Effect of gap length and position on results of treatment of cancer of the larynx in Scotland by radiotherapy: a linear quadratic analysis.

PURPOSE: This paper reports on the analysis of the effect of the length and position of unplanned gaps in radiotherapy treatment schedules. MATERIALS AND METHODS: Data from an audit of the treatment of carcinoma of the larynx are used. They represent all newly diagnosed cases of glottic node-negative carcinoma of the larynx between 1986 and 1990, inclusive, in Scotland that were referred to one of the five Scottish Oncology Centres for primary radical radiotherapy treatment. The end-points are local control of cancer of the larynx in 5 years and the length of the disease-free period. The local control rates at > or =5 years, Pc were analyzed by log linear models and Cox proportional hazard models were used to model the disease-free period. RESULTS: Unplanned gaps in treatment are associated with poorer local control rates and an increased hazard of a local recurrence through their effect on extending the treatment time. A gap of 1 day is potentially damaging but the greatest effect is at treatment extensions of 3 or more days, where the hazard of a failure of local control is increased by a factor of 1.75 (95% confidence interval 1.20-2.55) compared to no gap. The time factor for the actual time was imprecisely estimated at 2.7 Gy/day with a standard error of 13.2 Gy/day. Among those cases who had exactly one gap resulting in a treatment extension of 1 day, there is no evidence that gap position influences local control (P = 0.17). The treatment extension as a result of the gap is more important than the position of the gap in the schedule. CONCLUSIONS: Gaps in the treatment schedule have a detrimental effect on the disease-free period. A gap has a slightly greater effect than an increase in the prescribed treatment time. Any gap in treatment is potentially damaging. The position of the gap in the schedule was shown to be not important.

Referral patterns within Scotland to specialist oncology centres for patients with testicular germ cell tumours. The Scottish Radiological Society and the Scottish Standing Committee of the Royal College of Radiologists.

Details of 1123 patients registered in Scotland between 1983 and 1990 for testicular cancer under the Scottish Cancer Registration Scheme were obtained and compared with registrations within the five Scottish oncology centres. Some registration discrepancies were identified. Twenty-eight cancer registrations (2.5%) were coded to the wrong site, 29 patients seen at oncology centres had no cancer registration and 14 cancer registrations had the wrong histology. Five hundred and twenty-seven patients with testicular non-seminomatous germ cell tumours (NSGCT) and 567 with testicular seminoma were identified. Referral rates to specialist oncology centres for testicular germ cell tumours were measured by period and health board area of residence. For the whole study period 92% of NSGCT and 93% of seminoma patients were referred to specialist centres for treatment. Referral rates for different health board areas of residence were not significantly different. This study shows that within Scotland the majority of patients with testicular NSGCT and seminoma are referred to specialist centres, and suggests referral rates of around 92% are underestimates. Access is not related to area of residence.

A Scottish national audit of current patterns of management for patients with testicular non-seminomatous germ-cell tumours. The Scottish Radiological Society and the Scottish Committee of the Royal College of Radiologists.

A detailed casenote review was performed on all 65 patients registered with testicular non-seminomatous germ cell tumours (NSGCT) during 1989 under the Scottish Cancer Registration Scheme. Details of management at presentation and 2 years following diagnosis were recorded and analysed. In a small number of patients an unacceptable delay in diagnosis was noted. Variation was found in the frequency and type of investigations performed on patients placed on surveillance, types of chemotherapy regimens used and numbers of patients entered into trials. Three per cent of patients had a biopsy of the contralateral testis and 27% of patients defaulted from clinic attendance. Considerable variation in the management of testicular NSGCT in Scotland has been identified. The introduction of management guidelines should result in a more consistent approach to the care of these patients. Support, both financial and psychological, may reduce the unacceptable rate of default.

A Scottish national mortality study assessing cause of death, quality of and variation in management of patients with testicular non-seminomatous germ-cell tumours. The Scottish Radiological Society and the Scottish Standing Committee of the Royal College of Radiologists.

A detailed casenote review was performed on 55 patients registered with testicular non-seminomatous germ cell tumours (NSGCT) between 1983 and 1988 under the Scottish Cancer Registration Scheme and who had died by 1992. Details of all aspects of clinical management relating to their NSGCT and death details were extracted and summarised. An assessment was made on whether the patients' management had been optimal. An analysis of 5 year survival rates by the five Scottish oncology centres demonstrated significant differences between centres (range 70.4-94.2; chi 2 = 14.46, d.f. = 4, P = 0.006). Some patients in all centres were assessed as having received suboptimal treatment, but two centres performed less well than the other three. There is a suggestion that the number of patients treated suboptimally decreases with increasing number of patients seen, but this does not reach statistical significance.