherapy were therefore assessed in patients with OSCC. METHODS: This study enrolled 22 patients with OSCC undergoing preoperative chemotherapy. The T-stages were T2 in 6 patients, T3 in 3, and T4a in 13, and the N-stages were N0 in 14 patients, N1 in 3, and N2 in 5. Each patient was evaluated by both FMISO-PET and FDG-PET before surgery, and the maximum standardized uptake value (SUVmax) of FDG- and FMISO-PET and tumor-muscle ratio (TMR) of FMISO-PET were measured. The threshold for the hypoxic volume based on TMR was set at 1.25. The histological response to preoperative chemotherapy was evaluated using operative materials. RESULTS: FMISO-PET and FDG-PET detected uptake by primary OSCCs in 15 (68%) and 21 (95%) patients, respectively, and median SUVmaxs of FMISO- and FDG-PET in the primary site were 2.0 (range, 1.3-3.5) and 16.0 (range, 1.0-32.2), respectively. The median of FMISO TMR was 1.5 (range, 0.99-2.96). There were five cases whose FMISO TMR was less than 1.25. Histological evaluation showed good response to preoperative chemotherapy in 7 patients (32%) and poor response in 15 (68%). Good response was significantly more prevalent in patients with negative than positive FMISO uptake (P < 0.001) and without the hypoxic area evaluated by FMISO-PET TMR (P = 0.04), whereas FDG uptake was not significantly correlated with response to chemotherapy response. Multivariate logistic regression analysis showed that FMISO uptake was an independent significant predictor of response to preoperative chemotherapy (P = 0.03, odds ratio = 0.06, 95% confidence interval = 0.004-0.759). CONCLUSIONS: An advantage of FMISO-PET over FDG-PET for predicting histological response to preoperative chemotherapy in patients with OSCC was observed.