STK11 and sarcomatoid carcinoma: Furthermore, loss of LKB1 expression characterized also 33% (1/3) of the adenosquamous carcinomas, and in addition, the pleomorphic large cell carcinoma (100% (1/1)), the pleomorphic spindle cell carcinoma (100% (1/1)), and the large cell carcinoma included in our study (100% (1/1)) (p < 0.001).