The adjuvant management of completely resected SCCHN is somewhat more controversial. In general, postoperative radiotherapy (PORT) is a standard of care for most stage III/IV and selected stage II resected cases. In the last several years, several high-profile randomized trials have shown that the addition of concurrent chemotherapy to PORT improves outcomes for selected patients. The RTOG led a North American Intergroup trial comparing standard PORT with or without three cycles of high dose concurrent cisplatin. The patient population consisted of individuals who underwent complete resection but had positive resection margins at the primary tumor site, multiple pathologically positive lymph nodes in the neck, or one or more lymph nodes in the neck with extracapsular extension. This study showed the chemo radiotherapy had significantly improved local-regional control (LRC) and disease-free survival (DFS) but not overall survival, compared with PORT alone. The EORTC performed a very similar study of PORT +/- chemotherapy, showing that chemo radiotherapy improved overall survival in addition to LRC and DFS (Bernier 2004).
Bernier, et al. (2005) subsequently performed a meta-analysis of the RTOG and EORTC trials. In this exploratory analysis, the primary subgroups of patients who benefited significantly from the addition of chemotherapy were those with positive resection margins and/or nodal extracapsular extension. Other patients did not have a significant benefit from high dose concurrent cisplatin. Specifically in RTOG 95-01, this refers to patients with multiple positive nodes (pN2) without extracapsular spread (ECS). In the EORTC study, this refers to a potpourri of patients, including: pathologic T3-4, N0 cancers (except T3, N0 larynx cancer), perineural and/or vascular invasion irrespective of T-stage, or oral/oropharynx cancer with lymph node involvement at Level IV or V. The failure of cisplatin to significantly improve survival or other clinical outcomes does not, however, mean that these patients have a very good or excellent prognosis. As shown below in Table 1, multiple series of data report a rate of local-regional failure between 15 and 35% for these patients, despite adjuvant RT. Most patients who suffer local-regional failure cannot be salvaged with additional anti-cancer treatment and proceed to die from their cancer. The exact rate of local-regional failure probably depends upon multiple factors, including the number of clinical risk factors present (as described by the University of Florida), treatment related factors (such as the quality of surgery and/or RT, as well as the amount of time required to deliver treatment), and currently poorly understood biological/molecular features of patients' tumors. These complex factors make it very difficult to compare one study to another, particularly retrospective experiences harvested at different institutions over several decades. A relatively large prospective trial would thus provide valuable information to help physicians and patients more precisely identify the risk factors for local-regional recurrence (and other clinical outcomes) after surgery + RT.