Simultaneous Integrated Boost (SIB) in Esophageal Cancer

Inclusion Criteria:

1. Histologically confirmed primary (non-recurrent) adenocarcinoma (AC) or squamous cell carcinoma of the esophagus or AC of the gastroesophageal (GE) junction.
2. Age \>/= 18.
3. Patients must be deemed unresectable disease or considered for a selective surgical approach (where surgery is delay if a patient achieves a complete response) as determined by the multidisciplinary evaluation or patient is not considered operable due to medical reasons.
4. Patients with distant metastasis and life expectancy \>/= 3 months are eligible.
5. ECOG Performance Status 0-2
6. No prior radiation to the thorax that would overlap with the current treatment field, prior radiation to other areas is allowed.
7. Patients with nodal involvement are eligible
8. Adequate bone marrow, and renal functions as assessed by the following: Hemoglobin \>/= 9.0 g/dl, Platelet count \>/= 100,000/mm\^3, Creatinine \</=1.5 times ULN
9. Ability to understand and the willingness to sign a written informed consent. A signed informed consent must be obtained prior to any study specific procedures.
10. Patients (men and women) of childbearing potential must use effective method of birth control throughout their participation in this study.
11. Induction chemotherapy is allowed.

Exclusion Criteria:

1. Patients with T1, N0 lesions.
2. Patients with a TE fistula or direct invasion into the mucosa of the trachea or major bronchi. Bronchoscopy is encouraged if a TE fistula is suspected. The presence of a fistula will exclude a patient from this study.
3. Prior surgery or radiotherapy for esophageal or gastroesophageal junction cancer.
4. Prior radiotherapy that would overlap the anticipated study treatment fields.
5. Patients with active second malignancy are allowed as long as it is determined that the treatment of esophageal cancer is a higher priority through proper subspecialty consultations.
6. Uncontrolled concurrent illness including, but not limited to: serious uncontrolled infection, symptomatic congestive heart failure (CHF), unstable angina pectoris, or psychiatric illness/social situations that would limit compliance with the study requirements.
7. Known hypersensitivity to docetaxel, 5-FU.
8. Any other condition or circumstance that would, in the opinion of the Investigator, make the patient unsuitable for participation in the study.