Nimotuzumab With Radiotherapy in the Treatment of Anal Canal Cancers

Inclusion Criteria: For both step I and II: * Patients with histologically confirmed squamous cell carcinoma of the anal canal * Aged 18 years or older * ECOG: 0-1-2 * Adequate contraception in women of child-bearing potential and for men * Ability to understand and the willingness to sign a written informed consent document. * HIV-positive patients with T1-2 anal canal tumors, or * Patients with anal canal tumors not eligible for conventional chemotherapy (for example, due to age and/or co-morbidities) * Patients who have already started radiotherapy for anal canal cancer For step II: * HIV-positive patients with T1, T2 anal canal tumors * HIV-negative patients not eligible for conventional chemotherapy (for example, due to age and/or co-morbidities) * HIV-negative patients with T1-2 anal canal cancer Exclusion Criteria: For both step I and II: * Patients receiving any other investigational agents * Previous treatment with anti-EGFR drugs * History of allergic reactions attributed to compounds of similar chemical or biologic composition to Nimotuzumab or other agents used in study. * Previously treated with pelvic radiotherapy. * Lesions not suitable for radiotherapy * Patients with uncontrolled hypercalcemia * Uncontrolled intercurrent illness * Pregnant or breast-feeding women * Any concurrent active malignancy * Patients with T3-4 anal canal tumors or patients with nodes positive. Step I: * HIV-negative patients with anal canal tumors that are judged suitable for current treatment consisting in radiotherapy and 5-FU and MMC chemotherapy