ABSTRACT
PURPOSE: Differences in the delineation of the gross target volume (GTV) and planning target volume (PTV) in patients with non-small-cell lung cancer are considerable. The focus of this work is on the analysis of observer-related reasons while controlling for other variables. METHODS: In three consecutive patients, eighteen physicians from fourteen different departments delineated the GTV and PTV in CT-slices using a detailed instruction for target delineation. Differences in the volumes, the delineated anatomic lymph node compartments and differences in every delineated pixel of the contoured volumes in the CT-slices (pixel-by-pixel-analysis) were evaluated for different groups: ten radiation oncologists from ten departments (ROs), four haematologic oncologists and chest physicians from four departments (HOs) and five radiation oncologists from one department (RO1D). RESULTS: Agreement (overlap > or = 70% of the contoured pixels) for the GTV and PTV delineation was found in 16.3% and 23.7% (ROs), 30.4% and 38.6% (HOs) and 32.8% and 35.9% (RO1D), respectively. CONCLUSION: A large interobserver variability in the PTV and much more in the GTV delineation were observed in spite of a detailed instruction for delineation. The variability was smallest for group ROID where due to repeated discussions and uniform teaching a better agreement was achieved.
Subject(s)
Carcinoma, Non-Small-Cell Lung/radiotherapy , Lung Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted/methods , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Carcinoma, Non-Small-Cell Lung/pathology , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Observer Variation , Radiotherapy Dosage , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
BACKGROUND: Vinorelbine and docetaxel are active in anthracycline-pretreated, metastatic breast cancer. We compared their efficacy. PATIENTS AND METHODS: Patients were randomized to receive weekly vinorelbine (VIN) or weekly docetaxel (DOC), 6 weekly doses per 8-week cycle, with optional crossover (X-DOC vs. X-VIN. The primary end point was time to progression (TTP) on initial treatment. Remission induction, survival, and quality of life were secondary end points. RESULTS: Among 122 poor risk patients, a non-significant trend for better TTP was seen for DOC, both on initial and on crossover treatment. Responses were seen on either treatment, but progression was more common with VIN than with DOC, while more patients had a response with X-DOC than with X-VIN. Survival was identical in those receiving only the initial VIN vs. DOC and in the subgroups receiving crossover treatments. Grade 3-4 toxicity, especially hematological toxicity resulting in treatment delay, was more common with VIN. Non-graded toxicity contributed to abandoning DOC. Quality of life scores reflected worse results in patients crossing treatment arms, in either direction. CONCLUSIONS: DOC showed marginally better activity but did not improve TTP or other endpoints over VIN in this poor risk population.