Lung Cancer.pdf

8 J.B. Putnam, Jr., F.V. Fossella, and R. Komaki
It is hoped that a prospective randomized trial of lung cancer screening
using low-resolution CT of the chest will be conducted to objectively measure
the survival benefits of this approach compared to chest radiography
alone.
Staging
Lung cancer staging allows physicians to group patients on the basis of
the extent of disease and the expected survival so that appropriate therapy
can be applied in a systematic manner. Staging also assists physicians in
counseling patients and family members regarding potential therapy and
prognosis.
The staging system for lung cancer is the International System for Staging
Lung Cancer, which was adopted in 1986 and is supported by the
American Joint Committee on Cancer and the Union Internationale Contre
Le Cancer. The system was revised in 1997 (Mountain, 1997; Mountain and
Dresler, 1997) (Tables 1–1, 1–2, and 1–3). The stage categories were developed
through a process in which patients with similar survival were
grouped together and their clinical characteristics were examined (Mountain,
1997; Mountain and Dresler, 1997; Naruke et al, 2001). In the 1997 revision,
stage I disease was divided into stages IA and IB. In addition,
T3N0M0 disease was moved from stage IIIA to stage IIB since patients with
this type of disease have survival outcomes closer to those of other patients
with stage IIB disease.
NSCLC can be roughly grouped into 3 major categories on the basis of
treatment options. The first category consists of disease that is completely
contained within the lung and can be completely resected (stage I and II).
The second category consists of primary tumors that are resectable but are
associated with lymph node metastases or mediastinal involvement that
cannot be controlled with surgery (stage IIIA with N2 involvement and
stage IIIB). The third and final category consists of tumors associated with
distant metastases (stage IV disease); these tumors are not treated with
surgery except with palliative intent.
Despite our best surgical efforts, approximate 5-year survival rates by
stage for patients with NSCLC are as follows: stage I, 65%; stage II, 40%;
stage III, 15%; and stage IV, 5% (Nesbitt et al, 1995; Mountain, 1997;
Naruke et al, 1998) (see Table 6–1, page 103).
The role of staging in SCLC is discussed in chapters 10 and 11.
Pretreatment Evaluation
In patients with lung cancer, the goals of the pretreatment evaluation are
to determine the clinical disease stage (the final clinical stage determined
before the initiation of definitive therapy) and to determine the patient’s