['colorectal cancer']
['raltitrexed combined with apatinib']

        Inclusion Criteria:

          -  1.Male or female, ≥ 18 of age;

          -  2.Histological confirmed advanced colorectal adenocarcinoma，and at least one
             measurable lesion;

          -  3.Have failed for ≥ 2 lines of standard chemotherapy(included Fluorouracil, irinotecan
             and oxaliplatin);

          -  4.ECOG performance status 0-2;

          -  5.Life expectancy of more than 3 months;

          -  6.The main organs function is well, and randomized within 14 days before the relevant
             inspection indicators to meet the following requirements:

               1. blood routine test Hgb ﹥90g/L, ANC﹥1.5×109/L, Platelets ﹥ 100×109/L,

               2. biochemical tests Serum Total bilirubin ≤ 1.5 X UNL(upper normal limit), ALT or
                  AST ≤ 2 xUNL, and ﹤ 5 x UNL（Hematogenous metastases）, Creatinine clearance rate≥
                  60 ml/min(Cockcroft-Gault formula),

               3. Doppler echocardiography assessment：LVEF ≥ 50%;

          -  7.No serious heart, lung, liver, kidney dysfunction; no jaundice and gastrointestinal
             obstruction; no acute infection;

          -  8.Signed informed consent;

          -  9.Good compliance, and family members agree to receive survival follow-up.

        Exclusion Criteria:

          -  1.Factors that could have an effect on oral medication (such as inability to swallow,
             chronic diarrhea and intestinal obstruction);
      