Temporal bone carcinoma: a first glance beyond the conventional clinical and pathological prognostic factors

Temporal bone squamous cell carcinoma (TBSCC) is an uncommon, aggressive malignancy with a poor prognosis in advanced cases. The dismal outcome is partially related to: the lack of reliable clinical or pathological prognostic factors and the largely unstandardized surgical and integrated treatments adopted. There is an undeniable need for novel diagnostic/therapeutic strategies to improve the prognosis. The purpose of this critical review was to explore the level of available knowledge concerning the molecular markers involved in the biology of TBSCC that have a prognostic potential. The Pub-Med and Scopus electronic databases were searched without publication date limits for studies investigating molecular markers in cohorts of patients with primary TBSCC. The search terms used were: "temporal bone cancer", "temporal bone carcinoma", "temporal bone malignancy", "ear cancer", "ear carcinoma", and "ear malignancy". We decided preliminarily not to consider series with less than five cases. Nine retrospective case series of TBSCC were found in which different analytical techniques had been used to study the role of several biomarkers (HPV, vimentin, transforming growth factor β, CD105, RECK, matrix metalloproteinase-9, MASPIN, EBV, p16, TP53 mutation, pSTAT3, relaxin-2). CD105 expression (in tumor vessel endothelial cells) and MASPIN cytoplasmic expression (in carcinoma cells) were, respectively, found directly and inversely related with the neoplasm's recurrence rate. CD105 expression was also inversely related with disease-free survival in TBSCC. A future goal of such analyses should be to ascertain the radio- and chemo-sensitivity profiles of individual TBSCCs, enabling truly personalized therapies. A further, more ambitious goal will be to find targets for therapeutic agents that might prove crucial in improving the disease-specific survival for patients with advanced TBSCC.