Squamous cell carcinoma of the upper aerodigestive tract in exclusive smokers, chewers, and those with no habits

BACKGROUND: Tobacco consumption is the major risk factor for developing head and neck squamous cell cancer (SCC). The site of development of HNSCC may depend on the way the tobacco is consumed. While laryngeal cancers are more common among smokers, oral cancers are more common among tobacco chewers. Since the use of smokeless tobacco is increasing, it is important to know whether this difference is restricted only to site wise distribution or it has other clinical and pathological implications. PATIENTS AND METHODS: We analyzed a prospectively collected dataset of HNSCC patients other than nasopharyngeal cancers attending our outpatient department at a single unit of the head and neck services at Tata Memorial Hospital, Mumbai, India, between January 2010 and September 2011. There were 747 eligible patients and were divided into three groups: Those with chewing as the only habit (chewers), those with smoking as the only habit (smokers), and those with no habits. Patients with regular use of alcohol were excluded from the study. The clinical and pathological parameters were analyzed. RESULTS: Of the 747 patients, the tobacco chewers formed 69.3% followed by smokers (19.5%) and patients with no habits (11.1%). Majority of smokers were men (98%). Site distribution revealed patients with chewing as the only habit had oral cancers (most commonly gingivobuccal complex cancers) as the most common site and those with smoking as the only habit had larynx as the most common site. In patients with no habits, oral tongue was found to be the most common site. No statistically significant pathological differences were observed in between these groups in patients who underwent surgery (n = 366) at the initial modality of treatment. CONCLUSIONS: There is a direct relationship between the form of tobacco use and site of appearance of HNSCC. However, there are no differences in clinical or pathological parameters between HNSCC caused by tobacco chewing or tobacco smoking.