Pancreatic cancer is a very aggressive disease and its prognosis is poor. Large proportion of patients diagnosed with pancreatic cancer is already in metastatic or locally advanced phases. Although there have been huge improvements in survival for many other cancers over the last few decades, the same isn't true for pancreatic cancer. Median 5-year survival rate for pancreatic cancer is around 10% and there are limited number of treatments approved for pancreatic cancer.

There is no definite consensus on the best second-line chemotherapy for patients with metastatic pancreatic cancer who have progressed after first-line chemotherapy. The randomized phase III study, NAPOLI-1 trial has revealed that liposomal irinotecan (nal-IRI) plus fluorouracil/leucovorin (FL) regimen could be an acceptable treatment option in patients with metastatic pancreatic cancer who had been previously treated with gemcitabine-based chemotherapy.

In this study, The investigators will evaluate how the treatment landscape has been changed since the appearance of nal-IRI in Korea. By retrospectively comparing treatment efficacy and safety outcomes before (cohort 1; without nal-IRI/FL) and after the launch of nal-IRI (cohort 2; with nal-IRI/FL), investigators will identify the degree of improvement in treatment outcome brought about by nal-IRI and will confirm whether the nal-IRI could be applied as an effective treatment option in patients with metastatic pancreatic cancer who failed first-line chemotherapy.

Inclusion Criteria:

1. Patients initially diagnosed as locally advanced pancreatic cancer or metastatic pancreatic cancer and received chemotherapy between 2012 and 2021
2. Histologically or cytologically confirmed adenocarcinoma of exocrine pancreas
3. Documented metastatic disease; disease status may be measurable or non-measurable as defined by RECIST v1.1 guidelines
4. Locally advanced pancreatic cancer; disease status was defined by NCCN guidelines.
5. Recovered from the effects of any prior surgery, radiotherapy, or other antineoplastic therapy
6. At least 18 years of age

Exclusion Criteria:

1. Other histology (ex. Neuroendocrine tumor, etc.)
2. Cohort 2 (other regimens); Patients who received nal-IRI at least once after diagnosis

In multiple medicatl center, such as Sinchon Severance hospital, Gangnam Severance hospital, Gachon University Gil hospital and Konkuk University hospital, investigators will collect the medical information according to inclusion criteria and exclusion criteria from 2012 to 2021.