Efficacy of different regimens of adjuvant radiochemotherapy for glioblastoma

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Background: Purpose/Objective(s): We retrospectively analyzed the impact of different temozolomide (TEM) regimens in a group of patients treated for glioblastoma compared to patients only receiving postoperative radiotherapy. Methods: Between 01/2000 and 12/2003, 75 consecutive patients underwent radiotherapy. 52 patients received exclusively radiotherapy, 17 patients radio-chemotherapy with low-dose TEM (20 mg/m2) given in 2 daily single doses in combination with an inhibition of cyclooxygenase-2, 6 patients radio-chemotherapy with high-dose TEM (50mg/m2) followed by adjuvant TEM (150–200mg/m2) for 5 days during each 28-day cycle up to 6 cycles. Patients were monitored with MRI every 8 weeks. Aggressive treatment for recurrent disease consisted of re-operation, re-irradiation (fractionated stereotactic radiotherapy 12 x 3 Gy) and/or chemotherapy. Results: The groups treated with high-dose TEM and low dose TEM showed the longest overall survival (OS) (median OS 21 months and 17 months, respectively). Median OS of 9 months for the radiation alone group was condiserably shorter. The same positive trend on prolonged OS was confirmed when either only patients submitted to maximally radical resection or for patients with KPS>70 were considered. No statistically significant difference was observed in terms of progression free survival (PFS). Conclusions: Patients treated with adjuvant TEM either inside or outside study protocols had survival times similar to other reports or randomized studies. The absence of influence of TEM on PFS could either depend on the unavoidable drawbacks and bias of retrospective investigations or on the definition of relapse used. Aggressive and early treatment for recurrent disease results in median survival times approaching 2 years.

No significant financial relationships to disclose.

Intraoperative radiotherapy (IORT) with low-energy x-rays for breast cancer

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Background: IORT for breast cancer using either electrons or low-energy x-rays is of increasing interest over the last few years. In our institution, IORT is delivered by a mobile x-ray source (Intrabeam™) producing isotropic 50 kV x-ray fields. Because this treatment method includes single high doses to the normal breast tissue, careful and long-term evaluation of early and late toxicity is mandatory. To date there are still fewdata on long-term follow-up of patients treated with low-energy x-rays. Methods: Between 2/02 and 12/06 204 breast cancer patients received IORT either as a tumour-bed boost (133) followed by 46 Gy external beam radiotherapy (EBRT) or as partial breast irradiation (PBI) only (71). Median age was 66.4 years (35–95), median tumour size was 9 mm (1–45). Spherical applicators (median 4. 0 cm) were inserted into the tumour-cavity and a single dose of 20 Gy was given. Follow-up (f/u) included physical examination and ultrasound 1 week, 2 months, then every 6 months after therapy and mammography at yearly intervals. Radiobiological modelling of the expected spatial distribution of late reactions was done for typical cases using the linear-quadratic model with special consideration of relative biological effectiveness, spatial dose distribution and dose rate. Results: Median f/u was 28 months (1–56). Minor postoperative side effects included erythema (5%), delayed wound healing (4%), mastitis (1%) and hematoseroma (4%). A fibrotic induration of the tumour bed was observed in 9, 18, 24, 23, 26% and 24% of the patients at 2, 6 12, 24, 36 and 48 month f/u. These fibrosis rates were distributed equally in both groups. Reoperation was required in 2 patients after 10 (fibrosis) and 12 months (fat necrosis). Conclusions: Although two thirds of the patients were treated with a combination of IORT and EBRT, acute reactions in all patients were mild. A fibrotic induration confined to the tumourbed was observed in up to 25% of all patients after 2 years. The low level of clinically observed late reactions so far is in agreement with predictions from radiobiological modelling.

No significant financial relationships to disclose.

Radical Radiotherapy For Bladder Cancer: Retrospective Analysis of a Series of 459 Patients Treated in an Italian Institution

AIMS

To contribute to the available evidence about the efficacy of exclusive radiotherapy for bladder cancer through a retrospective analysis of a large series of patients consecutively treated in a single institution.

MATERIALS AND METHODS

A total of 459 patients with UICC categories T1-T4, N0-Nx and M0 bladder cancer consecutively treated with radiotherapy alone with radical intent formed the clinical basis for this study. Many of them (and particularly the T1 cases) had poor medical conditions or were unfit for surgery. About half of the cases (54%) had a T2 tumour, and about 18% had T3-T4 disease. Eighty per cent of the cases received minimal doses in the target volume in the range 60-70 Gy; pelvic lymph nodes were treated in 34%. Simple radiotherapy techniques were used in most cases. Average follow-up for living patients was 4.4 years. Results were analysed according to number and type of relapses: overall survival, disease-specific survival, failure-free survival probability, acute and late toxicity (RTOG scale).

RESULTS

Actuarial 5-year overall survival, disease-specific survival and failure-free survival rates at 5 years for the entire series were 36%, 56%, 33%, respectively. Age, T category (for all the end points) and tumour dose (only for failure-free survival) were significantly related to prognosis at multivariate survival analysis. Late enteric toxicity (6.1% of the cases) was significantly linked with the treated volumes (univariate analysis). Urinary late toxicity (23% of cases) was linked with age and T category (multivariate analysis). In both cases, toxicity was mostly Grade 1 or 2.

CONCLUSIONS

The results of radiotherapy in this negatively selected series, accrued over a long period of time in patients treated with unsophisticated techniques, are reasonably good; they add to the evidence available to support the use of modern bladder-sparing programmes, including the association of chemo- and radiotherapy.