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Background This study compared manually delineated gross tumour volume (GTV) and automatically generated biological tumour volume (BTV) based on fluoro-deoxy-glucose (FDG) positron emission tomography (PET)/CT to assess the robustness of predefined PET algorithms for radiotherapy (RT) planning in routine clinical practice. Methods RT-planning data from 20 consecutive patients (lung- (40%), oesophageal- (25%), gynaecological- (25%) and colorectal (10%) cancer) who had undergone FDG-PET/CT planning between 08/2010 and 09/2011 were retrospectively analysed, five of them underwent neoadjuvant chemotherapy before radiotherapy. In addition to manual GTV contouring, automated segmentation algorithms were applied–among these 38%, 42%, 47% and 50% SUVmax as well as the PERCIST total lesion glycolysis (TLG) algorithm. Different ratios were calculated to assess the overlap of GTV and BTV including the conformity index and the ratio GTV included within the BTV. Results Median age of the patients was 66 years and median tumour SUVmax 9.2. Median size of the GTVs defined by the radiation oncologist was 43.7 ml. Median conformity indices were between 30.0–37.8%. The highest amount of BTV within GTV was seen with the 38% SUVmax algorithm (49.0%), the lowest with 50% SUVmax (36.0%). Best agreement was obtained for oesophageal cancer patients with a conformity index of 56.4% and BTV within GTV ratio of 71.1%. Conclusions At present there is only low concordance between manually derived GTVs and automatically segmented FDG-PET/CT based BTVs indicating the need for further research in order to achieve higher volumetric conformity and therefore to get access to the full potential of FDG-PET/CT for optimization of radiotherapy planning.

AIM: To evaluate the long-term outcome and prognostic factors of patients with hilar cholangiocarinoma. METHODS: Ninety-six consecutive patients underwent treatment for malignant hilar bile duct tumors during 1995–2005. Of the 96 patients, 20 were initially treated with surgery (n = 2 R0 / n = 18 R1). In non-operated patients, data analysis was performed retrospectively. RESULTS: Among the 96 patients, 76 were treated with endoscopic transpapillary (ERC, n = 45) and/or percutaneous transhepatic biliary drainage (PTBD, n = 31). The mean survival time of these 76 patients undergoing palliative endoscopic and/or percutaneous drainage was 359 ± 296 d. The mean survival time of patients with initial bilirubin levels > 10 mg/dL was significantly lower (P < 0.001) than patients with bilirubin levels < 10 mg/dL. The mean survival time of patients with Bismuth stage II (n = 8), III (n = 28) and IV (n = 40) was 496 ± 300 d, 441 ± 385 d and 274 ± 218 d, respectively. Thus, patients with advanced Bismuth stage showed a reduced mean survival time, but the difference was not significant. The type of biliary drainage had no significant beneficial effect on the mean survival time (ERC vs PTBD, P = 0.806). CONCLUSION: Initial bilirubin level is a significant prognostic factor for survival of patients. In contrast, age, tumor stage according to the Bismuth-Corlette classification, and types of intervention are not significant prognostic parameters for survival. Palliative treatment with endoscopic or percutaneous biliary drainage is still suboptimal, new diagnostic and therapeutic tools need to be evaluated.