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Sheng-Chieh Chan

Publications and source records attributed to Sheng-Chieh Chan.

14 recordsLinked to original sources
PubMed2006

Prospective study of [18F]fluorodeoxyglucose positron emission tomography and computed tomography and magnetic resonance imaging in oral cavity squamous cell carcinoma with palpably negative neck.

PURPOSE: To assess the clinical usefulness of [(18)F]fluorodeoxyglucose positron emission tomography ([18F]FDG PET) as well as computed tomography (CT) or magnetic resonance imaging (MRI) in oral squamous cell carcinoma (SCC) patients with palpably negative neck. PATIENTS AND METHODS: In total, 134 oral SCC patients with palpably negative neck were prospectively evaluated with [18F]FDG PET, CT/MRI, and their visual correlation. Histopathologic analysis was used as the gold standard for assessment of these imaging techniques. RESULTS: Thirty-five (26.1%) of our 134 patients were found to have neck metastases. On a level-by-level basis, the sensitivity of [18F]FDG PET for nodal metastases was two-fold higher than that of CT/MRI (41.2% v 21.6%, respectively; P = .021). Visual correlation of [(18)F]FDG PET and CT/MRI yielded slightly higher sensitivity and specificity than [18F]FDG PET alone (47.1% v 41.2%, P = .25; 98.0% v 96.8%, P = .125, respectively). On a patient-by-patient basis, the sensitivity of [18F]FDG PET for neck metastases was 51.4% and increased to 57.1% after visual correlation with CT/MRI. The probabilities of occult neck metastasis after using [(18)F]FDG PET were 6.7% in T1 tumors, 10.8% in T2 tumors, 13.3% in T3 tumors, and 25% in T4 tumors and decreased to 3.3% in T1 tumors and to 9.2% in T2 tumors after visual correlation with CT/MRI. CONCLUSION: [(18)F]FDG PET was superior to CT/MRI for detecting palpably occult neck metastasis of oral SCC. Because [(18)F]FDG PET could reduce the probability of occult neck metastasis to less than 15% in T1 to T3 tumors, it should be indicated for evaluation of these subpopulations.

Adult↗
PubMed2006

18F-FDG-PET for evaluation of the response to concurrent chemoradiation therapy with intensity-modulated radiation technique for Stage T4 nasopharyngeal carcinoma.

PURPOSE: This article evaluates [18F] fluorodeoxyglucose positron emission tomography (18F-FDG-PET) findings as a predictor for local responders (R) vs. nonresponders (NR) in nasopharyngeal carcinoma (NPC) patients with Stage T4 lesions, before and at 3 months after completion of concurrent chemotherapy and radiation therapy (CCRT). METHODS AND MATERIALS: From January 2002 to November 2003, 39 T4 NPC patients were enrolled. All had magnetic resonance imaging and 18F-FDG-PET, both before and 3 months after CCRT. Any residual/recurrent lesions were confirmed histopathologically. RESULTS: Of the 39 eligible patients, after a follow-up of 24.2 +/- 9.5 months, 35 became disease-free and 4 had residual or recurrent disease. Marginal differences in standard uptake values (SUV) were observed (10.9 +/- 5.3 vs. 15.6 +/- 3.4, p = 0.058) between R and NR before treatment, and value changes of SUV before and after CCRT were not significantly different. However, highly significantly lower values of SUV were noted for R than for NR 3 months after completion of CCRT (2.1 +/- 0.8 vs. 5.5 +/- 3.2, p = 0.001). One hundred percent positive and negative predictive values were observed for SUV values of 4.0, set 3 months after completion of CCRT. CONCLUSIONS: Neither the pretreatment SUV nor the changes of SUV between pretreatment and posttreatment were significant predictors for local response. SUV at 3 months after completion of CCRT was a significant determinator for local response. The cutoff of 4.0 for SUV at 3 months after completion of CCRT was useful to be offered as a diagnostic reference for recurrent or residual tumor for NPC treatment.

Adolescent↗
PubMed2006

Advantages and pitfalls of 18F-fluoro-2-deoxy-D-glucose positron emission tomography in detecting locally residual or recurrent nasopharyngeal carcinoma: comparison with magnetic resonance imaging.

INTRODUCTION: This prospective study was designed to elucidate the advantages and pitfalls of (18)F-FDG PET in detecting locally residual/recurrent nasopharyngeal carcinoma (NPC) in comparison with MRI. METHODS: We recruited NPC patients from two ongoing prospective trials. One is being performed to evaluate suspected local recurrence (group A) and the other to assess local treatment response 3 months after therapy (group B). Both groups received (18)F-FDG PET and head and neck MRI. The gold standard was histopathology or clinical/imaging follow-up. An optimal cut-off standardised uptake value (SUV) was retrospectively determined. RESULTS: From January 2002 to August 2004, 146 patients were eligible. Thirty-four were from group A and 112 from group B. In all, 26 had locally recurrent/residual tumours. Differences in detection rate between (18)F-FDG PET and MRI were not statistically significant in either group. However, (18)F-FDG PET showed significantly higher specificity than MRI in detecting residual tumours among patients with initial T4 disease (p=0.04). In contrast, the specificity of (18)F-FDG PET for patients with an initial T1-2 tumour treated with intracavitary brachytherapy (ICBT) was significantly lower than that for patients not treated by ICBT (72.2% vs 98.1%, p=0.003). At an SUV cut-off of 4.2, PET showed an equal and a higher accuracy compared with MRI in groups A and B, respectively. CONCLUSION: (18)F-FDG PET is superior to MRI in identifying locally residual NPC among patients with initial T4 disease but demonstrates limitations in assessing treatment response in patients with initial T1-2 disease after ICBT. A cut-off SUV is a useful index for aiding in the visual detection of locally residual/recurrent NPC.

Adult↗
PubMed2006

[18F]fluorodeoxyglucose positron emission tomography is more sensitive than skeletal scintigraphy for detecting bone metastasis in endemic nasopharyngeal carcinoma at initial staging.

PURPOSE: Bone metastasis occurs frequently in patients with endemic nasopharyngeal carcinoma (NPC). The main objective of this study is to evaluate positron emission tomography (PET) using fluorine-18-labeled fluorodeoxyglucose ([18F]FDG) and conventional skeletal scintigraphy (SS) for detecting bone metastasis at initial staging. Auxiliary objectives are to identify risk factors for bone metastasis and features associated with poor survival in patients with bone metastasis. PATIENTS AND METHODS: Patients with endemic NPC before initiation of treatment were enrolled. PET and SS were performed at initial staging and compared using McNemar's paired-sample test. Bone metastasis was considered to be present if there was any reliable evidence identified within 1 year after primary diagnosis. Multiple logistic regression and Cox's proportional hazards models were used for auxiliary objectives. RESULTS: Thirty (15%) of 202 eligible patients were found to have bone metastasis. [18F]FDG PET was found to be more sensitive than SS in the patient-based analysis (P = .006) and in the region-based analysis at the spine (P = .001). Advanced N stage was the only significant risk factor (P < .0001), and the coexistence of hepatic metastasis was a prognosticator of poor survival (P = .017). The survival was not significantly better for patients with bone metastasis undetected at primary staging than for those with initially detectable bone metastasis (P = .620). CONCLUSION: [18F]FDG PET is more sensitive than SS for detecting bone metastasis in endemic NPC at initial staging, whereas SS can be considered as supplementary in this setting.

Adult↗
PubMed2006

Differential roles of 18F-FDG PET in patients with locoregional advanced nasopharyngeal carcinoma after primary curative therapy: response evaluation and impact on management.

UNLABELLED: This prospective study compares the efficacies of whole-body (18)F-FDG PET and a conventional work-up (CWU) in evaluating the treatment response for patients with locoregional advanced nasopharyngeal carcinoma (NPC) after primary curative therapy and investigates the impact of PET on patient management. METHODS: Patients who had locoregional advanced NPC (stages III and IVa-b, staged by (18)F-FDG PET and CWU) and who had completed primary curative therapy for 3 mo were enrolled. The curative therapy consisted of concurrent chemoradiotherapy with or without induction chemotherapy. All of the patients also underwent (18)F-FDG PET and CWU to evaluate the response. The criteria for final diagnosis were based on pathology or subsequent follow-up for at least 6 mo. Rates of detection by (18)F-FDG PET and CWU and the impact on management were determined on site and patient bases, respectively. RESULTS: From January 2002 to August 2005, 131 patients with NPC were eligible, including 71 patients with stage III NPC (group A) and 60 patients with stage IVa-b NPC (group B). Twelve patients were proven to have residual tumors. (18)F-FDG PET had a higher overall sensitivity than CWU in group A (100% vs. 25%) and group B (91.7% vs. 58.3%). The overall specificity of PET was significantly higher than that of CWU in group B (97.6% vs. 91.7%; P = 0.019) but was slightly lower in group A (95.7% vs. 96.7%). The overall accuracy of PET also was significantly higher than that of CWU in group B (97.2% vs. 89.4%; P = 0.002) but was similar to that of CWU in group A (95.8% vs. 95.3%). PET resulted in management changes in 11 patients (15.4%; 11/71) in group A, with positive and negative impacts on 3 and 8 patients, respectively. In group B, the management of 26 of 60 patients (43%) was changed as a result of PET and included positive impacts on 23 patients and negative impacts on 3 patients. CONCLUSION: (18)F-FDG PET plays differential roles in patients with stage III NPC and stage IVa-b NPC after primary curative therapy. PET has higher sensitivity and specificity in evaluating the response and results in better management of patients with stage IVa-b NPC. PET has a less prominent impact on patient management but higher sensitivity in patients with stage III NPC.

Female↗
PubMed2005

Nasopharyngeal carcinoma staging by (18)F-fluorodeoxyglucose positron emission tomography.

PURPOSE: Nasopharyngeal carcinoma (NPC) has a high rate of neck lymph node and/or distant metastasis. We evaluated the value of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in staging NPC, especially in the detection of distant metastasis. METHODS AND MATERIALS: A total of 95 patients, including 85 with primary and 10 with recurrent, NPC were enrolled. Dual-phase FDG-PET was used, in addition to the conventional workup. Eighty-one patients without distant metastases underwent repeat studies 3-4 months after initial radical treatment. RESULTS: Of 14 patients with distant metastases, all had lesions detected by FDG-PET, and the conventional workup detected the metastases in only 4. Two patients had false-positive MRI findings for neck node metastasis, but the FDG-PET findings were accurate. Four patients without distant metastases on their initial workup were found to have new lesions on FDG-PET 3-4 months after initial treatment. Patients with advanced node disease had a significantly greater incidence of distant metastases on FDG-PET, especially for N3 disease. Of the 95 patients, the FDG-PET results for distant metastasis were true positive in 14 patients, false positive in 8, and true negative in 73. None of our patients had a false-negative result. For a patient base, the sensitivity and specificity of FDG-PET for distant metastasis was 100% and 90.1% (95% confidence interval 81.5-95.6%), respectively, in this study. The accuracy was 91.6% (95% confidence interval 84.1-96.3%), the positive predictive value was 63.6 (95% confidence interval 40.7-82.8%), and the negative predictive value was 100%. CONCLUSION: FDG-PET stages N and M disease of NPC more accurately and sensitively than does the conventional workup. Patients with advanced node disease, particularly N3 disease, would benefit the most from FDG-PET.

Adolescent↗
PubMed2005

The value of 18F-FDG PET in the detection of stage M0 carcinoma of the nasopharynx.

UNLABELLED: Distant metastasis is an important issue for nasopharyngeal carcinoma (NPC). The potential value of PET using 18F-FDG has not been well defined. This prospective study investigated the impact of 18F-FDG PET in NPC patients with stage M0 disease. METHODS: From April 2001 to June 2003, 140 NPC patients (118 primary and 22 primary recurrent) with stage M0 (negative results from chest radiography, liver sonography, and whole-body bone scanning) underwent 18F-FDG PET to check for distant metastases. Confirmatory MRI or CT was performed if any abnormal 18F-FDG uptake was found at distant sites. The distant lesion was confirmed pathologically, if feasible, and was followed up clinically and with imaging for at least 6 mo. RESULTS: 18F-FDG PET detected 26 true-positive metastatic sites in 18 (12.9%) of the 140 patients, among whom 14 had primary and 4 had recurrent tumors. The patient-based sensitivity and specificity of 18F-FDG PET for distant metastases were 100% and 86.9%, respectively. Mediastinal lymph nodes (n = 8) were the most common sites, followed by lung, liver, and bone (n = 5 each) and by other lymph nodes (n = 3). In patients with primary tumors, advanced nodal status (N2-3) was a statistically significant variable associated with development of distant metastases (P = 0.044). For recurrent NPC, neither age, sex, initial tumor stage, grade of differentiation, nor nodal stage showed a statistically significant difference between patients with and patients without distant metastases. CONCLUSION: 18F-FDG PET is valuable in avoiding aggressive locoregional radiotherapy in some NPC patients by the revelation of occult distant metastases, especially in patients with primary disease at a nodal stage of N2-3.

Adolescent↗
PubMed2005

Staging of untreated squamous cell carcinoma of buccal mucosa with 18F-FDG PET: comparison with head and neck CT/MRI and histopathology.

UNLABELLED: This prospective, nonrandomized, case-control study evaluated the impact of (18)F-FDG PET in staging untreated squamous cell carcinoma of the buccal mucosa (BSCC) and compared the results with CT/MRI and histopathology. METHODS: Between January 2002 and April 2004, 102 untreated BSCC patients with cM0 (no evidence of distant metastatic focus on chest radiograph, liver ultrasonograph, and bone scan) were enrolled with either conventional work-up (CWU, n = 51) or PET (CWU+PET, n = 51). All were monitored for at least 6 mo. The comparative diagnostic efficacies of PET and CT/MRI were evaluated using the area under the receiver-operating-characteristic curve (AUC). The primary endpoint was the percentage reduction in futile surgery (preoperative detection of distant metastatic lesions). The secondary endpoint was the 2-y cumulative recurrence rate among study participants (with PET) compared with that of comparable control subjects (without PET). RESULTS: Significant benefits of PET compared with those of CT/MRI for BSCC patients were in the detection of locoregional (AUC, 0.973 vs. 0.928; P = 0.026), regional (AUC, 0.939 vs. 0.837; P = 0.026), and level II (AUC, 0.974 vs. 0.717; P = 0.02) lymph nodes. Two percent (1/51) of the patients experienced a reduction in futile surgery in the CWU+PET group compared with 0% (0/51) in the CWU group. However, no statistical difference was found in the 2-y locoregional control rate between the CWU and the CWU+PET groups. CONCLUSION: The role of (18)F-FDG PET for BSCC with cM0 is limited. Although PET is superior to CT/MRI in identifying cervical nodal metastases, it does not improve locoregional recurrence.

Adult↗
PubMed2005

18F-FDG PET and CT/MRI in oral cavity squamous cell carcinoma: a prospective study of 124 patients with histologic correlation.

UNLABELLED: Accurate evaluation of primary tumors and cervical lymph node status of squamous cell carcinoma (SCC) of the oral cavity is important to treatment planning and prognosis prediction. In this prospective study, we evaluated the use of 18F-FDG PET, CT/MRI, and their visual correlation for the identification of primary tumors and cervical nodal metastases of SCC of the oral cavity with histologic correlation. METHODS: One hundred twenty-four patients with pathologically proven diagnoses of oral cavity SCC underwent 18F-FDG PET and CT/MRI within 2 wk before surgery. We interpreted 18F-FDG PET, CT/MRI, and visually correlated 18F-FDG PET and CT/MRI separately to assess the primary tumors and their regional lymph node status. We recorded lymph node metastases according to the neck level system of imaging-based nodal classification. Histopathologic analysis was used as the gold standard for assessment of the primary tumors and lymph node involvement. We analyzed differences in sensitivity and specificity among the imaging modalities using the McNemar test. The receiver-operating-characteristic (ROC) curve and calculation of the area under the curve were used to evaluate their discriminative power. RESULTS: The accuracy of 18F-FDG PET, CT/MRI, and their visual correlation for the identification of primary tumors was 98.4%, 87.1%, and 99.2%, respectively. The sensitivity of 18F-FDG PET for the identification of nodal metastases on a level-by-level basis was 22.1% higher than that of CT/MRI (74.7% vs. 52.6%, P < 0.001), whereas the specificity of 18F-FDG PET was 1.5% lower than that of CT/MRI (93.0% vs. 94.5%, P = 0.345). The sensitivity and specificity of the visual correlation of 18F-FDG PET and CT/MRI were 3.2% and 1.5% higher than those of 18F-FDG PET alone (77.9% vs. 74.7%, P = 0.25; 94.5% vs. 93.0%, P = 0.18, respectively). The area under the curve obtained from the ROC curve showed that 18F-FDG PET was significantly superior to CT/MRI for total nodal detection (0.896 vs. 0.801, P = 0.002), whereas the visual correlation of 18F-FDG PET and CT/MRI was modestly superior to 18F-FDG PET alone (0.913 vs. 0.896, P = 0.28). CONCLUSION: 18F-FDG PET is superior to CT/MRI in the detection of cervical status of oral cavity SCC. The sensitivity of 18F-FDG PET for the detection of cervical nodal metastasis on a level-by-level basis was significantly higher than that of CT/MRI, whereas their specificities appeared to be similar. Visual correlation of 18F-FDG PET and CT/MRI showed a trend of increased diagnostic accuracy over 18F-FDG PET alone but without a statistically significant difference, and its sensitivity was still not high enough to replace pathologic lymph node staging based on neck dissection.

Adult↗
PubMed2004

Are dual-phase 18F-FDG PET scans necessary in nasopharyngeal carcinoma to assess the primary tumour and loco-regional nodes?

PURPOSE: This prospective study aimed to investigate the efficacy of dual-phase positron emission tomography (PET) in evaluating the loco-regional status of nasopharyngeal carcinoma (NPC). METHODS: Eighty-four patients with newly diagnosed NPC and a fasting serum glucose level of <200 mg/dl were enrolled. [18F]fluoro-2-deoxy-D-glucose (18F-FDG) PET studies (at 40 min and 3 h after injection of 370 MBq 18F-FDG) and head and neck magnetic resonance imaging (MRI) were performed within 1 week. Diagnostic criteria for NPC comprised the histopathological findings, the joint judgments of the research team and the post-treatment outcome. Each lesion's maximum standardised uptake value (SUV) and retention index were obtained. SUV data were evaluated using a paired t test. Receiver operating characteristic curves and calculation of the area under the curve (AUC) determined the discriminative power. RESULTS: 18F-FDG PET was significantly superior to MRI in identifying lower neck NPC nodal metastasis (AUC: 1 vs 0. 972, P=0.046) and overall loco-regional metastases (AUC: 0.985 vs 0.958, P=0.036). However, 18F-FDG PET was similar to MRI in detecting primary tumour, as well as retropharyngeal, upper neck and supraclavicular nodal metastases. There was no significant difference between early phase (40 min) and delayed phase (3 h) 18F-FDG PET in the detection of primary tumours (accuracy: 100% vs 100%) or loco-regional nodal metastasis (AUC: 0.984 vs 0.985, P=0.834). CONCLUSION: 18F-FDG PET is superior to MRI in identifying lower neck nodal metastasis of NPC. Additional 3-h 18F-FDG PET contributes no further information in the detection of primary tumours or loco-regional metastatic nodes in untreated NPC patients.

Adolescent↗
PubMed2004

Nodal metastases of nasopharyngeal carcinoma: patterns of disease on MRI and FDG PET.

The patterns of nodal spread of nasopharyngeal carcinoma (NPC) have an important influence on treatment planning, but have not yet been fully addressed. We prospectively used MRI and FDG PET to document the patterns of nodal spread in NPC. One hundred and one patients with newly diagnosed NPC were studied with MRI and FDG PET. On MRI, nodes were considered as metastatic according to criteria regarding size, the presence of nodal necrosis, and extracapsular spread. FDG PET images were interpreted visually, and nodes were considered metastatic if they showed prominent FDG uptake against the background. Nodal metastases were found in 89 of our 101 patients. Analysis of the distributions of nodal metastases in these 89 patients showed that retropharyngeal nodes were less frequently involved than cervical nodes (82.0% vs 95.5%). The vast majority of cervical nodal metastases were to the internal jugular chain, including nodes at levels II, III, and IV, with decreasing incidences of 95.5%, 60.7%, and 34.8%, respectively. Level V nodal involvement was found in 27% of patients. Supraclavicular fossa nodal metastases were not uncommon and occurred in 22.5% of patients. Skip metastases in the lower-level nodes or supraclavicular fossa nodes occurred in 7.9% of patients. Mediastinal and abdominal metastatic adenopathy was present in 4.5% and 3.4% of patients, respectively, and was associated with advanced nodal metastasis in the supraclavicular fossa. Level VI (2.2%), level VII (1.1%), submandibular (2.2%), and parotid (3.4%) nodal metastases were uncommon and were always associated with advanced ipsilateral nodal metastases of the neck. We conclude that the combined use of FDG PET and MRI can comprehensively depict the pattern of nodal metastasis in NPC patients. Nodal metastases principally affected level II nodes, from which lymphatic spread extended down in an orderly manner to involve level III, level IV, and the supraclavicular fossa nodes, or extended posteriorly to involve level V nodes. The frequency of skip metastases was 7.9%. Distant spread to mediastinal or abdominal nodes was found in 3-5% of patients, usually in association with supraclavicular nodal metastases.

Adolescent↗
PubMed2004

Clinical usefulness of 18F-FDG PET in nasopharyngeal carcinoma patients with questionable MRI findings for recurrence.

UNLABELLED: It has been reported that 18F-FDG PET is highly sensitive for the detection of recurrent head-and-neck cancer. The objective of our prospective study was to validate the ability of this technique to detect the presence of tumors in primary, nodal, and distant sites as well as to assess its overall clinical usefulness in patients with questionable MRI findings for residual or recurrent nasopharyngeal carcinoma (NPC). METHODS: From January 2002 to October 2003, a group of 37 NPC patients whose postradiation follow-up MRI examination showed questionable residual or recurrent disease was assessed with 18F-FDG PET. 18F-FDG PET was interpreted visually. Disease at primary, nodal, and distant sites was assessed. The final diagnosis was confirmed histopathologically or with clinical and imaging follow-up of at least 6 mo. RESULTS: Our results showed that the sensitivity and specificity of 18F-FDG PET for the detection of recurrent NPC were 91.6% and 76.0%, respectively, at the primary site; 90.0% and 88.9%, respectively, at nodal sites; and 100% and 90.6%, respectively, at distant sites. The overall sensitivity and specificity were 89.5% and 55.6%, respectively. Among the 37 patients, 18F-FDG PET added significant information to the MRI findings in 18, including offering true-negative findings in 10, revealing unexpected small metastatic adenopathy in 3, and disclosing distant metastatic foci in 5. CONCLUSION: 18F-FDG PET is highly sensitive and moderately specific for the detection of recurrent NPC in patients with questionable MRI findings. Overall, 18F-FDG PET appears to add significant information to MRI findings in about half of the NPC patients whose MRI examination shows questionable tumor recurrence.

Adolescent↗
PubMed2003

Diffuse cutaneous plasmacytomas demonstrated on gallium-67 imaging.

Gallium-67 scanning is a useful tool to search for infectious foci and malignant tumors. Multiple myeloma is one clinical indication for gallium-67 tumor survey. Here, we report a rare case of diffuse multiple cutaneous plasmacytomas from recurrent multiple myeloma, demonstrated by whole-body gallium-67 scan.

Female↗