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Determination of Radiation Absorbed Dose to Primary Liver Tumors and Normal Liver Tissue Using Post-Radioembolization (90)Y PET.

Srinivas SM, Natarajan N, Kuroiwa J, Gallagher S, Nasr E, Shah SN, DiFilippo FP, Obuchowski N, Bazerbashi B, Yu N, McLennan G - Front Oncol (2014)

Bottom Line: Normal liver tissue received a mean dose of 67 Gy (mode 60-70 Gy; range 10-120 Gy).There was a statistically significant association between absorbed dose to normal liver and the presence of two or more severe complications (p = 0.036).Collateral dose to normal liver is non-trivial and can have clinical implications.

View Article: PubMed Central - PubMed

Affiliation: Department of Nuclear Medicine, Cleveland Clinic , Cleveland, OH , USA.

ABSTRACT

Background: Radioembolization with Yttrium-90 ((90) Y) microspheres is becoming a more widely used transcatheter treatment for unresectable hepatocellular carcinoma (HCC). Using post-treatment (90) Y positron emission tomography/computerized tomography (PET/CT) scans, the distribution of microspheres within the liver can be determined and quantitatively assessed. We studied the radiation dose of (90) Y delivered to liver and treated tumors.

Methods: This retrospective study of 56 patients with HCC, including analysis of 98 liver tumors, measured and correlated the dose of radiation delivered to liver tumors and normal liver tissue using glass microspheres (TheraSpheres(®)) to the frequency of complications with modified response evaluation criteria in solid tumors (mRECIST). (90) Y PET/CT and triphasic liver CT scans were used to contour treated tumor and normal liver regions and determine their respective activity concentrations. An absorbed dose factor was used to convert the measured activity concentration (Bq/mL) to an absorbed dose (Gy).

Results: The 98 studied tumors received a mean dose of 169 Gy (mode 90-120 Gy; range 0-570 Gy). Tumor response by mRECIST criteria was performed for 48 tumors that had follow-up scans. There were 21 responders (mean dose 215 Gy) and 27 non-responders (mean dose 167 Gy). The association between mean tumor absorbed dose and response suggests a trend but did not reach statistical significance (p = 0.099). Normal liver tissue received a mean dose of 67 Gy (mode 60-70 Gy; range 10-120 Gy). There was a statistically significant association between absorbed dose to normal liver and the presence of two or more severe complications (p = 0.036).

Conclusion: Our cohort of patients showed a possible dose-response trend for the tumors. Collateral dose to normal liver is non-trivial and can have clinical implications. These methods help us understand whether patient adverse events, treatment success, or treatment failure can be attributed to the dose that the tumor or normal liver received.

No MeSH data available.


Related in: MedlinePlus

This figure shows a scatter plot representation of tumor dose (Gy) in relation to tumor volume (mL).
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Figure 5: This figure shows a scatter plot representation of tumor dose (Gy) in relation to tumor volume (mL).

Mentions: The analysis on our cohort suggests that the mean dose received among the 98 studied tumors was 169 Gy with a mode of 90–120 Gy and a treatment dose range of 0–570 Gy. The overall distribution of doses delivered to tumor is displayed in Figure 4. Additionally, Figure 5 indicates the relationship between tumor dose and tumor volume. This scatter plot shows the inherent difficulty in achieving a substantial Gy in a tumor of large volume. If one were to consider >100 Gy to be a treatment goal (6), then clearly the majority of the tumors in which this was achieved were smaller than 100 mL in volume.


Determination of Radiation Absorbed Dose to Primary Liver Tumors and Normal Liver Tissue Using Post-Radioembolization (90)Y PET.

Srinivas SM, Natarajan N, Kuroiwa J, Gallagher S, Nasr E, Shah SN, DiFilippo FP, Obuchowski N, Bazerbashi B, Yu N, McLennan G - Front Oncol (2014)

This figure shows a scatter plot representation of tumor dose (Gy) in relation to tumor volume (mL).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4195277&req=5

Figure 5: This figure shows a scatter plot representation of tumor dose (Gy) in relation to tumor volume (mL).
Mentions: The analysis on our cohort suggests that the mean dose received among the 98 studied tumors was 169 Gy with a mode of 90–120 Gy and a treatment dose range of 0–570 Gy. The overall distribution of doses delivered to tumor is displayed in Figure 4. Additionally, Figure 5 indicates the relationship between tumor dose and tumor volume. This scatter plot shows the inherent difficulty in achieving a substantial Gy in a tumor of large volume. If one were to consider >100 Gy to be a treatment goal (6), then clearly the majority of the tumors in which this was achieved were smaller than 100 mL in volume.

Bottom Line: Normal liver tissue received a mean dose of 67 Gy (mode 60-70 Gy; range 10-120 Gy).There was a statistically significant association between absorbed dose to normal liver and the presence of two or more severe complications (p = 0.036).Collateral dose to normal liver is non-trivial and can have clinical implications.

View Article: PubMed Central - PubMed

Affiliation: Department of Nuclear Medicine, Cleveland Clinic , Cleveland, OH , USA.

ABSTRACT

Background: Radioembolization with Yttrium-90 ((90) Y) microspheres is becoming a more widely used transcatheter treatment for unresectable hepatocellular carcinoma (HCC). Using post-treatment (90) Y positron emission tomography/computerized tomography (PET/CT) scans, the distribution of microspheres within the liver can be determined and quantitatively assessed. We studied the radiation dose of (90) Y delivered to liver and treated tumors.

Methods: This retrospective study of 56 patients with HCC, including analysis of 98 liver tumors, measured and correlated the dose of radiation delivered to liver tumors and normal liver tissue using glass microspheres (TheraSpheres(®)) to the frequency of complications with modified response evaluation criteria in solid tumors (mRECIST). (90) Y PET/CT and triphasic liver CT scans were used to contour treated tumor and normal liver regions and determine their respective activity concentrations. An absorbed dose factor was used to convert the measured activity concentration (Bq/mL) to an absorbed dose (Gy).

Results: The 98 studied tumors received a mean dose of 169 Gy (mode 90-120 Gy; range 0-570 Gy). Tumor response by mRECIST criteria was performed for 48 tumors that had follow-up scans. There were 21 responders (mean dose 215 Gy) and 27 non-responders (mean dose 167 Gy). The association between mean tumor absorbed dose and response suggests a trend but did not reach statistical significance (p = 0.099). Normal liver tissue received a mean dose of 67 Gy (mode 60-70 Gy; range 10-120 Gy). There was a statistically significant association between absorbed dose to normal liver and the presence of two or more severe complications (p = 0.036).

Conclusion: Our cohort of patients showed a possible dose-response trend for the tumors. Collateral dose to normal liver is non-trivial and can have clinical implications. These methods help us understand whether patient adverse events, treatment success, or treatment failure can be attributed to the dose that the tumor or normal liver received.

No MeSH data available.


Related in: MedlinePlus