Collection and evaluation of incidents in a radiotherapy department : a reactive risk analysis.

PURPOSE: to report on the use of an internal system for incident reporting. PATIENTS AND METHODS: from October 2001 until June 2009, data on incidents were collected in the radiotherapy department (RT) by means of an incident reporting worksheet. The risk analysis was based on the US Navy method of mishap cause investigation, the Human Factors Analysis and Classification System (HFACS). RESULTS: 37 incidents over 5,635 treatments were collected. Of the incidents, 20 involved deviation of the dose to the patient; only 6 showed clinical evidence of overdosage, while 2 of them showed permanent evidence of overdosage. There were 24 incidents that were classified as near misses (NM). Incorrect data input and use of an incorrect treatment field were the most common causes of the registered incidents. Reactive risk analysis showed how skill-based errors were associated with attention failure at the unsafe act level. Dose prescription and dose calculation are the most critical phases of the entire process. Most of the errors were discovered in set-up/treatment and during treatment visit/follow-up phases. The highest number of correction procedures was necessary in the phases of dose prescription and dose calculation. CONCLUSION: collecting and analyzing internal incidents improves the operative procedures used in the department.

Incidents analysis in radiation therapy: application of the human factors analysis and classification system.

The purpose of this investigation was to analyse incidents discovered in our radiation therapy department by means of human factor analysis and classification system (HFAC S). We adapted the original framework of the HFAC S and apply it to the analysis of incidents discovered in our radiotherapy department during a five-year period. Results showed that recurrent causal factors of incidents were attention failures and distracted/overconfidence behaviour as well as loss of situational awareness and mental fatigue. In our radiation therapy department the HFAC S allowed to highlight recurrent errors causal factors. Consequently we defined corrections factors for operators behaviour and implemented an operational protocol which improve operators attitude.

Three-dimensional conformal radiotherapy for locally advanced (Stage II and worse) head-and-neck cancer: dosimetric and clinical evaluation.

PURPOSE: To evaluate the dosimetric parameters of three-dimensional conformal radiotherapy (3D-CRT) in locally advanced head-and-neck tumors (Stage II and above) and the effects on xerostomia. METHODS AND MATERIALS: A total of 49 patients with histologically proven squamous cell cancer of the head and neck were consecutively treated with 3D-CRT using a one-point setup technique; 17 had larynx cancer, 12 oropharynx, 12 oral cavity, and 6 nasopharynx cancer; 2 had other sites of cancer. Of the 49 patients, 41 received postoperative RT and 8 definitive treatment. Also, 13 were treated with cisplatin-based chemotherapy before and during RT; in 6 cases, 5-fluorouracil was added. The follow-up time was 484-567 days (median, 530 days). RESULTS: One-point setup can deliver 96% of the prescribed dose to the isocenter, to the whole planning target volume, including all node levels of the neck and without overdosages. The mean dose to the primary planning target volume was 49.54 +/- 4.82 Gy (51.53 +/- 5.47 Gy for larynx cases). The average dose to the contralateral parotid gland was approximately 38 Gy (30 Gy for larynx cases). The maximal dose to the spinal cord was 46 Gy. A Grade 0 Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer xerostomia score corresponded to a mean dose of 30 Gy to one parotid gland. A lower xerostomia score with a lower mean parotid dose and longer follow-up seemed to give rise to a sort of functional recovery phenomenon. CONCLUSION: Three dimensional-CRT in head-and-neck cancers permits good coverage of the planning target volume with about 10-11 segments and one isocenter. With a mean dose of approximately 30 Gy to the contralateral parotid, we observed no or mild xerostomia.