TITLE:
Radiotherapy Intensified by Increase of Fraction Size Using Three-Dimensional Conformal Radiotherapy in Bladder Preservation Therapy
AUTHORS:
Kiyoshi Ohara, Katsuhiko Oyama, Akiyoshi Suzuki, Keizo Kawano, Shinji Morimoto, Ayako Okawa
KEYWORDS:
Intensive Radiotherapy, Hypofractionation, Parallel Organ
JOURNAL NAME:
Journal of Cancer Therapy,
Vol.6 No.11,
October
23,
2015
ABSTRACT: Purpose: The impact of radiotherapy on bladder cancers heightened by
increase of fraction size using three-dimensional conformal radiotherapy
(3DCRT) was verified with biologically effective dose (BED, Gy10). Method: Twenty-five
patients who were considered unsuitable for total cystectomy underwent 3DCRT
between 2009 and 2014. When a gross tumor volume (GTV) did not neighbor guts
and the patient was cooperative to radiotherapy (radical), the GTV was treated
with a fraction size of ≥3.0 Gy, while a clinical target volume (CTV) of a
whole bladder and lymph nodes at small pelvis were treated with a conventional
fraction size of 2.0 Gy. When a GTV neighbored guts (palliative), only a CTV
was treated with an increased fraction size of 2.5 Gy. Results: Compared to
conventional two-dimensional radiotherapy, BED increased to 62.3 - 77.0 Gy10
(radical) or to 56.1 - 68.0 Gy10 (palliative) but the treatment period
shortened to 4 - 5 weeks. Acute adverse events (≤3 months), determined by
common terminology criteria for adverse events, were Grade 2 at most, but late
adverse events were not observed. Only one patient (6%) lost the bladder. Conclusions:
Patients who receive bladder preservation therapy appear good candidates to intensify
impact of radiotherapy with 3DCRT.