Related Experiment Video
Updated: Jan 23, 2026
10:26
A Multicenter MRI Protocol for the Evaluation and Quantification of Deep Vein Thrombosis
Published on: June 2, 2015
17.9K
Interobserver reproducibility of tumor uptake quantification with 89Zr-immuno-PET: a multicenter analysis
Yvonne W S Jauw1,2, Frederike Bensch3, Adrienne H Brouwers4
1Department of Hematology, Cancer Center Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands. yws.jauw@amsterdamumc.nl.
Summary
Interobserver reproducibility of tumor uptake quantification using 89-zirconium (89Zr)-immuno-PET scans was excellent for SUVmax and SUVpeak with manual segmentation. Semi-automatic methods showed limited robustness due to low tumor contrast.
Area of Science:
- Nuclear Medicine
- Radiopharmaceuticals
- Oncology Imaging
Background:
- 89-zirconium (89Zr)-labeled monoclonal antibodies (mAbs) with PET enable in-vivo tumor uptake quantification.
- Optimizing tumor targeting and therapeutic efficacy is a key goal.
- Low tumor contrast in 89Zr-immuno-PET poses challenges for accurate delineation and can lead to interobserver variation.
Purpose of the Study:
- To assess the interobserver reproducibility of tumor uptake measurements derived from 89Zr-immuno-PET scans.
- To evaluate the reliability of manual tumor delineation for quantitative analysis.
- To compare manual and semi-automatic methods for volume of interest (VOI) delineation.
Main Methods:
- Retrospective analysis of clinical data using 89Zr-rituximab, 89Zr-cetuximab, and 89Zr-trastuzumab.
- Manual delineation of tumor volumes of interest (VOIs) by three independent observers.
- Quantification of tumor uptake using maximum, peak, and mean standardized uptake values (SUVmax, SUVpeak, SUVmean).
- Calculation of interobserver variability using the coefficient of variation (CoV).
- Evaluation of a semi-automatic delineation method based on background-corrected ACpeak.
Main Results:
- A total of 103 VOIs were delineated 3-6 days post-injection.
- Excellent interobserver reproducibility was observed for SUVmax (0% CoV) and SUVpeak (0% CoV).
- SUVmean showed moderate interobserver variability (7% CoV).
- The semi-automatic delineation method achieved a success rate of only 45%, primarily failing due to background inclusion.
Conclusions:
- Standardized manual tumor segmentation on 89Zr-immuno-PET provides excellent interobserver reproducibility for SUVmax and SUVpeak.
- Semi-automatic delineation is not yet robust for quantitative analysis due to challenges with low tumor contrast.
- Manual delineation remains a reliable method for quantitative tumor uptake assessment in 89Zr-immuno-PET studies.
Related Concept Videos
01:21Drugs Affecting Neurotransmitter Release or Uptake
1.6K
Certain drugs can affect how neurotransmitters called catecholamines, are released or taken back up in the adrenergic neuron. They can have different effects on the body's sympathetic transmission. Reserpine, a natural compound found in the Rauwolfia shrub, blocks a transporter called vesicular monoamine transporter (VMAT), which leads to a buildup of catecholamines in the cell and reduces sympathetic transmission. Another drug called guanethidine works in multiple ways, including blocking...
1.6K
01:13Radiological Investigation III: Pulmonary Angiogram and PET Scan
429
Radiological investigations are paramount in the diagnosis and management of various pulmonary diseases. Two essential investigations are the Pulmonary Angiogram and the Positron Emission Tomography (PET) Scan.
Pulmonary Angiogram
A Pulmonary Angiogram is an invasive procedure involving injecting a contrast medium through a catheter threaded into the pulmonary artery or the right side of the heart to visualize the pulmonary vasculature. Computed Tomography (CT) scans have mainly replaced this...
Pulmonary Angiogram
A Pulmonary Angiogram is an invasive procedure involving injecting a contrast medium through a catheter threaded into the pulmonary artery or the right side of the heart to visualize the pulmonary vasculature. Computed Tomography (CT) scans have mainly replaced this...
429
01:27Tumor Immunotherapy
1.8K
Immunotherapy is a treatment that boosts or manipulates the immune system to fight diseases, including cancer. For instance, by stimulating an immune response through vaccinations against viruses that cause cancers, like hepatitis B virus and human papillomavirus, these diseases can be prevented. Nonetheless, some cancer cells can avoid the immune system due to their rapid mutation and division. The immune response to many cancers involves three phases: elimination, equilibrium, and escape.
1.8K
01:14Agonism and Antagonism: Quantification
1.0K
When drugs are administered, they can elicit either an agonist or antagonist effect on the body. Agonism occurs when a drug activates a specific receptor, triggering a biological response. On the other hand, antagonism happens when a drug binds to the same receptors but blocks their activation, thereby preventing a biological response.
To quantify these effects, researchers use a dose-response curve, which provides valuable information about the potency and efficacy of a drug. Potency refers to...
To quantify these effects, researchers use a dose-response curve, which provides valuable information about the potency and efficacy of a drug. Potency refers to...
1.0K
02:07Tumor Progression
7.3K
Tumor progression is a phenomenon where the pre-formed tumor acquires successive mutations to become clinically more aggressive and malignant. In the 1950s, Foulds first described the stepwise progression of cancer cells through successive stages.
Colon cancer is one of the best-documented examples of tumor progression. Early mutation in the APC gene in colon cells causes a small growth on the colon wall called a polyp. With time, this polyp grows into a benign, pre-cancerous tumor. Further...
Colon cancer is one of the best-documented examples of tumor progression. Early mutation in the APC gene in colon cells causes a small growth on the colon wall called a polyp. With time, this polyp grows into a benign, pre-cancerous tumor. Further...
7.3K
02:17The Tumor Microenvironment
7.7K
Every normal cell or tissue is embedded in a complex local environment called stroma, consisting of different cell types, a basal membrane, and blood vessels. As normal cells mutate and develop into cancer cells, their local environment also changes to allow cancer progression. The tumor microenvironment (TME) consists of a complex cellular matrix of stromal cells and the developing tumor. The cross-talk between cancer cells and surrounding stromal cells is critical to disrupt normal tissue...
7.7K