Limits...
The using of megavoltage computed tomography in image-guided brachytherapy for cervical cancer: a case report.

Tharavichitkul E, Janla-Or S, Wanwilairat S, Chakrabandhu S, Klunklin P, Onchan W, Supawongwattana B, Galalae RM, Chitapanarux I - Radiat Oncol J (2015)

Bottom Line: We present a case of cervical cancer treated by concurrent chemoradiation.In radiation therapy part, the combination of the whole pelvic helical tomotherapy plus image-guided brachytherapy with megavoltage computed tomography of helical tomotherapy was performed.We propose this therapeutic approach could be considered in a curative setting in some problematic situation as our institution.

View Article: PubMed Central - PubMed

Affiliation: Division of Therapeutic Radiology and Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.

ABSTRACT
We present a case of cervical cancer treated by concurrent chemoradiation. In radiation therapy part, the combination of the whole pelvic helical tomotherapy plus image-guided brachytherapy with megavoltage computed tomography of helical tomotherapy was performed. We propose this therapeutic approach could be considered in a curative setting in some problematic situation as our institution.

No MeSH data available.


Related in: MedlinePlus

Megavoltage computed tomography image in (A) transverse and (B) sagittal views showed the contours of HR-CTV (red), IR-CTV (blue), bladder (light blue), and sigmoid colon (green). HR-CTV, high-risk clinical target volume; IR-CTV, intermediate-risk clinical target volume.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493428&req=5

Figure 4: Megavoltage computed tomography image in (A) transverse and (B) sagittal views showed the contours of HR-CTV (red), IR-CTV (blue), bladder (light blue), and sigmoid colon (green). HR-CTV, high-risk clinical target volume; IR-CTV, intermediate-risk clinical target volume.

Mentions: For WPHT, we can use outsource CT from our faculty branch, but it is impossible to transfer patient with applicator to that place. To solve this problem, we thought about using of the MVCT of HT situated close to our brachytherapy suite. The first brachytherapy was performed after the fourth week of EBRT. To reduce the artifact, Rotterdam Titanium applicator (Nucletron-Elekta, Stockholm, Sweden) was used (Fig. 3). A Foley catheter was placed in the bladder and filled with contrast media and normal saline solution to identify the bladder volume for imaging planning. The vagina was packed with gauze to increase the distance between the radiation source, and the rectum and bladder. The WPHT was interrupted for each day of high-dose rate (HDR) brachytherapy insertion. After application, the patient was transferred to imaging devices, and the pelvic region from the iliac crest to the ischial tuberosity was scanned without intravenous contrast to obtain appropriate images with the patients in a supine treatment position with their legs relaxed on the table. The MVCT was performed with 4-mm slice thickness without an interslice gap. After the imaging was performed the position of the applicators was checked before being transferred to the planning system (Nucletron Oncentra). Patients were then transferred to the brachytherapy treatment room and adjusted to the same position as in the imaging devices. MVCT image was used and GEC-ESTRO definitions were applied to identify target volumes, e.g., high-risk clinical target volume (HR-CTV), and OARs [345]. Dose-volume histograms were calculated to consider the adequate dose to HR-CTV and limitations of OARs. The minimum dose covering 90% of volumes (D90) of the HR-CTV and representing the maximum doses calculated at the most irradiated 2 cc volumes (D2cc) of OARs were recorded according to GEC-ESTRO recommendations. The prescribed dose to the D90 of HR-CTV was at least 7 Gy × 4 fractions. Optimizations were performed to improve the dose distribution to HR-CTV, bladder, rectum, and sigmoid colon (Fig. 4). The D90 of HR-CTV and D2cc of OARs were recorded to evaluate the cumulative dose in EQD2 concepts [6].


The using of megavoltage computed tomography in image-guided brachytherapy for cervical cancer: a case report.

Tharavichitkul E, Janla-Or S, Wanwilairat S, Chakrabandhu S, Klunklin P, Onchan W, Supawongwattana B, Galalae RM, Chitapanarux I - Radiat Oncol J (2015)

Megavoltage computed tomography image in (A) transverse and (B) sagittal views showed the contours of HR-CTV (red), IR-CTV (blue), bladder (light blue), and sigmoid colon (green). HR-CTV, high-risk clinical target volume; IR-CTV, intermediate-risk clinical target volume.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493428&req=5

Figure 4: Megavoltage computed tomography image in (A) transverse and (B) sagittal views showed the contours of HR-CTV (red), IR-CTV (blue), bladder (light blue), and sigmoid colon (green). HR-CTV, high-risk clinical target volume; IR-CTV, intermediate-risk clinical target volume.
Mentions: For WPHT, we can use outsource CT from our faculty branch, but it is impossible to transfer patient with applicator to that place. To solve this problem, we thought about using of the MVCT of HT situated close to our brachytherapy suite. The first brachytherapy was performed after the fourth week of EBRT. To reduce the artifact, Rotterdam Titanium applicator (Nucletron-Elekta, Stockholm, Sweden) was used (Fig. 3). A Foley catheter was placed in the bladder and filled with contrast media and normal saline solution to identify the bladder volume for imaging planning. The vagina was packed with gauze to increase the distance between the radiation source, and the rectum and bladder. The WPHT was interrupted for each day of high-dose rate (HDR) brachytherapy insertion. After application, the patient was transferred to imaging devices, and the pelvic region from the iliac crest to the ischial tuberosity was scanned without intravenous contrast to obtain appropriate images with the patients in a supine treatment position with their legs relaxed on the table. The MVCT was performed with 4-mm slice thickness without an interslice gap. After the imaging was performed the position of the applicators was checked before being transferred to the planning system (Nucletron Oncentra). Patients were then transferred to the brachytherapy treatment room and adjusted to the same position as in the imaging devices. MVCT image was used and GEC-ESTRO definitions were applied to identify target volumes, e.g., high-risk clinical target volume (HR-CTV), and OARs [345]. Dose-volume histograms were calculated to consider the adequate dose to HR-CTV and limitations of OARs. The minimum dose covering 90% of volumes (D90) of the HR-CTV and representing the maximum doses calculated at the most irradiated 2 cc volumes (D2cc) of OARs were recorded according to GEC-ESTRO recommendations. The prescribed dose to the D90 of HR-CTV was at least 7 Gy × 4 fractions. Optimizations were performed to improve the dose distribution to HR-CTV, bladder, rectum, and sigmoid colon (Fig. 4). The D90 of HR-CTV and D2cc of OARs were recorded to evaluate the cumulative dose in EQD2 concepts [6].

Bottom Line: We present a case of cervical cancer treated by concurrent chemoradiation.In radiation therapy part, the combination of the whole pelvic helical tomotherapy plus image-guided brachytherapy with megavoltage computed tomography of helical tomotherapy was performed.We propose this therapeutic approach could be considered in a curative setting in some problematic situation as our institution.

View Article: PubMed Central - PubMed

Affiliation: Division of Therapeutic Radiology and Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.

ABSTRACT
We present a case of cervical cancer treated by concurrent chemoradiation. In radiation therapy part, the combination of the whole pelvic helical tomotherapy plus image-guided brachytherapy with megavoltage computed tomography of helical tomotherapy was performed. We propose this therapeutic approach could be considered in a curative setting in some problematic situation as our institution.

No MeSH data available.


Related in: MedlinePlus