An audit of delays before and during radical radiotherapy for cervical cancer - Effect on tumour cure probability

Aim: To evaluate the potential impact of time delay before and during radical radiotherapy for cervical carcinoma at Addenbrooke's Hospital. Materials and methods: An audit was undertaken which recorded the number of gaps during external beam radiotherapy (EBRT), overall treatment time, and delay between first oncology consultation to start of radiotherapy, for patients receiving primary radical radiotherapy for cervical cancer in 1996,. 1998 and 2001. Radiobiological modelling was used to calculate the tumour control probability (TCP). A questionnaire survey of 62 oncology departments in the U.K. was carried out for comparison. Results: The percentage of patients completing EBRT without any interruptions was 22, 67 and 94% in 1996, 1998, and 2001, respectively (P=0.0009). The median overall treatment time was 49, 42 and 39 days in 1996, 1998 and 2001, respectively (P=0.001). However, the median waiting time to start of radiotherapy increased from 14 days in 1996 to 18 days in 1998 and 35 days in 2001 (P=0.007). Conclusion: The results from the national survey showed that this pattern of improved overall treatment times accompanied by deterioration in waiting times was also seen in most other U.K. centres. Radiobiological modelling showed that any potential gain in TCP resulting from shorter overall treatment times could be offset entirely by the adverse effect of increasing waiting times. The calculations suggest that the tumours most likely to be adversely affected by long waiting times are those with shorter volume doubling times or a medium chance of tumour control at the outset of treatment. A system of patient triage, and prioritization of patients deemed most likely to benefit from a reduced waiting time, may be necessary in the current climate of limited radiotherapy resources. (C) 2003 Published by Elsevier Science Ltd on behalf of The Royal College of Radiologists.