Treatment planning of radiotherapy for skull base involvement of multiple myeloma presenting with visual impairment should be optimized to alleviate symptoms immediately and sufficiently while minimizing toxicities. T...Treatment planning of radiotherapy for skull base involvement of multiple myeloma presenting with visual impairment should be optimized to alleviate symptoms immediately and sufficiently while minimizing toxicities. Two such patients were treated with fractionated stereotactic radiotherapy by using Dynamic Conformal Arcs (DCA) under image guidance based on bony anatomy alignment. DCA planning was optimized after considering the possibility for amendment of visual organ displacement resulting from early tumor shrinkage during treatment through 1) the use of a target volume with modified geometry as a surrogate for leaf adaptation in order to improve target coverage, and 2) manual adjustment of a subset of leaf positions to reduce the dose gradient immediately inside the target boundary facing the visual organs and to eliminate an undesirable dose hotspot. In both cases, anticipated geometric changes in the target volume associated with improvement of visual organ displacement toward the target centroid were observed before the completion of treatment. Favorable visual functional outcomes as well as local tumor control were achieved during 14 months and 4 months follow-up periods. Notably, inexorable visual loss in one patient was fully reversed within one month after radiotherapy. We described the modification techniques for DCA planning in detail.展开更多
Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular ...Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular carcinoma(HCC). Currently, more advanced techniques, including intensity-modulated radiotherapy(IMRT), stereotactic ablative body radiotherapy(SABR), and charged particle therapy, are used for the treatment of HCC. IMRT can escalate the tumor dose while sparing the normal tissue even though the tumor is large or located near critical organs. SABR can deliver a very high radiation dose to small HCCs in a few fractions, leading to high local control rates of 84%-100%. Various advanced imaging modalities are used for radiotherapy planning and delivery to improve the precision of radiotherapy. These advanced techniques enable the delivery of high dose radiotherapy for early to advanced HCCs without increasing the radiation-induced toxicities. However, as there have been no effective tools for the prediction of the response to radiotherapy or recurrences within or outside the radiation field, future studies should focus on selecting the patients who will benefit from radiotherapy.展开更多
文摘Treatment planning of radiotherapy for skull base involvement of multiple myeloma presenting with visual impairment should be optimized to alleviate symptoms immediately and sufficiently while minimizing toxicities. Two such patients were treated with fractionated stereotactic radiotherapy by using Dynamic Conformal Arcs (DCA) under image guidance based on bony anatomy alignment. DCA planning was optimized after considering the possibility for amendment of visual organ displacement resulting from early tumor shrinkage during treatment through 1) the use of a target volume with modified geometry as a surrogate for leaf adaptation in order to improve target coverage, and 2) manual adjustment of a subset of leaf positions to reduce the dose gradient immediately inside the target boundary facing the visual organs and to eliminate an undesirable dose hotspot. In both cases, anticipated geometric changes in the target volume associated with improvement of visual organ displacement toward the target centroid were observed before the completion of treatment. Favorable visual functional outcomes as well as local tumor control were achieved during 14 months and 4 months follow-up periods. Notably, inexorable visual loss in one patient was fully reversed within one month after radiotherapy. We described the modification techniques for DCA planning in detail.
文摘Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular carcinoma(HCC). Currently, more advanced techniques, including intensity-modulated radiotherapy(IMRT), stereotactic ablative body radiotherapy(SABR), and charged particle therapy, are used for the treatment of HCC. IMRT can escalate the tumor dose while sparing the normal tissue even though the tumor is large or located near critical organs. SABR can deliver a very high radiation dose to small HCCs in a few fractions, leading to high local control rates of 84%-100%. Various advanced imaging modalities are used for radiotherapy planning and delivery to improve the precision of radiotherapy. These advanced techniques enable the delivery of high dose radiotherapy for early to advanced HCCs without increasing the radiation-induced toxicities. However, as there have been no effective tools for the prediction of the response to radiotherapy or recurrences within or outside the radiation field, future studies should focus on selecting the patients who will benefit from radiotherapy.
