Smoking and co-morbidity - it's impact on dose achievement in radio(chemo)therapy for HNSCC

Abstract

Smoking worsens the prognosis of patients with HNSCC. Furthermore, smoking is associated with the prevalence of co- and multimorbidity, so that it is assumed that not smoking per se, but co-/multimorbidity worsens the prognosis due to lack of compliance to therapy, e. g. by reducing the dose of the planned radio(chemo)therapy (RCT). However, data on this topic are currently sparse and contradictory, especially for HNSCC.Patient records and tumor documentation of 643 consecutive cases of the Head and Neck Tumor Center of the University Hospital Kiel were retrospectively evaluated. Patient characteristics and smoking habits were recorded and correlated with co-/multimorbidity and treatment course.The 643 patient files examined show that 113 (17.6 %) patients did not smoke, 349 (54.3 %) were active and 180 (28 %) patients had previously smoked. 315 (49 %) are treated exclusively by surgery; 121 (18.8 %) by surgery + adjuvant RCT and 72 (11.2 %) by surgery + adjuvant RT. 111 (17.3 %) receive a primary RCT and 24 (3.7 %) a primary RT. 131 (20.4 %) show co-/multimorbidity and 512 (79.6 %) do not. Smoking (> 10py) is significantly associated with comorbidity (p = 0.002). However, smoking and comorbidity, neither alone nor in combination, are correlated with the achievement of the target dose of RCT (p > 0.05).As expected, smoking is significantly linked to co-/multimorbidity. Dose reduction of R(C)T is just as frequent in active smokers and patients with co-/multimorbidity as in non-smokers and patients without co-/multimorbidity. Thus, smoking and co-/multimorbidity influence the prognosis in other ways than by interfering with planned therapy regimens.