The project aims to compare the histopathological and molecular characteristics of tumour tissue from metastases with similar analyses of the primary tumour in the lung, where it is available.

The investigators will therefore perform analysis of blood samples if possible, to identify predictive markers in blood samples.

The investigators want to make genome analysis of tissue samples. This involves analysing the RNA, DNA methylation, for example in cancer cells. This will provide information regarding somatic changes in cancer cells, such as mutations. All of the investigators analysis will be cancer-focused, with the goal of increasing understanding of the heterogeneity.

The investigators will therefore perform analysis of blood samples if possible, to identify predictive markers in blood samples. This will then be the miRNA, RNA expression or protein expression in blood samples.

Inclusion Criteria:

• Patients with metastasizing lung cancer where further treatment is still applicable.

Exclusion Criteria:

• Terminal patients or patients in a reduced general condition with EGOC 3-4, i.e. patients who are confined to bed more than 50% of the day, with no clinical indication to perform sampling of the tumor and metastases.
• Patients where further cancer treatment is no longer applicable.
• Patients with cognitive impairment.
• Patients with inaccessible metastases where sampling may cause distress to the patient and are at increased risk of complications.