[Effects of the time interval between surgery and radiotherapy on the treatment results]

The timing of surgery and postoperative radiotherapy--especially if combined with chemotherapy--has been a subject of interest over the past years.

This analysis was based on a literature review of mostly retrospective publications. Data concerning the interval between surgery and radiotherapy were correlated with the locoregional control, incidence of distant metastases and prognosis of breast cancer, lung carcinoma, and head and neck carcinomas.

The reviewed data did not show a clear relationship of the time interval between surgery and start of radiotherapy and locoregional control. However, evaluation of the data was difficult, because in most publications, retrospective analyses were performed and other prognostically more relevant parameters may influence locoregional control stronger than the time interval. In patients with head and neck carcinomas, there is a negative effect of time interval between surgery and radiotherapy on local control if unfavorable factors exist, i.e., close surgical margins, unfavorable pathohistological parameters and low radiation dose. In patients with breast cancer who do not receive chemotherapy, there are inconsistent reports in the literature. If additional chemotherapy is necessary, the sequence surgery, chemotherapy and radiotherapy seems adequate. Although some data suggest that delaying the initiation of radiotherapy due to chemotherapy may increase the risk of local recurrences, there may, on the other hand, be an increased likelihood of systemic metastases, if radiotherapy is applied before chemotherapy. Concerning lung cancer, only one retrospective analysis exists suggesting a better survival of patients with an interval of more than 36 days between surgery and radiotherapy as compared to patients with a shorter interval.