Prognostic impact of time from diagnosis to start of radiotherapy in anal cancer
Jakob Hallström, Anders Johnsson, Martin P. NilssonAbstract
Aim
A prolonged time from diagnosis to start of radiotherapy (TTRT) for malignant disease may negatively influence survival, but studies in squamous cell carcinoma of the anus (SCCA) are largely lacking. The purpose of this study was to investigate the impact of TTRT on overall survival (OS) and anal cancer‐specific survival (ACSS) in a nationwide population‐based cohort from the Swedish Anal Cancer Registry.
Method
Patients with non‐metastatic SCCA treated with curative intent definitive radiotherapy (93.3% concomitant chemotherapy) during 2015–2023 were included ( n = 958). According to national guidelines TTRT should be ≤ 46 days and this was used as a cut‐off in the primary analyses. Cox proportional hazards models were used to estimate hazard ratios for OS and ACSS. Variables with p < 0.10 in univariable analyses were entered into multivariable models, with TTRT included in all models.
Results
The median TTRT was 48 days (range 17–350), and in 55% of the patients it exceeded 46 days. Old age, poor performance status, small tumour size, absence of lymph node metastasis and no concomitant chemotherapy were associated with TTRT >46 days. With a median follow‐up of 43 months, TTRT > 46 days had no impact on OS or ACSS. Sensitivity analyses using alternative TTRT cut‐offs and restricting the analysis to high‐risk subgroups showed similar results.
Conclusion
Moderate delays beyond 46 days from diagnosis to radiotherapy initiation did not adversely affect OS or ACSS in patients with SCCA.