Efficacy of Pemigatinib in Patients With Solid Tumors Characterized by an Alteration of the Gene FGFR in Tumor Cells

Alterations in the fibroblast growth factor receptor (FGFR) gene are involved in the development of cancer. These anomalies are found at very variable frequencies (from less than 1% to around 10%) in cancers of the bile ducts, bladder, uterus, brain, ovary, lung, airways, digestive tract, breast, etc. Pemigatinib is an anti-cancer drug that acts on cells with alterations in the FGFR gene. It is used in Europe to treat people with biliary tract cancer who carry a specific FGFR alteration. However, in various clinical trials, pemigatinib has shown interesting activity in a number of patients with different cancers presenting with an alteration in the FGFR gene. This treatment could therefore be effective in several types of cancer where an alteration in the FGFR gene is detected. The aim of this clinical trial is to learn if pemigatinib works to treat patients with recurrent and/or metastatic cancer (whatever the type of cancer excluding blood cancers and those already treated with pemigatinib) presenting an alteration in the FGFR gene. Patients will: * Take oral pemigatinig in 3-week cycles (every day for 2 weeks followed by one week without pemigatinib) as long as they benefit from it. * Visit the clinic once every 3 weeks for checkups and tests during the treatment period * Visit the clinic once every 3 months for checkups after stopping treatment for at least 12 months.