A Phase II Study of Simultaneous Modulated Accelerated Radiation Therapy Concurrent With Chemotherapy in Patients With Esophageal Squamous Cell Carcinoma
Esophageal cancer is one of the most common malignant diseases in China, especially in
Chaoshan region. Concurrent chemoradiotherapy is the standard non-surgical treatment method
for this disease and the radiation schedule is about 50.4~60 Gray (Gy) in total, 1.8~2Gy per
fraction generally. However, although with such comprehensive method, noncontrol of local
disease or recurrence is still the main reason of failure.
Most patients with esophageal cancer suffer from malnutrition. A number of factors including
hypoxic, inflammation, radioresistance and accelerated repopulation may contribute to local
failures of disease after treatment; therefore a higher radiation biological equivalent dose
(BED) will improve the local control probability. Although the intergroup 0123 (INT123)
trial had shown that simply increasing total radiation dose could not gain better local
control or overall survival rate, however, the ability of this trial to test the potential
benefits of higher radiation dose could be compromized by the deficiencies within them, such
as, observation bias,large radiated target volume and usage of conventional radiation
technique. In other words, the probability that increasing radiation may help improving the
control of disease should not be denied.
Modern radiation techniques, such as intensity modulation radiation therapy (IMRT),
specially, are able to improve the coverage of target volumes and sparing of critical
structures, while increase the total radiation dose. By using simultaneous modulated
accelerated radiation therapy (SMART) technique, the doses to the relevant normal organs per
fraction could be reduced significantly, while the doses to tumor could be increased to
higher than 2Gy. Thus reach the double goal of protection of normal tissues, increasing
total radiation Equivalent Uniform Dose (EUD). Dosimetric study has proven the feasibility
and superiority of SMART-base IMRT in radiation treatment of esophageal cancer, compared
with conventional technique.
Overall, SMART-base IMRT concurrent with chemotherapy may improve the local control and
overall survival rate of patients with esophageal cancer; Meanwhile, the acute and late
toxicities would be tolerable and slighter than that of conventional technique.
Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
The probabilities of grade ≥ 3 acute toxicities and 2-year late toxicities of esophagus and lungs.
The period during treatment and the 2 years after treatment
Chuangzhen Chen, MD
Cancer Hospital, Shantou University Medical College
China: Ethics Committee