To evaluate treatment efficiency after radiotherapy treatment with PET/CT results for non small cell lung cancer patients.

Purpose: The aim of this study is to evaluate operated or non-operated patients who were non small cell lung cancer and treated with either radio-chemotherapy or radiotherapy alone using PET/CT results.Materials and Methods: 39 lung cancer patients who were treated with or without operated methods were prospectively evaluated from April 2009 to February 2011. The study was approved by ethics comittee. Histopathological diagnosis of all patients in our study group were diagnosed by biopsy. All cases were staged according to 6 th edition of American Joint Committee on Cancer (AJCC). PET/CT was performed for patients to investigate prestaging, restaging and distant metastasis and it was used for treatment planning. Previous results were compared with the results taken three months later after treatment.Results: Of the 39 patients evaluated three (7.6%) were female and 36 (92.3%) were male. The mean follow-up period of the patients was 14.4 months. The mean age was 57.4 years. (Range: 36-79). Histopathologically, 14 (35.9%) of the patients were adenocarcinoma, 17 (43.6%) were squamous cell carcinoma, two (5.1%) were large cell carcinoma, and six (15.4%) were NSCLC cases with undetermined subtype. There were 26 (66.7%) patients in stage IIIA group, 11 (28.2%) patients in stage IIIB group, and 2 (5.1%) patients in stage IIB group. Seven (17.9%) complete responsive, 14 (35.9%) partially responsive, 16 (41%) progressive disease, and two (5.1%) stable disease cases were reported. The median value of SUVmax was 11 before the treatment. It is determined that survival is better in <11 patients than > 11 patients (p = 0.008). In patients whose PET response is complete metabolic response (p = 0.018), partial response (p = 0.009) and progressive disease (p = 0.005); the difference between patients with postRTSUVmax and preRTSUVmax.were significant. Finally, when survival assesment is made with respect to PET/CT response, a significant difference is determined between patients with complete response and the others ,on the edge (p = 0.090-p = 0.079). There is a significant difference in favor of the patients whose mass size after treatment over mass size before treatment percentage is smaller than 50% (p = 0.05). A statistically significant difference is determined in favor of patients who received induction cemotheraphy (p = 0.006). Effect of performance status on survival is determined to be significant in Cox survival analysis (p = 0.002).Conclusion: It couldn?t be determined a significent correlation between SUVmax and the sub-histopathologic tumor types, stage, age, gender and operative status. It is determined that performance status and the patients received induction chemotherapy was statistically significant, and the patients with complete response had better survival rates with a significance on the edge. In our group of patients mainly with local advanced stage, it is determined a significent difference between before treatment SUVmax values and prognosis.In addition, no significant effect on survival seen in the mass size, number of patients in our study despite the small number of metabolic response evaluation of short-term evaluation of treatment response is important, although the value of SUVmax, visible mass the size of the combined response evaluation by computed tomography revealed the need for the establishment of standards to evaluate.Key Words: Non small cell lung cancer, PET/CT, radiation theraphy, response, SUVmax.