ONCOLOGY IMAGING Flashcards
Q: What are the two main forms of imaging?
Functional imaging (e.g., nuclear medicine).
Anatomical imaging (e.g., X-ray, CT, MRI, and ultrasound).
What are the greatest advantages of functional imaging?
Ability to detect physiological changes before structural changes.
Ability to image the whole body in a short time with less radiation.
Q: Provide an example of a tumor and its receptor targeted by a radiopharmaceutical.
Differentiated thyroid cancer → Sodium iodine symporter (radioactive iodine).
Neuroendocrine tumors → Somatostatin receptors (radiolabeled octreotide).
Neural crest tumors → Norepinephrine transporters (MIBG imaging).
Prostate cancer → Prostate-specific membrane antigen (PSMA ligand imaging)
Q: Which radiotracer has the greatest utility in oncology imaging?
A: 18F FDG, as most cancers have high glucose transporter expression and hexokinase activity.
Name three cancers that do not typically have high glucose transporter expression or hexokinase activity.
Well-differentiated thyroid cancers.
Well-differentiated neuroendocrine tumors.
Prostate cancer.
SPECT Tracers:
I-123/131: Imaging differentiated thyroid cancers.
99mTc Octreotide: Imaging differentiated neuroendocrine tumors.
I-123/131 MIBG: Imaging neural crest tumors (e.g., pheochromocytoma, paraganglioma, neuroblastoma, medullary thyroid cancer).
99mTc MDP: Imaging osteoblastic metastases.
Others: 99mTc Sestamibi, Thallium-201, Gallium-67 citrate.
PET Tracers:
I-124: Imaging differentiated thyroid cancers.
Ga-68 DOTA peptides: Imaging differentiated neuroendocrine and neural crest tumors.
Ga-68/F-18 PSMA: Imaging prostate cancer.
18F FDG: Imaging most malignancies.
What are the main indications for oncology imaging in nuclear medicine?
Diagnosis of cancer of unknown primary.
Staging.
Restaging.
Early treatment response assessment.
Radiotherapy planning.
Surveillance and confirmation of recurrent disease.
How does F-18 FDG imaging influence breast cancer management?
A: It can detect lesions not seen on CT, potentially changing management from mastectomy to chemotherapy.
: What is indicated if a tumor appears negative on an I-123 scan but positive on F-18 FDG imaging?
:
A: The tumor has become poorly differentiated and aggressive, with high glucose metabolism.
What imaging tracer is used for nodal metastatic prostate cancer?
A: Ga-68 PSMA.
How does Ga-68 PSMA imaging aid prostate cancer diagnosis?
n accurate site for biopsy.
: Which tracer is used for imaging neuroendocrine tumors of the lung?
A: Ga-68 DOTA peptides.
:
A: Ga-68 DOTA peptides.
Which tracer is used to detect widespread osteoblastic metastases?
A: 99mTc MDP.
Q: True or False: Anatomical changes occur before functional changes in cancer.
A: False.
