Smoking History Decreases Survival in Patients with Squamous Cell Carcinoma of the Mouth: A Retrospective Study with 15 Years of Follow-up

Document Type: Research Articles

Authors

1 Department of Dentistry, Unichristus, Rua João Adolfo Gurgel 133, Fortaleza, Ceará, Brazil.

2 Haroldo Juaçaba Hospital, Ceará Cancer Institute, Rua Papi Júnior, 1222, Rodolfo Teófilo, Fortaleza, Ceará, Brazil.

Abstract

Background: The purpose of this study was to evaluate the influence of smoking history on the clinical-pathological,
sociodemographic and prognostic characteristics of patients with oral squamous cell carcinoma (SCC).
Materials and Methods: A retrospective cohort study was carried out with the records of 136 smokers with SCC and
68 nonsmokers with oral SCC who were diagnosed and treated at Haroldo Juaçaba Hospital (2000-2014). Data on
patient sex, age, race, education level, tumor location, tumor size, lymph node involvement, distant metastasis, treatment
type, marital status, method of health care access (public or private health systems) and overall survival (15 years) were
analyzed by the X² test, Mantel-Cox tests and multinomial and Cox logistic regression models (SPSS 20.0, p <0.05).
Results: Smoking history was directly associated with male sex (p <0.001), low levels of education (p = 0.001), tumors of
the mouth and palate (p = 0.001), stage T3/4 tumors (p = 0.014), lymph node metastasis (N+) (p = 0.024), palliative
treatment (p = 0.024) and receiving health care through the public health system (p = 0.006), with education level
being the only independently associated factor (p = 0.039). Lower survival was observed in patients who were smokers
(p = 0,002), with low levels of education (p = 0.001), who had stage T3/4 tumors (p = 0.004), with N+ (p = 0.021), and
had received palliative treatment (p = 0.002). Age (>65 years old, p = 0.015) and T staging (T3/4, p = 0.033) decreased
the survival of SCC patients regardless of the other factors. Conclusions: Smoking history had an independent association
with low education level and a history of alcoholism, and survival was negatively associated with older age and larger
tumor size, which were more prevalent in smokers.

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