Although much care is required in delivering extremely high doses of radiotherapy to the tumor, modified SIB radiotherapy was shown to be effective against extremely large tumors that could not be controlled using conventional radiotherapy. In future, an increase in the number of study patients and establishment of the technique will be required.

A clinical trial of radiotherapy with modified simultaneous integrated boost (SIB) technique against huge tumors was conducted. A 58-year-old male patient who had a huge pelvic tumor diagnosed as a rectal adenocarcinoma due to familial adenomatous polyposis was enrolled in this trial. The total dose of 77 Gy (equivalent dose in 2 Gy/fraction) and 64.5 Gy was delivered to the center of the tumor and the surrounding area respectively, and approximately 20% dose escalation was achieved with the modified SIB technique. The tumor with an initial maximum size of 15 cm disappeared 120 d after the start of the radiotherapy. Performance status of the patient improved from 4 to 0. Radiotherapy with modified SIB may be effective for patients with a huge tumor in terms of tumor shrinkage/disappearance, improvement of QOL, and prolongation of survival.

PurposeThe purpose of this study was to compare carbon-ion (C-ion), proton and photon radiotherapy (RT) plans with regard to dose reduction of the gastrointestinal (GI) tract by using a greater omentum spacer (GO spacer).MethodsWe retrospectively retrieved data for ten patients who received the GO spacer as surgical spacer placement for abdominal and pelvic tumors. Simulation plans were created on pre-spacer Computed Tomography (CT) and post-spacer CT for C-ion RT, proton RT and photon RT to compare the dose of the GI tract. The plans were normalized so that at least 95% of the planning target volume (PTV) received 70 Gy (relative biological effectiveness equivalent) delivered in 35 fractions. All plans were created with the lowest possible dose to the GI tract under conditions that meet the dose constraints for the PTV and spinal cord (maximum dose < 45 Gy). The part of the GI tract to be evaluated was defined as that most adjacent to the PTV. C-ion RT plans and proton RT plans were calculated by a spot scanning technique, and photon RT plans were calculated employing by fixed-field intensity-modulated radiation therapy.ResultsD2 cc and V10–70 of the GI tract were significantly lower on post-spacer plans than on pre-spacer plans for all three RT modalities. Regarding post-spacer plans, D2 cc of the GI tract was significantly lower on C-ion RT plans and proton RT plans than on photon RT plans (C-ion vs photon p = 0.001, proton vs photon p = 0.002). However, there was no significant difference between C-ion RT plans and proton RT plans for D2 cc of the GI tract (C-ion vs proton p = 0.992). In the photon RT plan for one patient, D2 cc of the GI tract did not meet < 50 Gy.ConclusionsThe GO spacer shows a significant dose reduction effect on the GI tract.

It is obvious that a CB has a great influence on cancer treatment decisions, but the effectiveness of the CB in our hospital should be verified in the future by analyzing treatment outcomes.

A randomized controlled trial assessing the effectiveness of professional oral care by dental hygienists.