Abstract 490P
Background
The transmembrane glycoprotein CD44, the major hyaluronan receptor, is considered to be involved in carcinogenesis. Its role as new therapeutic molecular target in solid tumors is under evaluation in clinical trials. The prognostic value remains controversial. Here, we aimed to investigate the correlation between CD44 expression and the clinicopathological features and survival of metastatic colorectal cancer (mCRC) patients (pts).
Methods
Data from 65 mCRC pts of the Medical Oncology Department-University Hospital of Cagliari were retrospectively collected from 2008 to 2021. The immunohistochemical analysis was performed at the Pathology Division-University Hospital of Cagliari on 3 μm thick sections obtained from paraffin blocks. Paraffin-tissue sections were immunostained with anti-human CD44 Rabbit monoclonal antibody (clone SP37). The immunointensity was subclassified into four groups as shown in the table. Statistical analysis was performed with MedCalc (survival distribution: Kaplan-Meier; survival comparison: log-rank test, association between categorical variables: Fisher's exact test).
Results
Pts median age was 66 years (range 49-85). Regarding CD44 expression: score was 0 in 18 pts, 1+ in 16 pts, 2+ in 17 pts and 3+ in 14 pts. Median Overall Survival (mOS) was 28.1 months (m) (95%CI: 21.3-101). Overexpressed CD44 (3+) was correlated with poor prognosis (p=0.0011; HR=0.2), with a mOS of 15.4 m (95% CI 8.5-35.9) versus 28.8 m (95%CI:24.8-101) in low CD44 expression (0, 1+, 2+). CD44 strong expression was associated with clinical poor prognostic features: 58.3% were ≥ 70 years old (p=0.03); 58.3% had inoperable disease (p=0.01); 91.7% had stage IV at diagnosis (p=0.1); 75% had synchronous metastases (p=0.4); BRAF was mutated in 9% of CD44 non-overexpressed vs 25% of CD44 3+ pts (p=0.1). Table: 490P
| CD44 expression | Score |
| Negative or weak membrane staining (MS) in < 10 % of tumor cells (TC) | 0 |
| Weak MS in ≥ 10 % of TC or moderate MS in < 10% of TC | 1+ |
| Moderate MS in ≥ 10% of TC or intensive MS in < 10% of TC | 2+ |
| Intense MS in ≥ 10% of TC | 3+ |
Conclusions
CD44 markedly correlated with aggressive tumor behavior and contributed to the progression of mCRC, thus suggesting its role as a novel prognostic marker and potential therapeutic target for mCRC pts.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
M. Scartozzi: Financial Interests, Personal, Speaker’s Bureau: Amgen; Financial Interests, Personal, Advisory Board: Amgen; Financial Interests, Personal, Other, Consultant: Amgen; Financial Interests, Personal, Speaker’s Bureau: Sanofy; Financial Interests, Personal, Advisory Board: Sanofy; Financial Interests, Personal, Other, Consultant: Sanofy; Financial Interests, Personal, Speaker’s Bureau: MSD; Financial Interests, Personal, Advisory Board: MSD; Financial Interests, Personal, Other, Consultant: MSD; Financial Interests, Personal, Speaker’s Bureau: Eisai; Financial Interests, Personal, Advisory Board: Eisai; Financial Interests, Personal, Other, Consultant: Eisai; Financial Interests, Personal, Speaker’s Bureau: Merk; Financial Interests, Personal, Advisory Board: Merk; Financial Interests, Personal, Other, Consultant: Merk; Financial Interests, Personal, Speaker’s Bureau: Bayer; Financial Interests, Personal, Advisory Board: Bayer; Financial Interests, Personal, Other, Consultant: Bayer. All other authors have declared no conflicts of interest.