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Three-dimensional imaging techniques are changing the scope and precision of planning radiotherapy for cervical cancer. Researchers from Jiaotong University in China who compared planning using 3D magnetic resonance imaging and conventional 2D point A–based intracavitary brachytherapy (BT), say 3D imaging exhibits definite advantages “in a complex way.”
Conventional 2D planning (using a fixed reference point) can overestimate tumor dosages and underestimate the dosages for other organs at risk (OARs), such as rectum and bladder, the researchers say. By contrast in this study, they found that, in general, 3D MRI-based planning helped create accurate estimates for increased dose coverage in big tumors, eccentric tumors, and tumors invading adjacent tissues.
Related: Simultaneous Integrated Boost in Lieu of Vaginal Brachytherapy Boost in Endometrial Cancer
In the study, 79 patients with cervical cancer were treated first with CT-based external beam radiation therapy, then with high-dose rate BT (all patients underwent both 2D and 3D planning for HDR-BT). The researchers compared dose-volume histogram (DVH) parameters for gross tumor volume, high-risk clinical target volume, intermediate-risk clinical target volume, and OARs. Cervical cancer was confirmed by histologic examination on biopsy. Twenty patients had big tumors, and 59 had small tumors.
The researchers say their findings indicate that 3D MRI image-guided BT planning generally show advantages in the treatment of cervical cancer with the exception of cervical cancer that feature small tumors.
For small tumors, DVH parameters did not differ significantly between 2D and 3D BT planning. In big tumors, however, almost all DVH parameters were significantly higher in 3D planning compared with 2D planning. Doses to OARs were also higher.
Related: Early Cancer Detection Helps Underserved Women
The researchers found a “diverse” response of small vs big tumors. In the eccentric cervical tumors, 3D BT planning led to more required dosage and reduced doses to the OARs compared with 2D BT planning. In cervical tumors invading adjacent tissues, 3D planning generally increased the tumor dose coverage but diversely affected the doses to OARs compared with 2D planning.
Only in big tumors, the researchers conclude, does 3D BT planning show obvious advantage.
Source:
Ren J, Yuan W, Wang R, et al. PLoS One. 2016;11(9):e0161932.
doi: 10.1371/journal.pone.0161932.
Three-dimensional imaging techniques are changing the scope and precision of planning radiotherapy for cervical cancer. Researchers from Jiaotong University in China who compared planning using 3D magnetic resonance imaging and conventional 2D point A–based intracavitary brachytherapy (BT), say 3D imaging exhibits definite advantages “in a complex way.”
Conventional 2D planning (using a fixed reference point) can overestimate tumor dosages and underestimate the dosages for other organs at risk (OARs), such as rectum and bladder, the researchers say. By contrast in this study, they found that, in general, 3D MRI-based planning helped create accurate estimates for increased dose coverage in big tumors, eccentric tumors, and tumors invading adjacent tissues.
Related: Simultaneous Integrated Boost in Lieu of Vaginal Brachytherapy Boost in Endometrial Cancer
In the study, 79 patients with cervical cancer were treated first with CT-based external beam radiation therapy, then with high-dose rate BT (all patients underwent both 2D and 3D planning for HDR-BT). The researchers compared dose-volume histogram (DVH) parameters for gross tumor volume, high-risk clinical target volume, intermediate-risk clinical target volume, and OARs. Cervical cancer was confirmed by histologic examination on biopsy. Twenty patients had big tumors, and 59 had small tumors.
The researchers say their findings indicate that 3D MRI image-guided BT planning generally show advantages in the treatment of cervical cancer with the exception of cervical cancer that feature small tumors.
For small tumors, DVH parameters did not differ significantly between 2D and 3D BT planning. In big tumors, however, almost all DVH parameters were significantly higher in 3D planning compared with 2D planning. Doses to OARs were also higher.
Related: Early Cancer Detection Helps Underserved Women
The researchers found a “diverse” response of small vs big tumors. In the eccentric cervical tumors, 3D BT planning led to more required dosage and reduced doses to the OARs compared with 2D BT planning. In cervical tumors invading adjacent tissues, 3D planning generally increased the tumor dose coverage but diversely affected the doses to OARs compared with 2D planning.
Only in big tumors, the researchers conclude, does 3D BT planning show obvious advantage.
Source:
Ren J, Yuan W, Wang R, et al. PLoS One. 2016;11(9):e0161932.
doi: 10.1371/journal.pone.0161932.
Three-dimensional imaging techniques are changing the scope and precision of planning radiotherapy for cervical cancer. Researchers from Jiaotong University in China who compared planning using 3D magnetic resonance imaging and conventional 2D point A–based intracavitary brachytherapy (BT), say 3D imaging exhibits definite advantages “in a complex way.”
Conventional 2D planning (using a fixed reference point) can overestimate tumor dosages and underestimate the dosages for other organs at risk (OARs), such as rectum and bladder, the researchers say. By contrast in this study, they found that, in general, 3D MRI-based planning helped create accurate estimates for increased dose coverage in big tumors, eccentric tumors, and tumors invading adjacent tissues.
Related: Simultaneous Integrated Boost in Lieu of Vaginal Brachytherapy Boost in Endometrial Cancer
In the study, 79 patients with cervical cancer were treated first with CT-based external beam radiation therapy, then with high-dose rate BT (all patients underwent both 2D and 3D planning for HDR-BT). The researchers compared dose-volume histogram (DVH) parameters for gross tumor volume, high-risk clinical target volume, intermediate-risk clinical target volume, and OARs. Cervical cancer was confirmed by histologic examination on biopsy. Twenty patients had big tumors, and 59 had small tumors.
The researchers say their findings indicate that 3D MRI image-guided BT planning generally show advantages in the treatment of cervical cancer with the exception of cervical cancer that feature small tumors.
For small tumors, DVH parameters did not differ significantly between 2D and 3D BT planning. In big tumors, however, almost all DVH parameters were significantly higher in 3D planning compared with 2D planning. Doses to OARs were also higher.
Related: Early Cancer Detection Helps Underserved Women
The researchers found a “diverse” response of small vs big tumors. In the eccentric cervical tumors, 3D BT planning led to more required dosage and reduced doses to the OARs compared with 2D BT planning. In cervical tumors invading adjacent tissues, 3D planning generally increased the tumor dose coverage but diversely affected the doses to OARs compared with 2D planning.
Only in big tumors, the researchers conclude, does 3D BT planning show obvious advantage.
Source:
Ren J, Yuan W, Wang R, et al. PLoS One. 2016;11(9):e0161932.
doi: 10.1371/journal.pone.0161932.