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Use of radioactive substances in diagnosis and treatment of neuroendocrine tumors.

Kjaer A, Knigge U - Scand. J. Gastroenterol. (2015)

Bottom Line: They perform better than SPECT tracers and should be preferred.However, with FDG-PET and somatostatin receptor PET at hand we see limited necessity of other tracers.Grade 3-4 kidney or bone marrow toxicity is seen in 1.5% and 9.5%, respectively, but are completely or partly reversible in most patients. (177)Lu-DOTATATE seems to have less toxicity than (90)Y-DOTATOC.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging , Copenhagen , Denmark.

ABSTRACT
Radionuclides are needed both for nuclear medicine imaging as well as for peptide-receptor radionuclide therapy (PRRT) of neuroendocrine tumors (NET). Imaging is important in the initial diagnostic work-up and for staging NETs. In therapy planning, somatostatin receptor imaging (SRI) is used when treatment is targeted at the somatostatin receptors as with the use of somatostatin analogues or PRRT. SRI with gamma camera technique using the tracer (111)In-DTPA-octreotide has for many years been the backbone of nuclear imaging of NETs. However, increasingly PET tracers for SRI are now used. (68)Ga-DOTATATE, (68)Ga-DOTATOC and (68)Ga-DOTANOC are the three most often used PET tracers. They perform better than SPECT tracers and should be preferred. FDG-PET is well suited for visualization of most of the somatostatin receptor-negative tumors prognostic in NET patients. Also (11)C-5-HTP, (18)F-DOPA and (123)I-MIBG may be used in NET. However, with FDG-PET and somatostatin receptor PET at hand we see limited necessity of other tracers. PRRT is an important tool in the treatment of advanced NETs causing complete or partial response in 20% and minor response or tumor stabilization in 60% with response duration of up to 3 years. Grade 3-4 kidney or bone marrow toxicity is seen in 1.5% and 9.5%, respectively, but are completely or partly reversible in most patients. (177)Lu-DOTATATE seems to have less toxicity than (90)Y-DOTATOC. However, until now only retrospective, non-randomized studies have been performed and the role of PRRT in treatment of NETs remains to be established.

No MeSH data available.


Related in: MedlinePlus

CT scan of a patient with a non-functioning pancreatic NET before and 6 months after treatment with four cycles of 177Lu-DOTATATE. The size of the liver is reduced and almost all metastases have disappeared.
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Figure 0002: CT scan of a patient with a non-functioning pancreatic NET before and 6 months after treatment with four cycles of 177Lu-DOTATATE. The size of the liver is reduced and almost all metastases have disappeared.

Mentions: All studies published to date are retrospective with no randomization. Furthermore, patients selected for PRRT varies from study to study concerning performance status, tumor type, tumor load as well as disease state at time of PRRT initiation. Following treatment with 90Y or 177Lu generally complete response is seen in <5%, partial response in 10–35%, minor response + stable disease in 50–80% and progressive disease in 10–20% [48, 49, 50, 51] (Figure 2). Thus, rather large differences exists between the studies performed regarding tumor response, which may be caused by the reasons mentioned above as well as dose and/or treatment cycles used. In general, a tumor response may be seen up to 6–12 months after PRRT. Pancreatic NET seems to respond better to PRRT than small intestinal NET [51]. Best tumor response is found in patients with high uptake at SRI, minor liver tumor load and high Karnofsky performance score [48, 50].


Use of radioactive substances in diagnosis and treatment of neuroendocrine tumors.

Kjaer A, Knigge U - Scand. J. Gastroenterol. (2015)

CT scan of a patient with a non-functioning pancreatic NET before and 6 months after treatment with four cycles of 177Lu-DOTATATE. The size of the liver is reduced and almost all metastases have disappeared.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4487540&req=5

Figure 0002: CT scan of a patient with a non-functioning pancreatic NET before and 6 months after treatment with four cycles of 177Lu-DOTATATE. The size of the liver is reduced and almost all metastases have disappeared.
Mentions: All studies published to date are retrospective with no randomization. Furthermore, patients selected for PRRT varies from study to study concerning performance status, tumor type, tumor load as well as disease state at time of PRRT initiation. Following treatment with 90Y or 177Lu generally complete response is seen in <5%, partial response in 10–35%, minor response + stable disease in 50–80% and progressive disease in 10–20% [48, 49, 50, 51] (Figure 2). Thus, rather large differences exists between the studies performed regarding tumor response, which may be caused by the reasons mentioned above as well as dose and/or treatment cycles used. In general, a tumor response may be seen up to 6–12 months after PRRT. Pancreatic NET seems to respond better to PRRT than small intestinal NET [51]. Best tumor response is found in patients with high uptake at SRI, minor liver tumor load and high Karnofsky performance score [48, 50].

Bottom Line: They perform better than SPECT tracers and should be preferred.However, with FDG-PET and somatostatin receptor PET at hand we see limited necessity of other tracers.Grade 3-4 kidney or bone marrow toxicity is seen in 1.5% and 9.5%, respectively, but are completely or partly reversible in most patients. (177)Lu-DOTATATE seems to have less toxicity than (90)Y-DOTATOC.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging , Copenhagen , Denmark.

ABSTRACT
Radionuclides are needed both for nuclear medicine imaging as well as for peptide-receptor radionuclide therapy (PRRT) of neuroendocrine tumors (NET). Imaging is important in the initial diagnostic work-up and for staging NETs. In therapy planning, somatostatin receptor imaging (SRI) is used when treatment is targeted at the somatostatin receptors as with the use of somatostatin analogues or PRRT. SRI with gamma camera technique using the tracer (111)In-DTPA-octreotide has for many years been the backbone of nuclear imaging of NETs. However, increasingly PET tracers for SRI are now used. (68)Ga-DOTATATE, (68)Ga-DOTATOC and (68)Ga-DOTANOC are the three most often used PET tracers. They perform better than SPECT tracers and should be preferred. FDG-PET is well suited for visualization of most of the somatostatin receptor-negative tumors prognostic in NET patients. Also (11)C-5-HTP, (18)F-DOPA and (123)I-MIBG may be used in NET. However, with FDG-PET and somatostatin receptor PET at hand we see limited necessity of other tracers. PRRT is an important tool in the treatment of advanced NETs causing complete or partial response in 20% and minor response or tumor stabilization in 60% with response duration of up to 3 years. Grade 3-4 kidney or bone marrow toxicity is seen in 1.5% and 9.5%, respectively, but are completely or partly reversible in most patients. (177)Lu-DOTATATE seems to have less toxicity than (90)Y-DOTATOC. However, until now only retrospective, non-randomized studies have been performed and the role of PRRT in treatment of NETs remains to be established.

No MeSH data available.


Related in: MedlinePlus