Radiation therapy alone in elderly with early stage non-small cell lung cancer.

BACKGROUND: Radiation therapy (RT) alone is frequently used in elderly patients with medically inoperable early stage (I/II) non-small cell lung cancer (NSCLC). We retrospectively investigated the effectiveness of RT alone in this patient population treated in our institution. MATERIAL AND METHODS: Between 1995 and 1999, a total of 33 patients were treated with RT alone in our institution, all being males. RT doses ranged 66-78 Gy (median, 70 Gy) using standard fractionation (2.0 Gy per fraction). The age range was 71-97 years (median, 75 years) with 11 patients being >or=80 years old. Twenty-two (67%) patients had a squamous cell carcinoma. There were 24 (73%) stage I and nine (27%) stage II patients. RESULTS: Radiographic objective response rate was observed in 23 (70%) patients. The median survival time was 37.4 months and 3-year survival time was 50%, while the median cause-specific survival time was 48.1 months and a 3-year cause-specific survival rate was 55.3%. The median time to local recurrence was 36.8 months and a 3-year local recurrence-free survival rate was 50.2%, while the median time to distant metastasis was not achieved yet, the 3-year distant metastasis-free survival rate being 71.4%. One (3%) patient died of RT-induced acute lung toxicity, while only two (6%) patients experienced late grade 3 lung toxicity. No other high-grade toxicity was observed during this study. CONCLUSIONS: RT alone was effective and low toxic in elderly with early stage (I/II) NSCLC and could be considered as treatment of choice in this patient population.

Feasibility of an online adaptive replanning method for cranial frameless intensity-modulated radiosurgery.

To introduce an approach for online adaptive replanning (i.e., dose-guided radiosurgery) in frameless stereotactic radiosurgery, when a 6-dimensional (6D) robotic couch is not available in the linear accelerator (linac). Cranial radiosurgical treatments are planned in our department using intensity-modulated technique. Patients are immobilized using thermoplastic mask. A cone-beam computed tomography (CBCT) scan is acquired after the initial laser-based patient setup (CBCTsetup). The online adaptive replanning procedure we propose consists of a 6D registration-based mapping of the reference plan onto actual CBCTsetup, followed by a reoptimization of the beam fluences ("6D plan") to achieve similar dosage as originally was intended, while the patient is lying in the linac couch and the original beam arrangement is kept. The goodness of the online adaptive method proposed was retrospectively analyzed for 16 patients with 35 targets treated with CBCT-based frameless intensity modulated technique. Simulation of reference plan onto actual CBCTsetup, according to the 4 degrees of freedom, supported by linac couch was also generated for each case (4D plan). Target coverage (D99%) and conformity index values of 6D and 4D plans were compared with the corresponding values of the reference plans. Although the 4D-based approach does not always assure the target coverage (D99% between 72% and 103%), the proposed online adaptive method gave a perfect coverage in all cases analyzed as well as a similar conformity index value as was planned. Dose-guided radiosurgery approach is effective to assure the dose coverage and conformity of an intracranial target volume, avoiding resetting the patient inside the mask in a "trial and error" way so as to remove the pitch and roll errors when a robotic table is not available.