10 results on '"Homer A, Macapinlac"'
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2. Laparoscopic extraperitoneal para-aortic lymphadenectomy in locally advanced cervical cancer1
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Robert L. Coleman, Elizabeth D. Euscher, Kathleen M. Schmeler, Homer A. Macapinlac, Lois M. Ramondetta, Pedro T. Ramirez, Pamela T. Soliman, Mark F. Munsell, Michael Frumovitz, and Anuja Jhingran
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Cervical cancer ,Cancer Research ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Cancer ,Magnetic resonance imaging ,medicine.disease ,Endoscopy ,Metastasis ,Oncology ,Positron emission tomography ,medicine ,Lymphadenectomy ,Radiology ,Stage (cooking) ,business - Abstract
BACKGROUND: Failure to detect metastasis to para-aortic nodes in patients with locally advanced cervical cancer leads to suboptimal treatment. No previous studies have prospectively compared positron emission tomography (PET)/computed tomography (CT) with laparoscopic extraperitoneal staging in the evaluation of para-aortic lymph nodes. METHODS: Sixty-five patients were enrolled; 60 were available for analysis. Patients with stage IB2-IVA cervical cancer without evidence of para-aortic lymphadenopathy on preoperative CT or magnetic resonance imaging (MRI) were prospectively enrolled. All patients underwent preoperative PET/CT. Laparoscopic extraperitoneal lymphadenectomy was performed from the common iliac vessels to the left renal vein. RESULTS: The median age at diagnosis was 48 years (range, 23-84). The median operative time was 140 minutes (range, 89-252). The median blood loss was 22.5 mL (range, 5-150). The median length of hospital stay was 1 day (range, 0-4). The median number of lymph nodes retrieved was 11 (range, 1-39). Fourteen (23%) patients had histopathologically positive para-aortic nodes. Of the 26 patients with negative pelvic and para-aortic nodes on PET/CT, 3 (12%) had histopathologically positive para-aortic nodes. Of the 27 patients with positive pelvic but negative para-aortic nodes on PET/CT, 6 (22%) had histopathologically positive para-aortic nodes. The sensitivity and specificity of PET/CT in detecting positive para-aortic nodes when nodes were negative on CT or MRI were 36% and 96%, respectively. Eleven (18.3%) patients had a treatment modification based on surgical findings. CONCLUSIONS: Laparoscopic extraperitoneal para-aortic lymphadenectomy is safe and feasible. Surgical staging of patients with locally advanced cervical cancer should be considered before planned radiation and chemotherapy. Cancer 2011. © 2010 American Cancer Society. more...
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- 2010
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3. Attenuation correction of PET cardiac data with low-dose average CT in PET/CT
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Tinsu Pan, Zhongxing Liao, Hui Liu, Mylene T. Truong, Homer A. Macapinlac, Dershan Luo, Martha Mar, Gregory W. Gladish, Jeremy J. Erasmus, Pai Chun M. Chi, and Osama Mawlawi
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Fluorodeoxyglucose ,medicine.medical_specialty ,PET-CT ,medicine.diagnostic_test ,business.industry ,Image registration ,General Medicine ,Positron emission tomography ,medicine ,Medical imaging ,Radiology ,Tomography ,Computed radiography ,Nuclear medicine ,business ,Correction for attenuation ,medicine.drug - Abstract
We proposed a low-dose average computer tomography (ACT) for attenuation correction (AC) of the PET cardiac data in PET/CT. The ACT was obtained from a cine CT scan of over one breath cycle per couch position while the patient was free breathing. We applied this technique on four patients who underwent tumorimaging with F 18 - FDG in PET/CT, whose PET data showed high uptake of F 18 - FDG in the heart and whose CT and PET data had misregistration. All four patients did not have known myocardiac infarction or ischemia. The patients were injected with 555 – 740 MBq of F 18 - FDG and scanned 1 h after injection. The helical CT (HCT) data were acquired in 16 s for the coverage of 100 cm . The PET acquisition was 3 min per bed of 15 cm . The duration of cine CT acquisition per 2 cm was 5.9 s . We used a fast gantry rotation cycle time of 0.5 s to minimize motion induced reconstruction artifacts in the cine CTimages, which were averaged to become the ACT images for AC of the PET data. The radiationdose was about 5 mGy for 5.9 s cine duration. The selection of 5.9 s was based on our analysis of the respiratory signals of 600 patients; 87% of the patients had average breath cycles of less than 6 s and 90% had standard deviations of less than 1 s in the period of breath cycle. In all four patient studies, registrations between the CT and the PET data were improved. An increase of average uptake in the anterior and the lateral walls up to 48% and a decrease of average uptake in the septal and the inferior walls up to 16% with ACT were observed. We also compared ACT and conventional slow scan CT (SSCT) of 4 s duration in one patient study and found ACT was better than SSCT in depicting average respiratory motion and the SSCT images showed motion-induced reconstruction artifacts. In conclusion, low-dose ACT improved registration of the CT and the PET data in the heart region in our study of four patients. ACT was superior than SSCT for depicting average respiration motion in a patient study. more...
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- 2006
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4. Early effects of imatinib mesylate on the expression of insulin-like growth factor binding protein-3 and positron emission tomography in patients with gastrointestinal stromal tumor
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A. Salvado, Limei Hu, Robert S. Benjamin, Jonathan C. Trent, Jheri Dupart, Homer A. Macapinlac, Raphael E. Pollock, Latha Ramdas, Ellen Taylor, James L. Abbruzzese, Kelly K. Hunt, and Wei Zhang
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Cancer Research ,Cell Survival ,Gastrointestinal Stromal Tumors ,Antineoplastic Agents ,Apoptosis ,Piperazines ,Western blot ,Biopsy ,medicine ,Humans ,Stromal tumor ,neoplasms ,medicine.diagnostic_test ,GiST ,business.industry ,Gene Expression Profiling ,Cancer ,Sarcoma ,Imatinib ,medicine.disease ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,Insulin-Like Growth Factor Binding Proteins ,Radiography ,Insulin-Like Growth Factor Binding Protein 3 ,Pyrimidines ,Imatinib mesylate ,Oncology ,Positron-Emission Tomography ,Benzamides ,Imatinib Mesylate ,Cancer research ,business ,medicine.drug - Abstract
BACKGROUND. Imatinib has demonstrated marked clinical efficacy against gastrointestinal stromal tumor (GIST). Microarray technology, real-time polymerase chain reaction (PCR) validation, and fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging were used to study the early molecular effects of imatinib antitumor activity in GIST. METHODS. After exposure of sensitive and resistant sarcoma cell lines to imatinib for 24 to 48 hours, the changes in gene expression were evaluated using a 1146 unique pathway array with Western blot validation. Real-time PCR was used to confirm changes in gene expression in human GIST samples (preimatinib biopsy and postimatinib surgical specimen after 3–7 days of therapy). FDG-PET was performed to correlate radiographic findings with the effects of imatinib on gene expression in GIST. RESULTS. In all, 55 genes demonstrated a ≥ 2-fold change after imatinib treatment of the GIST882 cells. Among these genes there was up-regulation of insulin-like growth factor binding protein-3 (IGFBP-3), a protein that modulates proliferation and apoptosis. Western blot analysis confirmed the increase of IGFBP-3 only in imatinib-sensitive GIST882 cells. Up to a 7-fold induction (49% mean increase; P = .08) of IGFBP-3 mRNA was found in tumor samples from patients with low residual FDG uptake, whereas there was an up to 12-fold reduction (−102% mean decrease; P = .03) in IGFBP-3 in those patients with high residual FDG uptake after imatinib therapy. CONCLUSIONS. In the current study, imatinib appears to regulate numerous genes and specifically induces IGFBP-3 in GIST cells and tumor samples. IGFBP-3 levels also were found to be inversely correlated with residual FDG uptake in GIST patients early in imatinib therapy. These initial observations suggest that IGFBP-3 is an important early marker of antitumor activity of imatinib in GIST. Cancer 2006. © 2006 American Cancer Society. more...
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- 2006
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5. Target Detection and the Prefrontal Cortex. A PET Scan Study of the P300 Event-Related Potential
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Ruth A. Reinsel, Vladimir A. Feshchenko, Steven M. Larson, Robert A. Veselis, David Silbersweig, Emily Stern, Stanley J. Goldsmith, Homer A. Macapinlac, G. R.Di Resta, Osama Mawlawi, Ronald G. Blasberg, Brad Beattie, and Ronald D. Finn more...
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Adult ,Male ,business.industry ,General Neuroscience ,Prefrontal Cortex ,Event-Related Potentials, P300 ,General Biochemistry, Genetics and Molecular Biology ,Acoustic Stimulation ,History and Philosophy of Science ,Event-related potential ,Cerebrovascular Circulation ,Humans ,Medicine ,Prefrontal cortex ,business ,Neuroscience ,Tomography, Emission-Computed - Published
- 1995
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6. Integrated PET/CT in Head and Neck Cancer: Controversies and Challenges
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David Goldenberg, F. Christopher Holsinger, Homer A. Macapinlac, Richard Wong, and David Myssiorek
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Otorhinolaryngology ,Surgery - Published
- 2009
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7. A comparative study on the value of dual tracer PET/CT to evaluate breast cancer. 18F-FDG PET/CT images reveal a focal hypermetabolic focus of the primary tumor (upper panel), whereas 11C-choline PET/CT images reveal only a focal hypermetabolic focus in t
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Hitoshi Tsuda, Takayuki Kinoshita, Takeshi Murano, Takashi Terauchi, Homer A. Macapinlac, Hiromitsu Daisaki, Ukihide Tateishi, Sadako Akashi-Tanaka, and Daisuke Kano
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Cancer Research ,medicine.medical_specialty ,PET-CT ,Focus (geometry) ,business.industry ,General Medicine ,medicine.disease ,Primary tumor ,11c choline pet ct ,Breast cancer ,Oncology ,Dual tracer ,Medicine ,Fdg pet ct ,Radiology ,business ,Nuclear medicine - Published
- 2012
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8. SU-GG-I-135: Average CT in Colorectal Cancer PET Studies
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Tinsu Pan, P Chi, Adam C. Riegel, Osama Mawlawi, E. Tonkopi, Homer A. Macapinlac, and Eric M. Rohren
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medicine.medical_specialty ,medicine.diagnostic_test ,Colorectal cancer ,business.industry ,Concordance ,Cancer ,General Medicine ,For Attenuation Correction ,medicine.disease ,Metastasis ,Lesion ,Positron emission tomography ,medicine ,Radiology ,medicine.symptom ,Radiation treatment planning ,Nuclear medicine ,business - Abstract
Purpose: To assess the effect of average CT (ACT) used for attenuation correction of PET data on SUVmax and gross tumor volume (GTV) in liver lesions of colorectal cancer patients. Method and Materials: We studied 34 colorectal cancer patients with metastasis in the liver. A routine PET/CT scan was immediately followed by a cine CT scan of the liver region for ACT. Patients were free‐breathing during the helical CT (HCT) and ACT acquisitions. Both HCT and ACT were used for attenuation correction of the PET data. 59 liver lesions were included in the study and SUVmax for each lesion was measured on PETHCT and PETACT. Both PETdata sets were imported to Pinnacle3 7.6 treatment planning system. GTVs for PETimages were generated based on the SUV thresholds, normally used for assessing tumor response to therapy. Percentage volume change, centroid shift and concordance index were defined for each lesion. Results: 67% of the studies showed respiratory artifacts in PETHCT while 15% demonstrated a difference in SUVmax above 20%. The effect of misregistration between HCT and PET data was more evident for smaller lesions with the most pronounced case showing a 29% increase in SUVmax for PETACT, 246% increase in GTV, 2mm shift in GTV centroid location and concordance index value of 0.34. We analyzed correlation between the variations and the lesion size with a non‐paired t‐test at 0.05 p‐value level. The means of concordance indexes in two distributions of the lesions normalized to their size (less and greater than 5cm3) were shown to be significantly different (p=0.007). Conclusion: ACT is effective in improving the registration between the CT and PET data in PET/CT, which is important when using PETimages for treatment planning. Misregistration is more pronounced for small lesions and should be considered in the generation of the GTVs. more...
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- 2008
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9. SU-FF-I-99: Effect of Average CT On Quantifying PET Imaging in Esophageal Cancer
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Homer A. Macapinlac, Tinsu Pan, H. D. Yeung, E. Tonkopi, Osama Mawlawi, and P Chi
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Thorax ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Cancer ,General Medicine ,For Attenuation Correction ,Esophageal cancer ,medicine.disease ,Positron emission tomography ,Medical imaging ,medicine ,Radiology ,Nuclear medicine ,business ,Prospective cohort study ,Correction for attenuation - Abstract
Purpose: To quantify the effect of average CT (ACT) on improving the registration of the PET and CT data (Pan et al, JNM 05) in a prospective study of esophageal cancer patients. Method and Materials: We investigated 52 studies of esophageal cancer patients who underwent a routine PET/CT scan followed by a cine CT scan for ACT. The patients were injected with 555–740 MBq of 18F‐FDG and scanned 1 hour after injection. A helical CT (HCT) scan was acquired in 16 s over 90 cm coverage followed by a PET scan of 3 min per bed and a cine CT scan of the thorax for ACT. Patients were free breathing during the HCT and ACT scans, the cine duration was 5.9 s to capture at least one breath cycle. Both HCT and ACT were used for attenuation correction (AC) of PET data. Misalignment between the PET and CT at the level of the diaphragm and the maximum standardized uptake values (SUVmax) of the esophageal tumor were used to assess the difference between the two attenuation correction techniques. Results: 9 patients (17%) showed over 20% increase or decrease in SUVmax due to misregistration between the HCT and PET data with one patient showing a 50% increase in SUVmax. The misalignment at the diaphragm level with the magnitude of over 1 cm was detected in 32 patients (62%) with an average value of 15.1±6.5 mm. ACT was effective in removing the misalignment in 23 cases (44%). Additional radiation dose was 5–10 mGy with an increase in processing time of 5 min. Conclusion: ACT is effective in improving the registration between the CT and the PET data in PET/CT, and is able to improve AC of PET data in 44% of the esophageal cancer studies. more...
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- 2007
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10. SU-FF-J-102: A New Method for Improving PET and CT Registration in the Thorax On PET/CT
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H. Liu, Tinsu Pan, Peter A Balter, Homer A. Macapinlac, Radhe Mohan, Y. Erdi, Sadek Nehmeh, S. Hunjan, Osama Mawlawi, Karl Prado, and Dershan Luo
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Thorax ,medicine.medical_specialty ,PET-CT ,medicine.diagnostic_test ,business.industry ,Computed tomography ,General Medicine ,Breathing cycle ,Helical ct ,medicine ,Medical imaging ,Radiology ,Rotation cycle ,Ct imaging ,business ,Nuclear medicine - Abstract
Purpose: We propose a new method of acquiring the CT data to improve the registration of the PET and CT data in imaging the thorax on PET/CT. Method and Materials: In a conventional PET/CT acquisition, the CT and PET data are acquired at two different breathing states. There is an inherent mismatch of the PET and CT because the temporal resolutions of the PET and CT are not matched. We have proposed a new method of acquiring the average CT (ACT) data from the 4D‐CT imaging to provide the CT data consistent with the PET data on temporal resolution. We have applied this approach to one esophagus and seven lung patients. The helical CT data were taken helically at 120 kV, 300 mA, pitch 1.35:1, 8×2.5 mm collimation, and 0.5 s rotation and the patients were instructed to hold a breath at mid‐expiration during the HCT of the thorax. The PET acquisition was 3 mins per bed. The 4D‐CT data of the thorax were taken right after the PET/CT study at 120 kV, 50 to 150 mA, cine duration of one breathing cycle plus 1 s, 8×2.5 mm collimation, and 0.5 s CT rotation cycle. We compared the registration between the ACT and PET data, and the registration between the HCT and PET data. Results: The PET and ACT data were all consistent at all tumor locations. The mismatch between the HCT and PET data were significantly improved on 4 out of the 8 patients with the ACT data over the HCT data.. Conclusion: We have proposed the use of the ACT to improve the registration of the PET and CT data, and demonstrated a significant improvement in lesion localization between the PET and ACT data. more...
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- 2005
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