Comparison of computed tomography and magnetic resonance based target volume in brain tumors.

PURPOSE: This study was mainly framed to study the difference in tumor volumes as seen on computed tomography (CT) and magnetic resonance (MR) and their significance in planning. MATERIALS AND METHODS: Twenty-five patients with brain tumor of different diagnoses who underwent stereotactic radiotherapy were included in this study. CT and MR imaging was done for all the patients with 2.5 mm slice thickness. The CT tumor volume and MR tumor volume were measured and compared with each other. The center of mass (CM) of the tumor volume delineated on CT and MR were computed and the shift between the two CMs was determined. RESULTS: The mean and median volume of the tumor as measured from MR scans was 19.67 cc +/- 13.73 and 16.13 cc (range: 3.25 cc-50.37 cc). Similarly, the mean and median volume of the tumor as measured from CT scans was 15.05 cc +/- 10.13 and 11.63 cc (range: 3.0 cc-36.25 cc) respectively. The mean and median CM shift between CT and MR was 5.47 mm and 5.21 mm respectively. CONCLUSION: The study demonstrates that MR is an indispensable imaging modality in radiotherapy for planning brain tumors.

Experience with intraluminal radiotherapy in advanced oesophageal cancer.

Despite improvement in the diagnostic modalities, surgical technique, chemotherapy and radiotherapy, mortality and morbidity due to carcinoma esophagus continues to be dismal. Combination of external and intraluminal radio therapy (ILRT) has emerged as a powerful and promising palliative therapy in this disease. Thirty four patients with inoperable cancer esophagus treated with ILRT during June 1991 to December 1993 were evaluated to assess its palliative effects. Seventeen of these patients had received additional chemotherapy and external radiotherapy. Thirteen patients received only radiotherapy (both external radiotherapy + ILRT) and the remaining 4 received only ILRT. They were followed up for a mean period of 8.3 months (range 2 to 28 months) during which one patient was lost to follow up. Eight had a follow up of less than 6 months. Eight (33%) amongst the remaining 25 patients were considered disease free, 15 had recurrent and progressive disease, one developed metastasis and one patient died. In 21 (66%) dysphagia markedly improved. Nine (26%) patients survived beyond 1 year and the median survival for all patients was 8 months. Associated radiation morbidity was documented in 13 (38%) patients. We conclude that combination of external radiotherapy and ILRT is an effective and safe therapy for inoperable esophageal malignancies.

Role of radiation therapy in the treatment of benign ocular diseases.

Radiation therapy, although a prime treatment modality for malignant disease, has few definitive indications for some benign ocular diseases too. Orbital pseudotumour, Graves ophthalmopathy and pterygium are the conditions where the radiation oncologist has got an important role to play. This article reviews the current status of the role of radiation and its effectiveness in the management of these diseases.