[Show abstract][Hide abstract] ABSTRACT: The aim of this work was to analyze diagnosed cases of Oral Cancer (OC) and Oropharyngeal Cancer (OPC) in a Venezuelan population. We clinically evaluated 130 patients with OC and OPC and a histopathologic diagnosis of squamous cell carcinoma. The patients were analyzed according to gender age, and use of alcohol and tobacco and the tumors were classIfied based on anatomic location, staging parameters, and degree of difFerentiation. Ninety one patients (70%) were male and 39 (30%) were female. Patients' age ranged from 26 to 86 years old. Use of smoking tobacco, alcohol or both was reported by 84.3%, 49.1% and 45.4% of patients, respectively, and was more frequent in males. The most common oropharyngeal anatomic location was the base of the tongue (22.3%), followed by the tonsils (13.9%), while the most frequently affected oral location was the oral tongue (19.2%) followed by the gingiva and alveolar mucosa (10.8%), and the floor of mouth (7.7%). The majority of tumors (77.7%) were diagnosed at an advanced stage (Stage III or IV); metastasis to the regional lymph nodes occurred in 53.1% of cases. According to degree of diferentiation, well, moderately and poorly difFerentiated tumors accounted for 45.4%, 46.1% and 8.5% of cases, respectively. Well differentiated tumors accounted for 56.7% of OC cases, while the majority of OPC cases were classified as moderately or poorly differentiated (72.3%) (p < or = 0.002). Also, non-metastatic cases (NO) showed a predominance of well-diferentiated tumors (61.2%), while metastatic tumors (N+) were classified as moderately or poorly differentiated in 89.8% of cases (p < or = 0.0001). Our study population was characterized by a predominance of smokers and/or drinkers and a predilection for male patients. Most tumors were diagnosed at an advanced stage with a high incidence of metastatic spread to the regional lymph nodes, indicating possible delays in diagnosis. Less differentiated tumors were more frequently encountered among OPC cases and accounted for the vast majority of metastatic cases, supporting the prognostic value of assessing the degree of difFerentiation.