Photodynamic therapy (PDT) that is based on the science of photochemistry has been recognized as a lung sparing local therapeutic modality that can achieve remarkable responses. It is an alternative treatment for early stage lung cancer patients who have poor lung function or multiple sites of cancer. Recently we treated a 70-year-old man who presented with squamous carcinoma in situ at a previous pneumonectomy site, and a 64-year-old man with a newly developed secondary superficial lung cancer, with PDT. There were no complications related to the procedure. Both patients had poor lung function due to prior lung cancer surgery. Clinical and histological complete remissions were achieved without any evidence of recurrence during 30 months of follow-up in both patients.