For elderly patient, the treatment of Non Small Cell Lung Cancer was based on monotherapy but IFCT-0501 trial begun in 2006, demonstrated that a bitherapy (carboplatin and paclitaxel) is better than monotherapy in term of overall survival and progression free survival. The current recommendations are now to administer a carboplatin based bitherapy (4 or 6 cycles). After the treatment is stopped until progression and initiation of a second line treatment. The risk of this strategy is to be confronted to a rapid disease progression during the free interval. Indeed, about 1/3 of the patients whose disease was controlled after the chemotherapy do not receive 2nd line. The concept of maintenance is based on a continuous therapeutic pressure in order to preserve the therapeutic profit obtained by the treatment of 1st line (induction chemotherapy).

There is two types of maintenance :

• continuous maintenance therapy which consists in continuing the treatment initially associated with platinum until disease progression.
• switch maintenance which consists in introducing a new treatment after the end of induction chemotherapy The two types are validated by several trials. The marketing authorization of pemetrexed was enlarged to maintenance for non squamous carcinoma.

Gemcitabine has a good tolerance profile which make possible the use in a maintenance strategy. Several trials evaluated maintenance with this product and some show benefits in term of progression free survival.

The objective of this trial is to evaluate the switch maintenance in elderly patient with a controlled disease after 4 cycles of chemotherapy carboplatin-paclitaxel.

Inclusion Criteria:

• Histologically or cytologically documented Non Small Cell Lung Cancer non resectable or non irradiable stage III or stage IV
• EGFR wild type or non feasible EGFR
• 90 >Age ≥ 70
• ECOG Performance status : 0, 1 or 2
• Mini-Mental Test Status (MMS) > 23

Exclusion Criteria:

• Mixed non-small cell and small cell tumors
• Patients with EGFR mutated tumor
• Patient with EML4-ALK translocation
• Evolutive or symptomatic metastasis of central nervous system
• Superior vena cava syndrome
• Calcemia > 2,70 mmol/L