FAP-alpha-expressing tumors are a category of malignancies characterized by high expression of fibroblast activation protein alpha (FAP-α); a membrane-bound glycoprotein typically found in the surrounding stromal cells of various epithelial cancers. FAP-α is widely expressed across a large range of common cancers such as pancreatic, colorectal, lung, and breast cancers.
FAP-α is predominantly expressed in activated fibroblasts within the tumor microenvironment, playing a role in tumor growth, metastasis, and immune evasion. FAP-alpha-expressing tumors include various malignancies, notably pancreatic cancer, colorectal cancer, and some sarcomas.
Clinical symptoms vary widely based on tumor type and location but may include abdominal pain, weight loss, and gastrointestinal disturbances. Many patients remain asymptomatic until the disease reaches an advanced stage, making early detection challenging.
Diagnosis typically involves imaging studies (e.g., CT, MRI, PET scans) to identify tumors, alongside biopsies to confirm histological characteristics and assess FAP-α expression. Biomarker testing may aid in determining the tumor's aggressiveness and potential response to targeted therapies.
Treatment options depend on the specific tumor type and stage. Surgical resection is often the first-line treatment for localized tumors. For advanced disease, therapies may include chemotherapy, targeted therapies, and emerging immunotherapies that specifically target FAP-α-expressing cells.
Prognosis is influenced by factors such as tumor type, stage at diagnosis, and response to treatment, with overall survival rates varying widely. For example, pancreatic cancer has a 5-year survival rate of around 10%, reflecting the aggressive nature of many FAP-α-expressing tumors.
