Clinical-dosimetric relationship between lacrimal gland dose and ocular toxicity after intensity-modulated radiotherapy for sinonasal tumours.

OBJECTIVE: To characterise the relationship between lacrimal gland dose and ocular toxicity among patients treated by intensity-modulated radiotherapy (IMRT) for sinonasal tumours. METHODS: 40 patients with cancers involving the nasal cavity and paranasal sinuses were treated with IMRT to a median dose of 66.0 Gy. Toxicity was scored using the Radiation Therapy Oncology Group morbidity criteria based on conjunctivitis, corneal ulceration and keratitis. The paired lacrimal glands were contoured as organs at risk, and the mean dose, maximum dose, V10, V20 and V30 were determined. Statistical analysis was performed using logistic regression and the Akaike information criterion (AIC). RESULTS: The maximum and mean dose to the ipsilateral lacrimal gland were 19.2 Gy (range, 1.4-75.4 Gy) and 14.5 Gy (range, 11.1-67.8 Gy), respectively. The mean V10, V20 and V30 values were 50%, 25% and 17%, respectively. The incidence of acute and late Grade 3+ toxicities was 23% and 19%, respectively. Based on logistic regression and AIC, the maximum dose to the ipsilateral lacrimal gland was identified as a more significant predictor of acute toxicity (AIC, 53.89) and late toxicity (AIC, 32.94) than the mean dose (AIC, 56.13 and 33.83, respectively). The V20 was identified as the most significant predictor of late toxicity (AIC, 26.81). CONCLUSION: A dose-response relationship between maximum dose to the lacrimal gland and ocular toxicity was established. Our data suggesting a threshold relationship may be useful in establishing dosimetric guidelines for IMRT planning that may decrease the risk of acute and late lacrimal toxicities in the future. ADVANCES IN KNOWLEDGE: A threshold relationship between radiation dose to the lacrimal gland and ocular toxicity was demonstrated, which may aid in treatment planning and reducing the morbidity of radiotherapy for sinonasal tumours.

Clinical effect of meso-tetrahydroxyphenylchlorine based photodynamic therapy in recurrent carcinoma of the ovary: preliminary results.

This article addresses the use of meso-tetrahydroxyphenylchlorin-based photodynamic therapy (m-THPC-PDT) to treat recurrent gynaecologic malignancies of the ovary. Photodynamic therapy is an experimental approach in the treatment of neoplasms and results indicate it is a highly tissue selective, relatively simple intervention with few side effects, therefore reducing the overall burden on the patient. Of the three patients involved in the initial study, two were treated solely with photodynamic therapy by laparoscopy, and one underwent additional palliative debulking surgery of metastatic tumours. After a post-operative period of more than two years all three women remained free of relapses.