ESSEUNO

S-1 Real-World is a prospective, observational, multicenter real-world study on the use of S-1 for patients with metastatic colorectal cancer (mCRC) after previous intolerance to 5-fluorouracil or capecitabine.

S-1 is associated with a lower incidence of cardiovascular toxicity (CVT) and hand-foot syndrome (HFS) compared to 5-FU/capecitabine, and is currently indicated for treatment of mCRC patients who are intolerant to such treatments. However, the real-world use of S-1 in Western patients with mCRC remains limited.

Real-world data (RWD) can provide clinicians and researchers with useful additional insights on the efficacy and safety outcomes of approved treatments within a broader, unselected population that closely reflects routine clinical practice. Additionally, these data can help increase clinicians’ familiarity with the specific drug and potentially support the expansion of current treatment indications.
In this study we aim to confirm the safety and feasibility of treatment with S-1 in patients unable to continue capecitabine- or 5-FU-based regimens because of CVT or HFS.

Adult patients with a diagnosis of mCRC, candidate to an S-1-based treatment regimen due to previous intolerance to capecitabine or 5-FU in terms of CVT or HFS.

Eligibility criteria:

• Willing and able to provide informed consent signed by study patient or legally acceptable representative, as specified by health authorities and institutional guidelines.
• ≥18 years of age.
• Histologically and/or cytologically documented diagnosis of mCRC.
• Previous intolerance to 5-FU or capecitabine due to CVT or HFS that developed in the adjuvant or metastatic setting.

S-1 is indicated as monotherapy or in combination with oxaliplatin or irinotecan, with or without bevacizumab, for the treatment of patients with metastatic colorectal cancer for whom it is not possible to continue treatment with another fluoropyrimidine due to hand-foot syndrome or cardiovascular toxicity that developed in the adjuvant or metastatic setting.

Primary objective of this study is to describe the safety of S-1-based treatment regimens in mCRC patients, administrated after previous intolerance to capecitabine or 5-FU.

Key Secondary Objectives

• To evaluate the antitumor efficacy and survival outcomes of S-1.
• To analyze treatment feasibility and its correlation with prior fluoropyrimidine therapy.
• To evaluate the impact of S-1 therapy on patients’ quality of life.