Symptoms may result from local invasion or compression of adjacent thoracic structures such as compression involving the esophagus causing dysphagia, compression involving the laryngeal nerves causing hoarseness, or compression involving the superior vena cava causing facial edema and distension of the superficial veins of the head and neck. Symptoms from distant metastases may also be present and include neurological defect or personality change from brain metastases or pain from bone metastases. Infrequently, patients may present with symptoms and signs of paraneoplastic diseases such as hypertrophic osteoarthropathy with digital clubbing or hypercalcemia from parathyroid hormone-related protein. Physical examination may identify enlarged supraclavicular lymphadenopathy, pleural effusion or lobar collapse, unresolved pneumonia, or signs of associated disease such as chronic obstructive pulmonary disease or pulmonary fibrosis.
Treatment options for patients are determined by histology, stage, and general health and comorbidities of the patient. Investigations of patients with suspected NSCLC focus on confirming the diagnosis and determining the extent of the disease.
The procedures used to determine the presence of cancer include the following:
- Physical examination.
- Routine laboratory evaluations.
- Chest x-ray.
- Chest CT scan with infusion of contrast material.
Before a patient begins lung cancer treatment, an experienced lung cancer pathologist must review the pathologic material. This is critical because SCLC, which responds well to chemotherapy and is generally not treated surgically, can be confused on microscopic examination with NSCLC. Immunohistochemistry and electron microscopy are invaluable techniques for diagnosis and subclassification, but most lung tumors can be classified by light microscopic criteria.
Refer to the Staging Evaluation section of this summary for more information on tests and procedures used for staging.
Multiple studies have attempted to identify the prognostic importance of a variety of clinicopathologic factors.[6,14,15,16,17] Factors that have correlated with adverse prognosis include the following:
- Presence of pulmonary symptoms.
- Large tumor size (>3 cm).
- Nonsquamous histology.
- Metastases to multiple lymph nodes within a TNM-defined nodal station.[18,19,20,21,22,23,24,25,26,27,28] (Refer to the Evaluation of Mediastinal Lymph Node Metastasis section of this summary for more information.)
- Vascular invasion.[15,29,30,31]
Conflicting results regarding the prognostic importance of aberrant expression of a number of proteins within lung cancers have been reported. For patients with inoperable disease, prognosis is adversely affected by poor performance status and weight loss of more than 10%. These patients have been excluded from clinical trials evaluating aggressive multimodality interventions.
In multiple retrospective analyses of clinical trial data, advanced age alone has not been shown to influence response or survival with therapy.
Refer to the separate treatment sections for each stage of NSCLC in this summary for more information about prognosis.