Comparison of Dosimetry and Gamma Camera Methods for Evaluation of Biodistribution Prior to Administration of the Therapeutic Dose of Tositumomab and Iodine I 131 Tositumomab (Bexxar Therapeutic Regimen)

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4916-4916
Author(s):  
Thierry J. Horner ◽  
Jeffry A. Siegel ◽  
Roxanne C. Jewell ◽  
Gary J. Lunger ◽  
Nancy L. Young ◽  
...  
Keyword(s):  
Therapeutic Dose ◽  
Gamma Camera ◽  
Visual Assessment ◽  
Therapeutic Regimen ◽  
Low Grade ◽  
Time Points ◽  
Post Marketing ◽  
The Mean ◽  
Total Body

Abstract Abstract 4916 Introduction: The Bexxar® Therapeutic Regimen for relapsed/refractory follicular lymphoma (FL) is administered in 2 steps: a dosimetric dose and a therapeutic dose. Radioactive counts, obtained from sequential gamma camera scans of the whole body at several time points after the dosimetric dose, determine the patient (pt)-specific clearance (total body residence time, TBRT) and, along with pt body size, allow determination of the prescribed activity (PA) of the therapeutic dose. Pts do not receive the therapeutic dose if TBRT is outside 50 to 150 hrs and/or gamma camera images show altered biodistribution. TBRT is used to calculate the mCi of I-131 (PA) required to deliver the appropriate therapeutic dose of 65 or 75 cGy to the total body, depending on platelet count. Our aims were 1) to evaluate an alternative, inexpensive sodium iodide probe (probe) detector-based method of measuring radioactive counts for determination of TBRT and 2) to evaluate the clinical benefit of visually assessing gamma camera images for altered biodistribution. Methods: We retrospectively compared probe and gamma camera methods from a phase II study (RIT-II-001) and evaluated altered biodistribution assessed by gamma camera images from a post-marketing observational study. Forty-one of 47 FL pts enrolled in RIT-II-001 from December 1995 to November 1996 were included in the retrospective analysis of TBRT and PA. Pts received a median of 5 prior chemotherapies (range 2–13). Thirty of 41 (73%) pts had low-grade B-NHL, 90% had stage III or IV disease, 51% had bone marrow involvement, 88% had an International Prognostic Index score ≥ 2, and 16 of 34 (47%) pts had bulky disease >500 g. Dosimetry analysis was performed at 3 time points (Day 0; Day 2, 3, or 4; and Day 6 or 7) after dosimetric dose, as currently required for determining PA. The PAs of the therapeutic dose using TBRTs derived from probe and gamma camera counts were compared. Also, we retrospectively evaluated cases of altered biodistribution in an observational post-marketing study (BEX114606) of 2,649 pts who received a dosimetric dose from June 2003 to February 2010. Dosimetry and gamma camera images were independently reviewed from reported cases of altered biodistribution to evaluate the clinical benefit of visually assessing gamma camera images. Results: The mean TBRTs from the clinical study were 94.5 and 95.0 hrs from the probe and gamma camera methods, respectively, and individual TBRTs were highly correlated (r = 0.98). The mean PAs of the therapeutic dose, derived from probe and gamma camera TBRTs, were 85.8 mCi and 85.3 mCi, respectively. The point estimate for the ratio of the PA was 0.995 and the 90% CI (0.984, 1.006) was well within the typical range of 0.80 to 1.25 for demonstrating bioequivalence. The observational study found that only 5 of 2,649 (0.2%) pts did not receive the therapeutic dose due to suspected altered biodistribution. Dosimetry data and gamma camera images were available for 3 pts. Independent review confirmed that all 3 pts had accurately determined TBRTs, but only 1 pt had confirmed altered biodistribution by visual assessment of gamma camera images and TBRTs. Conclusion: TBRTs derived from probe and gamma camera counts were highly comparable. Thus, the probe and gamma camera methods to determine TBRT and calculate the PA of the therapeutic dose of Bexxar appear equivalent. Altered biodistribution prevented only 5 of 2,649 (0.2%) pts from receiving the therapeutic dose of Bexxar. Only 1 pt (0.04%) was independently confirmed to have altered biodistribution by visual assessment of gamma camera images, consistent with the TBRT. Therefore, visual assessment of gamma camera images added no benefit beyond TBRT in determining whether to administer the therapeutic dose of Bexxar. These data indicate that either sequential probe or gamma camera-based dosimetry is sufficient for determining whether to administer the therapeutic dose, and that visual assessment of gamma camera images does not appear to be necessary to detect the rare instance of an altered biodistribution. Disclosures: Horner: GlaxoSmithKline: Employment. Off Label Use: The BEXXAR therapeutic regimen (Tositumomab and Iodine I 131 Tositumomab) is indicated for the treatment of patients with CD20 antigen-expressing relapsed or refractory, low grade, follicular, or transformed non-Hodgkin's lymphoma, including patients with Rituximab-refractory non-Hodgkin's lymphoma. Siegel: GlaxoSmithKline: Consultancy. Jewell: GlaxoSmithKline: Employment. Lunger: GE Healthcare: Employment. Young: GlaxoSmithKline: Employment. Wynne: GlaxoSmithKline: Employment. Williams: GlaxoSmithKline: Employment. Lin: GlaxoSmithKline: Employment. Kaminski: GlaxoSmithKline: Patents & Royalties, Research Funding. Wahl: GlaxoSmithKline: Consultancy, Patents & Royalties; Nihon Medi Physics: Consultancy; Spectrum Pharmaceuticals: Consultancy; Naviscan PET systems: Consultancy; Threshold Pharmaceuticals: Equity Ownership. Vleisides: GlaxoSmithKline: Employment.

A Method for Subtraction of the Extrarenal “Background” in Dynamic 131J-Hippurate Renoscintigraphy

1979 ◽  
Vol 18 (01) ◽  
pp. 36-39
Author(s):  
J. Liniecki ◽  
M. Surma ◽  
Mlodkowska Ewa
Keyword(s):  
Background Subtraction ◽  
Count Rate ◽  
Gamma Camera ◽  
Left Kidney ◽  
Coefficients Of Variation ◽  
Activity Curve ◽  
The Mean ◽  
The Right ◽  
Sufficient Precision

SummaryUsing a Toshiba GC-401 gamma camera with MDS computer Trinary a new method was developed for subtracting the extrarenal (extracanalicular) “background” from the count rate recorded over the kidneys after intravenous administration of 131I-hippurate. Mean subtraction factors of the “blood” activity curve were calculated from a study of 27 patients who were given 51Cr-HSA for purposes of conventional renography with “background” subtraction.The values of the mean subtraction factors FR>L for the right and left kidney, by which a blood count rate should be multiplied amounted to 0.86 ± 0.12 and 0.79 ± 0.13, respectively.A comparison of the coefficients of variation of the pure renal signal when mean vs. individually determined subtraction factors were used, and the verification of the method in unilaterally nephrectomized patients have demonstrated that determination of the factors, FR?L, for each patient individually is not required and sufficient precision can be obtained by using the method and factors reported in this study.

Significance of illite crystallinity and bo values of K-white mica in lowgrade metamorphic rocks, North Hill End Synclinorium, New South Wales, Australia

1985 ◽  
Vol 49 (352) ◽  
pp. 357-364 ◽  
Author(s):  
R. Offler ◽  
E. Prendergast
Keyword(s):  
Early Carboniferous ◽  
Geothermal Gradient ◽  
White Mica ◽  
Low Grade ◽  
Illite Crystallinity ◽  
The North ◽  
South Wales ◽  
The Mean ◽  
Two Populations

AbstractA study of low-grade metamorphism in late Silurian to early Carboniferous rocks in the North Hill End Synclinorium and adjacent anticlinoria has been made by the determination of illite crystallinity and bo values of K-white mica in eighty slates and phyllites. Illite crystallinity values vary from 0.40 Δ°2θ on the Molong Anticlinorium to 0.12 Δ°2θ within the axis of the synclinorium, suggesting anchizonal to epizonal metamorphic conditions. This is in agreement with previous observations on Ca-Al-hydrosilicate assemblages which indicated a change from prehnite-pumpellyite facies in the anticlinoria adjacent to the synclinorium to middle greenschist facies in the axis. Local variations in crystallinity are attributed to variation in ak+ in fluids migrating along cleavage zones.The mean bo value obtained from the pelites is 9.017 Å (σn = 0.008; n = 80) which is in close agreement with that obtained from part of the adjacent Capertee Anticlinorium (x̄ = 9.019 Å; σn = 0.007; n = 52). However, ‘t’ tests indicate that two bo populations are present in the synclinorium (x̄ = 9.019 and 9.022 Å), with the lower values concentrated in the southern portion of this structure. The two populations are considered to be the result of slightly different metamorphic conditions prevailing during the deformation of the rocks in the synclinorium. A higher geothermal gradient affecting rocks giving the lower bo values is attributed to the presence of granitoids at shallower depths than elsewhere in the synclinorium.

Prediction of the body composition of live cattle

1972 ◽  
Vol 78 (3) ◽  
pp. 505-508 ◽  
Author(s):  
D. A. Little ◽  
J. G. Morris
Keyword(s):  
Body Composition ◽  
Tritiated Water ◽  
Live Weight ◽  
The Body ◽  
Equilibration Time ◽  
Live Animal ◽  
Free Weight ◽  
The Mean ◽  
Total Body

SUMMARYTwo methods of determining body composition in live cattle have been compared with the composition of the cattle as determined by chemical analysis. Total body water (TBW) was estimated from tritiated water (TOH) dilution, and circulating redcell volume (RCV) estimated from measurements of plasma volume and haematocrit. TBW was very closely related to fat-free weight and fat weight as a percentage of live weight (LW) in eight cattle ranging from 3 to 34% fat. TOH space was more precise than RCV in the estimation of the various chemical fractions of the live animal.TOH injected intravenously equilibrated with ruminal water in 8–10 h; one could be confident that equilibration had occurred 10 h after injection, and equilibration time was not affected by previous restriction of feed and water. The mean biological half life of TOH was 4·2 ± 0·4 days. Equations are presented for the practical determination of the various compartments.

FDG-PET May Be Helpful in the Determination of Transformation to an Aggressive Subtype in Low-Grade Lymphoma.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1927-1927
Author(s):  
Lale Kostakoglu ◽  
Stanley J. Goldsmith ◽  
Amy Chadburn ◽  
Erez Vidan ◽  
Michael Schuster ◽  
...  
Keyword(s):  
Pet Imaging ◽  
Fdg Pet ◽  
Low Grade ◽  
Indolent Lymphoma ◽  
Mean Values ◽  
Fdg Uptake ◽  
Significant Difference ◽  
The Mean ◽  
Indolent Disease

Abstract The therapeutic management of the patient with transformed low-grade lymphoma is quite different from those with pure indolent disease. In cases of transformation FDG uptake characteristics may help identify an area of transformation in indolent disease and thereby impact management. Our objective was to evaluate the potential of FDG-PET imaging in the determination of transformation Methods: A total of 60 patients with low-grade lymphoma (48 patients) and those with known transformation to DLCL (12 patients) underwent FDG-PET imaging prior to therapy. In the indolent group, 27 patients were diagnosed with a follicular histology and 11 with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and 10 were with marginal zone lymphoma. A total of 370 lesions were evaluated and SUV’s were obtained for all visualized lesions. Mean values were calculated on a patient and total site basis. Additionally, mean SUV values were calculated for lesions with the highest SUV’s, in groups with indolent and transformation histology. Results: Results are summarized in the Table. There was a significant difference in the mean SUV’s between the group with transformation and that with indolent lymphoma (7.6 ± 4.6 vs. 4.5 ±2.5). More importantly, the mean values for SUV in the lesions with the highest FDG uptake were significantly different between the two groups (13.8 ±5.3 vs 5.8±2.9). Among the patients who had a biopsy taken from the lesions with the highest SUV’s the range was 8 to 27 and the mean value was 14.9±8.0. Conclusions: In patients with indolent lymphoma, areas of significant increase in FDG (particularly SUV’s >12) should be considered targets for biopsy. Differences in SUV’s Between Transformed and Indolent Lesions Patient Number Mean SUV Mean SUV in Hottest Lesions SUV Range in Hottest Lesions SUV: standardized uptake values Patients with Transformation 12 7.6+/−4.6 13.8+/−5.3 8–27 Patients with Indolent Lymphoma 48 4.5+/−2.5 5.8+/−2.9 2–12

Smartphone Application Helps Improve Adherence to Oral Anticoagulants in Patients with Atrial Fibrillation (Preprint)

2021 ◽  
Author(s):  
Keitaro Senoo ◽  
Tomonori Miki ◽  
Takashi Ohkura ◽  
Hibiki Iwakoshi ◽  
Tetsuro Nishimura ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Medication Adherence ◽  
Oral Anticoagulants ◽  
Anticoagulation Therapy ◽  
Low Grade ◽  
Grade Group ◽  
Time Points ◽  
The Mean ◽  
High Level

BACKGROUND Atrial fibrillation (AF) is a significant risk factor for stroke, especially in aging societies. Anticoagulation therapy is used to prevent stroke and, the efficacy and safety profiles of novel oral anticoagulants (NOACs) are comparable with those of vitamin-K antagonists (VKAs). Although NOACs do not require regular monitoring of anticoagulatory effects, there are concerns that they tend to be less long-lasting and have poorer adherence among patients than VKAs. A new application (the “Smart AF app”) was developed as a tool to improve adherence to oral anticoagulant medication in elderly individuals with AF. OBJECTIVE The aim of the present study was to evaluate the utility of the Smart AF app in individuals with AF. METHODS Patients with AF were enrolled at Kyoto Prefectural University of Medicine hospitals between May 2019 and September 2020. Follow-up was planned at 1, 3, and 6 months after enrollment, and questionnaire reminders were automatically sent to patient applications at designated follow-up time points. A questionnaire-based survey of medication adherence was performed electronically using the self-reported 8-item Morisky Medication Adherence Scale (MMAS-8) as the survey tool. RESULTS A total of 136 patients with AF were enrolled in this study. During the follow-up period, 111 patients underwent follow-up at 1 month, 109 at 3 months, and 96 at 6 months. The mean age of the enrolled patients was 64.3 years, and males accounted for 79.4% of the study population. The mean CHADS2 score was 1.2, with hypertension being the most common comorbidity. At the time of enrollment, 126 and 10 patients were taking oral NOACs and oral warfarin, respectively. At baseline, mean adherence measured according to the MMAS-8 was 6.14 (SD 1.52), and 6.87 (SD 1.30) at 1 month, 6.69 (SD 1.53) at 3 months, and 6.98 (SD 1.34) at 6 months, demonstrating a significant increase at all time points compared with enrollment (all P<.01). The overall improvement in medication adherence with the intervention was attributed to an improvement of 77.8% in the high-grade group to a high level and 45.3% in the medium-grade group to a high level, and 72% in the low-grade group to a medium or high level. CONCLUSIONS The Smart AF app improved medication adherence, even among elderly patients in whom AF is prevalent. In medication administration, an approach that emphasizes education using mobile health technology, simple reminder function, and patient engagement, may be helpful.

Multicenter Phase II Study of Iodine-131 Tositumomab for Chemotherapy-Relapsed/Refractory Low-Grade and Transformed Low-Grade B-Cell Non-Hodgkin’s Lymphomas

2000 ◽  
Vol 18 (6) ◽  
pp. 1316-1323 ◽  
Author(s):  
Julie M. Vose ◽  
Richard L. Wahl ◽  
Mansoor Saleh ◽  
Ama Z. Rohatiner ◽  
Susan J. Knox ◽  
...  
Keyword(s):  
Phase Ii ◽  
Median Duration ◽  
Therapeutic Dose ◽  
Response Rate ◽  
Phase Ii Study ◽  
Low Grade ◽  
Multicenter Phase ◽  
Iodine 131 ◽  
Total Body ◽  
Hodgkin's Lymphomas

PURPOSE: This multicenter phase II study evaluated the efficacy, dosimetry methodology, and safety of iodine-131 tositumomab in patients with chemotherapy-relapsed/refractory low-grade or transformed low-grade non-Hodgkin’s lymphoma (NHL). PATIENTS AND METHODS: Patients received a dosimetric dose that consisted of 450 mg of anti-B1 antibody followed by 35 mg (5 mCi) of iodine-131 tositumomab. Serial total-body gamma counts were then obtained to calculate the patient-specific millicurie activity required to deliver the therapeutic dose. A therapeutic dose of 75 cGy total-body dose (attenuated to 65 cGy in patients with platelet counts of 101,000 to 149,000 cells/mm3) was given 7 to 14 days after the dosimetric dose. RESULTS: Forty-five of 47 patients were treated with a single dosimetric and therapeutic dose. Twenty-seven patients (57%) had a response. The response rate was similar in patients with low-grade (57%) or transformed low-grade (60%) NHL. The median duration of response was 9.9 months. Fifteen patients (32%) achieved a complete response (CR; 10 CRs and five clinical CRs), including five patients (50%) with transformed low-grade NHL. The median duration of CR was 19.9 months, and six patients have an ongoing CR. Treatment was well tolerated, with the principal toxicity being hematologic. The most common nonhematologic toxicities that were considered to be possibly related to the treatment included mild to moderate fatigue (32%), nausea (30%), fever (26%), vomiting (15%), infection (13%), pruritus (13%), and rash (13%). Additionally, one patient developed human-antimouse antibodies. CONCLUSION: Iodine-131 tositumomab produced a high overall response rate, and approximately one third of patients had a CR despite having chemotherapy-relapsed or refractory low-grade or transformed low-grade NHL.

Quantitative Radioisotope Measurement of Duodenogastric Reflux in Patients with Ulcer or Gastrectomized for Ulcer

1985 ◽  
Vol 24 (03) ◽  
pp. 107-110
Author(s):  
M. Pääkkönen ◽  
S. Aukee ◽  
K. Korhonen ◽  
A. Pääkkönen ◽  
E. Länsimies ◽  
...  
Keyword(s):  
Gamma Camera ◽  
Background Activity ◽  
Bile Reflux ◽  
Duodenogastric Reflux ◽  
Upper Limit ◽  
Visual Evidence ◽  
Biochemical Measurement

SummaryIn this work the duodenogastric reflux was quantified as the amount of radioactivity entering the stomach after an i.v. administration of 99mmTc-HIDA in ulcer patients and in patients who had undergone BI gastrectomy. The results were compared with visual evidence of gastric activity in the gamma camera images and biochemical determination of gastric bile reflux. The method is useful in quantifying the reflux if the activity is above the background activity. It allows the determination of an upper limit for the reflux when the reflux is evident visually. Only two or three images are needed for the quantitation. No correlation was found between biochemical measurement of fasting bile reflux in the stomach and radioisotopic quantification.

On the Determination of the Resolution Index of a Gamma Camera

1973 ◽  
Vol 12 (04) ◽  
pp. 360-366
Author(s):  
Barbara Gwiazdowska ◽  
H. Mackiewicz ◽  
J. Tolwinski
Keyword(s):  
Gamma Camera

L’étude tâche d’interpréter les différences des indices de résolution de gamma caméra obtenues expérimentalement et calculées. Les erreurs de mesurage et les conditions de validité des formules utilisées dans les calcules sont discutées. On a pu obtenir un agréement des deux méthodes et une confirmation théorique. On suggert de déterminer quelque condition de mesurage ou de remplacer les méthodes de mesurage par de calcul.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Determination of Plasminogen in Clots and Thrombi

1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson
Keyword(s):  
Mean Value ◽  
Main Mechanism ◽  
Clot Lysis ◽  
Post Mortem ◽  
Digestion Time ◽  
Normal Volunteers ◽  
Casein Solution ◽  
The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

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