Early squamous cell lung carcinoma: prognostic biomarkers for the many

When Aschoff published his landmark textbook Pathologische Anatomie in 1909,1 lung carcinomas were barely mentioned. Their classification into histological subtypes was also very basic as they were simply described as being ‘usually made up by cylindrical cells, rarely being medullary, colloid or cancroid’.2 Since then a lot has changed because of our increased knowledge and, unfortunately, because of a dramatic increase of cases of lung carcinoma following the epidemic of cigarette smoking. Now we know that, under the umbrella of lung carcinomas, there are several different neoplastic diseases.3 Squamous cell carcinomas (SCC) represent one of the major types of lung epithelial neoplasm, and three histological subtypes of invasive SCC are identified in the most recent WHO classification: keratinising, non-keratinising and basaloid3 plus the preinvasive ‘in situ’ type. Despite our advances in understanding the biology of these tumours, treatment for the largest group, the non-small cell lung carcinomas (NSCLC) of which SCC are part, it is still mainly guided by the tumour-node-metastasis (TNM) staging system, with surgery as first-line choice in early carcinomas (stages I, II and II according to the TNM system).4 Although curative in a number of people, surgical treatment eventually still fails in a large number of cases. Only 67% of patients with Stage IA survive 5 years, while just 25% are still alive, at the same time, if the stage is IIIA.5 The number of clinical trials evaluating the effect of adjuvant postoperative chemotherapy is therefore increasing to try to improve the outcome of surgery; however, the results are, so far, modest. When evaluating a patient for adjuvant treatment, the main predictive factor so far identified and currently used in clinical practice is still the TNM stage. Despite an increasing number of studies performed, no prognostic and/or predictive biomarkers have been …