Lucia Giaccherini

Radiotherapy (RT) is a treatment option for advanced biliary tract cancer (BTC), often combined with sequential and/or concurrent chemotherapy. The use of modern RT techniques requires accurate clinical target volume (CTV) definition and delineation. However, guidelines for CTV delineation in BTC are lacking. Therefore, the aim of this study was to propose a computer tomography (CT) atlas for CTV definition of BTC. We previously proposed guidelines to define the nodal CTV (CTV‑N) in BTC. In this study, based on a literature analysis, we defined the margins to be added to the gross tumor volume (GTV; subclinical and microscopic disease) to define the primary tumor CTV (CTV‑T). An abdominal contrast enhanced planning CT scan was performed on three different patients with unresectable intrahepatic cholangiocarcinoma (CC), extrahepatic CC and gallbladder cancer. The GTV and anatomical reference structures were outlined on CT images. Then, based on our guidelines, the CTV‑T and CTV‑N were delineated and merged to define the final CTV in the three patients. An atlas, showing the defined CTV, was generated from the reference CT images to illustrate the CTV for intra‑hepatic CC, extra‑hepatic CC and gallbladder cancer. This atlas can be used as an aid for CTV definition in patients with BTC treated with modern RT techniques.

Background/Aim: The Vienna Rectoscopy Score (VRS; from 0, absence of rectal mucosal changes, to 5) assessed 1 year after radiotherapy is a surrogate end-point of late rectal toxicity. The aim of this study was to investigate the association between treatment-related factors and 1-year VRS. Patients and Methods: We performed a retrospective analysis of prospectively collected data. Patients with prostate adenocarcinoma treated with definitive or postoperative radiotherapy (RT) underwent endoscopy 1 year after RT. Relationships between VRS of 2 or more and treatment parameters were investigated by univariate and multivariate logistic analyses. Results: One hundred and ninety-five patients (mean age=69 years; range=43-81 years) were considered eligible for the study. At univariate analysis, patients treated with hypofractionation plus radiosurgery boost (p<0.001) and an equivalent dose in 2 Gy per fraction (EQD2) (α/β=3) ≥75 Gy (p<0.001) was associated with a significantly higher incidence of VRS ≥2 after 1 year of follow-up. At multivariate analysis, radiosurgery boost was an independent risk factor for developing rectal mucosal lesions (VRS ≥2), yielding an odds ratio (OR) of 4.14 (95% confidence interval (CI)=1.2-13.8), while pelvic surgery was inversely associated with VRS ≥2 (OR=0.39; 95% CI=0.17-0.94). Conclusion: Hypofractionation followed by radiosurgery boost significantly increased the risk of developing late-onset rectal mucosal changes. Therefore, special care and preventative treatment strategies are needed when using radiosurgery boost after hypofractionated RT.

Background/Aim: Radiotherapy is a treatment option for both adjuvant and neo-adjuvant settings for biliary tract cancer. Guidelines on the delineation of the target volume of lymph nodes are lacking; only generic indications are available, without specific recommendations for different primary tumour locations (e.g. intrahepatic, extrahepatic biliary tract or gallbladder cancer). The aim of this study was to systematically review available literature to provide recommendations on lymph node target volume delineation in patients with unresectable biliary tumour. Materials and Methods: A systematic search of electronic databases was performed up to July 2016. The primary outcome measure was the rate of lymph node involvement according to the location of primary biliary tumour. Sites with ≥5% of nodal metastases were considered in the clinical target volume for radiotherapy planning. Results: Twelve studies (1075 patients) were included. The most frequent site of lymph node metastasis in intrahepatic biliary tree carcinoma was retroportal (61.1%, 95% confidence interval (CI)=50.7-70-6%). Other frequently involved lymph nodes were along the hepatoduodenal ligament [frequency=38.7%, 95% CI=31.0-47.0%], those along the common hepatic artery (17.0%, 95% CI=8.2-31.9%) and the hilar nodes (16.9%, 95% CI=13.2-21.4%). In extrahepatic biliary tree cancer, the most frequently involved lymph nodes were the pericholedochal (42.7%, 95% CI=33.8-52.1%) and those along the hepatoduodenal ligament (40.3%, 95% CI=32.4-48.8%). Other commonly involved nodal regions included retroportal lymph nodes (30.9%, 95% CI=23.0-40.1%), pancreaticoduodenal anterior and posterior nodes (30.1%, 95% CI=12.2-57.1%), those along the common hepatic artery (19.7%, 95% CI=11.8-31.0%) and para_aortic nodes (15.2%, 95% CI=8.0-27.0%). The most common site of metastases in gallbladder cancer were the pericholedochal nodes (25.2%, 95% CI=18.6-33.2%), those along the cystic duct (23%, 95% CI=16.6-30.8%), and retroportal nodes (17.1%, 95% CI=11.6-24.5%). Conclusion: Biliary tract cancer has a high propensity for regional lymphatic metastases. An evidence-based nodal target definition of biliary tract cancer based on primary tumour location was proposed.