Tumour- and non-tumour associated long-term survival hazards in lung cancer patients with or without neo-adjuvant and/or adjuvant chemotherapy

Background:

The positive impact of neo-adjuvant and/or adjuvant chemotherapy on tumour-free 5-year survival in lung cancer patients has been documented. There are few data, however on long-term influence of chemotherapy on tumour- and non-tumour related survival.

Material and Method:

We retrospectively analysed 338 patients (males: 225 [65,8%), females: 117 [34.2%]) who had curative resection for non-small-cell lung cancer between 1/2003 and 12/2007. 113 had induction chemotherapy and/or adjuvant chemotherapy, 224 patients had surgery only. The postoperative tumour-stages were T0: 3(1%); T1: 174 (55%), T2:119 (37%), T3:16 (5%), T4: 7(2%), with a prevalence of higher stages in the chemotherapy group (chi2-test: p < 0.001). N-stages were N0: 188(59%), N1: 89(28%), and N2 42(13%), with a significant difference between both groups (p < 0.001). We applied a multivariable Cox proportional hazards model to evaluate prognostic significance of clinical covariates. Survival and hazard functions were calculated with a flexible parametric model (Royston-Parmar model).

Result:

For 10-year survival, multivariate analysis revealed T (p < 0.001) and N (p < 0.001), but not chemotherapy (p = 0.301) as significant prognosticator. When analysis was limited to death due to tumour, similar results were obtained (T [p = 0.004], N [p < 0.001], chemotherapy [p = 0.969]). Limiting the analysis to non-tumour-related death, T and N were no longer significant (p = 0.078 and p = 0.326, respectively), whereas chemotherapy turned out as a favourable parameter (p = 0.035). This was still valid when ASA was included as an additional probably confounding aspect (ASA p = 0.002, chemotherapy p = 0.023). The Royston-Parmar model showed lower hazards for non-tumour-related death in the chemotherapy group. In a multivariate model, chemotherapy was no longer significant (p = 0.359), while age turned out as a significant risk factor for non-tumour-related death (p = 0.004).

Fig. 1

Conclusion:

There is no evidence that neoadjuvant and/or adjuvant chemotherapy in non-small-cell lung cancer has a negative long-term prognostic impact on tumour-related or non-tumour-related death. It seems to be associated with reduced non-tumour-related death, which could not be explained by lower ASA, but by the younger age of the patients who had received chemotherapy.