Immunotherapy is now a standard of care for first-line and eventually salvage therapy in patients with stage IV NSCLC and as adjuvant after RT-CT for stage III NSCLC.

The aim of the study is determining the therapeutic landscape and the reason for immunotherapy cessation.

Patients with stage IV or unresectable not irradiable stage III NSCLC will be registered at the time receiving immunotherapy alone or in combination with chemotherapy.

When IO is stopped, reason for cessation and further treatment will be recorded.

Secondary endpoints are survival after IO cessation, activity of first salvage therapy, disease-free survival after IO cessation in patients receiving no further treatment.

Patients will be centrally registered at the ELCWP headquarter (Institut Jules Bordet, Brussels, Belgium).

Inclusion Criteria:

• Histological diagnosis of non-small cell lung cancer (NSCLC)
• Stage IVA/IVB and unresectable and non irradiable stage III NSCLC naïve of immunotherapy.
• Patients who receive immunotherapy (any type) monotherapy, combined immunotherapy or in combination with chemotherapy for first or second-line treatment.
• Availability for participating in the detailed follow-up of the protocol.
• Signed informed consent.

Exclusion Criteria:

• Patients receiving adjuvant immunotherapy for stage I-III NSCLC are not eligible
• Tumours for which TNM stage at time of study inclusion cannot be assessed.
• History of prior malignant tumour, except non-melanoma skin cancer or in situ carcinoma of the cervix or of the bladder or cured malignant tumor (more than 5-year disease free interval).
• Any type of immunotherapy for previous cancer

Stage IV or unresectable and non irradiable NSCLC, naïve of immunotherapy and receiving immunotherapy alone or combined chemo-immunotherapy