Reirradiation of primary brain tumours: survival, clinical response and prognostic factors.

BACKGROUND AND PURPOSE: First, the aim was to determine the survival and quality of life after reirradiation of relapsing primary malignant brain tumours. The second aim was to assess the influence of a set of potentially prognostic factors on survival. MATERIALS AND METHODS: Forty-two patients received reirradiation for recurring primary brain tumours. The interval between the two consecutive treatments was at least 1 year. External beam irradiation for the initial and recurrent tumour was usually delivered with two opposing lateral fields or two wedged fields in orthogonal directions. The median physical doses of the first and second radiation course were 50 and 46 Gy, respectively. The median cumulative biological equivalent doses (BED) were 200.4 (alpha/beta = 2 Gy) and 115.2 Gy (alpha/beta = 10 Gy). During follow-up, corticosteroid medication and the WHO-performance were registered at regular intervals. The radiological response was assessed by reviewing all available CT- and MRI-films. Potentially prognostic factors with respect to survival were evaluated by both univariate and multivariate analyses. RESULTS: A clinical response (i.e. clinical improvement) was seen in 24% of the patients. Of the evaluable patients, nearly one-third showed a complete (8%) or partial (22%) radiological response. The median overall survival (OS) and progression-free survival (PFS) after retreatment were 10.9 and 8.6 months, respectively. By multivariate analysis, four independent prognostic factors for survival were identified: (1), the WHO-score before retreatment (P = 0.002); (2), the length of the interval between treatments (P = 0.008); (3), the tumour histology; and (4), the response to initial treatment (P values, 0.04). The median survival times for patients with WHO-scores of 0-1 and > or = 2 were 14.0 and 7.4 months, respectively. Patients with oligodendrogliomas had a median OS of 27.5 months, whereas patients with astrocytomas had a median OS of 6.9 months after retreatment. Long-term complications of retreatment were seen in three patients, all of whom had a cumulative BED(2) of > 204 Gy (with alpha/beta = 2 Gy). The quality of life after retreatment, however, was well preserved in the majority of patients. They remained ambulant and capable of self-care until the time of progression which occurred after 8.6 months (median PFS). CONCLUSIONS: After an initial treatment with radiation up to tolerance levels of normal brain tissue, reirradiation of recurring primary brain tumours seems feasible. During the time until clinical progression, patients remained independent with a reasonable quality of life.

Effect of CT-based treatment planning on portal field size and outcome in radiation treatment of localized prostate cancer.

The portal field sizes of 361 consecutive patients treated with curative radiotherapy for localized prostate cancer were measured. The introduction of CT-based information resulted in a significant increase of field sizes, leading to an almost doubling of the treated volume, some increase in late rectal toxicity, but also in local control.

Is the chest radiograph a reliable tool in the assessment of tumor response after radiotherapy in nonsmall cell lung carcinoma?

BACKGROUND: The purpose of this study was to evaluate whether the chest radiograph is a reliable tool to assess response to radiotherapy. MATERIALS AND METHODS: Pre- and post-treatment chest radiographs and computed tomographs (CT) of 63 patients with nonsmall cell lung cancer (NSCLC) treated by radiotherapy were reviewed by four observers with regard to suitability for tumor measurement, and response. Suitability for tumor measurement was expressed as the number of measurable diameters. In addition, the consequences to clinical outcome were studied by survival analysis. RESULTS: The CT turned out to be more suited for tumor measurement before as well as after radiotherapy, resulting in an increase of the number of measurable cases. The number of measurable cases with CT was 52 (83%) as compared to 28 (44%) with chest radiography. Especially in case of centrally localized tumors, the presence of an atelectasis, or squamous cell carcinoma, CT contributed to a higher rate of measurable cases. The interobserver agreement with regard to response using chest radiograph was good (mean kappa = 0.74). In 25 of 28 cases (89%) measurable with CT as well as with chest radiograph, response was equally classified. When CT was used, the median survival of the responders was 14.2 months as compared to 6.8 months of the nonresponders. When chest radiograph was used, the median survival of these groups was 12.0 and 6.6 months respectively, which was not significantly different when response was assessed by CT. CONCLUSION: We conclude that CT is more suited for tumor measurement because more measurable lesions can be found and more evaluable lesions on chest radiograph become measurable on CT. The chest radiograph does have a valuable role to play in those lesions that are measurable because of the good interobserver agreement with regard to the response classification, the high overall agreement between CT and chest radiograph in case of measurable cases, and the lack of important differences with regard to survival.