Escalation and intensification of radiotherapy for stage III non-small cell lung cancer: opportunities for treatment improvement.

In this overview we review and model how radiotherapy tumour control and complication rates vary with dose, fractionation, schedule duration, irradiated volume and use of chemotherapy for stage III non-small cell lung cancer (NSCLC), and use the modelling to study the effectiveness of different NSCLC dose-escalation approaches being developed in the UK. Data have been collated for pneumonitis, lung fibrosis, early and late oesophagitis, cord and cardiac complications, and local progression-free survival at 30 months. Dependences of the various end points on treatment-related factors are catalogued and analysed using the linear-quadratic incomplete repair model to account for dose and fractionation effects, making linear corrections for differences in schedule duration, and loosely characterising volume effects using parallel- and series-type concepts. Tolerance limits are calculated for the different end points and distilled into ranges of prescribed dose likely to be tolerable when delivered in 2.5 and 4 week radiation and 6 week chemoirradiation schedules using conformal techniques. Worthwhile ( approximately 20%) gains in 30 month local progression-free survival should be achievable at safely deliverable levels of dose escalation. The analysis suggests that longer schedules may be more beneficial than shorter ones, but this finding is governed by the relative rates of tumour and oesophageal accelerated proliferation, which are quite imprecisely known. Consequently escalated 2.5, 4 and 6 week schedules are being developed; each should lead to useful improvements in local control but it is not yet known which schedule will be most effective.

Phase II study of carboplatin and adriamycin as second line chemotherapy in small cell lung cancer.

A total of 25 patients with small cell lung cancer (SCLC) were treated with carboplatin and Adriamycin (CA) following symptomatic relapse after initial therapy, or because of static or progressive disease during primary treatment. Nine patients had disease within the thorax, and 16 had extensive metastases at relapse. The overall response rate to CA was 64% (20% complete response: CR; 44% partial response: PR). Survival from presentation in 22 of the patients who have died was 6-36 months (median 13 months), and the median survival from the commencement of CA was 23 weeks (range 1 week-11.5 months). The duration of CR was 4-8 months, and of PR 2-7 months. Hospital admission was required following 12% of cycles for management of the complications of treatment. The increasing use of first line regimens of short duration means that reassessment should be made of the activity of further therapy at relapse.

A short fractionation radiotherapy treatment for poor prognosis patients with high grade glioma.

Thirty-two patients prospectively identified as having poor prognosis high grade glioma, with a MRC prognostic score >25, were treated with a short palliative course of radiotherapy. A total dose of 36 Gy in 12 fractions was given to the tumour, including oedema and a 2 cm margin, using parallel pair fields prescribed to the midplane with MV photons. Twenty-eight patients completed treatment as planned, while four failed to complete treatment because of clinical deterioration or death. The median survival for the whole group was 16 weeks, with seven patients surviving for more than 6 months. Approximately two-thirds of the surviving patients remained at home after the completion of treatment. A matched case-control comparison with data from patients in previous MRC studies who had received a 6-week course of treatment shows that, for this group of patients, survival is similar (hazard ratio 1.0; 95% confidence interval (CI) 0.57-1.74). The 95% CI for the difference in median survival time excludes a reduction of more than 7 weeks with the 36 Gy course. This shortened radiotherapy regimen may therefore be satisfactory for most poor prognosis patients. However, patients with performance status 3 gained little benefit from treatment, and it is suggested that this group should have a trial period of assessment at home prior to a decision on treatment.

Experience of first- and subsequent-line systemic therapy in the treatment of non-small cell lung cancer.

INTRODUCTION: The treatment of advanced non-small cell cancer (NSCLC) has changed with multiple new treatment algorithms proposed based on histological and molecular subtyping but low mutation rates will ensure the dominance of cytotoxic chemotherapy. Accordingly, we undertook a detailed review of our practice delivering multiple lines of systemic therapy. METHOD: We undertook a retrospective review of consecutive patients presenting with advanced (stage IIIb/IV) NSCLC treated with systemic therapy at two UK hospitals during a 2-year period, January 2007 to December 2008. RESULTS: A total of 130 patients were identified, treated with predominantly carboplatin/gemcitabine (20 initially radically). Fifty of 110 patients (45%) treated with first-line systemic therapy subsequently received second-line therapy, of which 10 patients received third-line and two patients fourth-line therapy. Sixty three of 110 first-line patients (58%) achieved clinical benefit, 19 out of 50 (38%) in the second-line, 6 out of 10 (60%) in third-line but both patients progressed at fourth-line. Median overall survival for 110 patients was 10 months (95% confidence interval [CI] 8.6-11.4); but 16 months (95% CI 14-17.9) in those receiving multiple lines. Median survival from the first cycle of last-line treatment to death in the multiple therapy lines was 5 months (95% CI 2.6-7.3) and the majority of patients spent more time off treatment. CONCLUSION: Overall our outcomes are consistent with published data and show good survival times can be achieved. The future of advanced NSCLC is in selecting the best treatment approach on a histological and genotypic basis.

Carbogen breathing with nicotinamide improves the oxygen status of tumours in patients.

Nicotinamide and carbogen breathing are both effective radiosensitisers in experimental tumour models and are even more effective in combination. This study was to investigate the feasibility of using the agents in combination in patients and to measure their effect on tumour oxygenation. Twelve patients with advanced malignant disease were treated with 4-6 g of oral nicotinamide (NCT) in tablet formulation. Ten of these 12 patients breathed carbogen (95% oxygen, 5% carbon dioxide) for up to 20 min at presumed peak plasma NCT concentration (Cpeak) and had tumour oxygen partial pressure (pO2) measured using the Eppendorf pO2) histograph. The mean Cpeak values were 82, 115 and 150 micrograms ml-1 for NCT doses of 4, 5 and 6 g respectively and were dose dependent. The time of Cpeak was independent of dose with an overall mean of 2.4 h (range 0.7-4 h). NCT toxicity occurred in 9 out of 12 patients and was mild in all but one; carbogen was well tolerated in all patients. Following NCT only two patients had significant rises (P < 0.05) in tumour median pO2. During carbogen breathing, eight out of ten patients had early highly significant rises in pO2 (P < 0.0001), of which six continued to rise or remained in plateau until completion of gas breathing. Six patients had hypoxic pretreatment values less than 5 mmHg, which were completely abolished in three and reduced in two during carbogen breathing. In conclusion, the combination of NCT and carbogen breathing was generally well tolerated and gave rise to substantial rises in tumour pO2 which were maintained throughout gas breathing. These results should encourage further study of this potentially useful combination of agents as radiosensitisers in the clinic.