Lung Cancer.pdf

108 W.R. Smythe
hospitals for 149 patients with stage I NSCLC who were considered medically
inoperable. The mean radiation dose administered was 64.7 Gy. The
actuarial 3- and 5-year survival rates were 34.2% and 22.2%, respectively,
and the 5-year survival rate was 31% in a subgroup of patients who underwent
concomitant mediastinal nodal irradiation (Morita et al, 1997).
Another study retrospectively examined outcomes in 103 patients with
stage I and II NSCLC treated in the 1980s with “radical” radiation therapy
(~60 Gy delivered with curative intent). In this study, overall survival rates
at 3 and 5 years were only 35% and 14%, respectively; however, in a small
subgroup of patients with T1 tumors and no history of antecedent weight
loss, the survival rate at 5 years was 50% (Graham et al, 1995). An additional
71 patients receiving definitive radiation therapy for NSCLC secondary to
medical contraindications to surgical resection were reported by the radiation
therapy group here at M.D. Anderson. In this study, disease-specific
3-year survival rates following delivery of approximately 62 Gy were 47%
and 42%, respectively, for T1 and T2 lesions, and the local control rates were
89% and 61%, respectively. Finally, as a possible harbinger of things to come
in the field, a group of patients treated with proton-beam radiation therapy
between 1994 and 1998 was recently reported by Bush et al (1999). In this
study, the disease-free survival rate in patients with stage I disease at a median
follow-up time of 2 years was 86%.
These studies and many similar reports suggest that at best a 30% 5-year
survival rate should be expected in patients with stage I disease treated
with definitive radiation therapy. Wedge resection via a minimal incision
can lead to a 5-year survival rate of up to 50% in this same group of patients.
Although these data argue for limited surgical resection in patients
believed to be medically fit for surgery, the reader must take into account
that medically inoperable patients reported in earlier papers on definitive
radiation therapy often died of nononcologic causes, that disease-specific
survival after definitive radiation therapy may approach that after wedge
resection, and, finally, that the newer modalities of radiation therapy—
such as proton-beam therapy, motion-gated approaches, transthoracic intratumoral
treatment, and intensity-modulated radiation therapy—may
yet prove to be superior to current surgical techniques.
Chemotherapy
The 2 approaches taken for administration of chemotherapy to patients
with clinically resectable NSCLC have been preoperative (neoadjuvant)
and postoperative (adjuvant).
The adjuvant chemotherapy approach has been rigorously studied and
thus far has been shown to be of no significant benefit in patients with
NSCLC regardless of stage. A meta-analysis was performed by the Non–
Small Cell Lung Cancer Collaborative Group of England in 1995 examin-