Symptoms and diagnosis of lung cancer

The lung is a deep organ, so signs of suffering come late. This explains why more than half of all patients are diagnosed when their cancer has already metastasized. 

Warning clinical signs are very diverse, and may be related to the tumour itself (respiratory distress, coughing, bloody sputum, persistent bronchitis, recurrent pneumonia....), with a locoregional extension of the tumor (pain in the chest wall or shoulder, headaches, edema of the face, neck and collarbone hollows, turgescence of jugular veins, difficult or blocked swalloing, altered speech, hiccups...) or with metastatic extension (fatigue, weight loss, loss of appetite, fever, headaches, paralysis, bone pain...). 

In the presence of any of these signs, especially in a person who is or has been exposed to smoking, a chest X-ray and/or CT scan should be prescribed. A normal chest x-ray does not fully eliminate the hypothesis of cancer, and this test must be followed by a chest scan if there is strong suspicion. 

If the clinical exam and the radiological exams suggest lung cancer, it is crucial to take a sample of the lesion via biopsy, to obtain histological or cytological proof. This is performed either by bronchial fibroscopy (a small tube inserted through the nose or mouth into the lung), or by puncture through the skin, guided by CT scan or ultrasound. Surgery is sometimes needed to take a sample of a lymph node in the mediastinum, or to perform a biopsy. 

Institut Curie has an integrated morphological and molecular diagnostic platform for microscopic analysis of tissue samples and high-throughput sequencing (NGS). These analyses enable us not only to understand the mechanisms of cancer development, but also to identify the most appropriate treatments as part of a precision medicine strategy, individualized for each patient, integrating standard treatment and clinical trial protocols. 

Finally, imaging (thoracic CT with iodine injection, brain CT or MRI, and positron emission tomography) is carried out to assess the extent of the disease, identify all lesions present in the body and thus define the therapeutic strategy.

Following the assessment of the spread of the disease, the disease will be classified at one of 4 stages: 

• Stage I: This is a localized cancer, smaller than or equal to 4cm, not affecting the regional lymph node and without metastasis 
• Stage II: This is a localized cancer, smaller than or equal to 4cm, and/or affecting the intra-pulmonary, peribronchial or hilum lymph node, but not affecting the regional lymph node, and without metastasis 
• Stage III: This is a locally advanced cancer since it has reached the mediastinum lymph node and/or has entered the mediastinum or the chest wall 
• Stage IV: This is a cancer with at least one metastasis.