Stereotactic body radiotherapy for bilateral primary lung cancers: the Indiana University experience.

PURPOSE: To review the outcomes of 10 patients treated with stereotactic body radiotherapy for bilateral primary medically inoperable lung cancer. METHODS AND MATERIALS: Between July 2001 and February 2005, 10 patients were treated at Indiana University with stereotactic body radiotherapy for bilateral multiple primary lung cancers using a stereotactic body frame (Elekta, Stockholm, Sweden). Nine patients had cancers that were deemed inoperable secondary to multiple medical comorbidities. One patient refused surgery. All patients had biopsy proven non-small-cell lung carcinoma of at least one of their masses and presented with either metachronous or synchronous pulmonary nodules. Positron emission tomography scans were done for all patients before treatment. Radiation dose varied between 4800 and 6600 cGy given in 3 fractions prescribed to the 80% line covering at least 95% of the planning target volume. We performed a retrospective review of the outcome of these patients.
RESULTS: The mean follow-up time was 20.7 months and the median time was 18.5 months (range, 7-42 months). At the time of this review, all 10 patients were living. Eight (80%) of 10 patients had no evidence of disease progression. One patient developed distant metastasis 5 months after treatment and a second patient developed a local recurrence within the radiation field 11 months after treatment. Six patients had either acute or late pulmonary toxicity, but all toxicity was < or =Grade 2 as defined by the Radiation Therapy Oncology Group toxicity criteria.
CONCLUSION: Our preliminary results indicate that stereotactic body radiotherapy is a possibly safe and potentially effective treatment option for patients with bilateral multiple primary lung cancers that are deemed medically inoperable.