ENDOMETRİUM KANSERLERİNDE YOĞUNLUK AYARLI RADYOTERAPİ İLE 3 BOYUTLU KONFORMAL RADYOTERAPİNİN DOZİMETRİK OLARAK KARŞILAŞTIRILMASI
Abstract
Endometrium kanserli olgularda 3 boyutlu konformal radyoterapi
(3B KRT) ile yoğunluk ayarlı radyoterapinin (YART) doz volüm
histogramlarının karşılaştırılması ve YART’ın kalite kontrolünün
değerlendirilmesi amaçlanmaktadır. Erken evre endometrium kanserli 15
olgu çal›flmaya dahil edilmifltir. Olgular›n prone pozisyonda bilgisayarları
tomografi görüntüleri alınmıştır, ve tedavi planlama sisteminde
CTV (klinik tümör volümü), PTV (planlanan tedavi volümü) ve kritik
organlar olan ince bağırsak, rektum ve mesane volümleri
belirlenmiştir. Her olgu için 3B KRT ve YART tedavi tekniklerine göre
planlamalar yapılmış ve doz volüm histogramları karşılaştırmıştır.
YART tekniğinin kalite kontrolünde, planlanan ve ölçülen dozları
karşılşmak için absolüt dozimetrede iyon odası ve rölatif dozimetrede
radyografik x ışını doğrulama filmleri kullanılmıştır.
YART’de 3BKRT ile karşılaştırıldığında; rektum, mesane ve ince
bağırsak için 45 Gy alan doz volüm yüzdeli¤inde azalma saptanmıştır
(sırasıyla; %50, %42, %4, p<0.05). PTV 4500 cGy alacak şekilde planlama
yapıldığında, hacmin %95’inin aldığı doz 3B KRT’de 4418 cGy
iken YART modelinde 4500 cGy olup, YART modelinde PTV’nin daha
homojen sarıldığı gösterilmifltir. YART’ın kalite kontrol
değerlendirmesinde hata payları sın›ılar içinde bulunmuş, rölatif
dozimetrede ortalama hata %1.088, ve absolüt dozimetrede gamma
indeksin (g) £1 oldu¤u saptanmıştır. Sonuç olarak endometrium
kanserlerinde YART tedavi tekniğinin, 3B KRT tekniğine göre PTV’de
daha homojen doz dağılımı, kritik organ dozlarında daha fazla düşüş
sağladığı ve tedavinin yüksek doğrulukta uygulanabileceği gösterilmiştir.
Keywords
Endometrium kanseri konformal radyoterapi yoğunluk ayarlı radyoterapi doz volüm histogramı kalite kontrol
References
- 1. Creutzberg CI, van Putten WI, Koper PC ve ark. Surgery and postoperative radiotherapy versus surgery alone for patients with stage I endometrial carcinoma: multicentre randomized trial. PORTEC Study Group. Postoperative Radiation Therapy in Endometrial Carcinoma. Lancet 2000;353:1404-1411.
- 2. Keys HM, Roberts JA, Brunetto VI ve ark. A phase III trial of surgery with or without adjunctive external pelvic radiation therapy in intermediate risk endometrial adenocarcinoma. A Gynecologic Oncology Group study. Gynecol Oncol 2004; 92: 744-751.
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- 5. Roeske J, Lujan A, Rotmensch J, Waggoner SE, Yamada D, Mundt AJ. Intensity-modulated whole pelvic radiation therapy in patients with gynecologic malignancies. Int J Radiat Oncol Biol Phys 2000:8:1613–1621.
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- 7. Bouchard M, Nadeau S, Gingras LC ve ark. Clinical outcome of adjuvant treatment of endometrial cancer using aperture-based intensity-modulated radiotherapy. Int J Radiat Oncol Biol Phys 2008; 71:1343–1350.
- 8. Mundt AJ, Mell LK, Roeske JC. Preliminary analysis of chronic gastrointestinal toxicity in gynecology patients treated with intensity-modulated whole pelvic radiation therapy. Int J Radiat Oncol Biol Phys 2003; 56:1354- 1360.
- 9. Beriwal S, Jain K, Heron E, de Andrade RS, Lin CJ, Kim H. Dosimetric and toxicity comparison between prone and supine position imrt for endometrial cancer. Int J Radiat Oncol Biol Phys 2007; 67: 485–489
- 10. Heron DE, Gerszten K, Selvaraj RN, ve ark Conventional 3D conformal versus intensity-modulated radiotherapy for the adjuvant treatment of gynecologic malignancies: a comparative dosimetric study of dose-volume histograms small star, filled. Gynecol Oncol. 2003;91:39-45.
- 11. Salama J, Mundt J, Roeske J, Mehta N. Preliminary outcome and toxicity report of extended-field, intensitymodulated radiation therapy for gynecologic malignancies Int J Radiat Oncol Biol Phys 2006; 65: 1170–1176.
- 12. Nadeau S, Bouchard M, Germain E ve ark. Postoperative irradiation of gynecologic malignancies:improving treatment delivery using aperture-based intensity-modulated radiotherapy. Int J Radiat Oncol Biol Phys 2007; 68: 601–611.
- 13. E.B. Podgorsak: International atomic energy agency radiation oncology physics: a handbook for teachers and students, 2005.
- 14. Khan FM: The physics of radiation therapy, 3. ed., 2003
Abstract
Our aim is to compare dose-volume histograms of 3D conformal
radiotherapy with intensity modulated radiotherapy (IMRT) and to
test the quality assurance of IMRT in endometrial cancer patients.
Fifteen consecutive patients with early stage endometrial cancer were
included in the study. Computed tomography (CT) scans of each
patients were obtained in prone position and CTV (clinical target volume),
PTV (planning target volume) and organs at risk (bladder, rectum
and small intestine) volumes were delineated on treatment planning
system. Each patient was planned with 3D conformal radiotherapy
(4-field pelvic box) and IMRT and dose-volume histograms of
each plan were compared. Calculated and measured doses of IMRT
plans were compared for the quality assurance purposes of IMRT
using the following 2 methods: 1) ion chamber for absolute dosimetry
2) radiographical X ray film verification for relative dosimetry. IMRT
reduced V45 of rectum, bladder and small intestine by (50%, 42%, 4%
p<0.05, respectively). Both plans were normalized to deliver 4500 cGy
to the PTV and D95 of PTV was 4500 cGy for IMRT and 4418 cGy for
3D CRT and more homogenous dose coverage was achieved with
IMRT. Quality assurance tests of IMRT revealed that margin of error
was within the limits (mean error was 1.088% for relative dosimetry
and gamma index (g) was £1 for absolute dosimetry). In conclusion
IMRT provides better PTV coverage and decreases the doses of critical
organs and the quality assurance results suggest that IMRT could
be performed with high precision.
Keywords
Endometrial cancer conformal radiotherapy intensity modulated radiotherapy dose volume histogram quality assurance.
References
- 1. Creutzberg CI, van Putten WI, Koper PC ve ark. Surgery and postoperative radiotherapy versus surgery alone for patients with stage I endometrial carcinoma: multicentre randomized trial. PORTEC Study Group. Postoperative Radiation Therapy in Endometrial Carcinoma. Lancet 2000;353:1404-1411.
- 2. Keys HM, Roberts JA, Brunetto VI ve ark. A phase III trial of surgery with or without adjunctive external pelvic radiation therapy in intermediate risk endometrial adenocarcinoma. A Gynecologic Oncology Group study. Gynecol Oncol 2004; 92: 744-751.
- 3. Mundt J, Lujan E, Rotmensch J ve ark. Intensity-modulated whole pelvic radiotherapy in women with gynecologic malignancies. Int J Radiat Oncol Biol Phys 2002; 52: 1330–1337.
- 4. Ahamad A, D’souza W, Salehpour M ve ark. Intensitymodulated radiation therapy after hysterectomy:comparison with conventional treatment and sensitivity of the normal-tissue–sparing effect to margin size. Int J Radiat Oncol Biol Phys 2005; 62: 1117–1124.
- 5. Roeske J, Lujan A, Rotmensch J, Waggoner SE, Yamada D, Mundt AJ. Intensity-modulated whole pelvic radiation therapy in patients with gynecologic malignancies. Int J Radiat Oncol Biol Phys 2000:8:1613–1621.
- 6. Lian J, Mackenzie M, Joseph K ve ark. Assessment of extended-field radiotherapy for stage IIIC endometrial cancer using three-dimensional conformal radiotherapy, intensity-modulated radiotherapy and helical tomotherapy. Int J Radiat Oncol Biol Phys 2008;70: 935–943.
- 7. Bouchard M, Nadeau S, Gingras LC ve ark. Clinical outcome of adjuvant treatment of endometrial cancer using aperture-based intensity-modulated radiotherapy. Int J Radiat Oncol Biol Phys 2008; 71:1343–1350.
- 8. Mundt AJ, Mell LK, Roeske JC. Preliminary analysis of chronic gastrointestinal toxicity in gynecology patients treated with intensity-modulated whole pelvic radiation therapy. Int J Radiat Oncol Biol Phys 2003; 56:1354- 1360.
- 9. Beriwal S, Jain K, Heron E, de Andrade RS, Lin CJ, Kim H. Dosimetric and toxicity comparison between prone and supine position imrt for endometrial cancer. Int J Radiat Oncol Biol Phys 2007; 67: 485–489
- 10. Heron DE, Gerszten K, Selvaraj RN, ve ark Conventional 3D conformal versus intensity-modulated radiotherapy for the adjuvant treatment of gynecologic malignancies: a comparative dosimetric study of dose-volume histograms small star, filled. Gynecol Oncol. 2003;91:39-45.
- 11. Salama J, Mundt J, Roeske J, Mehta N. Preliminary outcome and toxicity report of extended-field, intensitymodulated radiation therapy for gynecologic malignancies Int J Radiat Oncol Biol Phys 2006; 65: 1170–1176.
- 12. Nadeau S, Bouchard M, Germain E ve ark. Postoperative irradiation of gynecologic malignancies:improving treatment delivery using aperture-based intensity-modulated radiotherapy. Int J Radiat Oncol Biol Phys 2007; 68: 601–611.
- 13. E.B. Podgorsak: International atomic energy agency radiation oncology physics: a handbook for teachers and students, 2005.
- 14. Khan FM: The physics of radiation therapy, 3. ed., 2003
Details
| Other ID | JA27KF37YM |
|---|---|
| Journal Section | Research Article |
| Authors | |
| Publication Date | October 1, 2011 |
| Submission Date | October 1, 2011 |
| Published in Issue | Year 2011 Volume: 14 Issue: 4 |