Objectives: In presence of lung cancer, the additional impact of comorbidity on survival is often neglected, although comorbidities are likely to be prevalent. Our study examines the comorbidity profile and the impact of distinct conditions on survival in German lung cancer patients.Material and methods: We investigated claims data from a large nationwide statutory health insurance fund of 16,202 patients initially diagnosed with lung cancer in 2009. We calculated the prevalence of comorbidities grouped according to an extension of the Elixhauser Comorbidity Index (EI). Effects of distinct comorbidities on 5-year survival were examined using multivariate Cox proportional hazards models, adjusted for sex, age and metastases at baseline. Ail analyses were stratified by initial lung cancer-related treatment regimen (Surgery, Chemotherapy/Radiotherapy, No treatment). Findings were visualized in the form of a comorbidome.Results: Our study population was predominantly male (70.6%) with a mean age of 68.6 years, and a mean EI score of 3.94. Patients without treatment were older (74.4 years), and their comorbidity burden was higher (mean EI = 4.59). Median survival varied by subgroup (Surgery: 24.4 months, Chemotherapy/Radiotherapy: 8.8 months, No treatment: 2.0 months), and so did the comorbidity profile and the impact of distinct conditions on survival. Generally, the effect of comorbidities on survival was detrimental and the negative association was most pronounced for 'Weight Loss' and' Paralysis'. In contrast, 'Lipid Metabolism Disorders' and 'Obesity' were positively associated with survival. Noteworthily, highly prevalent conditions tended not to show any significant association.Conclusion: We found specific comorbidity profiles within the distinct treatment regimens. Moreover, there were negative but also some positive associations with survival, and the strength of these effects varied by stratum. Particularly the positive effects of 'Obesity" and 'Lipid Metabolism Disorders' which were robust across strata need to be further investigated to elucidate potential biomedical explanations.