A Phase II Study of Extended Field IMRT External Beam Irradiation and Intracavitary Brachytherapy
Status:
Terminated
Trial end date:
2013-01-01
Target enrollment:
Participant gender:
Summary
Recent studies have shown that the chance of survival among women with advanced cervical
cancer is increased when they receive concurrent chemotherapy and radiation to the pelvis.
However, patients who have advanced disease show loco-regional failure as well as a high
incidence of distant metastasis. Positron emission tomography (PET) scanning has high
sensitivity and specificity in the detection of pelvic and para-aortic lymph node metastases.
While the detection of para-aortic metastases by PET significantly impacts prognosis, PET has
been known to show positive lymph node metastasis in the pelvis only while not detecting
micrometastatic disease in the para-aortic lymph nodes (despite the fact that they are
histologically known).
In addition, patients with positive para-aortic lymph nodes on PET, greater amounts (more
than 45 Gy) of radiation must be used to improve the probability of controlling the cancer.
However, doses greater than this have been limited because of the dose and volume limits to
the small bowel. But, Intensity Modulated Radiation Therapy (IMRT) is a new way of
calculating and delivering radiation therapy. Compared to external beam radiation, IMRT has
the improved ability to deliver large doses of radiation to specific targets while minimizing
the exposure to surrounding normal tissue.
With IMRT, however, the effective dose/volume can be increased more safely and lower the
toxicity of surrounding tissue, thus making prophylactic dosing to para-aortic lymph nodes
not detected by PET safer and more effective.