Non-small Cell Lung Cancer
Disease Staging/Prognosis
The staging of lung cancer is based on the size and invasiveness of the primary tumour (T), absence, presence and degree of regional lymph node (N) involvement, and the metastatic spread to distant organs and lymph nodes (M), or TNM system, and is applicable to the four major types of lung cancer.1 The grouping of patients into stages describes the relationship between the anatomical extent of the lung cancer (TNM system) and prognosis to provide an indication of the survival potential and suitability of different treatment strategies (Table 1).
Table 1. The staging of lung cancer and relationship to 5-year survival
| Stage | TNM Subset | Approximate 5-year survival(%) in clinically staged NSCLC16 | |||
| IA | T1 N0 M0 | 65.0 | |||
| IB | T2 N0 M0 | 42.5 | |||
| IIA | T1 N1 M0 | 40.0 | |||
| IIB | T2 N1 M0 | T3 N0 M0 | 27.5 | ||
| IIIA | T1 N2 M0 | T2 N2 M0 | T3 N1 M0 T3 N2 M0 |
15.0 | |
| IIIB | T1 N3 M0 | T2 N3 M0 | T3 N3 M0 | T4 N0 M0 T4 N1 M0 T4 N2 M0 T4 N3 M0 |
7.5 |
| IV | Any T any N M1 | <1.0 | |||
Thus, small tumours with little or no evidence of metastases (IA, IB and IIA) are associated with relatively high 5-year survival rates. As tumours become larger and more invasive, and there is greater involvement of the regional lymph nodes, so prognosis becomes worse (IIB, IIIA). For those with the largest tumours or with greatest nodal or metastatic involvement (IIIB and IV), the prognosis is particularly poor. The majority of lung cancer patients present with advanced stage IIIB or IV disease and, as curative therapy is not currently an option, clinical outcome is defined more appropriately by RR and progression free survival (PFS). The situation for the elderly and those with a poor performance status (PS) is exacerbated, as historically these patients are not generally considered to be suitable for intensive cytotoxic chemotherapy and therefore have lower survival rates.2,3
Patients with early-stage lung cancer may have few symptoms and experience few disease related effects on their quality of life (QoL). Late-stage or advanced NSCLC is associated with a number of symptoms arising from the local development of the tumour (e.g. bronchial obstruction and invasion of structures within the thorax) and other recognised effects of malignant disease. Thus, shortness of breath, cough, pain, loss of appetite and haemoptysis, as well as paraneoplastic effects such as weight loss, weakness and anorexia represent significant co-morbidities in advanced NSCLC with the potential to impact on QoL.4
References:
1. Mountain CF. The international system for staging lung cancer. Semin Surg Oncol 2000;18:106–15.
2. Govidian R. Management of patients with non-small cell lung cancer and poor performance status. Curr Treat Options Oncol 2003;4(1):55–9.
3. Lilenbaum R. Management of advanced non-small-cell lung cancer in elderly populations. Clin Lung Cancer 2003;5(3):169–73.
4. Plunkett TA, Harper PG. The importance of improving quality of life in patients with advanced NSCLC. Signal 2003;4(1):8–12.
