Radiotherapy to Patients With CA19-9-elevated Advanced Pancreatic Cancer

Inclusion Criteria:

* Ability to understand and the willingness to sign a written informed consent document.
* Age ≥ 18 years and ≤ 80 years.
* Eastern Cooperative Oncology Group (ECOG) performance status 0-2.
* Histologically or cytologically confirmed advanced pancreas adenocarcinoma.
* Patients who are not refractory to previous chemotherapy and who have not received radiotherapy.
* Locally advanced pancreatic cancer.
* Baseline serum CA19-9 \> 37 U/mL, and CA19-9 level within normal range (≤37 U/mL) after chemotherapy .
* Presence of at least of one measurable lesion in agreement to RECIST criteria.
* The expected survival ≥ 3 months.
* Adequate organ performance based on laboratory blood tests.
* Women of childbearing potential and men must agree to use adequate contraception prior to study entry and for the duration of study participation.

Exclusion Criteria:

* Pregnant or nursing women.
* Primary pancreatic cancer.
* Baseline serum CA19-9 ≤ 37 U/mL.
* The diagnosis was confirmed by pathology as non-adenocarcinoma of pancreas.
* Inflammation of the digestive tract, including pancreatitis, cholecystitis, cholangitis, etc.
* Severe and uncontrollable accompanying diseases that may affect protocol compliance or interfere with the interpretation of results.
* Renal insufficiency or dialysis
* Other serious accompanying illnesses, which, in the researcher's opinion, could seriously adversely affect the safety of the treatment.
* Patients who are allergic to oxaplatin or other chemotherapy drugs.
* Patients who are unwilling or unable to comply with study procedures.