A comparison of outcomes for patients with oral squamous cell carcinoma at intermediate risk of recurrence treated by surgery alone or with post-operative radiotherapy

Summary Controversy remains about which patients at intermediate risk of recurrence of oral squamous cell carcinoma would benefit from radiotherapy. A retrospective review of computerised database and medical records for 462 consecutive patients at the Regional Maxillofacial Unit in Liverpool who were treated with primary surgery with or without post-operative radiotherapy was carried out. We classified 29% (134) of patients as being at ‘low’ risk of disease recurrence (pT1-2, N0 with clear margins), 29% (135) at ‘high’ risk (involved margins or lymph node extracapsular spread) and the remaining 42% (193) at ‘intermediate’ risk. Of those at intermediate risk, 41% (80/193) received adjuvant radiotherapy and their 5 year survival (SE) was 54% (6%) compared to 71% (5%) for those with primary surgery alone ( P  = 0.002). A higher proportion of patients having radiotherapy had loco-regional recurrence (19/80 24%) compared to those treated by surgery alone (17/113 15%). The improved salvage rate for recurrent disease in the surgery alone group (8/17 53%), compared to those receiving radiotherapy (2/19 13%, P  = 0.05), indicates an advantage in withholding radiotherapy for patients at intermediate risk of recurrence. This study indicates a potential disadvantage associated with the use of postoperative radiotherapy for patients at intermediate risk of recurrence. A randomised trial comparing a watch and wait policy to postoperative radiotherapy in patients with an intermediate risk of recurrence is required to confirm the trend indicated in this retrospective data.