You are in PORTALS Digital Radiography Intensity Modulated Radiotherapy of Upper Abdominal Malignancies

Intensity Modulated Radiotherapy of Upper Abdominal Malignancies

E-mail Print PDF


Intensity modulated radiotherapy IMRT

Upper abdominal malignancies present some of the most difficult types of cancer to effectively treat. And although radiation therapy plays a key role in the treatment of upper abdominal malignancies, the delivery of appropriate radiation doses is usually restricted by radiation sensitive normal structures in the upper abdomen; which consist of the kidneys, small intestine, stomach, liver, and spinal cord.

Intensity modulated radiotherapy (IMRT) provides a more conformal dose delivery system as opposed to the conventional radiation technique three-dimensional conformal radiotherapy (3DCRT). IMRT could possibly contribute to a better normal tissue sparing and dose escalation to these tumors, which has the ability to trim down toxicity and to improve local control.

Therefore the goal of this study was to evaluate and determine a possible dosimetric benefit of IMRT as opposed to 3DCRT, and to judge the impact of IMRT on acute toxicity. For this objective, IMRT and 3DCRT plans were conceived and applied for all patients and constraints of the dose distribution compared. All patients were treated with IMRT, and the acute toxicity evaluated on a weekly basis using the Common Terminology Criteria for Adverse Events (CTCAE) grading scale.

IMRT and 3DCRT plans were produced for 31 unselected successive patients with upper abdominal malignancies who were treated between January 2010 and March 2013.

Virtual simulation using positron emission tomography/computed tomography (PET/CT) was performed in 22 of 31 patients (71%), and traditional computed tomography (CT) simulation in nine patients (29%).

All patients were treated using linac-based step and shoot IMRT. Sixteen of 31 patients (51.6%) were administered definitive radiotherapy, while 15 patients (48.4%) received postoperative radiotherapy. Twenty-one of 31 patients (67.7%) received concomitant radio chemotherapy using 5-FU, gemcitabine or cisplatin-based regimen, and 10 patients (32.3%) only received radiotherapy. And acute toxicity was evaluated once a week using the Common Terminology Criteria for Adverse Events (CTCAE) grading scale version 4.0

When it came to the results, IMRT plans revealed a tiny yet statistically important improvement of the conformity index in comparison to 3DCRT plans (difference (95% confidence interval), -0.06 (?0.109 to-0.005); p= 0.03).

The uniformity index was not considerably improved (p = 0.10), but a notably reduced high dose volume on cost of a significantly increased low dose volume was taken into account for the kidneys. The acute toxicity appeared to be less than generally reported for the same patients treated with 3DCRT. No patient developed grade 3 or 4 non-hematological acute toxicity, and the most common grade 2 toxicity was vomiting (9.7%).

In conclusion, IMRT provides the possibility of a clinically pertinent and applicable dosimetric advancement as opposed to 3DCRT in regards of reducing acute toxicity. However, further maximization and optimization of the new radiotherapy method and accompanying clinical trails are needed before IMRT is habitually utilized for upper abdominal malignancies.

These signals are relayed buying clomid online safe which then is by a number of such as medial preoptic and paraventricular nulcei.