Proton Beam Therapy for Patients with Medically Inoperable Stage I Non-small-cell Lung Cancer at the University of Tsukuba

Purpose: To evaluate in a retrospective review the role of proton beam therapy for patients with medically inoperable Stage I non-small-cell lung cancer (NSCLC).

Patients And Methods: From November 2001 to July 2008, 55 medically inoperable patients with Stage I NSCLC were treated with proton beam therapy. A total of 58 (T1/T2, 30/28) tumors were treated. The median age of study participants was 77 years (range, 52-86 years). A total dose of 66 GyE in 10 fractions was given to peripherally located tumors and 72.6 GyE in 22 fractions to centrally located tumors.

Results: The rates (95% confidence interval) of overall and progression-free survival of all patients and of local control of all tumors at 2 years were 97.8% (93.6-102.0%), 88.7% (77.9-99.5%), and 97.0% (91.1-102.8%), respectively. There was no statistically significant difference in progression-free rate between T1 and T2 tumors (p = 0.87). Two patients (3.6%) had deterioration in pulmonary function, and 2 patients (3.6%) had Grade 3 pneumonitis.

Conclusion: Proton beam therapy was effective and well tolerated in medically inoperable patients with Stage I NSCLC.