ABSTRACT
Purpose: The PERYTON trial is a multicenter randomized controlled trial that will investigate whether the treatment outcome of salvage external beam radiation therapy (sEBRT) will be improved with hypofractionated radiation therapy. A pretrial quality assurance (QA) program was undertaken to ensure protocol compliance within the PERYTON trial and to assess variation in sEBRT treatment protocols between the participating centers. Methods and Materials: Completion of the QA program was mandatory for each participating center (N = 8) to start patient inclusion. The pretrial QA program included (1) a questionnaire on the center-specific sEBRT protocol, (2) a delineation exercise of the clinical target volume (CTV) and organs at risk, and (3) a treatment planning exercise. All contours were analyzed using the pairwise dice similarity coefficient (DSC) and the 50th and 95th percentile Hausdorff distance (HD50 and HD95, respectively). The submitted treatment plans were reviewed for protocol compliance. Results: The results of the questionnaire showed that high-quality, state-of-the-art radiation therapy techniques were used in the participating centers and identified variations of the sEBRT protocols used concerning the position verification and preparation techniques. The submitted CTVs showed significant variation, with a range in volume of 29 cm3 to 167 cm3, a mean pairwise DSC of 0.52, and a mean HD50 and HD95 of 2.3 mm and 24.4 mm, respectively. Only in 1 center the treatment plan required adaptation before meeting all constraints of the PERYTON protocol. Conclusions: The pretrial QA of the PERYTON trial demonstrated that high-quality, but variable, radiation techniques were used in the 8 participating centers. The treatment planning exercise confirmed that the dose constraints of the PERYTON protocol were feasible for all participating centers. The observed variation in CTV delineation led to agreement on a new (image-based) delineation guideline to be used by all participating centers within the PERYTON trial.
ABSTRACT
In this dosimetric comparison study it was shown that IMPT with robust planning reduces dose to surrounding organs in cervical and endometrial cancer treatment compared with IMRT. Especially for the para-aortic region, clinically relevant dose reductions were obtained for kidneys, spinal cord and bowel, justifying the use of proton therapy for this indication.
Subject(s)
Endometrial Neoplasms/radiotherapy , Proton Therapy/methods , Radiotherapy, Intensity-Modulated/methods , Uterine Cervical Neoplasms/radiotherapy , Female , Humans , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted , Treatment OutcomeABSTRACT
OBJECTIVE: To investigate the incidence of scalp metastases in high-risk breast cancer patients in order to assess whether caution is warranted with scalp cooling during adjuvant therapy. DESIGN: Observational study. METHODS: The incidence of scalp metastases and the disease course were studied in 885 very well evaluated high-risk breast cancer patients. These patients, who had at least four positive axillary lymph nodes, were treated in a randomised study with either classical chemotherapy, or the same chemotherapy followed by high-dose chemotherapy and autologous stem cell transplantation (the so-called N4+ study). RESULTS: After a median follow up of 110 months, 403 of the 885 patients (46%) had relapsed or developed metastases. 25 patients (3%) had developed skin metastasis; 4 of these patients (0.5%) had developed hairy scalp metastasis. The scalp metastases always occurred at the same time as or later than metastases elsewhere. CONCLUSION: Scalp metastases occur with a very low frequency and not as the first sign of metastatic disease. It is therefore unlikely that scalp cooling (to prevent baldness) decreases the local working of chemotherapy to such an extent that the risk of scalp metastases increases.
