Inclusion Criteria:

- Patients with pTNM stage IIB or III (UICC Sixth version) primary colon cancer/rectal
cancer who have undergone surgery of histological curability A (including
laparoscopic surgery) (the curability is judged after surgery)

- Patients with primary tumor that directly invades other organs or structures and/or
perforates into the visceral peritoneum (T4) or with histologically positive lymph
node metastasis (N+) (to be judged after surgery)

- Patients who is between 20 and 80 years old at the time of obtaining informed consent

- Patients with performance status of 0 - 2

- Patients without receiving any cancer treatment such as radiation, chemotherapy, and
immunotherapy before surgical operation

- Patients without severe dysfunction of renal, hepatic, or bone marrow function

- Patients without serious complications such as bone marrow suppression, diarrhea, and
infections diseases

- Patients who have given consent to participate in this clinical study by
himself/herself or his/her family

Exclusion Criteria:

- Patients in whom the bottom of tumor reaches the peritoneal reflection

- Patients with lower rectal cancer (Rb), anal canal (P), or circumanal skin (E)

- Patients who has active multiple cancers or whose disease-free survival is less than
5 years even though the cancers are metachronous (except carcinoma in situ and skin
cancers)

- Women who are currently pregnant or wish to be pregnant during this clinical study

- Patients who are judged to be inappropriate to participate in this clinical study by
the investigator or subinvestigator