FAP and small cell lung carcinoma: NSCLC shows FAP expression levels of up to 100% (in 344 NSCLC tissues examined [19], overall, FAP expression in tumour cells and its combination in tumour cells and CAFs were strongly associated with patient survival as useful predictive biomarkers for outcome), whereas small cell lung cancer and large cell neuroendocrine carcinoma are known to express FAP biomarker in up to 67%.