Bronchoscopy of non visible lesions in the lung, have a low diagnostic yield. The use of endoscopic ultrasound might increase the diagnostic yield. This prospective study randomises between bronchoscopy with the use of a ultrasound miniprobe and bronchoscopy without the use of a miniprobe in clinical practice at Haukeland University Hospital.

The study hypothesis:

The use of the ultrasound miniprobe will increase the diagnostic yield of bronchoscopy in non visible lesions.

Bronchoscopy is usually the primary investigation of lesions in the lung. X-ray fluorescence guides the sampling with brushing, biopsy or trans bronchial needle aspiration (TBNA) if the lesion not is visible. Ct guided trans-thoracic sampling will be performed if a the sample is non representative. This will delay the diagnosis, and trans-thoracic sampling has a higher risk of pneumothorax. The use of a ultrasound miniprobe might increase the diagnostic yield of bronchoscopy in non visible lesions. The ultrasound probe in a guide sheath is advanced to the lesion with use of X-ray fluorescence. When the lesion is visualised the miniprobe is removed and sampling is performed with TBNA, biopsy and brushing through the guide sheath. If rapid on site cytoevaluation is negative, new TBNA is performed. Previous trials have shown a diagnostic yield without ultrasound between 40-50% and with ultrasound between 60-80%. The studies with ultrasound have been performed by "super specialists". This study will evaluate bronchoscopy with the use of ultrasound miniprobe in clinical practice without "super specialists". It is a prospective randomised trial.

Inclusion Criteria:

• All patients with lesions suspicious of malignancy in the lung.

Exclusion Criteria:

• Patients with lesions assumed to be visible by bronchoscopy.
• Later proven visible lesion by bronchoscopy.
• Patients not able to be investigated by bronchoscopy.